Negative Appendectomy: Clinical and Economic Implications.

Historically, performing a negative appendectomy (NA) was justified to reduce the incidence of perforation. Furthermore, it is also believed that NA is associated with minimal morbidity and cost. The purpose of this study was to evaluate the frequency, clinical characteristics, and economic implications of NA. We reviewed the inpatient admissions on 274,405 patients who underwent nonincidental appendectomy as their primary procedure from the California State Inpatient Databases (2005-2011). Overall, 96.9 per cent had appendicitis (nonperforated = 73.1%, perforated = 23.8% and 3.1%) had NA. NA rates decreased steadily from 4.2 per cent in 2005 to 2.5 per cent in 2011 (P < 0.01). The rates of appendectomy for perforated appendicitis rates also decreased slightly from 25.3 to 23.3 per cent during this time (P = <0.01). Multivariate regression showed that female gender, African American race, and public insurance were all associated with increased NA rates. Compared with patients with appendectomy for nonperforated appendicitis, NA was associated with longer length of stay (NA = 3.2 days vs nonperforated = 1.7 days), higher median cost per admission (NA = $8626 vs nonperforated = $7605), and higher morbidity (4.7 vs 1.9%), all P < 0.01. Contrary to classic justification for NA, we did not find an inverse association of appendectomy for perforated appendicitis and NA at the hospital level. In conclusion, NA is associated with substantial clinical and financial burden, while having no apparent impact on lowering the rate of appendectomy for perforated appendicitis.