Utility of near infrared light to determine tissue oxygenation during hepato-biliary surgery

Near-infrared spectrophotometry assesses cerebral oxygen saturation (ScO2) based on the absorption spectra of oxygenated and deoxygenated hemoglobin, and the translucency of biological tissue, in the near-infrared band. There is increasing evidence that optimising cerebral oxygenation, guided by ScO2, is associated with improved outcomes in a variety of high risk surgical settings. However, in patients with liver disease, bilirubin can potentially render cerebral oximetry inaccurate. As a result, measurement of cerebral oxygen saturation is rarely undertaken in patients undergoing hepatobiliary surgery. We prospectively measured baseline and intraoperative cerebral oxygen saturation in patients undergoing major pancreatic surgery. Indices including bilirubin, sodium, platelets and maximum amplitude on thromboelastography were associated with low baseline ScO2. However, those patients with low ScO2 (≤51%) maintained a similar trend in cerebral oximetry values both at induction and intraoperatively to those with a normal ScO2. We conclude that the pattern of cerebral oximetry is similar in patients undergoing major pancreatic surgery regardless of their underlying liver dysfunction. Therefore, cerebral oximetry may have a role in monitoring neurological function in this high risk group of patients.