Near-Infrared Spectroscopy for Evaluation of Cerebral Autoregulation During Orthotopic Liver Transplantation

Introduction The present study evaluated whether frontal lobe cerebral oxygenation (S c O 2 ), as assessed by near-infrared spectroscopy (NIRS), can detect cerebral autoregulation in patients undergoing orthotopic liver transplantation. Methods We studied changes in frontal lobe S c O 2 assessed in 33 patients, 19 females, who underwent orthotopic liver transplantation (OLT). We evaluated whether S c O 2 would remain stable over a wide range of MAP and whether an eventual drop in S c O 2 could be related to a low MAP. Results Among the 31 of 33 patients for whom a NIRS signal could be detected, S c O 2 varied in parallel with mean arterial pressure (MAP) for 3 patients and, therefore, an autoregulation curve could not be established and yet, there was detected no change in S c O 2 to a lowest MAP ranging from 42 to 66 mmHg for 20 patients, while for 8 patients a decrease in S c O 2 was detected at a MAP of 69 (50–90) mmHg; (median and range). As detected by NIRS, the present study confirms that some patients undergoing liver transplantation do not demonstrate cerebral autoregulation but for the majority of the patients, S c O 2 was stable over a wide range of MAP suggesting that S c O 2 detects cerebral autoregulation. Conclusion We find that NIRS is a ready available non-invasive technology for evaluation of cerebral autoregulation in patients undergoing orthotopic liver transplantation.