Association of Mean Arterial Pressure during Cardiopulmonary Pump and Incidence of Delirium after Coronary Artery Bypass Graft Surgery

Background: Despite improved outcomes after cardiac operations, delirium is a common neurologic complication after cardiac surgery. In this study, we aimed to investigate the association of postoperative delirium and mean arterial pressure (MAP) during cardiopulmonary pump in patients after coronary artery bypass graft (CABG). Methods: 100 inpatients submitted to coronary artery bypass graft were evaluated prior to and after surgery. In order to investigate the association between mean arterial pressure and incidence of delirium, data were collected at pre intra, and postoperative periods. The patients were examined for delirium using Mini-Mental State Examination (MMSE). Findings: Preoperative delirium was detected in 34 patients (34%) and 74 patients (74%) had postoperative delirium. There was a significant positive correlation between total score of MMSE and mean arterial pressure during cardiopulmonary pump (r = +0.22, P = 0.02). Furthermore, there was a significant correlation between total score of MMSE and O2 saturation (r = +0.22, P = 0.03). Conclusion: Present study suggests associations between incidence of postoperative delirium and mean arterial pressure and O2 saturation during cardiopulmonary pump. Maintaining mean arterial pressure and O2 saturation of blood at physiologic levels during cardiopulmonary pump may be associated with less early postoperative delirium and cognitive dysfunction.