The outcomes of ultrafiltration in on-pump versus off-pump coronary artery bypass grafting in patients with renal impairment

OBJECTIVE: In chronic kidney disease (CKD), using cardiopulmonary bypass (CPB) may contribute to renal dysfunction. Off-pump coronary artery bypass grafting (OPCAB) is one technique that preserved renal function, but the procedure may not be possible in certain situations. The ultrafiltration (UF) can remove excess fluid and inflammatory mediators that result from exposure to the CPB. Coronary artery bypass grafting (CABG) with UF could be an alternative way to preserve renal function. METHOD: A retrospective study of CKD patients who underwent CABG. The renal outcomes were compared between the patients who underwent CABG with UF and OPCAB. A repeated measure 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 a significantly increased risk for AKI (OR 5.38, 95%CI 1.09, 26.5). CONCLUSION: The UF adjunct technique in CABG with CPB tends to provide a lower protective effect for renal function and had a significantly higher incidence of post-cardiac surgery AKI when compared to OPCAB. If technically feasible, OPCAB would be a preferable choice for CKD patients. Study registration number: SUR-2562-06607/Research ID: 6607.