Fundamentals II Exam 3 Study Guide
Chapter 41 – Fluid, Electrolyte, and Acid-Base Balance

1. Extracellular Fluid (ECF): Located OUTSIDE cells. Makes up about 1/3 total body H2O in adults. Two major divisions: Intravascular Fluid (plasma) and Interstitial Fluid (btw. cells and outside blood vessels. Minor division: Transcellular fluid – cerebrospinal, pleural, peritoneal and synovial fluids (all excreted by epithelial cells).
Intracellular Fluid (ICF): Located INSIDE cells. Makes up about 2/3 total body H2O in adults.

2. ECV Deficit: BUN >25 mg/dl Insufficient isotonic fluid in the extracellular compartments. Output of isotonic fluid exceeds intake of sodium-containing fluid.
Signs and Symptoms – sudden weight loss, postural hypotension, tachycardia, thready pulse, neck veins flat or collapsing with inhalation when supine, dry mucous membranes, poor skin turgor, restlessness, clammy skin, hypovolemic shock.

ECV Excess: BUN <10 mg/dl Too much isotonic fluid in the extracellular compartments. Intake of sodium-containing isotonic fluid has exceeded fluid output. (When you eat too much salt and don’t drink enough H2O and you get bloated.)

Signs and Symptoms – Sudden weight gain, edema, neck veins full when upright or semi upright, crackles in dependent portions of lung, pulmonary edema.

3. Isotonic: A fluid with the same concentration of nonpermeant particles as blood.
Ex. - 0.9% sodium chloride, commonly called normal saline (NS), and lactated Ringer's (LR). Isotonic solutions have an electrolyte content of less than 250 mEq/L

Hypertonic: A fluid more concentrated than normal blood.
Ex. - 5% dextrose (sugar) and 0.45% sodium chloride is an example of a hypertonic solution - so is a solution of 5% dextrose and 0.9% sodium chloride. Solutions with an electrolyte content of 375 mEq/L or more are considered hypertonic.

Hypotonic: A fluid more dilute than normal blood. Ex. - 0.45% sodium chloride (0.45% NS), commonly called half normal saline. Total Calcium Ca | 8.4-10.5 mg/dL | | ---Ionized Calcium | 4.5-5.3 mg/dL | | Sodium Na | 136-145mEq/L | | Potassium K | 3.5-5.0 mEq/L | | | Magnesium Mg | 1.5-2.5 mEq/L | 1. Normal Electrolyte Levels:

2. Root word: NATREMIA – means sodium, so hyper=too much salt, hypo=not enough salt.

Hypernatremia: H2O deficit – Hyperosmolar Imbalance – Hypertonic Body Fluids
Loss of relatively more H2O than Na
Signs and Symptoms- Extreme thirst, dry and flushed skin, postural hypotension, fever, restlessness, confusion, agitation, coma or seizures if severe or develops rapidly
Serum Na >145mEq/L
Causes: Diabetes Insipidus, Greatly increased insensible perspiration and H2O output without increased H2O intake

Hyponatremia: H2O Excess, H2O Intoxication – Hypoosmolar Imbalance – Hypotonic Body Fluids
Gain of relatively more H2O than Na
Signs and Symptoms- Apprehension, nausea, vomiting, headaches, decreased consciousness, confusion, lethargy, muscle weakness, seizures and coma if develops rapidly or is severe.
Serum Na<135mEq/L
Causes: Excessive ADH, too much IV 5% dextrose given, forced excessive H2O drinking.

3. Hypercalcemia: High Serum Calcium Level
Signs and Symptoms – Anorexia, nausea and vomiting, constipation, fatigue, diminished reflexes, lethargy, confusion, decreased consciousness, cardiac dysrhythmias, possible flank pain.
Total Serum Ca>10.5 mg/dL
Causes: Prolonged immobilization, hyperparathyroidism, bone tumors, use of thiazide diuretics

Hypocalcemia: Low Serum Calcium Level
Signs and Symptoms – Positive Chvostek and Trousseau, numbness and tingling in fingers and around mouth, muscle cramping, seizures, laryngospasm, cardiac dysrhythmias
Total Serum Ca<8.4 mg/dL
Causes: Diet deficient in Ca or vitamin D, chronic diarrhea, laxative misuse, hypoparathyroidism,

