EFFECT OF PULSATILE FLOW ON RENAL FUNCTION IN ELDERLY PATIENTS UNDERGOING CORONARY ARTERY BYPASS SURGERY

Abstract

The incidence of acute kidney injury (AKI) after on-pump coronary artery bypass graft (CABG) varies among studies but can be reduced if pulsatile flow is used. The aim of this study is to evaluate pulsatile flow impact on renal function of elderly patients undergoing CABG. Over one year (April 2014 to April 2015) 48 patients above the age of 65 underwent on-pump CABG in our institute. Patients were divided into two groups; pulsatile flow (PFG) and non-pulsatile flow (NPFG) groups. Serum creatinine (S.Cr), creatinine clearance (Cr.Cl) and per-perfusion urine output (UO) were measured. AKI Network criteria were adopted for diagnosis. Mean age was 68 in PFG and 69 in NPFG. Males constituted 83.3% of PFG and 79.2% of NPFG. Although 37.5% of PFG and 41.7% of NPFG were hypertensive, all patients had normal ejection fraction (EF). Both groups had nearly 3 coronary anastomoses, cardiopulmonary bypass (CPB) time of 90 min, cross clamp time of 71 min and mean perfusion pressure of 70 mmHg. Mean S.Cr was the same (0.8 mg/dl) in both groups on 1st postoperative day (POD) but UO was significantly larger (708 ml in PFG vs. 648 ml in NPFG). On 3rd POD, S. Cr didn’t change in PFG but it has significantly increased in NPFG (from 0.76 to 1.0 mg/dl). Moreover, Cr.Cl has significantly improved in PFG (81 vs. 72 ml/min in NPFG). Seven of 48 patients (14.6 %) developed AKI (6; 25% in NPFG). In conclusion; Pulsatile perfusion technique is a simple and safe measure to minimize AKI in the elderly.