Intraoperative continuous venovenous hemofiltration during coronary surgery

Area of Science:

• Cardiology
• Nephrology
• Surgical Innovation

Background:

• Coronary artery bypass grafting (CABG) poses risks to renal function, especially in patients with pre-existing moderate renal dysfunction.
• Continuous venovenous hemofiltration (CVVH) post-surgery can reduce acute renal failure but may prolong intensive care unit stays.
• A novel method for intraoperative hemofiltration integrated with cardiopulmonary bypass was developed.

Purpose of the Study:

• To evaluate the renal protective benefits of intraoperative hemofiltration during CABG in patients with moderate renal dysfunction.
• To compare outcomes between on-pump CABG with intraoperative hemofiltration, on-pump CABG without hemofiltration, and off-pump CABG.

Main Methods:

• A prospective study involving 124 patients with moderate renal dysfunction undergoing CABG between January 2005 and May 2007.
• Patients were divided into three groups: on-pump CABG with hemofiltration (n=40), on-pump CABG without hemofiltration (n=44), and off-pump CABG (n=40).
• Postoperative acute renal failure was defined as dialysis requirement or a ≥50% decline in glomerular filtration rate (GFR). Multivariate analysis adjusted for covariates and propensity scores.

Main Results:

• Multivariate analysis, after adjusting for covariates and propensity scores, indicated that intraoperative hemofiltration and off-pump surgery were protective against postoperative renal dysfunction.
• No significant differences in demographic data or preoperative renal function were observed among the three groups.
• Independent risk factors for postoperative renal dysfunction included age >70 years, left ventricular ejection fraction <35%, and lower preoperative GFR.

Conclusions:

• Intraoperative hemofiltration integrated with cardiopulmonary bypass offers a protective effect on postoperative renal function in patients undergoing CABG with moderate renal dysfunction.
• Off-pump coronary artery bypass surgery also demonstrates a protective effect on renal function in this patient population.
• Age, left ventricular ejection fraction, and baseline GFR are significant independent risk factors for developing postoperative renal dysfunction after CABG.