LEARNING SOLUTIONS FOR SCOTLAND’S COLLEGES

F0K9 34 Calculations and Practical Techniques in Health Care

August 2007 © COLEG

Calculations and Practical Techniques in Health Care

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Acknowledgements
No extract from any source held under copyright by any individual or organisation has been included in this publication.

© COLEG – Material developed by Cardonald College. This publication is licensed for use by Scotland’s colleges as commissioned materials under the terms and conditions of COLEG’s Intellectual Property Rights document, September 2004. No part of this publication may be reproduced without the prior written consent of COLEG and SQA.

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Contents
Section 1: Introduction to this teaching pack Information about the HNC Health Care Group Award Information about this Unit Why the packs have been written How the pack is organised How to use the pack Scottish Credit and Qualifications Framework (SCQF) and the HNC Health Care Section 2: Session Plans Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15 Week 16 Introduction / Mentor / Holistic care / Models Roper-Logan-Tierney Model / Safe practice in placement Respiration / Peak flow / Oxygen saturations Blood pressure / Pulse / Temperature Height / Weight / Body Mass Index / Fluid balance Specimen collection/ Urine testing Explanation of Skills Booklet Calculations between different units of measurement Calculating decimals, fractions and percentages Administration of medicines Recording of results Interpretation of results - Deviations from normal values Factors affecting reliability of results: Knowledge and understanding of reporting procedures Submission of Skills Booklet Formative Assessment 5 5 5 6 6 7 7 11 13 14 19 20 21 22 22 23 25 27 27 27 27 27 28 28

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Section 3: Handouts for learners Holistic care Models of nursing Communication Worksheet Theory and practice: Respirations, peak flow, oxygen saturation levels Theory and practice: Blood pressure, pulse, temperature Theory and practice: Height, weight, body mass index, fluid balance Theory and practice: Specimen collection, testing urine Calculations between units of measurement Calculations involving decimals, fractions and percentages The administration of medicines Recording of results Interpretation of physiological measurement results Factors affecting reliability of physiological results Reporting procedures Formative assessment Section 4: Assessment guidelines How and where you will be assessed: When you will be assessed If reassessment is required Section 5: References and additional resources

33 35 36 38 40 43 49 63 71 77 83 95 100 101 106 107 108 111 111 111 111 113

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Section 1: Introduction to this teaching pack
This teaching and learning pack Calculations and Practical Techniques in Health Care (Unit No F0K9 34) is one of a series which has been developed to support HNC Health Care. It contains everything you need to deliver this Unit but is also intended as a flexible resource which you can customise by adding your own materials and adapting the information provided to suit your own teaching style and modes of delivery.

Information about the HNC Health Care Group Award
The HNC Health Care Group Award number G8CE 15 is made up of the following Units: DR3N 34 DR3P 34 DR3R 34 DR3T 34 F0K8 34 F0K9 34 F0KA 34 F0KB 33 F0KF 34 Health Care Policy Physiology for Health Care Professionals Positive Health Care for Individuals Psychology and Sociology in Health Care Principles of Health Care Practice Calculations and Practical Techniques in Health Care Health Care Practice Experience Physiology of the Reproductive System Health Care Graded Unit

Note: All Units are mandatory

Information about this Unit
This Unit is intended to develop the candidate’s ability to carry out calculations and practical techniques that are frequently used in health care. There are three learning outcomes: 1. Demonstrate a holistic approach when carrying out practical techniques in health care 2. Carry out calculations and practical techniques in health care 3. Record, interpret and report results of practical techniques.

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Why the packs have been written
The packs have been written by tutors across Scotland who are experts in their own field and who have a tradition of working together and pooling resources for the benefit of learners undertaking study at these levels. By drawing upon their expertise we aim to ensure that you have learning and teaching materials of the highest possible quality and that information is current. Aware of how time consuming it is to prepare and produce teaching and learning materials, our intention is not to replace the important professional and personal role of tutors but to support them.

How the pack is organised
There are five sections in the pack: Section 1 (this one): Introduction to this teaching pack The introduction provides background information about the pack and the specific Unit it relates to. Section 2: Session Plans These give guidance for tutors on delivering the session, an outline of the information and key points which should be covered in the session, suggestions for activities which can be used during the session and self directed activities which candidates should carry out in their own time and report back on at the next session (some of which may count towards assessment). Section 3: Handouts for learners This section contains handouts which should be photocopied and distributed to candidates as part of induction, during the session as an aide memoire or activity sheet, to guide their self directed learning or for any other similar purpose. Section 4: Assessment guidelines This provides guidance to tutors on how to prepare candidates for assessment and also information on assessment requirements. This should be considered alongside the assessment exemplar for this Unit. Section 5: References and additional resources This section contains a list of additional resources (publications and websites) which may be useful to candidates.

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How to use the pack
The pack is designed as a flexible resource and takes into account the fact that different centres have different modes of delivery. It is suitable for both experienced tutors and those who are new to the field of study. You can either follow the sequence presented or select particular sessions as required, substituting your own materials as you wish. All teaching-learning sessions are self contained and can be used singly or combined with others. Any timings suggested are notional and can be adjusted to suit different requirements. We suggest that you spend some time familiarising yourself with the layout and contents of the pack prior to use.

Scottish Credit and Qualifications Framework (SCQF) and the HNC Health Care
The HNC Health Care is at level 7 on the SCQF. The information and activities in the pack are designed to enable candidates to develop the advanced knowledge, skills and understanding commensurate with this level. This includes: Knowledge and understanding Demonstrate and/or work with: • • • • a broad knowledge of the subject/discipline in general knowledge that is embedded in the main theories, concepts and principles an awareness of the evolving/changing nature of knowledge and understanding an understanding of the difference between explanations based in evidence and/or research and other forms of explanation and of the importance of this difference.

Practice: Applied knowledge and understanding Use some of the basic and routine professional skills, techniques, practices and/or materials associated with a subject/discipline. Practise these in both routine and non-routine contexts. Generic cognitive skills Present and evaluate arguments, information and ideas which are routine to the subject/discipline. Use a range of approaches to addressing defined and/or routine problems and issues within familiar contexts.

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Communication, ICT and numeracy skills Use a wide range of routine skills and some advanced skills associated with the subject/discipline - for example: • • • • • convey complex ideas in well-structured and coherent form use a range of forms of communication effectively in both familiar and new contexts use standard applications to process and obtain a variety of information and data use a range of numerical and graphical skills in combination use numerical and graphical data to measure progress and achieve goals/targets.

Autonomy, accountability and working with others Exercise some initiative and independence in carrying out defined activities at a professional level. Take supervision in less familiar areas of work. Take some managerial responsibility for the work of others within a defined and supervised structure. Manage limited resources within defined areas of work. Take the lead in implementing agreed plans in familiar or defined contexts. Take account of own and others’ roles and responsibilities in carrying out and evaluating tasks. Work with others in support of current professional practice under guidance.

A full account of the descriptors for SCQF level 7 is available on www.sqa.org.uk. These should be consulted before embarking on this HN Unit.

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Supporting candidates undertaking this award Candidates undertaking this award are likely to be at care assistant level and should take considerable responsibility for their own learning and development. You should impress upon them from the outset the importance of an active involvement with the learning process. For example, you might remind them of the following points: • • • Learning will only happen if they engage actively with their study. This level of study is advanced and requires considerable commitment and ability. The centre-based and self-directed activities in the pack are designed to help them develop the skills, knowledge and understanding they require to work as a 1st year student nurse (research skills, critical enquiry and analysis). It is important therefore that they undertake all the activities to the best of their ability. Work at this level requires a professional approach, high standards and the understanding of when to refer information to others. The activities they will undertake have been designed to enable them to develop these skills at an advanced level. All of the activities they will undertake will help prepare them for assessment at the required level.

•

•

Support for candidates returning to study Tutors should be aware of the support required by ‘return to learn candidates’ who may not have adequate study, reflection or core skills and might struggle with this award. Your centre may have designed induction programmes specifically for these candidates. Alternatively, you might require them to undertake study of numeracy skills at SCQF level 5 or above prior to undertaking this award or Unit since they will be expected to demonstrate these skills in theory and in practice.

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Section 2: Session Plans
These plans are based on 18 sessions of 2 hours each. Week 1 Introduction to Unit Requirements of qualified mentor/supervisor Explanation of holistic care Introduction to nursing models

Week 2

Roper-Logan-Tierney model of nursing Focal Areas – Activities of Living Safe practice in placement

Week 3

Theory and practice of:

Respirations Peak flow Oxygen saturation levels

Week 4

Theory and practice of:

Blood pressure Pulse Temperature

Week 5

Theory and practice of:

Height and weight/body mass index Fluid balance

Week 6

Theory and practice of:

Specimen collection Testing urine

Week 7

Explanation of Skills Booklet and date for submission of this

Week 8

Conversion between different units of measurement

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Week 9

Calculations involving decimals and fractions

Week 10

Theory and role awareness regarding the administration of medicines

Week 11

Recording of results into case notes (numerically) and charts (graphically)

Week 12

Interpretation of results – deviations from normal values

Week 13

Factors affecting reliability of results:

Environmental Individual factors Faulty equipment Faulty technique

Practical experience in small groups with use of relevant equipment

Week 14

Knowledge and understanding of reporting procedures Practical experience in small groups with use of relevant equipment

Week 15

Submission of Skills Booklet (Outcomes 1 and 2)

Week 16

Formative Assessment – calculations and interpretation of graphs

Week 17

Written Assessment Outcome 3

Week 18

Remediation

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Week 1

Introduction / Mentor / Holistic care / Models

Introduction to Unit This Unit is intended to develop the student’s ability to carry out calculations and practical measurements that are frequently used in health care. There are three outcomes: 1. Demonstrate a holistic approach when carrying out practical techniques in health care. 2. Carry out calculations and practical techniques in health care. 3. Record, interpret and report results of practical techniques. These outcomes will be assessed by the completion of a Skills Booklet which is signed as satisfactory by the workplace mentor and by the assessment of numerical calculations by a written assessment which requires 100% attainment.

Requirements of qualified mentor/supervisor The HNC student will require a first level nurse as their mentor to ensure that all the practical activities required to complete the Skills Booklet are overseen by a competent registered practitioner. Explanation of holistic care – see student handout, Section 3. Introduction to nursing models – see student handout, Section 3.

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Week 2

Roper-Logan-Tierney Model / Safe practice in placement

Roper-Logan-Tierney Model of Nursing – see student handout, Section 3. Focal Areas – Activities of Living – see student handout, Section 3. Suggested responses for student worksheet - see student handout, Section 3. Having a baseline of measurements to work from is imperative. From this subsequent results can be compared which will inform care professionals of the patient’s progress – whether positive or negative. Having thought about the Roper-Logan-Tierney model of care to achieve an accurate history (verbal and non-verbal skills, cultural and privacy considerations) discuss how you could gain an accurate and relevant patient history, using the ALs as prompts, that can be used as a baseline for the purposes of measuring physical and mental health. Some areas of the model will be more relevant than others but all areas should be considered. 1. Ability to maintain a safe environment

Within a hospital setting there are few areas which would pose problems in this respect. Hospital wards are usually warm and clean, however the impact of MRSA and C Diff. requires to be considered, especially in surgical and care of the elderly units. Regular temperature checks would show an increase from the normal baseline if an infection was present. In the community however a more detailed assessment is required – is the house warm, is there dampness, are patients receiving the benefits they are entitled to for heating etc, are there any trip hazards on which someone could fall and lie for several hours? The main problem with unsafe environments in a house is hypothermia, again requiring temperature checks to be undertaken. This is especially so in the elderly or where a patient presents with a chest infection due to poor mobility or dampness which would again increase temperature. Safe environments in the community may also relate to people abusing, for example, drugs and/or alcohol where there may be dirty needles lying about. This would again show infection in the form of a raised temperature if localised infection was present. Cuts from tripping or falling on broken glass may also cause an underlying infection.

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2.

Communicating

This may have little effect on physical measurements being carried out, but may prevent a clear and accurate history being taken. If patients have communication difficulties think of other means of getting the information; for example, previous hospital records, GP records, talking to the family (if appropriate) or use of a translator/signer. Respiratory sounds, for example wheezing, during communication may indicate that there is a history of respiratory disease and the patient can then be prompted with further questions. Evidence of wheezing or difficulty breathing during communication may indicate that respirations, peak flow levels and possibly oxygen saturation levels should be undertaken for this patient. Problems with communication may present in a patient with a urinary tract infection or one who has been poisoned or has overdosed on medication. Urinalysis may be indicated for these patients. Observe non-verbal communication – observation of the patient may communicate to the nurse that the patient is in pain, or their colour may show poor peripheral circulation, jaundice, etc. 3. Breathing

In addition to the problems with breathing which may interfere with communication, the main indicators to be looked at when assessing breathing are the rate, rhythm and depth of respiration. Noisy breathing should also be documented as it may indicate deficiencies in the airways – peak flow and oxygen saturations may therefore be indicated. • • • • • Pain when breathing may indicate rib fractures. Increased rate of breathing may indicate shock associated with bleeding or infection. Abnormal rhythm could be due to pain or perhaps a collapsed lung where paradoxical breathing (inflation of one side of the chest only) may be seen. Shallow breathing may also indicate damage to the lung or infection but may also be an indication of pain following chest or abdominal surgery. Deep breathing may indicate compensatory breathing following damage to the opposite lung or may indicate shock when ‘air hunger’ is noted in severe cases.