4. Hypermagnesemia: High Serum Magnesium Level
Signs and Symptoms- Lethargy, hypoactive deep tendon reflexes, bradycardia, flushing and warmth. If sever, decreased respirations and cardiac arrest.
Serum Mg>2.5mEq/dL
Causes: Excessive use of Mg containing antacids and laxatives, end-stage renal disease, adrenal insufficiency

Hypomagnesemia: Low Serum Magnesium Level
Sign and Symptoms – Positive Chvostek and Trousseau, hyperactive deep tendon reflexes, insomnia, tachycardia, cardiac dysrhythmias, signs of toxic Dig levels when levels are normal
Serum Mg <1.5mEq/dL
Causes: Malnutrition, chronic alcoholism, chronic diarrhea, laxative misuse, use of thiazide or loop diuretics, aldosterone excess

5. Acid-Base Imbalances

Respiratory Acidosis: Excess Carbonic Acid caused by Alveolar Hypoventilation
Signs and Symptoms – Headache, light-headedness, decrease consciousness, lethargy, warm, flushed skin, muscle twitching
PH <7.35
Causes: COPD (Type B or end-stage Type A), Pneumonia, severe acute asthma episode, airway obstruction, respiratory weakness or fatigue, drug overdose with respiratory depressant, central sleep apnea Respiratory Alkalosis: Deficient Carbonic Acid caused by Alveolar Hyperventilation
Signs and Symptoms - Increased rate and depth of respirations, light-headedness, excitement and confusion possibly followed by decreased level of consciousness. PH >7.45
Causes: Hypoxemia, acute pain, psychological distress, prolonged sobbing, head injury, meningitis, gram-negative sepsis, salicylate overdose.

Metabolic Acidosis: Excessive Metabolic Acids
Signs and Symptoms- Decreased level of consciousness, abdominal pain, and compensatory hyperventilation (increased rate and depth of respirations).
PH <7.35
Causes: Ketoacidosis from alcoholism, starvation or diabetes, severe hyperthyroidism, burns, severe infection, diarrhea.

Metabolic Alkalosis: Deficient Metabolic Acids
Signs and Symptoms – light headedness, numbness and tingling of fingers, toes, or area around mouth, excitement and confusion possibly followed by decreased level of consciousness.
PH >7.45
Causes: Increase of bicarb, Massive blood transfusion, mild or moderate ECV deficit, Excessive or prolonged vomiting, prolonged gastric suctioning, hypokalemia, excessive aldosterone.

HINT: If PH and PaCO2 are both up or both down, it’s Metabolic. If opposite, it’s Respiratory.

6. ABG Values

pH | 7.35-7.45 | Measure of how acidic or alkaline the blood is. | PaO2 | 80-100 | Partial pressure of oxygen and how well gas exchange is occurring in alveoli of lungs. Values below normal indicate poor oxygenation in the blood. | PaCO2 | 35-45 mm HG (4.7-6 kPa) | Partial pressure of Carbon Dioxide. A measure of how well lungs are excreting CO2 produced by the cells. Increased=CO2 accumulation in the blood. Decreased=excessive CO2 excretion | HCO3− | 22–26 mEq/L | Concentration of base (alkaline) A measure of how well kidneys are excreting metabolic acids. | SaO2 | 95-100% | Oxygen saturation. The % of hemoglobin that is carrying as much oxygen as possible. | Base excess | −2 to +2 mmol/L | Observed buffering capacity-Normal buffering capacity. A measure of how well blood buffers are managing metabolic acids. |

7. Nursing measures for restriction of fluids:

Patients with hyponatremia usually have restricted water intake. Patients with severe ECV excess may have sodium AND fluid restriction. Make sure pt. understands the reason for restrictions and that family and visitors know the amt. of fluid permitted orally.
(See p. 904, bottom left paragraph.)

8. Clinical Dehydration:
There are 2 types of dehydration, namely water loss dehydration (hyperosmolar, due either to increased sodium or glucose) and salt and water loss dehydration (hyponatremia).

Chapter 40 – Oxygenation

1. Respiratory and Cardiac A&P: Read pages 822-825

2. Steps to oxygenation:

Ventilation – Mechanical process of moving air in and out of lungs.
Perfusion – The ability of the cardiovascular system to pump oxygenated blood into the tissues and return deoxygenated blood to the lungs.
Diffusion – Moves the respiratory gases from one area to another.

3. Mobilizing respiratory secretions:
See pages 842-845
Hydration, humidification, nebulization, coughing and CPT (Chest Physiotherapy) – Includes postural drainage, chest percussion and vibration. CPT is followed by suctioning of the secretions if greater than 30mL of sputum per day or evidence of atelectasis upon chest x-ray.

