Effect of chloride liberal fluids on renal and metabolic profiles of patients undergoing off-pump CABGs

Context and Aims: Off-pump coronary artery bypass graft (OPCABG) is a form of CABG surgery. It is performed without the use of cardiopulmonary bypass machine as a surgical treatment for coronary heart disease. Acute kidney injury (AKI) is one of the common postoperative complications of OPCABG. Previous studies suggest important differences related to intravenous fluid (IVF) chloride content and renal function. We hypothesize that perioperative use of chloride restricted IVFs may decrease incidence and severity of postoperative AKI in patients undergoing OPCABG. Methods: Six hundred patients were randomly divided into two groups of 300 each. In Group A (n = 300), chloride liberal IVFs, namely, hydroxyethyl starch (130/0.4) in 0.9% normal saline (Voluven), 0.9% normal saline, and Ringer's lactate were used for perioperative fluid management. In Group B (n = 300), chloride-restricted IVFs, namely, hydroxyethyl starch (130/0.4) in balanced colloid solution (Volulyte) and balanced salt crystalloid solution (PlasmaLyte A), were used for perioperative fluid management. Serum creatinine values were taken preoperatively, postoperatively at 24 h and at 48 h. Postoperative AKI was determined by AKI network (AKIN) criteria. Results: In Group A, 9.2% patients and in Group B 4.6% patients developed Stage-I AKI determined by AKIN criteria which was statistically significant (P < 0.05). Conclusion: Perioperative use of chloride restricted IVF was found to decrease incidence of postoperative AKI. The use of chloride liberal IVF was associated with hyperchloremic metabolic acidosis.