Impact of early postoperative blood glucose variability on serum endocan level in cardiac surgery patients: a sub study of the ENDOLUNG observational study

BACKGROUND: Early postoperative glycemic variability is associated with worse outcome after cardiac surgery, but the underlying mechanisms remain unknown. This study aimed to describe the relationship between postoperative glycemic variability and endothelial function, as assessed by serum endocan level in cardiac surgery patients. METHODS: We performed a post hoc analysis of patients included in the single-center observational ENDOLUNG study. Adult patients who underwent planned isolated coronary artery bypass graft surgery were eligible. Postoperative glycemic variability was assessed by calculating the coefficient of variability (CV) of blood glucose measured within 24 (CV(24)) and 48 (CV(48)) hours after surgery. Serum endocan level was measured at 24 (Endocan(24)) and 48 (Endocan(48)) hours after surgery. Pearson’s correlation coefficient with 95% confidence interval (95% CI) was calculated between CV(24) and Endocan(24), and between CV(48) and Endocan(48). RESULTS: Data from 177 patients were analyzed. Median CV(24) and CV(48) were 18% (range 7 to 39%) and 20% (range 7 to 35%) respectively. Neither CV(48) nor CV(24) were significantly correlated to Endocan(48) and Endocan(24) respectively (r (95% CI) = 0.150 (0.001 to 0.290; and r (95% CI) = 0.080 (-0.070 to 0.220), respectively). CONCLUSIONS: Early postoperative glycemic variability within 48 h after planned cardiac surgery does not appear to be correlated with postoperative serum endocan level. CLINICAL TRIAL REGISTRATION NUMBER: NCT02542423.