Procedure-specific surgical site infection incidence varies widely within certain National Healthcare Safety Network surgery groups.

BACKGROUND

The National Healthcare Safety Network (NHSN) classifies surgical procedures into 40 categories. The objective of this study was to determine surgical site infection (SSI) incidence for clinically defined subgroups within 5 heterogeneous NHSN surgery categories.

METHODS

This is a retrospective cohort study using the longitudinal State Inpatient Database. We identified 5 groups of surgical procedures (amputation; bile duct, liver or pancreas [BILI]; breast; colon; and hernia) using ICD-9-CM procedure codes in community hospitals in California, Florida, and New York from January 2009-September 2011 in persons aged ≥18 years. Each of these 5 categories was classified to more specific surgical procedures within the group. The 90-day SSI rates were calculated using ICD-9-CM diagnosis codes.

RESULTS

There were 62,901 amputation surgeries, 33,358 BILI surgeries, 72,058 breast surgeries, 125,689 colon surgeries, and 85,745 hernia surgeries in 349,298 people. The 90-day SSI rates varied significantly within each of the 5 subgroups. Within the BILI category, bile duct, pancreas, and laparoscopic liver procedures had SSI rates of 7.2%, 17.2%, and 2.2%, respectively (P < .0001 for each) compared with open liver procedures (11.1% SSI).

CONCLUSION

The 90-day SSI rates varied widely within certain NHSN categories. Risk adjustment for specific surgery type is needed to make valid comparisons between hospitals.