Table 4.

Multivariable Predictors of Post-CPB Antithrombin (AT) Activity

Predictor	Univariate estimate	Predictors of post-CPB AT activity (U/mL) (n = 1205a; r2 = 0.504)
		Multivariate estimate estimate	multivariate estimate estimate Standard error of	P
Age (1 yr increment)	−0.0030	−0.0006	0.0002	0.0110
Gender (female)	0.0356	0.0023	0.0039	0.5581
Race (Caucasian)	−0.0068	−0.0022	0.0033	0.4979
Height (1 cm increment)	0.0023	0.0010	0.0003	0.0045
Weight (1 kg increment)	0.0015	0.0006	0.0001	<0.0001
Institution	−0.0492	−0.0236	0.0038	<0.0001
Preoperative AT activity (U/mL)	0.4870	0.4698	0.0174	<0.0001
CPB duration (10 min increment)	−0.006	−0.004	0.001	<0.0001
Lowest venous temperature during CPB (1°C increment)	0.0030	0.0044	0.0011	<0.0001
Intraoperative packed red blood cell transfusion (1 unit increment)	−0.0095	−0.0085	0.0021	<0.0001
Intraoperative cryoprecipitate transfusion (1 pooled unit increment)	0.0497	0.0491	0.0150	0.0011
Post-CPB hemoglobin (1 g/dL increment)	0.0177	0.0184	0.0018	<0.0001

^a198 subjects were missing one or more of the model’s predictor variables and are not included in this analysis.

CPB = cardiopulmonary bypass.