Coughing is our body’s natural way – Teach patients to cough/huff: Take a nice deep breath, tighten up your belly and cough - should be able to blow a tissue/cotton ball off your hand w/ the cough.

4. Chest tube care – Nursing Measures:
p. 850 & 869
1. Auscultate for signs of respiratory distress (decreased breath sounds, cyanosis, and asymmetrical chest movements)
2. Obtain baseline vitals, level of cognition and SpO2.
3. Assess HGB and HCT levels. (See chart below)
4. Observe dressing and site surrounding insertion area. Apply gloves if drainage is present. The chest tube should be secured to the chest wall. Keep the suction0cintrol chamber filled with sterile H2O to the prescribed level. Mark the level outside the collection chamber every shift. Report any cloudy or bloody drainage. Do not let tubing kink or loop. Encourage pt. to cough, deep breathe and use incentive spirometer. Make sure pt. is frequently ambulated or changes positions unless contraindicated. Clamping of tube is contraindicated when ambulating or transporting. Handle drainage unit carefully and keep it below the pt.’s chest. If tubing disconnects, instruct pt. to exhale as much as possible and to cough to remove pleural space air. Temporarily reestablish a water seal by immersing open end of tube in sterile H2O.

| Men | Women | RBC | 4.32-5.72 trillion cells/L | 3.90-5.03 trillion cells/L | HGB | 13.5-17.5 grams/dL | 12.0-15.5 grams/dL | HCT | 38.8-50% | 34.9-44.5% | WBC | 3.5-10.5 billion cells/L | Platelets | 150-450 billion/L |

5. Trach Care & Suctioning:
See p. 847, Box 40-9

6. Terms to know:

Retraction - medical term for when the area between the ribs and in the neck sinks in when a person with asthma attempts to inhale. Retractions are a sign someone is working hard to breathe.

Stridor - a harsh vibrating noise when breathing, caused by obstruction of the windpipe or larynx.

Dyspnea – difficult or labored breathing

7. Causes of Hypoxia : (inadequate tissue oxygenation)

a. Decreased HGB level and lowered oxygen carrying capacity of the blood. b. Diminished concentration of inspired oxygen which occurs at high altitudes. c. Inability of tissues to extract oxygen from blood. As with cyanide poisoning d. Decreased diffusion of oxygen from the alveoli to the blood, as in pneumonia. e. Poor tissue perfusion, as with shock. f. Impaired ventilation, as with multiple rib fractures or chest trauma.

8. Oxygen therapies:
See p. 851, Table 40-7 (Remember she said something about knowing the %’s also.)

9. Respiratory Alterations: p. 826-827 | Assessment | Signs/Symptoms | Hypoxia | PaCO2 SHOULD be btw. 35-45 mmHg PaO2 80-100 mmHgO2 Sat above 95 | Apprehension, restlessness, inability to concentrate, dizziness, decreased level of consciousness, appears both fatigued AND agitated, increased pulse rate and depth of respirations. | Hyperventilation | | Rapid respirations, sighing breaths, numbness and tingling of hands/feet, light-headedness, loss of consciousness. | Hypoventilation | | Mental status changes, dysrhythmias, potential cardiac arrest | Cyanosis | | Blue discoloration of skin caused by desaturated HGB in the capillaries (late sign of Hypoxia) |

10. Myocardial Infarction (MI): p. 828 – top rt. paragraph
Also called a heart attack – results from sudden decrease in coronary blood flow or increase in oxygen demand without adequate coronary perfusion. Crushing, squeezing, stabbing pain, may radiate and last more than 20 minutes.

11. Angina: p. 828, bottom left
Transient imbalance between myocardial oxygen supply and demand. Chest pain that is aching, sharp, tingling, or burning or feels like pressure. Pain may radiate and persist for 3-5 minutes, often follows heavy meals, exercise, or stress. (activities that increase myocardial oxygen demand.) Right Side Heart Failure | Impaired functioning of rt. Ventricle. Results from pulmonary disease or long term left Side failure. * Weight gain, distended neck veins, hepatomegaly, splenomegaly, dependent peripheral edema. | Left side Heart Failure | Decreased function of the left ventricle resulting in decreased cardiac output. * Crackles in bases of lungs, hypoxia, shortness of breath on exertion, cough, paroxysmal nocturnal dyspnea. |