Hospital teaching status and outcomes of complex surgical procedures in the United States

Hypothesis: Complex operations performed in teaching hospitals have similar outcomes as those performed in nonteaching hospitals. Design: Observational cohort study with clinical patient data obtained from the Nationwide Inpatient Sample. The Nationwide Inpatient Sample data were linked to the American Hospital Association hospital survey data for 1997 to determine hospital characteristics. Hospitals were considered high volume if they performed more than the median (50th percentile) number of procedures per year. Setting: Nationally representative sample of hospitals during 1996 and 1997. Patients: Individuals undergoing esophageal resection (n=1247), hepatic resection (n= 2073), or pancreatic resection (n=3337) in Nationwide Inpatient Sample hospitals during 1996 and 1997 were included. Main Outcomes Measures: Unadjusted and adjusted in-hospital mortality and prolonged length of stay (>75th percentile). Results: None of the procedures had higher operative mortality rates at teaching hospitals. In unadjusted analyses, pancreatic resection (4.0% vs; 8.8%; P<.001), hepatic resection (5.3% vs 8.0%; P=.03), and esophageal resection (7.7% vs; 10.2%; P=.10) had lower operative mortality rates at teaching compared with nonteaching hospitals. However, after adjusting for hospital volume in the multivariate analysis, hospital teaching status was no longer a predictor of operative mortality. Conclusions: Teaching hospitals have lower operative mortality rates for complex surgical procedures. However, the lower mortality rates at teaching hospitals can be explained by higher procedural volume.