The patient should be asked if they smoke as this may affect breathing. Some disease processes which may also affect breathing (for example, asthma, pneumonia, tuberculosis, chronic obstructive pulmonary disease) may be apparent in the patient’s medical history. When assessing respiratory rate the nurse should try not to make it apparent that this is what they are doing because the patient can alter the rate of breathing if they are aware that this is being assessed.

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4.

Eating and drinking

Nutritional and hydration status can have a profound effect on physical measurement. Dehydration can be observed as dry skin with poor elasticity, sunken eyes and dry mouth. Over hydration may be indicated by oedema, especially in the ankles and feet, and may indicate, for example, poor cardiac output and diabetes. Patients who are overweight may also have a higher blood pressure than expected for their age and height, whereas underweight patients may have a lower than normal blood pressure. Eating and drinking are also essential to maintain homeostasis within the body and blood results may indicate deficiencies. Periods of fast, such as Ramadan, should not affect physiological measurements as long as the patient maintains a good nutritional input during non-fasting times of the day. 5. Eliminating

Problems with elimination are, on the whole, due to nutritional problems. The exception is when there is a disease process within the patient, for example carcinoma of bowel (causing constipation and/or obstruction) or carcinoma of bladder (which may be indicated by haematuria, found when carrying out a urinalysis). Urinary infections or renal calculi may also predispose the patient to haematuria. Polyuria may be present in an undiagnosed or poorly controlled diabetic, however this is usually accompanied by excessive intake of fluids – especially sweet drinks. On urinalysis glucose and ketone levels would be high. Polyuria may also occur in a patient who drinks excessive amounts of water and a urinalysis, especially the specific gravity, would indicate a very dilute urine in this case. Or, if a patient appears to be dehydrated, their urine specific gravity may be higher than normal levels due to high urine concentration. Fluid balance charts may be of use where patients are drinking low or high volumes to monitor the amounts of fluid being taken into the body and the amount being eliminated. 6. Personal cleansing and dressing

This Activity of Living is not so relevant as regards physiological measurement unless the nurse, when assessing the patient’s competence in these areas observes, for example, respiratory increase during activity (thus requiring respiratory rate to be carried out), or postural hypotension when, for example, the patient bends over to put on socks or shoes (thus requiring a lying/standing blood pressure review). The condition of the skin for hydration levels, tone, colour, presence of bruising, areas of breakdown and lack of hygiene will have an effect on the provision of care.

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7.

Controlling body temperature

Normally the body temperature is kept within tight limits by the hypothalamus. An elevation in temperature may indicate for example infection or sunstroke. A decrease in body temperature may indicate hypothermia due to exposure from the cold or poor dressing for the environmental conditions. Medically induced hypothermia may be indicated during cardiac surgery to reduce the risk of hypoxia. Under these circumstances a very close control is kept on the patient and their temperature monitored continuously. Time on the operating table may also predispose the patient to lowered body temperature. 8. Mobilising

Postural hypotension may result from the patient mobilising too rapidly and the blood pressure should be checked if this occurs. Pain on mobilisation may be present, especially after abdominal surgery and this would indicate the need for monitoring blood pressure and temperature to rule out underlying internal bleeding or infection. In an immobile patient a risk assessment should be carried out to rule out the presence of pressure ulcers which may develop as a result of ischaemia in the tissues. Any break in the skin makes the patient vulnerable to infection which could be indicated by a raised temperature. Poor mobility in patients may also make them susceptible to deep venous thrombosis and pulmonary embolism. Respirations should therefore be taken in bed-bound patients. 9. Working and playing

In a healthy individual, working and playing would not affect physiological measurement baselines. However, obtaining information about a patient’s employment may indicate areas where there may be concerns. For example, if someone works in a very stressful environment they may have abnormal rises in blood pressure due to stress and anxiety. If someone works, for example, in the sewerage industry they may be exposed to Weils Disease (Leptospirosis) from rat’s urine and this would give rise to increase in temperature due to the presence of infection. Baker’s lung (due to breathing in flour), Psittacosis (pigeon fanciers’ lung) due to breathing in the dust from dried bird faeces and Farmers’ lung (due to breathing in fungal spores from wheat or corn) may also affect the patient, and respiration levels would be above normal expectations. Hairdressers and chemical workers may suffer from eczema due to the exposure of the skin to chemicals. If these areas of eczema become infected a resulting rise in temperature may be recorded.

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10.

Expressing sexuality

This Activity of Living is not so relevant as regards physiological measurement unless the nurse has an awareness of the patient having an infection eg hepatitis or HIV. In these cases staff must be extra vigilant towards infection control when taking specimens of blood etc to ensure there is no danger of needle stick injury. Some infections may contribute to a rise in temperature but in some cases no outward or physiological signs and symptoms may be present. 11. Sleeping

This Activity of Living is not so relevant as regards physiological measurement unless the nurse is taking a set of measurements during the night when the patient is sleeping. It may be that due to the body being in a deep sleep the results are slightly lower than the patient’s normal baseline. 12. Dying

Physiological measurements may not be routinely taken if the patient is in the terminal stages of their illness. However, when taking the patient’s respirations, CheyneStokes breathing may be noted.

Safe Practice in placement Student should be encouraged to look at the ward policy and procedure manual and enclose relevant sections in their Skills Booklet for future reference. The student should always work with their mentor to ensure that safe practice is observed, understood and then practised.

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Week 3

Respiration / Peak flow / Oxygen saturations

Purpose of respiration The respiratory process – chemical and nervous control Composition of inspired and expired air Exchange of gases Patterns of breathing: • Tachypnoea • Bradypnoea • Apnoea • Hypernoea • Hypoventilation • Hyperventilation • Cheyne-Stokes respiration Factors affecting breathing: • Exercise • Smoking • Stress • Drugs • Infection • Head injury • Disease process Respirations - see student handout, section 3 • Respiratory theory and practice Peak flow - see student handout, section 3 • Purpose of peak flow measurement • Factors affecting peak flow measurement • Peak flow practice Oxygen Saturation - see student handout, section 3 • Purpose of oxygen saturation measurements • Factors affecting oxygen saturation levels • Measurement of oxygen saturation levels Practical time should be allowed to undertake the physical measurements (respirations, peak flow and oxygen saturations) in small groups.

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Week 4

Blood pressure / Pulse / Temperature

Blood pressure – see student handout, section 3 • • • • • • The cardiac cycle Definition of blood pressure and normal blood pressure parameters Korotkoff’s sounds Measurement of blood pressure Factors affecting blood pressure Blood pressure anomalies • Hypertension • Hypotension

Pulse – see student handout, section 3 • • • • • Purpose of pulse measurement Pulse sites Pulse – rate, rhythm, volume Factors affecting pulse Pulse anomalies: • Tachycardia • Bradycardia Assessment of pulse

•

Temperature – see student handout, section 3 • • • • • • • Purpose of temperature measurement Temperature regulation and how heat is produced and lost Calculation of centigrade and Fahrenheit Temperature sites and normal parameters Thermometer choice and sites for assessment Factors affecting temperature Temperature anomalies: • Hyperthermia • Hypothermia Assessment of temperature

•

Practical time should be allowed to undertake the physical measurements (blood pressure, pulse and temperature) in small groups.

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Week 5

Height / Weight / Body Mass Index / Fluid balance

Height - see student handout, section 3 Factors affecting human growth: • Heredity / genetics • Hormones • Diet • Infection • Non-organic failure to thrive Measurement and calculation of height

Weight - see student handout, section 3 Factors affecting weight: • Genes • Dietary intake • Physical activity Assessment of weight is carried out for a number of reasons: • to assess weight loss or gain • to determine fluid loss or gain • to calculate drug dosages • to monitor the condition of the female and fetus during pregnancy. Measurement and calculation of weight Body Mass Index: • the BMI score • calculation of BMI Fluid balance - see student handout, section 3 Anomalies of fluid balance: • Oedema • Dehydration Assessment of fluid balance

Practical time should be allowed to undertake the physical measurements (height, weight and BMI) in small groups.

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Week 6

Specimen collection/ Urine testing

Types of specimen that can be collected What specimen to what laboratory? Universal precautions required when taking specimens Procedure for specimen collection - see student handout, section 3 Practical time should be allowed to undertake urine testing in small groups.

Week 7

Explanation of Skills Booklet

Give students their Skills Booklet (For learning Outcomes 1 and 2) from assessment exemplar Explain the requirements of the students and the support and signatures required by their supervisor/mentor Students are to have this booklet completed and submit for marking on Week 15 of this Unit

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Week 8

Calculations between different units of measurement

Fahrenheit to centigrade - see student handout, section 3 Answers to set questions: Convert 95.4ºF to centigrade Convert 106.2ºF to centigrade Convert 82.9ºF to centigrade Convert 98.6ºF to centigrade 35.22ºc 41.22ºc 28.27ºc 37ºc

Centigrade to Fahrenheit - see student handout, section 3 Answers to set questions: Convert 21.7ºc to Fahrenheit Convert 38.5ºc to Fahrenheit Convert 35.9ºc to Fahrenheit Convert 40.3ºc to Fahrenheit 71.06ºF 101.3ºF 96.62ºF 104.54ºF

Feet and inches to metres - see student handout, section 3 Answers to set questions: A patient who is 6 ft 3 inches A patient who is 5ft 8 inches A patient who is 3 ft 4 inches A patient who is 2 ft 9 inches A baby who is 1 ft 6 inches 182.88 + 7.62 = 190.5 = 1.905m = 1.7272m = 1.016m = 0.8382m = 0.4572m

152.40 + 20.32 = 172.72 91.44 + 10.16 = 101.6 60.96 + 22.86 = 83.82 30.48 + 15.24 = 45.72

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Stones and pounds to Kilograms - see student handout, section 3 Answers to set questions: A patient who weighs 11 stone 4 pounds A patient who weighs 17 stone 12 pounds A patient who weighs 9 stone 2 pounds A patient who weighs 5 stone 11 pounds A patient who weighs 25 stone 4 pounds 154 + 4 = 158 ÷ 2.2 = 71.82K

238 + 12 = 250 ÷ 2.2 = 113.64K 126 + 2 = 128 ÷ 2.2 = 70 + 11 = 81 ÷ 2.2 = 58.18K 36.82K

350 + 4 = 354 ÷ 2.2 = 160.91K

Kilograms to pounds and ounces - see student handout, section 3 Answers to set questions: A baby whose birth weight is 3.8Kg: A baby whose birth weight is 4.2Kg: A baby whose birth weight is 2.8Kg: A baby whose birth weight is 5.4Kg: A baby whose birth weight is 1.9Kg: 3.8 x 2.2 4.2 x 2.2 2.8 x 2.2 5.4 x 2.2 1.9 x 2.2 = = = = = 8.36 9.24 6.16 11.88 4.18 = = = = = 8lb 6oz 9lb 4oz 6lb 3oz 11lb 14oz 4lb 3oz

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Week 9

Calculating decimals, fractions and percentages

Explanation of decimal numbers - see student handout, Section 3

• • • •

Multiplying and dividing decimals by 10, 100, 1,000, 10,000 Multiplying decimals Dividing decimals Rounding up and rounding down decimal numbers

Explanation of fractions - see student handout, Section 3

• • • •

Adding and subtracting fractions Multiplying and dividing fractions Changing fractions into decimals Percentages

Answers to set questions: Multiply 34.5 63.43 125.756 1,435.4356 Divide 34.5 63.43 125.756 1,435.4356 X 10 345 634.3 1,257.56 14,354.356 X 100 3,450 6,343 12,575.6 143,543.56 X 1,000 34,500 63,430 125,756 1,435,435.6 X 10,000 345,000 634,300 1257,560 1,4354,356

÷ 10
3.45 6.343 12.5756 143.54356

÷ 100
0.345 0.6343 1.25756 14.354356

÷ 1,000
0.0345 0.06343 0.125756 1.4354356

÷ 10,000
0.00345 0.006343 0.0125756 0.14354356

Answers to set questions: 37.5 x 43.5 25.45 x 35.64 365.456 x 355.432 34.435 x 43.43 Answers to set questions: 32.48 32.48 63.84 63.84
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= = = =

1,631.25 907.0380 129,894.756992 1,495.51205

÷ ÷ ÷ ÷

8 0.8 7 0.7

= = = =

4.06 40.6 9.12 91.2
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Answers to set questions:
2 3 3 + 5 +

3
1

4
2

= = = = = = =

8 9 12 + 12

= = = = = = =

17 12
11 10 19 12

= = = =

1 12 1 110 1 712 1 17 24

5

6 5 10 + 10 9 10 12 + 12
20 21 24 + 24

3
5 3

4 +
6 + 8 -

5
7

6
8

41 24

3 16
1 2 4 3

6 3 16 - 16
10 12 -

3 16 7 12 5 24

5
7

6 8 -

3 12
16 24

21

24 -

Answers to set questions:
1 4 2 4 x 6 x 3 x 2 5 3 8 8 8

= 32 = = = = = = =

2

=

1 16

20 10 5 48 = 24 = 12 6 5 24

=

1

4

5

6 x

1 8

48

1 4
2
5

4 6

÷ 28
÷ 8
÷
3 8

1 4
2 5

4 x 6 x
3 x 6 x

8
8
8 8

2
5
3 1

= = = =

8

8
30

=1 = 1 15 =1 9 =6 3
2 5

5

32 16

1

3
6

9

÷ 18

40 6

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Week 10

Administration of medicines

The role of the NMC in regard to administration of medicine guidelines Explanation of the SI units of measurement Minimising errors Basic guidelines for medication administration Calculations between different units of measurement Calculations relating to the use of a syringe driver

