Fluid Gains And Losses Flashcards
You lose about–mL of water each day by?
2,500
Urine feces insensible perspiration
Insensible perspiration
The gradual movement of water across the epithelia of the skin and lungs
Sensible perspiration
The secretory activities of the sweat glands.
Maximum perspiration rates: 4 liters per hour
Water gain amount
40 mL/kg
You should obtain water through
Eating- 1000mL
Drinking- 1200mL
Metabolic generation- 300 mL
Metabolic generation
Is the production of water within cells, primarily as a result of oxidative phosphorylation in mitochondria.
Cells breaking down 1 g of lipids yields
1.7 mL of water
Proteins= 0.41mL
Carbohydrates = 0.55 mL
When you lose water but retain electrolytes
The osmotic concentration of the ECF increase
Then: osmosis then moves water out of ICF and into ECF until both are isotonic
If fluid imbalance continue a significant decrease in
Plasma volume and blood pressure occurs and shock may occur.
Cause of hypernaturemia
Excessive sweating
Inadequate water consumption
Repeated vomiting and diarrhea
Homeostatic responses to hypernaturemia
Physiological mechanisms -secretion of ADH and renin
Behavioral- increase fluid intake
Clinical- given hypotonic fluids
When drinking tap water or given hypotonic solution–
The ECF volume increases but becomes hypotonic with respect to the ICF.
What happens when The ECF volume increases but becomes hypotonic with respect to the ICF.
A fluid shift occurs, and the volume of the ICF increases.
After the shift, both will have slightly larger volumes and slightly lower osmotic concentrations than originally.
How is the situation corrected? After the shift, both will have slightly larger volumes and slightly lower osmotic concentrations than originally
The decreased plasma osmotic concentration depresses the secretion of ADH; which discourages water intake and water loss in urine.
If this situation is not corrected: After the shift, both will have slightly larger volumes and slightly lower osmotic concentrations than originally
Clinical problems will develop as water shifts into the intracellular fluid, distorting cells, changing the solute concentrations around enzymes, and disrupting cell functions.
The condition of hyperhydration or water excess can be caused by
- Drinking a large volume of water or the infusion of a hypotonic solution
- An inability to eliminate excess water in urine, due to chronic renal failure, heart failure, cirrohsis, etc
- Endocrine disorders such as excessive ADH production
The most obvious sign of overhydration
Abnormally low sodium ion concentrations –hyponatremia
The reduction in Na concentrations in the ECF leads to
A fluid shift into the ICF
Treatment of severe overhydration
Diuretics
Infusing a concentrated salt solution that promotes a fluid shift from the ICF to the ECF and returns Na concentrations to near normal
The condition of hyperhydration or water excess can be caused by
- Drinking a large volume of water or the infusion of a hypotonic solution
- An inability to eliminate excess water in urine, due to chronic renal failure, heart failure, cirrohsis, etc
- Endocrine disorders such as excessive ADH production
The most obvious sign of overhydration
Abnormally low sodium ion concentrations –hyponatremia
The reduction in Na concentrations in the ECF leads to
A fluid shift into the ICF
Treatment of severe overhydration
Diuretics
Infusing a concentrated salt solution that promotes a fluid shift from the ICF to the ECF and returns Na concentrations to near normal
