Near-infrared spectroscopy for evaluation of cerebral autoregulation during orthotopic liver transplantation

Abstract

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.