Incidence, risk factors and prognosis of changes in serum creatinine early after aortic abdominal surgery

Abstract

Objective: To determine the incidence, risk factors, and prognostic implications of serum creatinine changes following major vascular surgery.

Design: Observational study.

Settings: University hospital.

Patients: Cohort of 599 consecutive patients undergoing elective abdominal aortic surgery.

Interventions: Review of prospectively collected data from 1993 to 2004.

Measurements and results: The receiver-operator characteristic (ROC) curve analysis was used to detect the best threshold for postoperative elevation in serum creatinine (Delta Creat) in relation to major complications. A cut-off value of +0.5 mg/dl was selected to define renal dysfunction (RD(0.5) group, n=91; no RD(0.5), n=508) that was associated with higher mortality (7.7% in RD(0.5) group vs 1.4% in no RD(0.5) group, P<0.05), rate of admission to the ICU (34% vs 13%, P<0.05), and incidence of cardiovascular (9% vs 4%, P<0.05), respiratory (21% vs 7%, P<0.05), surgical (24% vs 10%, P<0.05), and septic complications (9% vs 3%, P<0.05). After multivariate analysis with logistic regression, renal dysfunction was independently related to low preoperative creatinine clearance [<40 ml/min; odds ratio (OR) 1.5, 95% confidence interval (CI) 1.1-3.9], prolonged renal ischemic time (>40 min; OR, 3.8, 95% CI, 1.9-7.2), blood transfusion (>5 units; OR, 1.9, 95% CI 1.2-6.1), and rhabdomyolysis (OR, 3.6, 95% CI 1.7-7.9).

Conclusions: Postoperative RD(0.5) (Delta Creat >0.5 mg/dl) occurs in 15% of vascular patients and carries a bad prognosis. Preoperative renal insufficiency and factors related to the complexity of surgery are the main predictors of renal dysfunction.