Week 11

Recording of results

Accurate numerical and graphical recording of results Explanation and use of the Early Warning Score

Week 12

Interpretation of results - Deviations from normal values

‘Normal’ guidelines in student handout, section 3

Week 13
Environmental

Factors affecting reliability of results:

Individual factors Faulty equipment Faulty technique

Week 14
NMC Policy

Knowledge and understanding of reporting procedures

Health Board Policy and Procedures

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Week 15

Submission of Skills Booklet

(Learning Outcomes 1 and 2)

Week 16

Formative Assessment

Expected answers: 1 You read a policy document that states that in the event of a major incident each ward must make 10% of their bed occupancy available for receiving the injured. How many beds would you need to make available in a: 10 bedded ward 30 bedded ward 20 bedded ward 2 1 3 2

Following a review of the major incident policy an amendment has been made. Now each ward must make 20% of their bed occupancy available. How many more beds must you make available in each of the wards? 10 bedded ward 30 bedded ward 20 bedded ward 1 3 2

3

A clinical audit on bed occupancy has shown that your ward is under occupied by an average of 15%. You work on a 20 bedded ward. From the clinical audit findings identify the average bed occupancy of this ward. Under occupancy of beds 20 x 15 ÷ 100 = 3 Therefore average bed occupancy = 17

4

You are working in a busy 25 bedded admissions unit. You currently have full occupancy. At the start of the shift 5 discharges are planned and two admissions are planned. However 4 emergency admissions are notified during the course of the morning. Will you have enough beds? 25 – 5 + 2 = 22 + 4 = 26 No. There will be 1 bed short

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5

A patient is prescribed 1 gram of Paracetamol. Each Paracetamol tablet is 500 milligrams. How many tablets would you give? General formula = = dose prescribed dose available 1,000milligram 500milligram = number of tablets to be given = 2 tablets required

6

You have to give an injection of 5 milligrams of Diamorphine. Each vial of Diamorphine contains 10 milligrams in 1mL. How much of the Diamorphine would you draw up from the vial for the injection? Formula for liquid drug doses = = dose prescribed x what it’s in dose available 5 10 x 1mL = 0.5 x 1mL

= 0.5mL to be given 7 A patient is prescribed 20 milligrams Senokot liquid. The label on the bottle states that each 5mLs contains 10 milligrams. How many mLs of the Senokot liquid would you dispense? Formula for liquid drug doses = = dose prescribed x what it’s in dose available 20 10 x 5mL = 2 x 5mL

= 10mL to be given 8 A patient is prescribed an injection of 10 micrograms of Morphine. Each vial contains 10 milligrams in 1mL. What would you do? Check the prescription with the doctor as the amount to be injected is 0.0001mL and this is not a measurable dose. 9 An elderly gentleman who has smoked since he was a teenager now has Ischaemic Heart Disease. You are told his cardiac output is 20% less than someone his age who is healthy. Express this reduction in cardiac output as a fraction.

1
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10

An intravenous infusion of 0.9% Saline 500mLs is to be given over 4 hours. What would the infusion rate be? Standard giving set gives 20 drops per mL 500mL x 20 = 10,000 drops ÷ 4 hours = 2,500 drops per hour 2,500 drops per hour ÷ 60 minutes = 41.66 = 42 drops per minute

11

Express 1,000 micrograms in milligrams. 1 milligram

12

A patient has been prescribed Captopril 12.5 milligrams. The tablets supplied are 25 milligrams and are scored. How would you dispense this medication? Wash hands and put on gloves. Use a tablet cutter to halve the scored tablet. ½ a tablet would be given to the patient and the other ½ discarded.

13

Express 3 grams as milligrams. 3000 milligrams

14

An elderly patient, who is very agitated at night, has been prescribed 50 milligrams of Chlorpromazine at 10pm. The Chlorpromazine supplied is in liquid form, 5 milligrams per mL. How much of the liquid would you dispense? Formula for liquid drug doses = = dose prescribed x what it’s in dose available 50 5 x 1mL = 10 x 1mL

= 10mL to be given

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15

The patient above has also been prescribed a prn (if required) dose of 25 milligrams 4 hourly, with a sub note ‘ no more than 100 milligrams of Chlorpromazine in 24 hours’. Having given the 10pm dose, identify the maximum amount of times you can dispense the prn dose in 24 hours should the patient remain agitated. 50mg dispensed at 10pm leaving 50mg available 25mg can be given if required 50 ÷ 25 = 2 Therefore you can dispense 25mg on 2 occasions if required

16

A young pregnant woman has gained too much weight during her pregnancy. You are told she has gained a further 60% of her body weight. Express this weight gain as a fraction.

3

5

17

One Litre of Hartmann’s solution is being infused at 125mLs per hour. What time span has the infusion been prescribed over? 1,000 ÷ 125 = 8 The infusion has been prescribed to run over 8 hours

18

Round off 0.746 to two decimal places. 0.75

19

Round off 87.713342 to three decimal places. 87.713

20

Multiply: 0.32 x 0.04 0.0128

21

Multiply: 3.2 x 0.4 1.28

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22

Multiply: 0.35 x 10 3.5

23

Divide:

1

4 ÷

1

8

1 8 8 4 x 1 = 4

2

24

Divide:
2 1 3 x 1

1

3 ÷

1

2
2 3

=

= 23

25

Divide: 0.0035 ÷ 100 0.000035

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Section 3: Handouts for learners

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Holistic care
Holistic is defined as being ‘of the whole’. To ensure that the care given to patients is accurate and relevant, the whole person requires to be assessed and the care planned, implemented and evaluated. Holistic care planning requires staff to assess all of the care needs of the patient. Care can be:

• • • •

social physical emotional cognitive

and all of these needs should be assessed with sensitivity towards the patient and with adherence to cultural requirements and within the organisation’s guidelines. Prior to carrying out practical techniques in health care it is essential to carry out a full assessment of the patient. By doing this the nurse will ensure that the practical techniques are relevant to the patient’s current condition and no techniques that should be carried out are missed. The best way to attain a full patient history is by using a model of nursing. This will assist the nurse to focus their thoughts on one area of the patient assessment at a time and will ensure a more reliable and accurate record of needs.

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Models of nursing
There are several models of care used to assess patients. Henderson’s model This model looks at the physiological, spiritual, sociological and psychological needs of the patient and also includes assessment of the environment, patient’s current health and nursing requirements.

Roy’s model This model is an adaptive system broken down into six parts: 1. Assumptions – both scientific and philosophical 2. Persons and relating persons – this looks at the four main needs of humans: physiologic, physical, self concept/group identity, role function/interdependence 3. Environment 4. Health and adaptation 5. Nursing 6. Nursing process. The nursing process part of Roy’s model identifies a problem-solving approach to gathering data. The data is gathered by patient assessment, a nursing diagnosis is then formulated, goals are set for the individual, the nursing intervention is then put in place and its effects are evaluated over a period of time.

Orem’s model This model focuses on the patient’s ability to self care and is used to empower the patient and their family to reach their required goal. The nurse and other allied professionals will be used initially to provide care and teaching to empower the patient to ultimately become independent and deal with their own care and treatment. The nurse is available to the patient in a mainly consultative role.

Roper-Logan-Tierney model This model of nursing is probably the most widely used model. It is broken down into 12 parts making each part more easily assessed. The evidence gained from the assessment will be used to identify and support where nursing intervention is required. The 12 focal areas of the Roper-Logan-Tierney model are described as the Activities of Living (ALs). 1. Ability to maintain a safe environment 2. Communicating
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3. Breathing 4. Eating and drinking 5. Eliminating 6. Personal cleansing and dressing 7. Controlling body temperature 8. Mobilising 9. Working and playing 10. Expressing sexuality 11. Sleeping 12. Dying

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Communication
Communication with patients and their significant others is the main way of collating data for a plan of care. Communication can be verbal and non-verbal and an astute nurse will recognise the many non-verbal cues from patients. When considering communication, the nurse must determine the patient’s ability to communicate. Pain, level of consciousness, cognitive ability, disease processes and language barriers are some of the reasons why an accurate and reliable history may not be forthcoming. Why can pain impair communication? Pain can be overburdening and patients may miss some questions or cues as they may not be fully focussed on the interview taking place. Why can level of consciousness impair communication? If a patient is not fully alert their focus will drift and an accurate and reliable history will not be available to nursing staff. Why can cognitive ability impair communication? If a patient suffers from a degree of dementia their answers may not be current and accurate even although the patient’s responses may sound totally credible. The nurse must ensure that information is checked against another source without breaching the patient’s confidentiality. Why can disease processes impair communication? The most likely disease process to impair communication is aural impairment. If the patient does not hear the question correctly it may be misinterpreted and the patient may provide an incorrect response. If a patient is known to have a hearing impairment the nurse must ensure that the hearing aid, if worn, is in place and working to its optimum level before commencing the patient history interview. Why can language barriers impair communication? The United Kingdom is a multinational and multicultural society with a great number of people living here from different language backgrounds. In response the National Health Service has employed translators/interpreters to ensure that patient history interviews are accurate. Some nurses may use an English-speaking member of the family to translate for them. This is in fact poor practice. The patient may have information to tell you that they do not want their family to know and the questions posed by the interviewing nurse may actually breach their right to confidentiality. A family member may be used and may be useful when extracting basic information from a patient but a translator/interpreter who is bound by NHS confidentiality policy and practice is essential to extract a full, accurate history from the patient.

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Listening is essential to ensure that the facts being given by the patient are accurate and relevant. Listening means ensuring eye contact with the patient and reading back to the person what has been heard and written to ensure that the information is accurate. Sometimes when listening we interpret, incorrectly, what a patient is saying. Reading or reflecting back to them your understanding of what they have said ensures that your interpretation of their words is correct. Privacy can be problem in hospital wards. Bed screens can ensure physical privacy but sounds will carry to other staff and patients in the room. If the patient has a hearing impairment or a piece of information leads the interviewer to believe that continuing with the interview may breach the patient’s right to confidentiality, then the history gathering interview should be stopped until the patient can be provided with a private area where sensitive discussions can take place in complete privacy. By providing the patient with a private area the patient is more likely to provide the interviewer with a complete and accurate history which is essential to ensure that all needs are met. Nursing staff are bound by codes of practice published by the Nursing and Midwifery Council. These codes ensure that nursing staff behave in a professional way towards all patients at all times. For example, confidentiality of patient information is essential and any nurse found to breach this code of practice may have their registration to practice being withdrawn. All registered nurses are therefore accountable for their actions and if a patient feels that their confidentiality is being breached by, for example, not being afforded privacy or a registered translator/interpreter then the nurse will be held accountable. Nurses who work in the multicultural NHS also require to have an understanding of how non-verbal communication, for example stance and gestures, will impact on their patients. An example of this is if the nurse is waiting to take the physical measurements of an Indian person and, while waiting, stands with their hands on their hips. This is a sign of aggression in India and will make the patient anxious and may render the physical measurement invalid due to the patient not being relaxed.

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Worksheet
Having a baseline of measurements to work from is imperative. From this subsequent results can be compared which will inform care professionals of the patient’s progress – whether positive or negative. Having thought about the Roper-Logan-Tierney model of nursing to achieve an accurate history (verbal and non-verbal skills, cultural and privacy considerations) discuss how you could gain an accurate and relevant patient history, using the ALs as prompts, that can be used as a baseline for the purposes of measuring physical and mental health. Some areas of the model will be more relevant than others but all areas should be considered. 1. Ability to maintain a safe environment

2. Communicating

3. Breathing

4. Eating and drinking

5. Eliminating

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6. Personal cleansing and dressing

7. Controlling body temperature

8. Mobilising

9. Working and playing

10. Expressing sexuality

11. Sleeping

12. Dying

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Theory and practice: Respirations, peak flow, oxygen saturation levels
Respirations Respiration is the diffusion of gases between the air in the alveoli of the lungs and the blood in the alveolar capillaries. Respiration is mainly an unconscious action controlled by nervous and chemical factors. The rate may be altered by messages reaching the respiratory centre in the brain via the vagus nerve and also by the chemical composition of the blood – mainly oxygen and carbon dioxide levels. The central control area for breathing is found in the lower part of the brain stem, the medulla oblongata, and is referred to as the respiratory centre. Information from the lungs is carried to the respiratory centre along the vagus nerve. Breathing usually quickens during periods of body activity and slows during periods of sleep. Breathing is controlled by inspiratory and expiratory neurones which maintain an automatic breathing rhythm. During normal breathing, inspiration is an active muscular process. Expiration is passive and relies on the natural elasticity of the tissues to deflate the lungs. The most important muscle for inspiration is the diaphragm, therefore any damage or disease process affecting the diaphragm may cause severe breathing difficulties. The respiratory rate is probably the most important measurement when assessing the clinical condition of a patient. However it is the one which historically is the least recorded. Respiratory rate reflects not only respiratory function but also cardiovascular status such as pulmonary oedema and metabolic acidosis such as that seen in diabetic ketoacidosis. The respiratory rate is assessed to establish a baseline for respirations and to monitor fluctuations in respiration levels. Respirations should be observed for quality, rate and depth. Normal relaxed breathing is effortless, automatic, regular and almost silent. Normal respiratory rate is approximately 12-18 breaths per minute in the adult at rest, 25 breaths per minute for a child aged 5 years and approximately 30 breaths per minute for a baby. The depth of breathing relates to the volume of air moving in and out of the lungs and this volume should be constant with each breath.

