Jugular Venous Oxygen and Lactate Parameters for Predicting Early Cognitive Dysfunction after Off-Pump Coronary Artery Bypass Grafting: A Prospective Observational Study.

Background and objectives: The quality of life may be negatively impacted by postoperative cognitive dysfunction (POCD) following off-pump coronary artery bypass grafting (OPCAB). It is still unclear how useful the jugular venous lactate and oxygen parameters are in predicting POCD following OPCAB.

Methods: This prospective observational study was conducted over a period of 15 months and included 54 individuals. It sought to determine the sensitivity and specificity of jugular venous lactate and oxygen parameters for early POCD prediction in patients undergoing OPCAB. Neuropsychological tests were conducted to assess baseline cognitive function. Under ultrasound guidance, the jugular bulb was cannulated. The jugular venous lactate and oxygen parameters were measured at the time of surgery, following each graft, and 6 and 24 h later. Confusion assessment method-intensive care unit score was assessed on the third postoperative day for postoperative delirium (POD). POCD was defined as a composite Z score ≥1.96 or two Z scores in individual tests at 1 week. The jugular venous lactate and oxygen parameters of the Decline (D) group were compared to those of the Normal (N) group. Receiver operating characteristic curves were used to assess the diagnostic efficacy of derived variables.

Results: The incidence of POD and POCD was 18.5% and 11.1%, respectively. At T3, all derived variables showed a significant increase, although the arterio-jugular venous lactate difference (AJDL) and modified lactate oxygen index (mLOI) were substantially greater at T3 in group D compared to group N. When predicting POCD, mLOI demonstrated the highest sensitivity at 72.22%, while AJDL showed the highest specificity at 90.7%.

Conclusions: For prediction of early POCD in patients undergoing elective OPCAB, mLOI had highest sensitivity, while AJDL had high specificity.