Effect of sodium bicarbonate infusion in off-pump coronary artery bypass grafting in patients with renal dysfunction

Background and Aims: Acute kidney injury (AKI) following cardiac surgery is a major complication resulting in increased morbidity, mortality and economic burden. This study was designed to determine the benefit of sodium bicarbonate (NaHCO3) supplementation in patients with stable chronic kidney disease (CKD) undergoing off-pump coronary artery bypass grafting (OP-CABG). Material and Methods: We prospectively studied 60 non-dialysis CKD patients with glomerular filtration rate (GFR) <= 60 ml/min/1.73 m(2) requiring elective OP-CABG. They were randomly allocatted to one of the two groups. One group received NaHCO3 infusion at 0.5 mmol/kg first hour followed by 0.2 mmol/kg/h till the end of surgery and the other group received 0.9% NaCl. A third group of 30 patients without renal dysfunction undergoing OP-CABG was included. The serum creatinine was estimated prior to surgery, immediately after surgery and on postoperative days 1, 2, 3 and 4. Results: Ten patients (33.3%) in NaCl and 6 (20%) patients each in NaHCO3 and normal groups developed Stage-1 AKI. None of our study patient required renal replacement therapy and no mortality was observed in any of the groups during the perioperative and hospitalization period. Conclusion: Perioperative infusion of NaHCO3 in OP-CABG reduced the incidence of Stage-1 AKI by about 40% when compared to NaCl. The incidence of Stage-I AKI in NaHCO3 group was similar to that in patients with normal renal function undergoing OP-CABG. A larger group of patients may be required to suggest a significance of renal protective benefit of NaHCO3 in patients undergoing OR-CABG