Equipment required for carrying out assessment of respirations Watch with a second hand.

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Procedure for assessing respirations 1. Introduce yourself to the patient but do not explain the procedure to them. Attempt to count the respirations when the patient is at rest. This may be done while you are appearing to record the pulse. The reason why you do not explain to the patient that you are going to count their respirations is that an awareness of this procedure being carried out usually results in changes to the respiratory rate as the patient becomes more aware of their breathing. 2. Ensure that the patient is in a comfortable position. This ensures that the patient is comfortable and relaxed and ensures accurate observation of the respiratory process. 3. Observe the movements of the chest wall. This is done to detect any respiratory obstruction. Excessive use of the intercostals and accessory muscles used in respiration can also be monitored and any dyspnoea, difficulty in breathing, can be observed. 4. Evaluate the sounds made while the patient breathes. Normal breathing is almost silent. Any wheezing, or other sounds heard should be recorded on the chart. 5. Count the chest movements for 60 seconds. This allows sufficient time to detect any abnormalities or irregularities. 6. Record the number of respirations per minute. This is essential to monitor any changes or trends in the patient’s respiratory process. Any abnormal fluctuations should be reported to the registered nurse.

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Peak flow The peak flow rate can be described as the maximal expiratory flow rate that can be achieved by the person during a forced exhalation. It is measured using a ‘Wright’s peak flow meter’ which is a small portable device and is easy to operate. Peak flow monitoring is normally indicated in conditions such as asthma where there is a reduction in the diameter of the air passages causing a degree of airflow obstruction. When assessing peak flow measurements the size, age, sex and race of the patient should be considered, as all these factors will have an effect on the baseline result. Examples of normal ranges of peak flow: Man, aged 40, 6 feet in height : 550-720 litres per minute Woman, aged 40, 5 feet 6 inches in height : 355-510 litres per minute If the result of the peak flow measurement is below the baseline norm on more than three occasions asthma could be indicated and the patient should be referred for investigation. Equipment required for carrying out assessment of respirations Wright’s mini peak flow meter.

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Procedure for assessing peak flow 1. Introduce yourself to the patient and explain the procedure you are going to be asking them to carry out. To reduce anxiety levels which have a negative effect on the peak flow measurement. 2. Ensure patient is standing or sitting in an upright position. To maximise lung capacity. 3. Make sure the sliding marker or arrow on the peak flow meter is at the bottom of the numbered scale (zero or the lowest number on the scale). This ensures that the sliding scale marker is always at the same level at the start of each respiratory exhalation. 4. Ask the patient to place the mouthpiece of the peak flow meter into their mouth and close their lips tightly around the mouthpiece. Ask the patient to blow out as hard and as quickly as possible for one breath. Blow a ‘fast hard blast’ rather than ‘slowly blowing’ until air from the lungs is fully expelled. Peak flow is looking at the volume of a forced exhalation and therefore one fast blast of air is required to move the sliding scale measurement on the device. A slow release of all the air within the lungs is more for a measurement of lung volume and this is not the assessment required at this time. 5. Record the peak flow volume as indicated on the sliding scale on the peak flow device. To ensure that you do not forget the measurement. 6. Ask the patient to repeat this procedure three times and record the highest reading on the patient’s chart. Repeating the procedure ensures that the patient is relaxed with the equipment and the process and can carry out the assessment to the best of their ability. Once the patient is used to using this apparatus it will be found that the three attempts are very close in result.

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Oxygen saturation The assessment of patient oxygen saturation levels is now regarded as a standard part of patient assessment. It is carried out through the use of a non-invasive device called a pulse oximeter and gives a good indication of the patient’s cardio-respiratory status by measuring the arterial oxygen saturation of haemoglobin. Oxygen saturation levels are measured with the use of a peripheral probe which is attached to a finger, the ear lobe or the nose and beams of light are passed through the tissues. The light is absorbed by blood and soft tissues depending on the concentration of haemoglobin and a photo detector will convert the saturation values onto a digital monitor. Saturation values are averaged out every 5-20 seconds. This machine also measures the pulse rate. Oxygen saturation levels will be reduced if the patient’s breathing is poor and the airway should be checked to ensure that it is clear and the patient is breathing adequately. Oxygen saturation levels will also be reduced if there is heavy blood loss (which will result in a lack of haemoglobin circulating in the body) or if the patient has a severe chest infection (which will prevent oxygen diffusion into the blood in the lungs). Normal oxygen saturation levels are 96% - 99% Equipment required for carrying out assessment of oxygen saturation level Pulse oximeter

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Procedure for assessing oxygen saturation level 1. Introduce yourself to the patient and explain to them what you are going to do. To reduce patient anxiety levels and get compliance from patient. 2. Plug the pulse oximeter into an electrical socket. To recharge the batteries and ensure accurate reading. 3. Turn on the pulse oximeter and wait for it to go through its calibration and check tests. To ensure accurate and reliable result. 4. Select the probe you require, giving particular attention to correct sizing and where it is going to be positioned. To ensure result is accurate and reliable. 5. Position the probe over the chosen digit, ensuring that it is clean and any nail varnish is removed, avoiding excessive force. To prevent breaking of equipment – these probes are very sensitive and force should never be used. Nail varnish will interfere with the photosensitive light and will give an incorrect result. 6. Allow several seconds for the pulse oximeter to detect the pulse and calculate the oxygen saturation level and then record the displayed result into the patient’s chart. Be cautious when interpreting figures where there has been a sudden drop or rise in oxygen saturation level. If in doubt rely on your clinical judgement and contact a registered practitioner to check your result and the equipment. For example, if an oxygen saturation level suddenly drops from 99% to 82% there is a fault in the machine or the probe. Switch off the machine, reposition the probe and start again – it is physiologically impossible for this drop to be correct. 7. When recording of results is completed unplug the machine and clean the probe gently as per hospital policy. To reduce transfer of infection between patients.

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Theory and practice: Blood pressure, pulse, temperature
Blood pressure Blood pressure is a measurement of the force exerted by blood on the walls of the arteries as the heart pumps blood through the body. The blood pressure is determined by the amount and force of blood pumped and the flexibility and size of the arteries. The blood pressure is highest in the arteries, falls sharply in the arterioles and is lowest in the veins. This is why blood pressure is always measured over an artery. Each completed heart beat is called a cardiac cycle. The cardiac cycle comprises of the systole (period when the heart is contracting) and diastole (period when the heart is relaxing). The blood pressure measures both parts of the cardiac cycle therefore two numbers are registered and recorded – the systole and the diastole. Blood pressure is measured in millimetres of mercury – (mmHg). The systolic reading is always given first, for example 120 over 80 (written as 120/80mmHg). Blood pressure continually changes and may be influenced by activity, posture, emotional state, physical state, temperature, diet and the use of medication. It is normal for the blood pressure to rise slightly during periods of exercise and anxiety and to fall slightly when at rest or sleeping. The main factors affecting the blood pressure are: The volume of blood The greater the volume of blood the greater the pressure in the arteries. The lower the volume of blood the lower the blood pressure. The strength and rate of the heartbeat A strong and rapid heartbeat will increase the volume of blood pumped into the arteries and the blood pressure will show a rise. Elasticity of the artery walls Arteries expand with each surge of blood pumped from the heart. Between the heartbeats when the heart is relaxing they will recoil. This expansion and recoil evens out the flow of blood and maintains the blood pressure. With age the arteries lose some of their elasticity and the blood pressure will rise slightly. The return of blood from the veins Valves in the veins and the squeezing of the skeletal muscle is required to return the blood back to the heart.

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Blood pressure anomalies Hypertension Hypertension is the name given to a high blood pressure – that is any blood pressure measurement consistently over 150/90mmHg. In some patients there is no known cause of hypertension. However there are usually contributing factors and several contributing factors are usually responsible for a consistently high blood pressure. Hypertension is harmful in that it places an undue strain on the heart, it damages the blood vessels and can damage the kidneys if not treated. Controllable causes of hypertension:

• • • • • • • •

excessive body weight high cholesterol levels lack of activity smoking – increased risk of coronary artery disease stress – both emotional stress and physical tension alcohol – regular and heavy drinking salt – can cause an increase in body fluids oral contraceptives – in some patients.

Uncontrollable causes of hypertension:

• • • • • •

heredity – family history of high blood pressure increases risk sex – men have a slightly higher risk; however the risk of hypertension in women increases during pregnancy and after the menopause age – risk of high blood pressure increases after the age of 35. However a healthy lifestyle minimises this risk race – persons from African origins can have a greater incidence of hypertension (for reasons not fully understood) secondary hypertension – caused by other medical conditions ‘white coat’ hypertension – due to the anxiety of having the test performed.

Hypotension Hypotension is the name given to a low blood pressure – that is any blood pressure measurement consistently below 100/60mmHg. It is uncommon for the blood pressure to be too low in a healthy adult; it is usually only seen as a complication of other conditions. For example, haemorrhage, shock, anaemia, anorexia nervosa. Hypotension can be indicated by dizziness/light-headedness, resulting in frequent falls and a lack of energy.

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Equipment required for carrying out assessment of blood pressure Sphygmomanometer and stethoscope Blood pressure recording is normally recorded indirectly using a sphygmomanometer. This is light and easy to carry around. Due to its internal mechanism a sphygmomanometer requires frequent calibration. The recorded BP may be influenced by factors such as equipment. These include accuracy and efficiency of the equipment being used, and the correct technique being employed. A stethoscope is used for auscultation and can be dismantled for cleaning purposes. An Aneroid Sphygmomanometer

A Stethoscope Bell (upper chest piece)

Diaphragm (underneath of chest piece)

Valve Ear pieces

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Procedure for assessing blood pressure 1. Introduce yourself to the patient and give an explanation of what you are going to do. To gain consent and relieve anxiety. 2. Choose the correct cuff for the age and size of patient – the World Health Organisation recommends a 14cm cuff for use in adults. To ensure accurate blood pressure assessment. 3. Assist patient to a comfortable position with arm slightly flexed, forearm supported at heart level and palm turned up. Arm above heart level produces false low reading. Position facilitates cuff application. 4. Expose upper arm fully and palpate brachial artery. Cuff requires to be positioned 2.5cm above the site of the brachial artery and directly onto the skin. Ruffled clothing under cuff will produce incorrect reading. 5. Centre the arrows marked on the cuff over the brachial artery. The cuff should inflate directly over the brachia artery to ensure that the proper pressure is applied during inflation. 6. Ensure the cuff is fully deflated and then wrap it evenly and snugly around the upper arm. Ensures that proper pressure is applied over the artery. 7. If unaware of the patient’s normal systolic pressure, palpate the radial artery and inflate cuff to a pressure 30mmHg above which the pulse disappears. Slowly deflate cuff. Identifies approximate systolic pressure and ensures that you do not inflate the cuff too much causing discomfort to your patient. 8. Place stethoscope earpieces in the ears and be sure that the sounds are clear and not muffled. The earpieces should follow the angle of the examiner’s ear canal to facilitate hearing. 9. Relocate the brachial artery and place the diaphragm of the stethoscope over it. Ensures optimum sound reception.

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10. Close the valve on the pressure bulb of the sphygmomanometer until tight. To ensure no leakage of air during cuff inflation. 11. Inflate the cuff to a pressure 30mmHg above the patient’s normal systolic reading. To ensure accurate pressure measurement. 12. Slowly release valve, allowing drop in pressure of 2mmHg per second. Too rapid or too slow a decline in pressure may lead to inaccurate pressure readings and discomfort and anxiety for the patient. 13. Note the point on the sphygmomanometer when the first clear sound is heard. This is the first Korotkoff sound indicating the level of the systolic pressure. 14. Continue to deflate the cuff gradually, noting the point when the sound becomes muffled. This is the fourth Korotkoff sound and indicates the diastolic pressure. 15. Deflate the cuff rapidly and remove it from the patient’s arm unless there is a need to repeat the measurement. Continued pressure causes arterial occlusion which results in numbness and tingling of the patient’s arm. 16. If the procedure needs to be repeated wait at least 30 seconds before carrying out the procedure again. Prevents venous congestion and a false high reading. 17. Fold up the cuff and store and assist client to regain comfortable position. Ensures client comfort. 18. Record result comparing it with the previous reading or patient baseline. To note any changes which require to be reported to registered nurse.

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Korotkoff sounds Korotkoff sounds are the sounds heard through the stethoscope when carrying out a blood pressure measurement. There are 5 sounds in total: 1. Initial ‘tapping’ sound – you will record this as the systolic pressure 2. Sounds increase in intensity 3. Sounds at maximum intensity 4. Sounds become muffled – you will record this as the diastolic pressure 5. Sounds disappear.

