
Physiological aspects on pharmacokinetics 73
As a preliminary application of the principles, Box 4.2 outlines two ways,
used in the clinic, by which the cardiac output can be determined.
4.3.2 The organ transfer function
Consider an organ for which blood supply is through one ingoing and one
outgoing vessel and in which there is no loss of water. Denote the blood flow
in the ingoing and outgoing vessel with Q.LetC
in
be the concentration of
drug in the ingoing vessel and C
out
the concentration in the outgoing one.
Assuming a linear PK system we have a function H(t) such that
C
out
= H ∗ C
in
.
In fact, multiply this with Q and we have to the left the flow of