Preoperative Hypoalbuminemia as an Independent Predictor of Postoperative Acute Kidney Dysfunction After Cardiac...

Postoperative acute renal failure associated with mortality after cardiac surgery. Whereas many variables result in postoperative renal failure, current literature lacks commentary on preoperative serum albumin optimization.

We performed a retrospective review of a single adult cardiac surgery center database between 2021 and 2024. Patients were divided into 2 cohorts: preoperative hypoalbuminemia (<3.5 g/dL) and normal albuminemia (3.5-5.4 g/dL). Demographic and clinical characteristics were compared. The primary outcome was kidney injury or kidney failure, defined by the RIFLE (risk, injury, failure, loss of kidney function, end-stage kidney disease) criteria. Multivariable logistic regression evaluated the association of preoperative albumin level and postoperative kidney dysfunction.

There were 1673 patients who underwent cardiac surgery during 4 years, 444 (27%) with hypoalbuminemia and 1229 (63%) with normal albuminemia. The hypoalbuminemia group was younger (63 vs 65 years; P < .01) and less likely to be male (66% vs 71%; P = .04), with lower body mass index (28 kg/m² vs 30 kg/m²; P < .01). Preoperative creatinine concentration (1.0 vs 1.0; P = .85) was comparable between groups. Postoperative kidney dysfunction was significantly greater in the hypoalbuminemia group (12% vs 5%; P < .01). Multivariable logistic regression found hypoalbuminemia to be an independent risk factor for acute kidney dysfunction after cardiac surgery (odds ratio, 1.8 [1.1-3.1]; P < .05).

Hypoalbuminemia is significantly associated with postoperative acute kidney dysfunction in cardiac surgery patients. Preoperative optimization may decrease the risk of renal complications.