Card Set Information
what % of mass in male is water
what % of mass in females is water
what % of mass in infants and children is water
vol of water healthy young male
intracellular fluid in male
extracellular fluid in male
plasma is part of _____ fluid
plasma water of ECF
hormones and nerves play a part in
control of volume and osmolality
control of volume and osmolality is influenced by
hormones and nerves
how many types of subjects and what are they
what did the control subject consume?
consumed no fluid during the class
what did the water subject consume?
drank 20mL of water/kg
what did the saline subject consume?
drank 7mL of 0.9% NaCl solution/kg
what did the urea subject consume?
drank 20mL of 1.8% urea solution/kg
what did the the water + ADH subject consume
drank 20mL of water/kg followed immediately by a dose of lysine vasopressin (ADH) by nasal instillation
what was the subject procedure
consumed test solution over 15-20min period
urine was collected every 30mins
urine vol was measured in
osmolality was determined by
freezing point depression
osmolality results were expressed in
In class, asked to plot ___ & ___ as a function of ______
how long did the test run for
how to calculate for osmolar excretion per 30mins?
urine flow * osmolality
what is the osmolality of 0.9% saline solution
what is the osmolality of 1.8% urea solution
is 0.9% saline isotonic and why
yes. not net mvt of water
is 1.8% urea isotonic and why
no, it is hypotonic. urea moves down conc grad and brings urea and water into cell, causing it to swell
if a cell is in a hypotonic solution, the cell will
if a cell is in a hypertonic solution, the cell will
is 0.9% saline iosmotic
what is iosmotic
having the same pressure
does 0.9% saline go into ICF?
why were subjects who drank 0.9% saline only given 7mL/kg instead of 20mL/kg?
gives same ECF expansion as saline only goes into ECF
what is effect of drinking 20ml/kg of water on urine flow rate and osmolality
dramati incr in flow rate
decr in osmolality
which solution produced similar urine flow rate to that of the water load and what was different
water has lower osmolality; urea has higher osmolality
urea needs to be excreted in urine=active osmolality increasehehe
why urea has greater flow rate than saline
urea is hypotonic = reduces ADH = not reabs from cd in kidneys
saline = isotonic = water doesnt enter cell = osmoreceptors not active
did urea or saline have greater flow rate?
which soln had greatest osmolar excretion + why?
active urea excretion
was diuresis due to vol expansion or dilution of osmolality or both? why?
mainly water caused osmolality dilution
smaller effect detected by osmoreceptors
which osmoreceptors detect change and where are they located
if osmoreceptor swells, effect is?
ADH prodn switched off
what is effect of ADH
mechanism via water loading that causes diuresis are:
1 stim of osmoreceptors = ADH inhibition
2 incr in ECF vol = incr urine produced
If water transfused into plasma, where does it go?
If normal saline transfused into plasma, where does it go?
all in ECF
If urea transfused into plasma, where does it go?
ECF and ICF
If 5.5% mannitol transfused into plasma, where does it go?
some may go into ICF
If plasma transfused into plasma, where does it go?
stays in vascular compartment
If 10% albumin and 0.9%saline transfused into plasma, where does it go?
may have slow turnover to ECF
If blood transfused into plasma, where does it go?
If 5.4% glucose transfused into plasma, where does it go?
initially into ECF
insulin required to enter ICF
how to calculate osmolality
osmolality of plasma * old vol/new vol
calculating osmolality with changes in salt conc
[(orig vol*orig osmolality)+(new vol added*osmolality in it)]/total vol