Oxygen-linked hydrogen ion binding of canine blood.

Decrease in hemoglobin oxygen saturation without change of true blood base-excess results in an increase in calculated base-excess because of differences in acidity between oxy- and deoxyhemoglobin. We have determined the mean +/- SE canine base-excess correction coefficient to be 0.43 +/- 0.01 mmol base per mmol heme, a value approximately 34% higher than the corresponding value for human hemoglobin.