Vol. 94, Issue 2, 561-566, February 2003
Porcine-specific hemoglobin saturation measurements
Richard
Serianni1,
Jed
Barash1,
Timothy
Bentley2,
Pushpa
Sharma1,
John L.
Fontana1,
Darin
Via1,
Jochen
Duhm3,
Rolf
Bunger4, and
Paul D.
Mongan1
Departments of 1 Anesthesiology and
4 Anatomy, Physiology and Genetics, Uniformed
Services University of the Health Sciences, Bethesda, Maryland 20814;
2 Walter Reed Army Institute of Research,
Washington, District of Columbia 20307; and
3 Department of Physiology, University of Munich,
Munich, Germany 80539
The
determination of O2 consumption by using arteriovenous
O2 content differences is dependent on accurate
oxyhemoglobin saturation measurements. Because swine are a common
experimental species, we describe the validation of CO-oximeter for
porcine-specific oxyhemoglobin saturation. After developing a nonlinear
mathematical model of the porcine oxyhemoglobin saturation curve, we
made 366 porcine oxyhemoglobin saturation determinations with a
calibrated blood-gas analyzer and a porcine-specific CO-oximeter. There
was a high degree of correlation with minimal variability
(r2 = 0.99, SE of the estimate = 5.2%) between the mathematical model and the porcine-specific
CO-oximeter measurements. Bland-Altman comparison showed that the
CO-oximeter measurements were biased slightly lower (
0.4 vol%), and
the limits of agreement (±2 SD) were 0.7 and 1.5 vol%. This is in
contrast to a 10-20 vol% error if human-specific methods were
used. The results show excellent agreement between the nonlinear model
and CO-oximeter for porcine-specific oxyhemoglobin saturation
measurements. In contrast, comparison of the porcine-specific
oxyhemoglobin saturations with saturations obtained by using human
methods highlights the necessity of species-specific measurement methodology.
CO-oximetry; oxyhemoglobin; mathematical modeling
