Journal of Nephrology & Therapeutics

Risk Factors for Acute Kidney Injury Requiring Continuous Renal Replacement Therapy after Off-Pump Coronary Surgery

Abstract

Youhei Tsuchiya ,Isao Tsukamoto ,Hiromichi Suzuki *,Yusuke Watanabe ,Keita Sueyoshi ,Hirokazu Okada

Background: Recently, off-pump coronary artery bypass (OPCABG) grafting without cardiopulmonary bypass has become a less stressful surgical procedure for coronary artery bypass grafting (CABG). Many reports have discussed the risk factors involved associated with on-pump coronary artery bypass grafting and acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT). However, only a few papers have evaluated the risk factors for AKI requiring CRRT after OPCABG. Aim: The purpose of this study was to assess the risk factors for AKI requiring CRRT after OPCAB. Methods: An observational study of 237 consecutive non dialysis patients who underwent isolated CABG using OPCABG was conducted from September 2010 to June 2012. AKI was defined as proposed by the Acute Kidney Injury Network. Variables with P<0.05 in bivariate analysis collected from pre-, intra- and postoperative data were tested in the multivariate and proportional hazards regression analyses for risk factors of AKI requiring CRRT after OPCABG. Results: Among 237 subjects, 33 patients needed CRRT due to AKI. The risk factors that were independently associated with AKI requiring CRRT were: pre-estimated glomerular filtration rate (GFR) (less than 60 ml/min/1.73m2), pre-serum albumin level (less than 3.5 g/dl), pre-hemoglobin level (less than 12g/dL), intra-urine volume (less than 600 mL), use of intra-aortic balloon pump (IABP), and post-PaO2/FiO2 (P/F) (less than 300). Conclusion: In conclusion, it is possible that the risk of developing AKI requiring CRRT after OPCABG depended on the levels of GFR, serum albumin and hemoglobin before surgery, on the levels of urine volume and use of IABP during surgery and the levels of P/F after surgery