Time to Appendectomy and Risk of Complicated Appendicitis and Adverse Outcomes in Children

Abstract

Importance: Management of appendicitis as an urgent rather than emergency procedure has become an increasingly common practice in children. Controversy remains as to whether this practice is associated with increased risk of complicated appendicitis and adverse events.

Objective: To examine the association between time to appendectomy (TTA) and risk of complicated appendicitis and postoperative complications.

Design, setting, and participants: In this retrospective cohort study using the Pediatric National Surgical Quality Improvement Program appendectomy pilot database, 2429 children younger than 18 years who underwent appendectomy within 24 hours of presentation at 23 children's hospitals from January 1, 2013, through December 31, 2014, were studied.

Exposures: The main exposure was TTA, defined as the time from emergency department presentation to appendectomy. Patients were further categorized into early and late TTA groups based on whether their TTA was shorter or longer than their hospital's median TTA. Exposures were defined in this manner to compare rates of complicated appendicitis within a time frame sensitive to each hospital's existing infrastructure and diagnostic practices.

Main outcomes and measures: The primary outcome was complicated appendicitis documented at operation. The association between treatment delay and complicated appendicitis was examined across all hospitals by using TTA as a continuous variable and at the level of individual hospitals by using TTA as a categorical variable comparing outcomes between late and early TTA groups. Secondary outcomes included length of stay (LOS) and postoperative complications (incisional and organ space infections, percutaneous drainage procedures, unplanned reoperation, and hospital revisits).

Results: Of the 6767 patients who met the inclusion criteria, 2429 were included in the analysis (median age, 10 years; interquartile range, 8-13 years; 1467 [60.4%] male). Median hospital TTA was 7.4 hours (range, 5.0-19.2 hours), and 574 patients (23.6%) were diagnosed with complicated appendicitis (range, 5.2%-51.1% across hospitals). In multivariable analyses, increasing TTA was not associated with risk of complicated appendicitis (odds ratio per 1-hour increase in TTA, 0.99; 95% CI, 0.97-1.02). The odds ratios of complicated appendicitis for late vs early TTA across hospitals ranged from 0.39 to 9.63, and only 1 of the 23 hospitals had a statistically significant increase in their late TTA group (odds ratio, 9.63; 95% CI, 1.08-86.17; P = .03). Increasing TTA was associated with longer LOS (increase in mean LOS for each additional hour of TTA, 0.06 days; 95% CI, 0.03-0.08 days; P < .001) but was not associated with increased risk of any of the other secondary outcomes.

Conclusions and relevance: Delay of appendectomy within 24 hours of presentation was not associated with increased risk of complicated appendicitis or adverse outcomes. These results support the premise that appendectomy can be safely performed as an urgent rather than emergency procedure.

Figure 1.. Assembly of Study Cohort From 23 Children’s Hospitals

Inclusion criteria for consideration included age younger than 18 years; discharged from the hospital between January 1, 2013, and December 31, 2014; and underwent appendectomy for suspected appendicitis. CT indicates computed tomography.

Figure 2.. Variation in the Time to Appendectomy (TTA) and Rates of Complicated Disease at 23 Children’s Hospitals From January 1, 2013, Through December 31, 2014

Boxplots indicate TTA; diamonds, rates of complicated disease; and error bars, minimum and maximum values.

Figure 3.. Relative Odds Ratios (ORs) of Complicated Appendicitis (CA) in Patients Undergoing Late vs Early Appendectomy at 23 Children’s Hospitals From January 1, 2013, Through December 31, 2014

A relative OR of 1 or less suggests a higher risk of CA in the early appendectomy group, whereas an OR greater than 1 suggests a higher risk of CA in the delayed appendectomy group. The relative OR of CA was indeterminate for hospital 11 because of a lack of patients with CA in the early time to appendectomy (TTA) group. Hospitals are ordered based on their relative rankings in the differences in the median TTA of their early and late groups.