Effectiveness of multimodality neuromonitoring in cardiac surgery

Introduction: Cerebral monitoring during adult cardiac surgery has not received adequate consideration and it is limited to surgery of the aortic arch where brain circulatory damage can be extremely high. Studies conducted to prove the clinical effectiveness of cerebral monitoring have been scarce and restricted to a few centres. The costs to insure against brain injury associated with cardiac surgery are considerable. There are great clinical and economic incentives to improve brain protection during cardiac surgery. Objectives: To evaluate the impact of multimodality neuromonitoring on stroke prevention, length of mechanical ventilation, intensive care and postoperative hospital stays. Methods: Between July 2007 and 2009, we retrospectively compared 166 patients with multimodality brain monitoring during surgery versus a control group of patients without brain monitoring (N = 1555). Statistical analyses were performed using the exact Mann-Whitney U Test and \u3c72. Results: Both groups did not significantly differ in age (p = 0.08) and in risk-stratification score (p = 0.06). Group with brain monitoring had significantly lower incidence of perioperative stroke than those without brain monitoring (p < 0.02). Moreover, patients with brain monitoring had significantly shorter length of mechanical ventilation (p < 0.001) and intensive care unit stay (p < 0.02) than controls. Length of postoperative hospital stay did not show significant difference between groups (p = 0.57). Conclusions: The monitoring with SEP, EEG and Transcranial Doppler provides useful information about brain function and cerebrovascular reserve which in turn might guide the anaesthesiologist during surgery. Although this preliminary experience on multimodality brain monitoring suggests that brain monitoring can reduce neurological complications after cardiac surgery, the continuous monitoring of these neurophysiological variables would intraoperatively provide a better understanding of brain physiology in cardiac surgery patients