Fluid, Blood, Coagulation Flashcards
(93 cards)
Describe the distribution of body water
60% of TBW = 42 L
60/40/20 (15/5)
40% = intracellular
20% = extracellular
15% = interstitial
5% = plasma
What populations tend to have a greater percentage of TBW by weight?
neonates have the most
women, elderly, obese have the least
What are the 2 most important determinants of fluid transfer between capillaries and interstitial space?
starling forces
glycocalyx
Net filtration pressure
(Pc - Pif) - (iic - iiif)
<0 = reabsorption
> 0 = filtration
What is the glycocalyx - what disrupts it?
forms a protective layer on the interior wall of the blood vessel. it has anticoagulant properties. it is the gatekeeper.
DM, sepsis, ischemia, vascular surgery all disrupt it
how is lymph returned to the systemic circulation?
via thoracic duct at the juncture of the IJ and subclavian vein
what is osmotic pressure and what is its primary determinant
the pressure of a solution against a semipermeable membrane that prevents water from diffusing across that membrane
-it is a function of the number of osmotically active particles in a solution. not a function of their molecular weights!
osmolarity vs osmolality
osmolarity = osmoles per liter
osmolality = osmoles per kg
reference for plasma osmolarity? and what are the 3 most important contributors
it is 280 - 290 mOsm/L
most important determinatns: sodium, glucose, BUN
Nax2 + Glucose/18 + BUN/2.8
NaCl 0.45%
hypotonic @ 154
D5W
hypotonic @253
NaCl 0.9%
isotonic @ 308
LR
isotonic @ 273
plasmalyte
294
albumin 5%
300
nacl 3%
1026
d5 nacl 0.9% (0.45%)
560, 405
D5 LR
525
How do isotonic IV fluids distribute to the patient?
they expand plasma volume and ECF
remain intravascularly (crystalloids) for30 minutes before moving to the ECF
what is the fda black box for on synthetic colloids
risk of renal injury
coagulopathy risks with colloids
dextran > hetastarch > hextend
dont exceed 20 mL/kg
not a problem with voluven
colloid anaphylactic potential
dextran
albumin leads to what electrolyte abnormality
hypocalcemia
how does hyperkalemia affect the EKG?
5.5 - 6.5 = peaked T wave
6.5 - 7.5 = p wave flattening, PR prolong
7 - 8 = QRS prolonged
> 8.5 = sine wave, VF