Normal blood pressure levels per age group: Newborn 4 years 6 years 10 years 12 years 16 years Adult 50/27 85/60 95/62 100/65 108/67 118/75 120/80

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Pulse When the left ventricle of the heart contracts oxygenated blood is forced into the aorta causing the arterial walls to dilate and creating a pulse wave. This pulse wave is transmitted through the artery walls. Most arteries run deep in the tissues to prevent them being damaged. However, where arteries are present near the surface of the body, for example, where they cross over a bone, a pulse can be felt if light compression to the area is applied. The term pulse is often referred to, incorrectly, as the number of heart beats per minute. In most persons the pulse is an accurate measure of heart rate; however there can be circumstances when the beat of the heart is not effective enough to cause a pulse wave and in these circumstances the heart rate is much higher than the detected pulse. If the pulse is irregular the apical pulse rate should be taken in conjunction with the radial pulse – two staff members are required for this procedure as the apical and radial pulse must be taken for the same minute of time and then compared. The most common sites for pulse measurement are: Radial artery Brachial artery Carotid artery Femoral artery Popliteal artery Posterior tibial Dorsalis pedis Apical pulse the inner surface of the thumb side of the wrist on medial surface of the elbow cavity on side of neck – best place for finding a pulse quickly if patient’s condition deteriorates the groin behind the knees on the inner aspect of the ankle on the top of the foot auscultation of the heart

Pulses can also be felt on the face in the region of the temples. Normal resting pulse rate per age group: Newborn Infant 2 - 10 years Adolescent Adult 140 - 180 80 - 150 70 - 110 55 - 90 60 - 80

A normal pulse for a healthy adult is 60-80 beats per minute. During sleep the pulse rate will drop. Alternatively the rate will increase during strenuous exercise.
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When obtaining a pulse rate the following must be observed: Rate once the pulse is felt, count the rate for 15 seconds and multiply the total by four if the rate is regular. If the pulse rate is irregular count for one full minute. Compare the assessed rate with the patient’s baseline rate. regardless of the pulse rate the rhythm is normally regular. If there is an irregular rhythm (dysrhythmia) assess how often this abnormal rhythm occurs. When an irregular rhythm is detected an apical pulse in conjunction with a radial pulse should be carried out to detect any pulse deficit. pulse strength should remain consistent with each beat. The normal pulse is full, easily palpated and not easily obliterated by the nurse’s fingers. A bounding pulse is easy to palpate and difficult to obliterate. A weak pulse is thready in character, often more rapid than normal, difficult to palpate and easy to lose.

Rhythm

Volume

Factors affecting pulse rate: Position Age Gender Exercise Temperature the rate rises with changes in position – from lying to sitting to standing. pulse rates are higher in children due to their having a lesser volume of blood circulating in the body. the pulse rate of a female is slightly higher than that of a male. strenuous exercise will increase the heart rate. However very fit people will have a lower resting heart rate (below 60 in fit athletes). an increased temperature will cause a rise in the pulse rate as the body responds to a demand for more oxygen whereas hypothermia will lower the pulse rate. problems with the heart’s conduction system can cause an irregular pulse rate. blood loss will increase the pulse rate initially. If bleeding is not stopped the pulse will gradually slow and the peripheral pulse points – radial, brachial for example will be difficult to palpate. for example digitalis will slow the pulse rate, which is why digoxin should never be administered to a patient who has a pulse rate of less than 60 beats per minute. Atropine will increase the pulse rate.

Disease Haemorrhage

Medications

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Pulse anomalies Tachycardia Tachycardia is the term given to a consistently high pulse – over 100 beats per minute. Causes of tachycardia:

• • • • • •

following strenuous exercise anxiety infection shock haemorrhage cardiac failure.

Bradycardia Bradycardia is the term given to a consistently slow pulse – less than 60 beats per minute. Causes of bradycardia:

• • •

raised intercranial pressure decreased metabolic rate (hypothyroidism) heart block (infarction or ischaemia, vascular disease, idiopathic degeneration, drug induced or related).

Equipment required for carrying out assessment of pulse Watch with a second hand.

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Procedure for assessing pulse 1. Introduce yourself to the patient and give an explanation of what you are going to do. To gain consent and relieve anxiety. 2. Wash your hands. To prevent spread of infection. 3. Select the appropriate pulse site for your patient. Radial artery advantages disadvantages Carotid pulse advantages disadvantages Apical pulse advantages

• • • •

most accessible site easily palpated dressings, casts may block the site less accurate for babies and infants

• easily accessible • best for finding pulse quickly if patient’s condition has deteriorated • none • most accurate for assessing heart function in cases of heart disease • used to confirm any abnormalities detected in radial pulse disadvantages • requires auscultation of the heart

disadvantages

4. Locate a pulse using the index and middle fingers. Never use the thumb due to the fact that there is a palpable pulse in your thumb which you may count instead of the patient’s rate. 5. Count the pulse waves for 60 seconds. To ensure an accurate and reliable result. 6. Assist client to regain comfortable position. Ensures client comfort. 7. Record result comparing it with the previous reading or patient baseline. To note any changes which require to be reported to registered nurse. 8. Wash your hands. To prevent spread of infection.

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Temperature The body normally maintains a balance between heat production and heat loss through the temperature control mechanisms found in the hypothalamus in the brain. Thermal receptors throughout the body stimulate the hypothalamus to either produce heat or conserve heat therefore maintaining homeostasis. Heat is produced in the body in four ways:

• • • •

Metabolism, or the amount of energy used by the body at any time Muscular activity; this includes shivering which raises the metabolic rate and therefore heat is produced Thyroid hormone secretion increases the metabolism Stimulation of the sympathetic nervous system.

Heat is lost from the body in four ways:

• • • •

By radiation of infrared rays from the body, especially when the blood vessels are dilated and therefore nearer the surface of the skin By conduction when cool water or objects are in contact with the skin When heated air on the skin’s surface passes to cooler air by convection By the evaporative effect of sweating.

Body temperature is not completely constant throughout the day, however the average normal temperature for a healthy adult is 36.5ºc-37.2ºc. Temperature is measured in degrees: Degrees centigrade ºc Degrees Fahrenheit ºF

•

To convert Fahrenheit to centigrade: Subtract 32 from the Fahrenheit reading and multiply the remainder by 5/9 C = (F – 32) x 5/9

•

To convert centigrade to Fahrenheit: Multiply the centigrade reading by 9/5 and add 32 to the product F = (9/5 x C) + 32

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Sites for assessing temperature When assessing the site for temperature recording the nurse must first decide whether the core temperature or the skin temperature is to be assessed. The core temperature is the inner body temperature and is usually slightly higher than the skin temperature. Mouth this area is most sensitive to changes in temperature and care must be taken to ensure that the patient has not had a very hot or very cold drink prior to the temperature being recorded or an accurate temperature will not be recorded. the underarm area provides a measurement of the skin temperature. this site measures the internal temperature of the body. It is a useful site to use when the temperature is highly variable or abnormally low. this site is used most regularly for babies and young children using temperature sensitive patches. this is now the most common site for temperature assessment. It measures core temperature and a tympanic thermometer is the normal piece of equipment used. These electronic thermometers will provide an instant temperature reading.

Axilla Rectum Forehead Ear

Average normal temperatures for healthy adults: Site Mouth Axilla Rectum Forehead Ear Degrees centigrade 37.0 36.5 37.5 37.5 34.4 Degrees Fahrenheit 98.6 97.6 99.5 99.5 94.0

There is a variety of clinical thermometers available to measure body temperature and the correct thermometer must be used depending on the site of assessment. Thermometer Disposable Glass (contains mercury) Electronic Tympanic
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Site to be used for assessment of temperature mouth, abdomen, forehead mouth, axilla, rectum, groin The thermometer should remain in place for 3-4 minutes to ensure accurate reading mouth, axilla, rectum ear

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Factors affecting body temperature Age Gender Time of day Stress Environment the very young and the old are more sensitive to changes in temperature. women have more temperature fluctuations than men due to hormonal changes during the menstrual cycle. the body temperature is normally at its lowest between 1 and 4am, and at its peak between 4 and 7pm. physical and emotional stress increase the metabolic rate and therefore will increase the temperature slightly. temperature extremes can raise or lower the body temperature depending on length of exposure.

Temperature anomalies Hyperthermia Hyperthermia or pyrexia describes a body temperature raised above the normal range, consistently above 38ºc. This may occur if the metabolic rate is increased or if the hypothalamus is affected by bacteria, viruses or broken down tissue cells. The aim is to reduce the patient’s temperature to normal levels and this can be done by removing external clothing (whilst maintaining privacy and dignity), the use of a fan or by tepid sponging the patient and allowing evaporation of the water to cool the body. Hypothermia Hypothermia describes a body temperature below the normal range (consistently below 36ºc). This may accompany shock or be brought about by prolonged exposure to cold, wet or windy conditions. Hypothermia may also accompany an excessively low metabolic rate. The aim is to increase the patient’s temperature and this should always be done slowly. Warm drinks, layers of clothing or, in the normally healthy adult, a warm bath to which hotter water is gradually added may assist the temperature to rise. A special low reading thermometer may be required to record the temperature of a patient with hypothermia and a core temperature should be recorded rather than a skin temperature. Equipment required for carrying out assessment of temperature Clinical thermometer.

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Procedure for assessing temperature 1. Introduce yourself to the patient. To gain consent and reduce anxiety. 2. Choose type of thermometer for body site to be used. To ensure accurate measurement. 3. Wash and place glove on dominant hand. To prevent spread of infection. 4. Close bed screens. To maintain the privacy and dignity of the patient. 5. Rinse, clean and shake down, if mercury thermometer is being used. To ensure accurate starting point for recording. 6. For electronic thermometer place disposable cover over thermometer. To prevent spread of infection. 7. Place thermometer in body site and leave for appropriate time. Oral measurement Rectal measurement Axilla measurement Tympanic measurement 2 minutes 2 minutes 5-10 minutes electronic thermometer displays quickly

This ensures accurate reading. 8. Read temperature and record it on the patient’s chart, clean thermometer. Ensures that correct reading is not forgotten and thermometer is ready for the next use on that patient. 9. Restore patient to comfortable position and wash your hands. To aid rest and prevent spread of infection. 10. Report any abnormalities in your findings to a registered practitioner. To ensure early appropriate treatment if required.

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Theory and practice: Height, weight, body mass index, fluid balance
Height The height of the patient is normally calculated (especially in a younger person) to ensure that developmental stages are being met. In post-menopausal women height may be lost due to the reduction of bone mass and therefore height is again an appropriate measurement to be taken. Factors affecting human growth:

• • • •

Heredity / genetics Hormones –secretions from the pancreas, thyroid and pituitary glands are the ones which particularly affect growth Diet – a well balanced diet promotes good growth and repair Infection – can disrupt growth.

Measurement of height Height is measured in metres and centimetres although some areas in the world will continue to use the imperial measurement of feet and inches. Despite conversion charts being available in all areas, we should be able to manually convert. 1 inch = 2.54cms 12 inches (1 foot) = 30.48cms

Therefore a patient who is 5ft 4 inches: 5 foot = 4 inch = 5 x 4 x 30.48 2.54 = 152.40 = 10.16 162.56cm

divided by 100 = 1.6256m

Equipment required for carrying out assessment of height Measurement chart with bar

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Procedure for assessing height 1. Remove patient’s footwear. To ensure feet are flat on the floor to get accurate height measurement. 2. Ensure patient is standing straight with feet together. To gain the most accurate measurement. 3. Lower the measuring bar until it is lightly touching the patient’s head. To gain accurate measurement of height. 4. Record the patient’s height on their chart. To gain a baseline for future reference. 5. Report findings to registered practitioner if appropriate.

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Weight A healthy weight has a positive effect on our wellbeing and health. Being overweight or underweight can contribute to medical problems. There is not one ideal body weight. A healthy weight will be determined by a number of factors. Factors affecting weight:

• • •

genes dietary intake physical activity.

Assessment of weight is carried out for a number of reasons:

• • • •

to assess weight loss or gain to determine fluid loss or gain to calculate drug dosages to monitor the condition of the female and fetus during pregnancy.

Measurement of weight Weight is measured in Kilograms and grams although some areas in the world will continue to use the imperial measurement of pounds and ounces. Despite conversion charts being available in all areas, we should be able to manually convert. Note: 1 Kilogram = 2.2lbs (2lb 3½ ounces) (5 Kilograms = 11lbs) 1 stone = 14 pounds 1lb equals = 16 ounces Therefore a patient who is 79kg: 75Kg = 4 Kg = 15 x 11lb 4 x 2lb 3½ ounces = 165lbs = 8lbs 14 ounces = 173lbs 14 ounces

173 lbs = 12 stone 5 lbs (to convert lbs to stones, divide by 14). 79 Kg = 12 stone 5 lbs and 14 ounces

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A patient who weighs 10 stone 5lb would therefore be in Kg: 10 stone 5lb x 14 = 140lb 5lb 145lb

145lbs divided by 2.2 (to convert lbs to Kg) 10 stone 5lbs = 65.91Kg

Equipment required for carrying out assessment of weight Set of calibrated weighing scales Procedure for assessing weight 1. Note clothing worn by patient. It is useful to wear the same type of clothing at each weighing so that there is not a large discrepancy caused by the weight of the clothing. 2. Allow patient to empty their bladder. Gives more accurate body weight. 3. Check that scale is calibrated to zero. To ensure reliable and accurate measurement of weight. 4. Assist client onto scales then ensure that they are free-standing and not supported. To gain accurate recording. Stretcher or sitting scales are available to patients who are unable to weight bear. 5. Note and record weight. To ensure accuracy of recording and gives baseline for future reference. 6. Assist client off scales. To prevent slips or falls. 7. Clean scales as appropriate. To prevent spread of infection. 8. Report findings to registered practitioner if appropriate.

