Near infrared spectroscopy for frontal lobe oxygenation during non-vascular abdominal surgery

Abstract

Purpose: Cerebral deoxygenation, as determined by near infrared spectroscopy (NIRS), seems to predict postoperative complications following cardiac surgery. We identify the type of non-vascular abdominal surgery associated with cerebral deoxygenation and/or hyperoxygenation, how such deviations affect patient outcome, and whether maintained cerebral oxygenation improves outcome.

Methods: A systematic literature search was performed on PubMed, EMBASE, Web of Science and Clinicaltrials.gov.

Results: A total of 901 patients from 24 publications are described. A decrease in NIRS (>15% relative to baseline) manifested with reverse Trendelenburg's positioning and in 24% (median) of especially elderly patients undergoing open surgery and demonstrated a correlation to hospital stay (LOS). However, if cerebral deoxygenation was reversed promptly, improved postoperative cognitive function (28 versus 26; mini-mental state examination) and reduced LOS (14 versus 23 days) were seen. Also, during liver transplantation (LTx), impaired cerebral autoregulation (25%), cerebral deoxygenation in the anhepatic phase (36%) and cerebral hyperoxygenation with reperfusion of the grafted liver (14%) were identified by NIRS and could lead to adverse neurological outcome, that is seizures, transient hemiparesis and stroke.

Conclusion: NIRS seems important for predicting neurological complications associated with LTx. Also, surgery in reverse Trendelenburg's position and in other types of abdominal surgery about one-fourth of the patients are subjected to episodes of cerebral deoxygenation that seems to predict a poor outcome. Although there are currently only few studies available for patients going through abdominal surgery, the available evidence points to that it is an advantage to maintain the NIRS-determined cerebral oxygenation.

Keywords: cerebral autoregulation; cerebral blood flow; cerebral oximetry; monitoring; surgery; transplantation.