Table 1.

Blood gases, hematocrit, mean arterial pressure, and pump flow

Variable Group	37 °C CPB	31 °C CPB	25 °C CPB	19 °C CPB	15 °C CPB
PH
Alpha-stat	7.42±0.01	7.35±0.01	7.35±0.02	7.41±0.01	7.45±0.01
PH-stat	7.39±0.02	7.31±0.02	7.28±0.02	7.26±0.03*	7.13±0.04*
PaCO2 (mmHg)
Alpha-stat	42.3±1.68	47.2±1.35	45.8±1.49	38.5±1.78	34.0±1.45
PH-stat	46.3±2.15	49.9±2.29	46.6±2.28	63.1±5.20*	84.1±8.21*
PaO2 (mmHg)
Alpha-stat	396±24	411±26	416±25	421±27	428±30
PH-stat	394±22	408±24	411±25	419±26	422±28
Hematocrit (%)
Alpha-stat	24.1±1.00	22.9±0.94	21.1±0.74	19.5±0.64	19.4±0.62
PH-stat	23.9±1.12	22.7±1.10	20.9±0.85	19.4±0.73	19.2±0.78
Mean BP (mmHg)
Alpha-stat	63.6±2.14	58.7±2.11	59.1±1.86	61.2±1.78	64.5±1.82
PH-stat	62.6±1.50	60.0±1.39	59.1±0.68	60.6±1.05	60.2±0.17
Pump flow [ml/(kg·min)]
Alpha-stat	68.9±3.07	68.1±2.97	69.3±2.63	68.1±2.79	67.3±2.68
PH-stat	70.2±3.45	69.5±3.26	70.8±3.47	68.9±3.12	67.8±2.98

Values are mean±SEM

^* P<0.05 vs alpha-stat

CPB=cardiopulmonary bypass; Alpha-stat=alpha-stat group; pH-stat=pH-stat group