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Body Mass Index The body mass index (BMI) is a reliable indicator of body fat which is related to the risk of disease and death. The BMI can be determined if the weight and the height of the patient is known. The BMI score means the following: Underweight Normal Overweight Obese BMI below 18.5 BMI 18.5 - 24.9 BMI 25.0 - 29.9 BMI above 30.0

Calculation charts are available, but to manually calculate the BMI of the patient: 1. Ascertain the weight in Kilograms 2. Ascertain the height in metres and multiply that number by itself (height squared [height2]) 3. Divide the weight by the height2 Therefore, to calculate BMI for a patient who has a height of 1.62 metres and a weight of 79Kg: 1. Weight 2. Height 3. Divide BMI = 30.1
2

79kg 1.62 x 1.62 = 2.6244 79 by 2.6244

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Fluid balance The body is made up of approximately 70% water which is taken into the body in the form of fluids and solid food which also contains a percentage of water. The amount of water required daily by the body to maintain health is approximately 2500mL. Water leaves the body in four ways. 1. Through the lungs in expired air 2. Through the skin as sweat 3. Through the kidneys as urine 4. Through the bowel in faeces The amount of water leaving the body through the skin and kidneys will vary – the larger the loss through the skin through sweat (for example in hot climates or hot working conditions) the smaller the amount produced by the kidneys. However to ensure that the kidneys produce an adequate amount of urine to rid the body of waste products in hotter conditions more fluids should be taken into the body on a daily basis. The best indication that the patient is receiving adequate fluid intake is that their urine output over 24 hours is 1,000ml minimum and their tongue and mouth are moist. Fluid balance anomalies Oedema Oedema is the term given to retention of water in the body. It can be recognised by areas of swelling which ‘pit’ when pressure is applied. Pitting occurs due to temporary displacement of the fluid from the immediate area on which pressure is placed. Oedema can put excessive pressure on the heart and kidneys and therefore requires attention to treat the underlying condition causing the oedema to occur. Excessive levels of salt in the body can also give rise to oedema. Dehydration Dehydration is the term given to a deficiency of body fluid. It can be due to an insufficient intake of water or by excessive water loss from the body. Excessive water loss may be due to sweating, severe diarrhoea and vomiting, diabetes mellitus, severe haemorrhage or burns.

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Procedure for assessing fluid balance 1. Inform the patient that their fluid intake and output is being monitored. This ensures their cooperation and assistance. 2. Provide a fluid balance chart and ensure all staff are aware of the need to record all fluid and solids entering the body and all waste leaving the body. To ensure an accurate, reliable record of fluid balance is maintained. 3. Every time the patient has something to eat or drink, or has a new prescribed bag of intravenous fluids set up, this should be recorded accurately in the intake column on the chart. Writing down intake as it occurs ensures that no entries are missed. 4. Every time the patient passes urine or faeces, vomits, bleeds or has a drain emptied the amount of fluid loss should be recorded accurately in the output column on the fluid chart. (Any fluid left in an intravenous infusion bag at the cessation of intravenous therapy should also be recorded as output.) Writing down output as it occurs ensures that accuracy is maintained. 5. At the end of each 24 hour timeframe all intake and output should be added up and the findings recorded and reported to the registered practitioner. To ensure that any changes in treatment are applied as soon as possible.

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Theory and practice: Specimen collection, testing urine
Specimen collection Specimen collection is the collection of a required amount of fluid or tissue for laboratory examination. It is required when laboratory investigation is indicated. Successful laboratory diagnosis depends of the collection of specimens at the appropriate time, using the correct technique and transporting them safely to the correct laboratory without delay. Care must be taken to ensure that specimens are not contaminated and for this reason, and to protect the specimen collector from catching an infection, disposable gloves should be worn and the hands washed thoroughly after the specimen is collected. Specimens should be labelled and bagged immediately after collection and should be transported immediately to the laboratory concerned. If there is going to be a delay in transportation the specimen should be refrigerated to ensure that it is received at the relevant laboratory in the best possible condition. Information which should be provided with each specimen:

• • • • • •

Patient’s name, hospital number, consultant’s name and ward Type of specimen Date and time specimen collected Potential diagnosis Relevant signs and symptoms Any current antimicrobial treatment – e.g. antibiotics, antivirals.

This information ensures that the specimen can be analysed correctly and the report returning from the laboratory is accurate.

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Procedure for obtaining a specimen 1. Inform the patient that a specimen is going to be collected from them and why this is being done. This ensures their cooperation and assistance. 2. Ensure that the bed screens are closed. Ensures that the privacy and dignity of the patient is maintained. 3. Collect all the relevant containers for the specimens and put patient labels on each. To ensure you do not have to leave the patient until all relevant specimens are collected and the bottles do not have to be handled again to put labels in place. 4. Wash hands and put on disposable gloves. To reduce the risk of infection transfer. 5. Position the patient in the position required to ensure accurate swabbing of the affected area if this is the specimen required. To reduce contamination and to expose the patient for as short a time as possible. 6. Reposition the patient in a comfortable position and open the bedscreens. To ensure comfort. 7. Place collected specimens in plastic bags and place laboratory request form in pocket provided in bag. To ensure that the specimen and the request form are taken together to the relevant laboratory. 8. Wash and dry hands thoroughly. To prevent spread of infection. 9. Contact personnel to transfer specimen to the relevant laboratory. To ensure specimen arrives quickly and in good condition. 10. Record in patient notes that the specimen has been collected. To ensure that relevant staff are aware that this procedure has been carried out as requested.

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Testing urine The kidneys remove waste materials, minerals, fluids and other substances from the blood and eliminate it from the body in the form of urine. The kidneys control the level of water in the body through production of urine and this maintains the appropriate concentrations of body minerals and salts. Normal healthy urine is straw coloured, clear and a fresh sample has no odour. Why is urine testing carried out:

• • • •

as part of a routine physical examination (assessment of overall health) to screen for a disease / infection of the urinary tract as an aid to diagnosis of some medical conditions, e.g. diabetes mellitus to monitor treatment of, for example, diabetes mellitus, liver disease, etc.

Factors affecting the content of urine:

• • • • •

diet fluid intake exercise kidney function infection.

Routine urine testing primarily involves observation of the urine for: Colour

• •

Normal urine is clear, pale to deep yellow in colour. Pink/red coloured urine can be a sign of bleeding into the urinary tract or may be due to the fact that the patient eats a lot of beetroot or rhubarb in their diet. Dark coloured urine indicates a more concentrated specimen. Cloudy urine may indicate an infection. Fresh healthy urine smells slightly aromatic. A malodourous specimen is normally an indication of infection. A specimen of urine with a fruity smell may indicate diabetes mellitus.

•
Clarity Odour

• • • •

The composition of urine can change dramatically as a result of disease processes.

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The presence of abnormalities in the urine is an important warning sign of illness and may be helpful in clinical assessment in the following ways:

• • •

To determine the patient’s urine status on admission to the ward as a baseline for comparisons with future urine assessments To monitor changes in the constituents of the urine as a response to medication To be used as a screening test to gather information about the physical status of the patient.

Routine urinalysis is normally a nursing responsibility. It is relatively fast, simple and accurate because of the availability of the dipstick (reagent strip) tests. These dipsticks allow the nurse to test the urine for:

• • • • • • •

Specific gravity pH Protein Glucose Ketones Blood Bilirubin / Urobilirubin

Where abnormalities are present the doctor or nurse in charge may request that a midstream specimen of urine is collected from the patient and sent to the laboratory for more thorough analysis. Examples of changes to the composition of urine and their possible cause. Substance present Glucose Protein Ketones Condition Glycosuria Proteinuria Ketonuria Possible causes Diabetes Mellitus May be seen in pregnancy; when eating a high protein diet; heart failure; severe hypertension; infection; asymptomatic renal disease Starvation; untreated diabetes Mellitus Transfusion reaction; haemolytic anaemia; severe burns Liver disease; obstruction of the bile ducts Kidney stones; infection; trauma

Haemoglobin Haemoglobinaemia Bile Pigments Erythrocytes
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Procedure for testing urine 1. Inform the patient that a specimen is going to be collected from them and why this is being done. To obtain patient consent and cooperation. 2. Ask patient to void next urine specimen into a clean bedpan and let you know that it is now available for testing. Ensures that testing is carried out on a fresh urine specimen. 3. Apply gloves. To prevent contamination of hands from specimen. 4. Remove reagent strips from area of storage and take one out of the bottle. Reagent strips must be stored in line with the manufacturer’s instructions and this may mean that they are stored in a dark cupboard or in a refrigerator. Removing one and sealing the bottle again ensures that their integrity is preserved for future use. 5. Completely immerse the reagent strip into the urine, remove immediately and tap against the side of the bedpan. Ensures that urine covers all areas of the strip but excess is removed so that contamination does not occur between test areas. 6. Wait the required time and read the strip against the colour chart provided on the side of the bottle. Ensures an accurate and reliable result. 7. Dispose of sample and used reagent strip and wash hands thoroughly. To prevent spread of infection. 8. Record results of testing in patient chart and report any abnormalities to the registered practitioner.

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Procedure for recovering mid-stream specimen of urine (for laboratory analysis) 1. Inform the patient that a specimen is going to be collected from them and why this is being done. To obtain patient consent and cooperation. 2. Ask patient to clean labia or glans area with soap and water (NOT antiseptic). To ensure specimen is uncontaminated. 3. Patient should pass first part of urine stream into toilet, catch the next part of the stream in a sterile container and complete their urine void into the toilet. This ensures that the sample collected is as sterile as possible and is in the best condition for laboratory analysis. 4. The specimen should be transferred into a container which is clearly labelled and sent immediately to the laboratory. To ensure that specimen can be tracked and analysed more accurately. 5. Record in the patient’s notes that this specimen has been collected and sent.

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Calculations between units of measurement
Medical calculations are carried out using the metric measurement system however some patients will still refer to the imperial system when they are talking about their temperature, weight, height, fluid intake etc. It is important that the nurse is able to calculate imperial measurement into its metric equivalent so that like-to-like comparisons are carried out. Calculation from Fahrenheit to centigrade As previously discussed temperature measurement is assessed and reported in degrees centigrade. To convert Fahrenheit to centigrade: Subtract 32 from the Fahrenheit reading and multiply the remainder by 5/9 C = (F – 32) x 5/9

Look at the example below then try the following examples yourself. Convert 103ºF to centigrade: 103 – 32 = 71 71 x 5 = 355 355 ÷ 9 = 39.44ºc

Convert 95.4ºF to centigrade

Convert 106.2ºF to centigrade

Convert 82.9ºF to centigrade

Convert 98.6ºF to centigrade

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Calculation from centigrade to Fahrenheit As previously discussed temperature measurement is assessed and reported in degrees centigrade. To convert centigrade to Fahrenheit: Multiply the Fahrenheit measurement by 9/5 then add 32 F = (C x 9/5) + 32

Look at the example below then try the following examples yourself. Convert 36.5ºc to Fahrenheit 36.5 x 9 = 328.5 328.5 ÷ 5 = 65.7 65.7 + 32 = 97.7ºF

Convert 21.7ºc to Fahrenheit

Convert 38.5ºc to Fahrenheit

Convert 35.9ºc to Fahrenheit

Convert 40.3ºc to Fahrenheit

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Measurement of height As previously discussed height measurement is assessed and reported in metres. To convert feet and inches into metres: 1 inch = 2.54cms 12 inches (1 foot) = 30.48cms Look at the example below then try the following examples yourself. A patient who is 5ft 4 inches: 5 foot = 5 x 30.48 cm 4 inch = 4 x 2.54 cm = = 152.40 cm 10.16 cm 162.56 cm divided by 100 = 1.6256m

1

A patient who is 6 ft 3 inches

2

A patient who is 5ft 8 inches

3

A patient who is 3 ft 4 inches

4

A patient who is 2 ft 9 inches

5

A baby who is 1 ft 6 inches

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Measurement of weight As previously discussed weight measurement is assessed and reported in Kilograms. To convert stones and pounds (lb) into Kilograms: 1 stone = 14 pounds 1 pound = 16 ounces 1 Kilogram = 2.2lbs (2lb 3½ ozs) 5 Kilograms = 11lbs Look at the example below then try the following examples yourself A patient who weighs 10 stone 6lb: 10 stone x 14 6 pounds = = 140.00 lb 6.00 lb 146.00 lb divided by 2.2 = 66.36Kg

1

A patient who weighs 11 stone 4 pounds

2

A patient who weighs 17 stone 12 pounds

3

A patient who weighs 9 stone 2 pounds

4

A patient who weighs 5 stone 11 pounds

5

A patient who weighs 25 stone 4 pounds

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It will be unusual for a nurse to be asked to convert Kilograms into imperial measurement. However, when a baby is born many parents like to know the weight in pounds and ounces for their relatives and friends rather than in Kilograms. Therefore to convert Kilograms into pounds and ounces we remember: 1 Kilogram = 2.2lbs (2lb 3½ ozs) (5 Kilograms = 11lbs) 1 stone = 14 pounds 1 pound = 16 ounces Look at the example below then try the following examples yourself. A baby whose birth weight is 3.4Kg: 3.4Kg x 2.2 = 7.48lb Convert 0.48lb to ounces by multiplying by 16 = 7.68 ounces Baby therefore weighs 7lb 8 ounces (to the nearest ounce)

1

A baby whose birth weight is 3.8Kg

2

A baby whose birth weight is 4.2Kg

3

A baby whose birth weight is 2.8Kg

4

A baby whose birth weight is 5.4Kg

5

A baby whose birth weight is 1.9Kg

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Calculations involving decimals, fractions and percentages
Decimals numbers are those which include a decimal point. For example 6.35, 0.748. Decimal numbers are divided into parts or tenths. The number can be on either side of the decimal point and for each decimal space the tenths are positive or negative. Numbers of the LEFT of the decimal point are greater than 1 Numbers of the RIGHT of the decimal point are less than 1 Place value:

