Clinical significance of increased lipase levels on admission to the ICU.

Study Objectives: To examine the incidence, risk factors, and sequelae associated with asymptomatic hyperlipasemia in the ICU.

Setting: Medical and surgical ICUs.

Patients: Two hundred forty-five adult critically ill patients admitted to an ICU for > 72 h with a diagnosis other than pancreatitis were studied prospectively.

Measurements: Serum amylase and lipase were measured on ICU admission and every third day until normalized. Clinical parameters including the incidence of ileus, the ability to tolerate enteral feeds, and the results of radiologic studies were also recorded.

Results: Hyperlipasemia was present in 40% of patients (peak, 1,183 +/- 175 U/L; range, 209 to 8,620 U/L) [mean +/- SEM]. Increased multiple-organ dysfunction scores, hypotension, anemia, mechanical ventilation (MV), bacteremia, elevated liver function test results, and elevated creatinine and triglyceride levels were all associated with increased lipase levels. In multivariate analysis, hypotension, anemia, elevated serum bilirubin, and MV were independently associated with higher lipase levels. Although mortality was not different, ICU length of stay and the duration of MV were significantly greater in patients with increased lipase levels (p < 0.05). Fifty patients underwent imaging studies. Pancreatitis was confirmed in 11 patients. The mean peak lipase value was significantly increased in patients with a positive study finding as compared to those with negative findings: 2,231 +/- 715 U/L and 900 +/- 234 U/L, respectively (p < 0.01). Enteral feedings, when initiated, were tolerated in 94% of patients with increased lipase levels and 97% of patients with normal lipase levels.

Conclusions: Elevated serum lipase levels are frequently encountered in critically ill patients. In the majority of these patients, enteral feedings are well tolerated and there are minimal clinical sequelae. Extremely high lipase levels may be associated with radiologic evidence of pancreatitis. Hypoperfusion and inflammatory processes associated with multiple-organ failure appear to be contribute to these increases.