RENAL PROTECTION BY DILTIAZEM IN PATIENTS UNDERGOING CORONARY ARTERY BYPASS GRAFT SURGERY

Background: Diltiazem dilates renal vessels, increasing renal blood flow and glomerular filtration rate (GFR). It has direct cytoprotective effects by inhibiting increased intracellular calcium load related to an ischemic renal insult. We evaluated the renal protective effects of diltiazem infusion in patients undergoing on pump coronary artery bypass graft (CABG) surgery. Methods: Eighty patients, with normal preoperative renal functions, undergoing elective first-time CABG surgery using cardiopulmonary bypass (CPB) were included in a randomized prospective study. The patients were randomly allocated in two groups; control group (n=40) and diltiazem (DTZ) group (n=40), in which diltiazem was continuously infused at a dose of 2 pg/kg/min started after induction of anesthesia and discontinued at the end of surgery. Results: Urine output in the DTZ group was significantly higher than the control group; both intraoperatively and during the rest of the day of the surgery. Preoperative creatinine clearance, serum creatinine and blood urea were comparable in both groups. However, the postoperative values were significantly different. Postoperative creatinine clearance was significantly higher in the DTZ group than the control group (P 0.001), while serum creatinine and blood urea were significantly higher in the control group than in the DTZ group (P 0.001). Conclusion: Intraoperative diltiazem infusion is useful adjuvant to maintain renal functions perioperatively and prevent further glomerular damage in patients undergoing on pump CABG.