The value of cerebral and somatic near-infrared spectroscopy within an integrated tissue perfusion monitoring strategy in cardiac surgery: A prospective pilot study

IntroductionWe sought to evaluate cerebral and somatic oximetry in an integrated tissue perfusion monitoring strategy.MethodThirty adult patients undergoing full-spectrum cardiac surgery with Minimal Invasive Extracorporeal Circulation (MiECC) were recruited. We simultaneously assessed the adequacy of tissue perfusion with near-infrared spectroscopy (NIRS) for cerebral and tissue oximetry, cerebral autoregulation monitoring (COx), sublingual microcirculation with video microscopy and real-time in-line metabolic monitoring during cardiopulmonary bypass. The primary endpoint of the study was to evaluate the diagnostic accuracy of NIRS cerebral desaturation in predicting a global perfusion-related adverse clinical event.ResultsCerebral oximetry showed the higher positive and negative predicting values (50% and 67%, respectively) in detecting a tissue perfusion-related adverse outcome. Somatic oximetry was related to higher values compared to cerebral (<i>p</i> < .001) and followed a different trend. ROC analysis calculated a cutoff value of 22 for right-sided cerebral desaturation and 32 for cumulative left- and right-sided desaturation as a sensitive predictor of hyperlactemia. Microcirculatory parameters were impaired after induction of anesthesia, while they were preserved during cardiopulmonary bypass.ConclusionsNIRS cerebral oximetry represents a useful tissue perfusion monitoring tool. An AUC cutoff value of 22 for a single hemisphere and 32 bilaterally correlate with hyperlactemia and may serve as alarm for prompt action.