The effect of diabetic medications on creatine kinase-myocardial band levels in patients undergoing coronary artery bypass surgery.

Engoren M, Zacharias A, Habib RH, Schwann TA, Riordan CJ, Durham SJ, Shah A.
St Vincent Mercy Medical Center, Toledo, OH, USA.

Ischemic preconditioning has been shown to attenuate the rise in creatine kinase-myocardial band levels that occur with coronary artery bypass surgery (CABG). Recently, concerns have been raised that some sulfonylureas particularly glibenclamide may block ischemic preconditioning.

The purpose of this study was to determine the effect of various diabetic medicines on creatine kinase-myocardial band levels after CABG. In this retrospective study of 799 patients undergoing CABG, patients continued their routine diabetic medicines up to the day of surgery. Intra-operatively and postoperatively, tight glycemic control was maintained with an insulin infusion.

Anesthesia was maintained with isoflurane supplemented by fentanyl. Creatine kinase-myocardial band levels were determined the day after surgery at 5 AM and the mean levels compared between diabetics and non-diabetics and further compared by type of diabetic medicine. After univariable comparisons, linear regression was used to determine the statistically significant predictors of creatine kinase-myocardial band levels.

After correction for other factors, none of the diabetic medicines was a statistically significant predictor of creatine kinase-myocardial band levels. We found that the use of glibenclamide or other diabetic medications had no effect on creatine kinase-myocardial band levels the morning after patients underwent CABG.

Keywords: Ischemic preconditioning; Diabetes mellitus; Sulfonylureas; Coronary artery bypass surgery; Isoflurane; Creatine kinase-myocardial band.