Table 2:

Intra- and Postoperative Characteristics by Cohort

Characteristics		Pre-Intervention			Intervention
	Overall	STSnonMI	MI-Collaborative	p-value	Overall	STSnonMI	MI-Collaborative	p-value
N	196,954	189,774	7,180		714,800	690,605	24,195
Intraoperative
Cardiopulmonary Bypass Utilization				<0.001				<0.001
Full	80.8	80.4	91.7		84.6	84.3	92.4
None	18.1	18.5	8.0		14.4	14.6	7.4
Cardiopulmonary Bypass Duration, mean (SD), minutes	95.7 (37.8)	95.3 (37.6)	104.1 (42.7)	<0.001	94.8 (37.4)	94.6 (37.3)	100.5 (39.5)	<0.001
Cross Clamp Duration, mean (SD), minutes	68.3 (29.4)	67.9 (29.1)	77.1 (36.1)	<0.001	68.5 (29.3)	68.2 (29.2)	75.5 (32.4)	<0.001
Nadir Hematocrit, mean (SD)	24.7 (4.8)	24.7 (4.8)	25.6 (4.8)	<0.001	25.2 (4.9)	25.2 (4.9)	25.7 (5.0)	<0.001
Blood Products Used	33.9	34.3	24.6	<0.001	28.5	28.8	21.1	<0.001
Red Blood Cells, mean (SD), number	1.81 (1.72)	1.81 (1.72)	1.7 (1.5)	0.78	1.7 (1.7)	1.7 (1.7)	1.5 (1.4)	0.0002
Antibiotic Delivery
Appropriate Selection	97.7	97.7	97.5	0.47	98.6	98.6	99.0	<0.001
Appropriate Timing	98.9	98.9	99.0	0.55	98.9	98.9	98.7	0.0023
Postoperative
Blood Products Used	38.9	39.1	34.2	<0.001	31.0	31.1	27.8	<0.001
Red Blood Cells, mean (SD), number	2.5 (2.7)	2.5 (2.7)	2.6 (2.7)	0.0043	2.4 (2.9)	2.4 (2.9)	2.3 (2.6)	0.46
Prolonged Intubation	10.1	10.1	10.9	0.030	8.5	8.6	8.2	0.071
Major Morbidity/Mortality	13.7	13.7	14.2	0.27	12.2	12.2	11.8	0.030
Operative Mortality	2.4	2.4	1.9	0.0071	2.3	2.3	1.9	<0.001
Postoperative Length of Stay, mean (SD), days	6.9 (5.1)	6.8 (5.2)	7.0 (5.0)	<0.001	6.8 (5.0)	6.8 (5.0)	7.1 (4.7)	<0.001
Antibiotic
Appropriate Discontinuation	97.7	97.7	98.3	0.0003	97.8	97.8	98.4	<0.001

Data are expressed as No. (%) unless otherwise indicated.

P-values are based on Pearson chi-square tests for all categorical row variables.