Elevated blood urea nitrogen is an independent risk factor of prolonged intensive care unit stay due to acute necrotizing pancreatitis

Abstract

Purpose: The aim of this study was to analyze the predictive value of blood urea nitrogen (BUN) and other variables in acute necrotizing pancreatitis on hospital stay, intensive care unit (ICU) stay, and death.

Materials and methods: We retrospectively analyzed 118 consecutive case records of patients admitted with acute pancreatitis. Forty-four patients had a severe acute necrotizing pancreatitis and only those were analyzed. We compared variables on admission and in the course of the disease in association to hospital stay, ICU stay, and death.

Results: Patients with elevated BUN on admission had a significantly prolonged ICU stay (> or =14 days: 32 +/- 25 mg/dL vs <14 days: 15 +/- 8 mg/dL; univariate P = .007; multivariate P = .0390; odds ratio, 1.042; 95% confidence interval, 1.002-1.084). Positive and negative predictive values (PPV, NPV) were 89% and 62% with a cutoff at 33 mg/dL. The ICU stay was also significantly prolonged when BUN was elevated in the course of the disease (> or =14 days: 60 +/- 33 mg/dL vs <14 days: 20 +/- 8 mg/dL; P < .0001; PPV 89% and NPV 77%). Mortality in patients with elevated BUN on admission was significantly increased (nonsurvivors: 39 +/- 30 vs survivors: 17 +/- 11 mg/dL; P = .028; PPV 67%, NPV 82%). Later in the course of the disease, elevated BUN was also associated with increased mortality (nonsurvivors: 69 +/- 38 mg/dL vs survivors: 27 +/- 16 mg/dL; P = .003; PPV 56% and NPV 92%).

Conclusion: Although not as reliable as complex clinical scoring systems, BUN as a single marker is a useful routine, easy to perform, and a cheap marker to predict ICU stay and probable survival in acute necrotizing pancreatitis.