Complication-associated mortality following trauma: a population-based observational study.

Context: Complications are common in the care of trauma patients and contribute to morbidity, mortality, and cost. However, no comprehensive list of surgical complications is widely accepted.

Objectives: To create an empirical list of complications based on the International Classification of Diseases, Ninth Revision (ICD-9) lexicon and estimate the contribution of these complications to mortality.

Design: Retrospective database analysis.

Setting: Office of Statewide Health Planning and Development data set.

Patients: The Office of Statewide Health Planning and Development provided information on 409,393 patients admitted to 1 of 159 California hospitals between 2004 and 2008. We defined a complication to be any ICD-9- coded condition that accrued after hospital admission and significantly increased mortality.

Main Outcome Measures: Odds of mortality for individual complications and number of excess deaths due to individual complications based on attributable risk fractions.

Results: Eighty-two different ICD-9 codes contributed significantly to mortality as complications. Odds ratios ranged from 1.02 (hyperosmolarity) to 46.1 (ventricular fibrillation). There were a total of 175,299 complications (range, 0-14; average 0.4/patient). Twenty-four percent of patients had at least 1 complication. Mortality increased with the number of complications; each additional complication increased mortality by 8%. Absent any complications, there would have been 7292 fewer deaths, a 64% reduction in overall mortality.

Conclusions: Most complication-related mortality is due to 25 individual complications. Eliminating all complications might prevent two-thirds of deaths, but because many complications are not preventable, this figure is the upper bound on possible mortality reduction. Hospitals vary in their proportions of deaths due to complications, and thus, efforts to prevent complications might improve survival at some hospitals.