111.111
Hundreds Tens Units Tens Hundreds Thousands

The number of decimal places describes the numbers to the right of the decimal point, for example: 6.35 has 2 decimal places (describing 3 tenths and 5 hundredths of 1)

0.748 has 3 decimal places (describing 7 tenths, four hundredths and eight thousandths of 1)

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Calculating multiples of 10 To multiply a decimal by 10, 100, 1,000 etc To multiply number by: 10 100 1,000 10,000 Count the number of zeros after the 1 1 2 3 4 Move the decimal point to the RIGHT this number of times 1 place 2 places 3 places 4 places

Example 3.5 x 10 = 35.0 3.5 x 100 = 350.0 3.5 x 1,000 = 3,500.0 3.5 x 10,000 = 35,000.0

To divide a decimal by 10, 100, 1,000 etc To multiply number by: 10 100 1,000 10,000 Count the number of zeros after the 1 1 2 3 4 Move the decimal point to the LEFT this number of times 1 place 2 places 3 places 4 places

Example 35 ÷ 10 = 3.5 35 ÷ 100 = 0.35 35 ÷ 1,000 = 0.035 35 ÷ 10,000 = 0.0035

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Multiplying decimal numbers Multiplication of decimal numbers is the same as any other multiplication sum apart from the fact that there are decimal points to be considered. Example 5.35 x 5.35 First count the number of places in total there are following the decimal points: 5.35 x 5.35 = 4 places. Carry out your sum: 5.35 5.35 2675 1605 2675 286225 Now replace the decimal point 4 places from the right = 28.6225 Dividing decimal numbers Division of decimal numbers is the same as any other division sum apart from the fact that there are decimal points to be considered. Example 24.32 ÷ 8

3.4 8 24.32

The decimal point in the answer is placed immediately above where it is in the number being divided. = 3.4

When you are dividing decimals by decimals you first have to make the number you are dividing by into a whole number. If this means moving the point one place to the right then you also have to do that in the number being divided. If you have to move the point 2 places in the number you are dividing by, you then have to move the point 2 places in the number being divided and so on. Example 24.32 ÷ 0.8 By moving each decimal point one place to the right the sum then becomes: 34.0 8 243.2
The decimal point in the answer is again placed immediately above where it is in the number being divided. = 34

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Rounding of decimal numbers

Sometimes it is necessary to:

• •

round up round down

a decimal number into a whole number. An example of this would be when working out infusion rate calculations because you cannot give part of a drop when setting an infusion rate. Round down: If the number after the decimal point is 4 or less. For example 24.39 becomes 24 Round up: If the number after the decimal point is 5 or more. For example 24.59 becomes 25
Exception to this rule

If you are calculating drug dosages for children and have any number after a decimal point always round down.

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Try the following decimal calculations yourself. Multiply the following numbers by 10, 100, 1,000 and 10,000

34.5

63.43

125.756

1435.4356

Divide the following numbers by 10, 100, 1,000 and 10,000

34.5

63.43

125.756

1435.4356

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Multiplying decimals

37.5 x 43.5

25.45 x 35.64

365.456 x 355.432

34.435 x 43.43

Dividing decimals

32.48 ÷ 8

32.48 ÷ 0.8

63.84 ÷ 7

63.84 ÷ 0.7

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Fractions

A fraction is part of a whole number. For example if you see the symbol 15 it means that the whole number has been divided into 5 and you are looking for 1 fifth part. In the same way 2 5 means 2 fifth parts of the whole and 3 5 means 3 fifth parts of the whole. The number of parts required or the upper number in the fraction is referred to as the numerator. The division of the whole or the lower number of the fraction is referred to as the denominator. When adding or subtracting fractions it is essential that the denominator is the same so that the ‘whole’ is constant. For example 1 1 - make the denominator the same 2 + 4
3 8

2

4

+ 2

1

4

then add then subtract

= =

3

4

-

1

4

- make the denominator the same

3

8

8

1

8

Try the examples below:

2

3 +

3

4

3

5 +

1

2

3

4 +

5

6

5 3

6 + 8 -

7

8

3 16

5

6 -

1

4

7

8 -

2

3

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When multiplying fractions multiply the top numbers then the bottom.

For example:

3

4 x

7

3 8 = 4

×7= 8

21 32

5

6 x

7

5 8 = 6

×7= 8

35 48

When dividing fractions you invert (turn upside down) the second fraction and then multiply.

For example:

3 8
2 3

÷ ÷

1 2
3 8

becomes

6 3 2 8 x 1 = 8 8 2 16 3 x 3 = 9

or more simply

3

4 7

becomes

or more simply 1 9

Try the examples below:

1 4 2

4 x 6 x 3 x

2 5 3

8 8 8

5 1 4
2
5

6 x 4 6
3
6

1 8

÷ 28 ÷ 8 ÷
3 8

5

÷ 18

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Converting fractions into decimals
To convert a fraction into a decimal you divide the bottom number (the denominator) into the top number (numerator). For example
4 5

becomes

4 divided by 5 = 0.8 5 4.0

Convert the following fractions into decimals.

3

4

3

5

1

4

1

2

7

8

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Percentages
Percent means part of a hundred and is used in health care to indicate quantities. For example oxygen saturation is measured in percent. The patient has an oxygen saturation of 98 percent or 98 parts per 100. The symbol % is used to mean percentage. 98% oxygen saturation. Percentages are useful when comparing results or figures. If we were to say that a clinic has an annual attendance of 5,000 people and 523 get admitted from it each year it is difficult to compare that to other outpatient clinics. However if you change the number to a percentage (11%) it makes the admissions level easier to compare to other clinics. For example:

Clinic
A B C

Number of attendees
5000 11,245 20,657

Number of admissions
523 945 1467

Percentage of admissions
11% 8% 7%

The results above shows that even though clinic A has the least number of admissions from clinic referral its admissions percentage is in fact the highest of the three clinics. To convert a fraction into a percentage you multiply by 100. For example: 3 4

3

4

=

x 100

=

75%

To convert a percentage into a fraction you divide by 100 For example:

30%

=

30 ÷ 100 =

3 10

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To convert a decimal into a percentage you multiply by 100. 0.75 x 100 (remember to multiply by 100 you move the decimal point 2 places to the right). Therefore 0.75 becomes 75%. To convert a percentage into a decimal you divide by 100. 82% divided by 100 (remember when you divide by 100 you move the decimal point 2 places to the left). Therefore 82% becomes 0.82. Try the examples below: Convert the following fractions into percentages:
1 2
3 5 6 8 8 10

Convert the following percentages into fractions: 30% 45% 60% 80%

Convert the following decimals into percentages: 0.20 0.35 0.68 0.94

Convert the following percentages into decimals: 23% 67% 78% 95%

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Some drugs come in different percentage solutions. As they are usually prescribed in either milligram per Kilogram or microgram per Kilogram, the nurse needs to recognise what the % label means.

Examples of drug or fluid calculations using percentages
General formula = what you’ve got 100 x percentage required

For example, if a patient was receiving an IV infusion of 500mL Dextrose and had received 15% over the first hour what would be the quantity infused? 500mL x 15% 100 = (500 ÷ 100) x 15 = 75mLs

Or if the nurse was told that the patient had received 75mLs of solution and what percentage was this of the full 500mL requirement? Infused to this point Total amount prescribed 75mL 500mL x 100

x

100

=

(75 ÷ 500) x 100 = 15%

Try the examples below.
A patient is receiving a blood transfusion 500mL over 6 hours. The infusion is stopped after 2 hours due to a rise in the patient’s temperature. What percentage of the blood has been transfused and what is this amount in millilitres?

What is 35% of 3 litres?

A patient has received 240mL of a 500mL infusion. What percentage of the total have they received?

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The administration of medicines
The publication guidelines for the administration of medicines (current version 1st August 2004) is written by the Nursing and Midwifery Council and can be viewed at www.nmc-uk.org This code of practice gives guidance and advice to nurses at all levels regarding how medication should be prescribed and administered. Minimising errors:

• • • • • • • • •

Take care when reading doses Make sure everything is in the same unit Write out calculations clearly If using formulas check that you have written them properly Write down each step you use

Do not take shortcuts Do not be totally dependent on a calculator – have an estimate prepared
Always double check your calculations

If you have any doubts – STOP and get help

In 1975 the NHS adopted the SI (Systeme International) units of measurement. These units of measurement are used to measure weight, volume and amount and are used in multiples of 1,000. The SI units have prefixes which refer to the multiples or submultiples of 1,000 the measurement contains. For example, with reference to weight the base unit is the gram (g). If you have 1,000g the prefix would be Kilo. 1 Kg = 1,000g If you have 1/1,000g the prefix would be milli. 1 gram = 1,000mg If you have 1/1,000,000 the prefix would be micro. 1 gram = 1,000,000 micrograms If you have 1/1,000,000,000 the prefix would be nano. 1 gram = 1,000,000,000 nanograms

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Symbols are sometimes used instead of the full prefix and these are shown below.

SI prefixes and their symbols: Prefix
Mega Kilo Deci Centi Milli Micro Nano

Symbol
M K d c m
3

Division or multiple of 1
X 1,000,000 X 1,000

+ 10 + 100 + 1,000 + 1,000,000 + 1,000,000,000

n

Abbreviation symbols should not be used when prescribing drugs because a dose of 1,000 times more than required or 1,000 times less than required could have fatal consequences for the patient. This means that the terms milligrams, micrograms and nanograms should be written on the prescription chart in full. If symbols have been used by the doctor always check and recheck the dosage before giving the medication to the patient. When looking at prescribed drugs they will normally be written in grams, milligrams (1x1,000 of a gram) or micrograms (1 x 1,000,000 of a gram). Volume of liquid drugs will be written in Litres or millilitres (1,000 of a Litre). Amount of a drug or chemical will be expressed as a mole [mol], millimole [mmol] (1x1,000 of a mole) or micromole [mcmol] (1x1,000,000 of a mole). When working with or prescribing drugs it is always better to work in whole numbers rather than fractions or decimals. The pharmaceutical industry therefore provides drugs in these smaller denominations to ensure accuracy of dose. It is also preferred that decimal points in drug prescriptions are not used as this can have a confusing effect. For example Paracetamol should be prescribed as 1 gram not 1.0 grams which, if the decimal point is not clearly seen, could be misinterpreted to be 10 grams.

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As a basic guideline:

Tablets – no more than 4 should be given as any one dose (the main exception to this is Prednisolone where 10 tablets may be given at each dose) Liquids – no more than 20mL for any one dose Injections – no more than 10mL for any one dose IV giving sets – infuse 20 drops per mL
Therefore looking at the example given above: if the prescription for Paracetamol had been written as 1.0g and the nurse had read it as 10g that would mean that 20 x 500mg tablets would be required to be given. This is well above the guideline of 4 tablets for any one dose. Therefore the nurse would STOP, check the prescription and get further guidance from another registered practitioner BEFORE proceeding to administer the medication.

Converting units of measurement:
When converting from a large unit to a smaller unit, for example from grams to milligrams, from Litres to millilitres or from moles to millimoles the number is multiplied by 1,000. When converting from a small unit to a larger unit, for example from micrograms to milligrams, from millilitres to Litres or from micromoles to millimoles the number is divided by 1,000. Try the examples below: Convert 0.75 grams to milligrams Convert 7,500 micrograms to milligrams Convert 0.25 Litres to millilitres Convert 500 millilitres to Litres Convert 0.5 mols to millimoles Convert 5,000 micromoles to millimoles

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Common abbreviations b.d. t.i.d q.i.d twice per day three times per day four times per day

mane in the morning nocte in the evening prn as required

Oral medication may be in the form of:

• • •

tablets capsules liquids

Ideally you would have the strength of tablet/capsule for the dose prescribed (e.g 40mg Frusemide prescribed and there is a 40mg Frusemide tablet manufactured). A whole tablet is always preferable to a broken one because, unless the tablet is broken accurately, the dose will not be exact. Tablets that do not have a ‘break bar’ across one side of their surface should never be broken as there is a high risk of inaccurate dosage being given. Capsules should never be opened and their contents divided. When calculating the dose ensure that the prescription strength and the stock strength are the same or convert the units so that you are working in one strength throughout.

Examples of oral medication calculations General formula = dose prescribed dose available = number of tablets/capsules to be given

A patient is prescribed 1gram of paracetamol but they are only available in 500 milligram tablets. How many are required? 1 gram = 1,000 milligrams Therefore: dose prescribed dose available = 1,000milligram 500milligram

= 2 tablets required

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A patient is prescribed Calpol 240mg which is available as a 120mg/5mL syrup. Formula for liquid drug doses = = dose prescribed dose available 240 120 x x 5mL what it’s in = 2 x 5mL

=
Try the following examples: 1.

10mL to be given

A patient is prescribed 500milligrams Amoxycillin 4 times per day. The capsules are only available as 250milligrams. How many capsules would the patient get at each drug round and how many capsules would they receive on a daily basis?

2.

A patient is prescribed Loperamide to assist with an acute diarrhoea episode. They have to take 4 milligrams as a first dose and then 2milligrams after each loose stool up to a maximum of 16 milligrams daily. The capsules are available in a 2milligram strength. How many capsules is the patient to take to start the treatment? How many have they to take after each loose stool? What is the maximum number of capsules allowed in a 24 hour period?

3.

A patient has been prescribed Ibuprofen for relief of pain. They are allowed to take up to 1.2grams per day. If each tablet is 200milligrams in strength how many tablets can they take daily? Ibuprofen is also available as a 400milligram tablet. How many tablets of this strength would be allowed daily?

