Impact of mean arterial pressure on sublingual microcirculation during cardiopulmonary bypass-Secondary outcome from a randomized clinical trial.

Abstract

In this substudy of a randomized, clinical trial, we explored the sublingual microcirculation during cardiac surgery at 2 different levels of blood pressure. We hypothesized that a higher map during CPB would cause higher MFI. Thirty-six cardiac surgery patients undergoing CABG were included and randomized to either low (40-50mmHg) or high (70-80mmHg) MAP during CPB. SDF video images were recorded from the sublingual mucosa. Recordings were analyzed in a blinded fashion to quantify microcirculatory variables. MAP during CPB in the low target group was 45.0mmHg (SD: 5.3) vs 67.2mmHg (SD: 8.9) in the high target group. We found no significant difference between the 2 groups in MFI during CPB evaluated for AV: 2.91 vs 2.90 (P=.82). For sm AV (<20μm), the corresponding values were 2.87 and 2.85 in the low and high target groups, respectively (P=.82). We found no significant difference in sublingual microcirculatory flow expressed as MFI according to 2 different levels of MAP during CPB.