AIIMS May 2012 – MCQ 4

Which scientific principle is the basis for thermodilution method used in measurement of cardiac output?
A. Hagen-poisseuille principle
B. Stewart-hamilton principle
C. Bernoulli’s principle
D. Universal gas equation

Correct answer : B. Stewart-hamilton principle

The volume of blood in the heart and lungs can be measured, by the Stewart-Hamilton principle, as the product of cardiac output and the mean transit time from right atrium to the aortic root.
Ref: circ.ahajournals.org/content/33/3/347.abstract

Transpulmonary thermodilution uses the Stewart-Hamilton principle.
Ref: en.wikipedia.org/wiki/Cardiac_output