Body Fluid Compartments Flashcards
Volume contraction vs expansion?
- Contraction is a decrease in volume
- Expansion is increase in volume
Iso, hypo, hyper osomotic?
- Isosmotic means no change in osmolarity
- Hyposmotic means body fluid osmolarity is decreased
- Hyperosmotic means body fluid osmolarity is increased
What makes up ECF?
- Plasma 20%
- Interstitial fluid 80%
What is 60-40-20 rule?
- 60% of body weight is water
- 40% of body water is intracellular fluid
- 20% body water is ECF
What is the only fluid that can be directed acted on to control volume and compositon?
- Plasma
- A change in plasma regulates the entire ECF
What electrolytes are found in the ECF vs intracellular fluid?
Plasma/Interstitial fluid:
- Na greater amouont than ICF
- K
- Cl
- Bicarb
- (no proteins in interstitial fluid)
ICF:
- Na
- K greater amount than ECF
- Phosphate
- Proteins
What is typical body osmolarity?
290 mOsm
Hypertonic cellular environment will cause cells to ___.
- Hypertonic cellular environment will cause cells to shrink as there will be a net movement of water out of the cell
Hypotonic cellular environment will cause a cell to ____
Hypotonic cellular environment will cause a cell to swell due to a rush of fluid into the cell
What are the four hormonal mechanisms to balance fluid compartments?
- Renal sympathetics
- RAAS
- Vasopressin
- Natriuretic peptide
Activation of what receptor will cause release of renin?
B1 adrenergic
What four things can cause releasae of ADH?
- Angiotensin II
- Atrial receptors in presence of low preload
- Increased osmolality of blood
- Sympathetic nervous activation
What does ANP do?
- Secreted in response to excessive preload of attia and ventricles
- Induces arteriolar dilation decrreasing TPR
- Increases fluid loss to decrease preload
- Inhibits renin
What does ANP do to ADH?
Inhibits its secretion and actions
Patient comes into ER soaked in sweat and light headed and dizzy. States they haven’t drank water the entire 90 degree sunny day they were working outside. What is happening to him regarding body fluid?
- Fluid is shifting from Intracellular to extracellular
- The fluid the cells are sitting in is now hypertonic and to balance out the fluid will leave the cells causing shrinkage
- This increases osmolarity in both compartments and decreases volume of both