4.

A toddler is prescribed flucloxacillin 250milligrams. This drug is available in syrup form, 125milligrams in 5millilitres. How many millilitres of syrup should be given to the toddler for each prescribed dose?

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Recording of results
Results, when recorded on the kardex or on a chart must be accurate and time must be taken to ensure that this is the case. Most health boards now use the Early Warning Scoring system to ensure that any deviations from the norm are reported at once. The Early Warning Scoring system is a simple system that can be used at the bedside of the patient and will immediately alert staff to patients whose condition is deteriorating or those who require clinical intervention. The parameters used when calculating an Early Warning Score are the patient’s respiratory rate, pulse, blood pressure, temperature, mental response and urine volume. As discussed earlier the respiratory rate is the one assessment that tended to be overlooked. However, it has been found to be the most sensitive indicator of the patient’s overall well being and for this reason is found at the top of most health board charts to ensure that it is assessed first. The scoring is carried out by the use of different coloured bars on the chart and, if a physiological measurement falls into the coloured boxes, a score is allocated to the result. If the patient has a score of 3 or more when the physiological measurements have been completed then the ward doctor or registrar should be summoned immediately to review the patient’s care. This assessment tool enables nursing staff to summon medical help on an evidence based system and will ensure that the patient’s condition is not put at risk while a junior doctor makes a decision whether to call a senior medical person or not. With the use of this early intervention it has been found that simple interventions such as an increase in oxygen therapy or fluid therapy is enough to prevent further patient deterioration.

Using the chart provided fill in the results below and decide at what times referral should be made to a member of the medical personnel. 2am
Conscious level Temperature Pulse Blood Pressure Respirations Urinary output Asleep 36.5 62 140/86 20

6am
Asleep 37.9 72 166/88 22

10am
Awake 38.2 76 192/96 30 600mls

2pm
Awake 37.7 76 188/96 28 400mls

6pm
Awake 38.3 78 168/92 24

10pm
Drowsy 37.5 74 166/88 22 300mls

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Interpretation of physiological measurement results
The normal ranges of physiological measurements are given below and patient results outwith these parameters should be recorded and reported as soon as possible to a registered practitioner. However, remember that some patients will not have a ‘normal’ baseline due to their medical condition and this has to be taken into consideration when anomalies are recorded and reported.

Respiratory rate (at rest)
Adult Child (aged 5) Baby Peak Flow (normal adult values) 12-18 breaths per minute 25 breaths per minute 30 breaths per minute

MALE
Age / Height 15 25 35 45 55 65 75 1.6m (5’3’’) 485 575 601 590 557 513 466

Peak expiratory Flow Rate in Litres per minute
1.67m (5’6’’) 498 591 618 606 572 527 478 1.75m (5’9’’) 511 608 636 623 588 542 491 1.83m (6’) 524 624 653 640 603 556 503 1.90m (6’3’’) 535 637 666 653 616 567 514

FEMALE
Age / Height 15 25 35 45 55 65 75 1.53m (5’) 385 422 425 412 389 362 334

Peak expiratory Flow Rate in Litres per minute
1.6m (5’3’’) 394 433 436 422 399 371 342 1.67m (5’6’’) 402 441 445 431 407 378 348 1.75m (5’9’’) 411 451 454 440 415 386 355 1.83m (6’) 418 459 463 448 423 393 362

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Oxygen Saturation
The healthy person breathing in air should have an oxygen saturation of 96-99%.

Normal blood pressure levels per age group
Newborn 4 years 6 years 10 years 12 years 16 years Adult 50/27 85/60 95/62 100/65 108/67 118/75 120/80

Normal resting pulse rate per age group
Newborn Infant 2 - 10 years Adolescent Adult 140 - 180 80 - 150 70 - 110 55 - 90 60 - 80

Temperature
Body temperature is not completely constant throughout the day however the average normal temperature for a healthy adult is 36.5ºc - 37.2ºc.

Height
There is no ‘normal height’ for the general population. Height depends on genetic heritage, good diet etc. The reason why it is important to know the height of the patient is so that the ideal weight can be calculated and also the Body Mass Index. Height may also be required to calculate the area of the patient. This measurement is sometimes used when calculating chemotherapy and radiotherapy for patients with a carcinoma.

Weight
There is no ‘normal weight’ for the general population but the weight must be in proportion to the height to maintain a healthy Body Mass Index.

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The height weight chart below covers both men and women. Slim women tend to be towards the lower end of the healthy weight (white) range, whilst men would still look slim at the top end of the healthy weight range. This is because of the differences in body composition between males and females. The light grey area of the chart is overweight while the dark grey area means underweight. Weight in stones

Height in feet/inches

Body Mass Index
Normal = BMI 18.5 - 24.9

Fluid Balance
The normal adult daily intake is 2,500mls. Approximately 500mls is lost insensibly (through breathing, sweating etc) and the urinary output should be approximately 2,000mls.

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Urine testing
When using a urine dipstick the following analysis is carried out:

Blood

No blood should be present in a urine specimen. The presence of blood may indicate, for example, infections of the kidneys and urinary tract, trauma (for example during catheterisation), suspected renal or bladder disease (for example carcinoma).

Urobilinogen The normal level of urobilinogen in urine is 0-17 micromols/L. The presence of an increased amount in urine may be due to liver dysfunction or haemolytic diseases. For example, viral hepatitis, chronic hepatitis, cirrhosis of the liver, infection, poisoning, liver carcinoma or pernicious anaemia.
No bilirubin should be present in a urine specimen. The presence of bilirubin may indicate, for example, hepatitis, cirrhosis of the liver or biliary obstruction. No protein should be present in a urine specimen. The presence of protein may indicate, for example, infection, poisoning, tuberculosis of the kidney, glomerulonephritis. No nitrite should be present in a urine sample. The presence of nitrite would indicate an infection of the urinary tract. No ketones should be present in a urine sample. The presence of ketones may indicate, for example, diabetic ketosis, starvation, metabolic abnormalities during pregnancy.

Bilirubin

Protein

Nitrite

Ketones

Ascorbic Acid

No ascorbic acid should be present in a urine specimen. The presence of ascorbic acid may indicate, for example, the patient receiving vitamin C therapy, the ingestion of fruit juice or fruit in excessive amounts. No glucose should be present in a urine specimen. The presence of glucose may indicate diabetes mellitus. However glycosuria may be seen during pregnancy and may also be present following a meal with a high carbohydrate intake.

Glucose

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pH

The pH value of fresh urine from a healthy person varies between pH 5 and pH 6. The pH should always be measured in fresh urine, since bacterial decomposition may increase the pH to values above 9. pH values are more acid in patients with high fevers, serious diarrhoea and metabolic acidosis (a serious form of diabetes mellitus). pH values are more alkali in patients with urinary tract infections. The normal specific gravity for an adult with a normal food and liquid intake is 1.015-1.025. The specific gravity measures the density of the urine. High fluid intake can reduce the SG to 1.000 and extreme thirst can raise the SG to 1.400. High fluid intake aside, a dilute urine, resulting in a lowered SG may indicate insufficiency of the kidneys and a lowered ability to concentrate the urine, for example in diabetes mellitus and diabetes insipidus and following the use of diuretic drugs. No leucocytes should be present in a urine sample. The presence of leucocytes may indicate infectious diseases of the kidneys and/or urinary tract. For example chronic pyelonephritis, cystitis, urethritis, fungal and trichomonade infections, gonorrhoea, urogenital tuberculosis.

Specific Gravity

Leucocytes

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Factors affecting reliability of physiological results

Environmental factors must be considered when taking physiological measurements from patients. The environment is most likely to interfere with the taking of temperature therefore the surrounding temperature must be considered.
Although oral temperature is very rarely carried out nowadays, when it is, the patient should not have drunk any hot or cold liquids for at least 20 minutes prior to the recording of the temperature or this could have a dramatic effect on the results.

Individual factors must also be considered, for example does the patient have ‘white coat’ syndrome. Physiological measurements, especially blood pressure, can be dramatically raised if the patient is apprehensive and anxious about the recording being taken. Faulty equipment. Equipment should be calibrated and serviced on a regular basis to ensure that abnormal results are not due to poor or faulty equipment. There should be a register in the ward area recording all equipment and when the next service is due.
If a result appears to be very abnormal for the patient always check your findings on another piece of equipment and, if required, get another member of staff to repeat the test to confirm your findings.

Faulty Technique is most likely when students are learning or when new equipment is introduced and staff have not been properly trained in its use. Always recheck abnormal results using another piece of equipment if available, or get an experienced member of staff to confirm your findings.

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Reporting procedures
As a student any deviation from the norm must be immediately notified to your mentor so that they can take the appropriate action. The SEWS chart assists trained staff in that they now have a policy in place which states that if the SEWS score is above a trust specified number they have the authority to contact a senior doctor to get the patient reviewed. This ensures that the patient is reviewed immediately and care is modified to suit the change in condition. All wards have a policy manual and as you move from hospital to hospital on placement it is essential that you read this policy manual to ensure that you are aware of the procedures in place for recording and reporting changes in the condition of the patient. The basic policy will be the same in all areas but procedures will change from placement to placement. It is your responsibility to ensure that you are aware of these procedures and abide by them.

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Formative assessment
1 You read a policy document that states that in the event of a major incident each ward must make 10% of their bed occupancy available for receiving the injured. How many beds would you need to make available in a: 10 bedded ward 30 bedded ward 20 bedded ward 2 Following a review of the major incident policy an amendment has been made. Now each ward must make 20% of their bed occupancy available. How many more beds must you make available in each of the wards? 10 bedded ward 30 bedded ward 20 bedded ward 3 A clinical audit on bed occupancy has shown that your ward is under occupied by an average of 15%. You work on a 20 bedded ward. From the clinical audit findings identify the average bed occupancy of this ward. You are working in a busy 25 bedded admissions unit. You currently have full occupancy. At the start of the shift 5 discharges are planned and two admissions are planned. However 4 emergency admissions are notified during the course of the morning. Will you have enough beds? A patient is prescribed 1 gram of Paracetamol. Each Paracetamol tablet is 500 milligrams. How many tablets would you give? You have to give an injection of 5 milligrams of Diamorphine. Each vial of Diamorphine contains 10 milligrams in 1mL. How much of the Diamorphine would you draw up from the vial for the injection? A patient is prescribed 20 milligrams Senokot liquid. The label on the bottle states that each 5mLs contains 10 milligrams. How many mLs of the Senokot liquid would you dispense?

4

5

6

7

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8

A patient is prescribed an injection of 10 micrograms of Morphine. Each vial contains 10 milligrams in 1mL. What would you do? An elderly gentleman who has smoked since he was a teenager now has Ischaemic Heart Disease. You are told his cardiac output is 20% less than someone his age who is healthy. Express this reduction in cardiac output as a fraction. An intravenous infusion of 0.9% Saline 500mLs is to be given over 4 hours. What would the infusion rate be? Express 1,000 micrograms in milligrams. A patient has been prescribed Captopril 12.5 milligrams. The tablets supplied are 25 milligrams and are scored. How would you dispense this medication? Express 3 grams as milligrams. An elderly patient, who is very agitated at night, has been prescribed 50 milligrams of Chlorpromazine at 10pm. The Chlorpromazine supplied is in liquid form, 5 milligrams per mL. How much of the liquid would you dispense? The patient above has also been prescribed a prn (if required) dose of 25 milligrams 4 hourly, with a sub note ‘ no more than 100 milligrams of Chlorpromazine in 24 hours’. Having given the 10pm dose, identify the maximum amount of times you can dispense the prn dose in 24 hours should the patient remain agitated. A young pregnant woman has gained too much weight during her pregnancy. You are told she has gained a further 60% of her body weight. Express this weight gain as a fraction. One Litre of Hartmann’s solution is being infused at 125mLs per hour. What time span has the infusion been prescribed over? Round off 0.746 to two decimal places. Round off 87.713342 to three decimal places.

9

10

11 12

13 14

15

16

17

18 19

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20 21 22 23

Multiply: 0.32 x 0.04. Multiply: 3.2 x 0.4 Multiply: 0.35 x 10 Divide:
1

4

÷

1

8

24

Divide:

1

3

÷

1

2

25

Divide: 0.0035 ÷ 100

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Section 4: Assessment guidelines
For this Unit, Outcomes 1 and 2 will be submitted in the form of a Skills Booklet showing your understanding and practice of practical techniques and their recording and reporting within your placement setting. This Skills Booklet must be signed by your mentor prior to being submitted for marking. Outcome 3 will be a closed book assessment and is 20 multiple choice questions based on arithmetical calculations. You will be required to achieve 100% to pass this assessment.

How and where you will be assessed:
Evidence of your practical ability will be assessed by your mentor on placement and they will sign your Skills Booklet to confirm your competence in the areas to be assessed.

When you will be assessed
The closed book calculations assessment will be held on week 17 of this Unit

If reassessment is required
Any remediation required will be carried out on week 18 of this Unit.

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Section 5: References and additional resources
The following websites provide a useful resource for calculations: www.nes.scot.nhs.uk/nursing/ www.nes.scot.nhs.uk/syringe-driver www.accd.edu/sac/nursing/math/mathindex2.html The following publication also provide a useful resource: Lapham and Agar, Drug Calculations for Nurses, ISBN 0-3408-1028-9 Brown and Mulholland, Drug Calculations: Process and Problems for Clinical Practice ISBN 0-3230-4576-6 Lapham, Drug Calculations for Nurses: A Step by Step approach ISBN 0-3406-0479-4

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