Ch 45. Agents Affecting the Volume and Ion Content of Body Fluids Flashcards
What is the decrease in total body water?
vol contraction
What is the increase in total body water?
volume expansion
What are the causes of isotonic contraction?
vomiting, diarrhea, kidney disease, and misuse of diuretics
What is isotonic contraction?
Volume contraction in which Na and H2O are lost in isotonic proportions
Decrease in total volume but no change in osmolarity
Treatment for isotonic contraction?
fluids isotonic to plasma
.9% NS
give fluids slowly
What is hypertonic contraction?
- loss of water exceeds loss of Na
- reduced ECF volume and increase in osmolarity
What are the causes of hypertonic contraction?
- excessive sweating, osmotic diuresis.
- secondary to extensive burns or CNS disorders that interfere with thirst.
Treatment for hypertonic contraction?
hypotonic fluids (.45% NaCl) or fluids that contain no solutes
intial therapy: drink water
What is hypotonic contraction?
= loss of Na exceeds loss of H2O
= both volume and osmorality of ECF are reduced
Causes of hypotonic contraction?
excessive loss of Na through kidney
Tx for hypotonic contraction?
Mild: infusing isotonic NaCl solution for injection
Severe: hypertonic solution 3% NaCl
What is the cause of volume expansion?
- overdose with therapeutic fluids
- disease states
What are acid-base disturbances?
- respiratory alkalosis
- respiratory acidosis
- metabolic alkalosis
- metabolic acidosis
Tx for volume expansion
diuretics and agents used for heart failure
What is the cause of respiratory alkalosis?
hyperventilation causes decrease in CO2
Treatment for respiratory alkalosis?
Mild: none
Severe: rebreathe CO2 laden expired breath
What is the cause of respiratory acidosis?
retention of CO2 secondary to hypoventilation
Tx for respiratory acidosis?
- correction of respiratory impairment
- infusion of NaHCO3 if severe