Outcome of Ultrafiltration in On-pump vs Off-pump Coronary Artery Bypass Grafting in Patients with Renal Impairment

Abstract Objective: Cardiopulmonary bypass circuit (CPB) is a technique used in conventional coronary artery bypass grafting (CABG) that cause many adverse effects including renal dysfunction. Ultrafiltration (UF) removes excess fluid and inflammatory mediators that result from the exposure to the CPB. Therefore, conventional CABG with UF and Off-pump CABG (OPCAB) could provide comparable protective option in reducing adverse effects of CPBMethod: A retrospective study of the chronic kidney disease (CKD) patients who underwent CABG. The renal outcomes were compared between the patients who underwent conventional CABG with UF and the patients who underwent OPCAB. A repeated measure mixed model adjusted by propensity score was used for comparing the renal outcome. Univariable and multivariable logistic regression was used to identify the risk factors for acute renal failure (AKI) and adverse outcomes.Results: From January 2009 and June 2020, there were 220 CKD patients, 109 (49.55%) patients underwent CABG with UF and 111 (50.45%) patients underwent OPCAB. There were statistically significant differences in the change of the average level of creatinine between CABG with UF (increased +0.09 mg/dl) and OPCAB (decreased -0.05 mg/dl) (p=0.043). Also, patients who underwent CABG with UF had significantly increased risk for AKI (OR = 5.38, p=0.038, 95CI 1.09, 26.5)Conclusion: OPCAB tend to provide better renal preservation and protection against post-cardiac surgery AKI than CABG with UF. OPCAB, if technically feasible, would be a preferable choice for patients with renal dysfunction. Study registration number: SUR-2562-06607/Research ID: 6607