Venoarterial PCO2-to-arteriovenous oxygen content difference ratio is a poor surrogate for anaerobic metabolism in hemodilution: an experimental study

Annals of Intensive Care

Table 1 Multiple linear regression model for the ratio of venoarterial PCO₂ to arteriovenous oxygen content difference (P_v–aCO₂/C_a–vO₂)

P_v–aCO₂/C_a–vO₂	Coefficient	Standard error	t ratio	P value	[95% confidence interval]
Ln hemoglobin (g/dL)	−3.60	0.26	−13.62	<0.000001	−4.13 −3.08
Respiratory quotient	2.43	1.03	2.35	<0.03	0.37 4.49
Base excess (mEq/L)	−0.06	0.03	−2.42	<0.02	−0.12 −0.01
Mixed venous O₂ saturation (fraction)	0.03	0.01	3.90	<0.0003	0.01 0.04
Mixed venous PCO₂ (mmHg)	0.15	0.03	4.58	<0.00003	0.08 0.21
Intercept	−0.98	1.72	−0.57	0.57	−4.40 2.44