Body fluid compartments Flashcards
What are 2 examples of daily intake of water?
Oral intake
Synthesized by body (oxidation of carbohydrates).
What are 4 examples of loss of body water?
Insensible loss.
Sweat loss.
Loss in feces.
Loss by kidneys.
What percent of total body weight is typically water in a 70kg man?
60%
What are examples of transcellular fluids in the body?
Synovial.
Peritoneal
Pericardial
Intraocular.
Why does there tend to be more cations in the plasma?
Donnan Effect.
Fluid distribution between interstitial and plasma is controlled by what two things?
Hydrostatic and colloid osmotic forces across the capillary membrane.
Fluid distribution between intracellular and extraceullar compartments is controlled by what mechanism?
It is determined mainly by the osmotic effect of smaller solutes (especially sodium and chloride.)
What is the rate of osmosis?
The rate of diffusion of water across a membrane.
T/F: Osmole is the term that refers to the # of particles in solution?
True
Osmolality formula?
Osmoles/kg of water.
Osmolarity formula?
Osmoles/liter of solution (easier to express this way).
T/F Van Hoff’s Law says that osmotic pressure of a solution is inversely proportional to the concentration of osmotically active particles
False; it is proportional
A 1 mOsm gradient provides how much osmotic pressure?
19.3 mmHg
What percentage of total osmolarity in the interstitial fluid and plasma is due to sodium and chloride ions?
80%
What are 4 conditions that cause hyponatremia?
Diarrhea/vomitting.
Diuretic abuse.
Addison’s disease.
Excess water retention (ADH).
What are 4 conditions that cause hypernatremia?
Lack of ADH.
Diabetes insipidus.
Dehydration.
Aldosterone secretion.
How does Addison’s disease cause a Na+ disturbance?
Results in decreased secretion of aldosterone which causes the kidney to not be able to reabsorb sodium.
Primary loss of water from the extracellular fluid results in what two things?
Hypernatremia and dehydration.
What is nephogenic diabetes insipidus?
A condition where the kidneys cannot not respond to antidiuretic hormone.
Hypernatremia stimulates what two things which help protect the body from large increase in plasma and extracellular fluid sodium?
Intense thirst and secretion of ADH
In what compartment does edema typically take place?
Extracellular fluid compartment.
What are the two general causes of extracellular edema?
- Abnormal leakage from plasma. 2. Lymphatic failure to return fluids to blood
What three things cause abnormal leakage from plasma?
- increase capillary filtration coefficient.
- Increased capillary hydostatic pressure.
- Decrease plasma colloid osmotic pressure.
One of the most important causes of decreased plasma protein concentration is loss of proteins in the urine in certain kidney diseases, a condition referred to as what?
Nephrotic syndrome.
