A LINEAR-APPROXIMATION OF BRODYS EQUATION TO PREDICT OXYGEN-CONSUMPTION IN ADULT HUMANS

Objective. The objective of our study was to derive a linear approxima tion to Brody's equation for oxygen consumption as a simpler alternati ve for the clinician. Methods. The approximation was derived by using calculus to construct a line tangent to Brody's equation at 81 kg. Res ults. The linear approximation was derived to be: VO2 = (2.5w + 67.5) ml/min, where w is the subject's weight in kilograms. The error introd uced by this linear approximation is 10.9% at 30 kg and 1.35% at 120 k g. Conclusions. This linear equation may have utility for approximatin g oxygen consumption when an approximation is required, as in closed c ircuit anesthesia. The utility of this equation is that it is linear a nd produces a result similar to Brody's equation.