The Impact of Mild Renal Dysfunction on Postoperative Mortality in the Surgical Intensive Care Unit

Abstract

The negative impact of mild to moderate renal dysfunction on patient outcome is often under-estimated. Any amount of renal dysfunction is deleterious in the surgical intensive care unit (SICU). We evaluated all surgery patients admitted to our SICU. We identified two groups of patients: no renal failure and acute renal failure. A total of 5152 patients were included in this study. There were 1259 patients in the acute renal failure group. The average number of ventilator days increased by 2.2 for every increase of creatinine by 1.0. Patients who required dialysis stayed an average of 11 days longer than patients who did not have any renal failure. For every increase of creatinine by 1.0, average cost increased by $23,048. Only 7 per cent of the patients with acute renal failure required dialysis (n = 85). The odds ratio for mortality compared with those patients without renal failure was 7.06 (confidence interval, 3.91-12.76) regardless of the definition of renal failure. This study demonstrates that even mild to moderate renal failure increases mortality. Moreover, we demonstrated that even a mild decline in renal function increases length of stay, ventilator days, and cost in patients in the SICU. Aggressive vigilance in the prevention of any loss of renal function is warranted in the SICU.