Costs of adverse events in intensive care units*

CONTEXT: Iatrogenic injuries are very common in critically ill adults. However, the financial implications of these events are incompletely understood. OBJECTIVE: To determine the costs of adverse events in patients in the medical intensive care unit and in the cardiac intensive care unit. DESIGN, SETTING, AND PATIENTS: We performed a matched case-control analysis on data collected during a prospective 1-yr observation study (July 2002 to June 2003) of medical intensive care unit and cardiac intensive care unit patients at an academic, tertiary care urban hospital. A total of 108 cases were matched with 375 controls in our study. MAIN OUTCOME MEASURES: Costs of care and lengths of stay were determined from hospital billing systems for patients in the medical and cardiac intensive care units. We then determined the incremental costs and lengths of stay for patients with adverse events compared with patients without events while in the intensive care unit. Costs were truncated for patients with a second adverse event on a subsequent day during the intensive care unit stay. RESULTS: For 56 medical intensive care unit patients, the cost of an adverse event was $3,961 (p = .010) and the increase in length of stay was 0.77 days (p = .048). This extrapolated to annual costs of $853,000 for adverse events in the medical intensive care unit. Similarly, for 52 cardiac intensive care unit patients, the cost of an adverse event was $3,857 (p = .023), corresponding to $630,000 in annual costs. On average, patients with events in the cardiac intensive care unit had an increase of 1.08 days in length of stay (p = .003). CONCLUSIONS: Patients who require intensive care are especially at risk for adverse events, and the associated costs with such events are substantial. The costs of adverse events may justify further investment in prevention strategies.