During Hypothermic Cardiopulmonary Bypass-Correlation with Oxyhemoglobin Saturation

In 8 adult patients undergoing cardiopulmonary bypass, the perfusion flow was altered from 2.4 to 1.8 and 1.2 L/min/m during hypothermia (26.5 ± 2.3°C). Following rewarming of the patients to 37°C, the perfusion flow was also altered from 2.4 to 1.8 and 1.2 L/min/m • The resulting mixed venous oxyhemoglobin saturation (Sv0 2 ) was measured in vivo by in-line oximetry at the actual body temperature, and was correlated with the corresponding temperature-corrected and uncorrected mixed venous oxygen tension (Pv0 2 ) as measured in the lab at 37°C. Venous blood at the entrance of the oxygenator was used for continuous in-line oximetry, blood gas sampling, and for measuring body temperature .