I. Brief review of principles
a. Determination of Excreted load (mg/min)
Excreted = Filtered load - Reabsortion + Secretion [all are in mass flow units e.g. mg/min]
b. Determination of mass flows
Since C = Mdot/Qdot (where Qdot = dQ/dT)
Then Mdot = C * Qdot
Thus volume flow (Qdot ) and plasma or urine concentrations (C) are needed to determine mass flows (Mdot). (see table layout)
II. A list of some useful HUMAN variables (use 'List all variables' for more)
PNA BICARB PK BUN PPR EXBIC GFR U24 UK UNA UPR
III. Urine N and values
Use Kidney Charts option to only read out values for urine urea N and no other variable.
- you may not use the Kidney charts for Na, K, etc. values. Instead, obtain them directly in a HUMAN experiment via <View variable> or placing relevant variables in <Tables>.
Explore use of a 24 hour urine collection. Values at 25+ hours can be read out in 24 hour urine collection under Charts.... .
IV. Acid handling (optional)
How much acid is (reabsorbed/secreted) each day?
-determine acid excretion per min.. Calculate acid excretion/day. Compare with value obtained via plasma/urine pH difference for the 24 hour period.
recall: pH = - log [H+]
V. Some helpful tips (READ THIS before you begin to work on the table!)
- watch your units carefully - you don't need to convert weights to meq. simply do calculations in G/24 Hrs or as appropriate -units of % are "per 100" e.g. 20 vol.% O2A is 20 ml O2/100 ml blood e.g. 15.4 G% is 15.4 grams per 100 ml of blood note: a dl (= deciliter) which = to 1/10 L (or 100 ml) - milliequivilents may be thought of as electrical' moles e.g. 1 mM Na+ => 1 meq. Na+ 1 mM Ca2+=> 2 meq. Ca2+ EXBIC is really zero. It has a negative value in HUMAN because normal net acid excretion is positive and therefore base excretion is 'negative'. That is, base is conserved. Apologies! Scientific notation in FORTRAN and HUMAN scientific -1.0*10-1 = 0.1 in HUMAN -1.0*E-01 = 0.1
======> Click here to load the data table for this exercise. (formatted in html for printing)