Fluid&Electrolytes

Question 1

What do isotonic solutions do?

Answer 1

• Expand intravascular volume–> the amount of water transported into the cell is equal to the amount of water transported out of the cell.
• Usually 0.9% NaCl (NS)
• or, Lactated Ringers (a balanced electrolyte solution
• 5% dextrose in water

Question 2

What do Hypertonic solutions do?

Answer 2

• Draw fluid from cells
• The cell shrinks because water is reabsorbed out of the cell.
• solute concentration outside of the cell is higher than inside the cell

Question 3

What do hypotonic solutions do?

Answer 3

• Shift fluid into cells
• the cell inflates and eventually will burst
• the solute concentration inside the cell is higher than outside the cell.

Question 4

What is Respiratory Acidosis?

Answer 4

• Excessive carbonic acid caused by alveolar hypoventilation. Decreased ventilation causes increased blood CO2 and low pH.
• Causes:
  1. Impaired Gas Exchange–> Type B COPD, emphysema, pneumonia, airway obstruction
  2. Impaired Neurological Fx-> Respiratory muscle weakness or paralysis from hypokalemia or neuro dysfunction. Resp. failure. Chest injury.
  3. Dysfunction of brainstem respiratory control–> Drug over dose with resp. depressant. Central sleep apnea.

Question 5

What are the signs and symptoms of respiratory acidosis?

Answer 5

• Headache, lightheaded, decreased level of consciousness (confusion, lethargy, coma),
• Cardiac Dysrythmia (life threatening)
• warm, flushed skin
• muscle twitching

Question 6

What are the lab finding for blood pH in respiratory acidosis?

Answer 6

pH less than 7.35

Question 7

What is respiratory alkalosis?

Answer 7

• Increased respiration elevates blood pH causing hyperventilation
• Deficent carbonic acid caused by alveolar hyperventilation
• Causes:
  1. hypoxemia
  2. acute pain
  3. anxiety, social distress

Question 8

What are signs and symptoms of respiratory alkalosis?

Answer 8

• increased rate and depth of respirations
• Light headedness
• numbness and tingling of extremities
• excitement and confusion possibly followed by decreased level of consciousness,
• Cardiac Dysrythmia (life threatening)

Question 9

What is Metabolic Acidosis?

Answer 9

• Excessive metabolic acids
• body produces too much acid or kidneys arent removing enough acid
• Causes:
  1. Ketoacidosis (diabetes, starvation, alcoholism)
  2. Hypermetabolic state (severe hyperthryroid, burns, severe infection
  3. Oliguric renal disease
  4. circulatory shock
  or caused by a decrease in Bases:
  1. diarrhea
  2. pancreatic fistula
  3. renal tubular acidosis

Question 10

What is metabolic acidosis?

Answer 10

• Deficient metabolic acids
• low hydrogen ions, high pH
• Due to decrease in metabolic acid (excessive/prolonged vomiting, prolonged gastric suctioning, hypokalemia, excess aldosterone)
• or due to increase of base

Question 11

Hyponatremia

Answer 11

• sodium level less than 136 mEq/L
• Net gain of water or loss of sodium rich fluids
• Hyponatremia delays depolarization of membrane
• water moves from ECF to ICF, so cell swells
• causes coma, seizure, respiratory arrest, muscle weakness, confusion, decreased consciousness
• created by the gain of relatively more water than salt (excessive ADH, forced water drinking, excessive IV admin., tap water enema, using hypotonic irrigating solution), or caused by the loss of more salt than water (renal salt wasting disease, replacement of large body fluid output-diarrhea, vomiting, gastric suction.

Question 12

Hypernatremia

Answer 12

• Water deficit
• serum sodium level greater than 145 mEq/L
• electrolyte imbalance–> neuro, endocrine, cardiac disturbances
• waters moves out of cells and they dehydrate
• extreme thirst, dry and flushed skin, postural hypotension, fever, coma, seizures

Question 13

Hyperkalemia

Answer 13

• serum potassium greater than 5.0 mEq/l
• increased intake of K, movement of K out of cells, or inadequate renal fx
• cardiac arrthymia and cardia arrest

Question 14

Hypokalemia

Answer 14

• Serum potassium below 3.5 mEq/L

- potassium lose from body or movement of K into cells.

Question 15

Extracellular fluid volume deficit

Answer 15

• sodium and water intake is less than output
• due to –> increased renal output, decreased oral intake, increased GI output, loss of blood or plasma, massive sweating
• Signs/sx= sudden weight loss overnight, thready pulse, neck veins flat or collapse, hypotension, clammy skin, hypovolemic shock (life threatening)
• lab= increased hematocrit, Bun above 25 mg/dl

Question 16

Extracellular fluid volume Excess

Answer 16

• sodium and water intake is greater than output, causing isotonic gain
• excessive intake of salty food, excessive admin of sodium isotonic parenteral fluid
• decreased renal output
• signs/sx= Sudden weight gain overnight, edema in dependent areas, neck veins full when upright, crackles, pulmonary edema
• lab findings= decreased hematocrit, bun lower than 10 mg/dl