Preliminary Experience in Combined Somatic and Cerebral Oximetry Monitoring in Liver Transplantation.

OBJECTIVE: The use of cerebral near-infrared spectroscopy (NIRS) has become widespread in cardiac surgery after research demonstrated an association between perioperative cerebral desaturations and postoperative complications. Somatic NIRS desaturation also is associated with an increased risk of postoperative complications and mortality. The objective of this study was to explore the trends of both somatic and cerebral NIRS during liver transplantation.

DESIGN: A prospective, single-site, observational case series.

SETTING: Tertiary care center.

PARTICIPANTS: The study comprised 10 patients undergoing liver transplantation.

INTERVENTIONS: NIRS sensors were placed on the forehead (cerebral regional oxygen saturation [rSO2 ]) and on the right arm and right leg (somatic rSO2 ) to measure tissue perfusion. Desaturation was defined as a 20% decrease of baseline values for 15 seconds.

MEASUREMENTS AND MAIN RESULTS: In all patients, parallel changes in both cerebral and somatic rSO2 values were observed during phlebotomy, bleeding, transfusion, portal vein clamping, and the use of vasoactive agents. Induction of anesthesia increased cerebral rSO2 more than it did somatic values. However, ascites removal, abdominal manipulation, and clamping of the inferior vena cava (IVC) were associated with nonparallel changes in cerebral and somatic rSO2 . Ascites removal was associated with increased somatic leg rSO2 , and IVC clamping and abdominal hypertension were associated with a significant reduction in somatic leg rSO2 . Somatic leg desaturation instead of arm or cerebral desaturation was associated with more postoperative complications.

CONCLUSIONS: The use of combined NIRS monitoring allows for the identification of the source of somatic or cerebral desaturation. Compromised venous flow from the IVC from clamping or abdominal compartment syndrome typically is associated with the appearance of more pronounced leg than arm desaturation.