Background: Acute renal failure (ARF) requiring renal replacement therapy (RRT) after cardiac surgery remains a cause of major morbidity and mortality (1). Our objective is to assess the incidence and outcome of ARF after cardiac surgery with cardiopulmonary bypass (CPB) in 2004 compared to 2002.
Methods: We compared retrospectively demographic and perioperative data in consecutive adult patients undergoing cardiac surgery with CPB in 2002 (544 patients) and 2004 (276 patients). ARF was defined as a rise in serum creatinine above 120 μmol/l or twofold rise of baseline value. RRT was indicated on clinical and biological grounds. Data are expressed as mean ± SD. Continuous variables were analyzed with unpaired t-test. Categorical variable were compared by Fisher's exact tests and a P-value of <0.05 was considered significant.
Results: There is no difference regarding demographic, perioperative factors and type of surgery in the two groups. In 2004, 7.6% of patients developed ARF after cardiac surgery with CPB compared to 11.9% in 2002 (p = 0.0027). 3.7% of all patients required RRT in 2002 vs. 1.4% in 2004 (p = 0.029). In-hospital mortality in ARF patients decreased between the two periods of time: 20% in 2002 vs. 4.8% in 2004 (p = 0.015). There is no statistical difference regarding in-hospital mortality in ARF patients requiring RRT: 52.4% in 2002 vs. 25% in 2004 (p = 0.23). Higher percentage of patients received aprotinin (38% vs. 21%, p < 0.001), metilprednisolon (42% vs. 16%, p < 0.001) and introperative hemofiltration (15.3% vs. 8%, p = 0.002) in 2004 compared to 2002.
Conclusions: The incidence of ARF after cardiac surgery decreased significantly in 2004 compared to 2002. The outcome of the patients with ARF improved. Larger used of anti-inflammatory strategy (aprotinin, metilprednisolon and intraoperative hemofiltration) may be involved in decreasing the incidence of ARF in cardiac surgery.