Appendicitis is the most common emergency operation in children. The rate of perforation may be related to duration from symptom onset to treatment. A recent adult study suggests that the perforation risk is minimal in the first 36 hours and remains at 5% thereafter. We studied a pediatric population to assess symptom duration as a risk factor for perforation.

We prospectively studied all children older than 3 years who underwent an appendectomy over a 22-month period.

Of 202 patients undergoing appendectomies, 197 had appendicitis. Median age was significantly lower in the perforated group, but temperature and leukocytosis were not. As expected, length of hospital stay was longer in the perforated group (4-13 vs 2-6 days). The incidence of perforation was 10% if symptoms were present for less than 18 hours. This incidence rose in a linear fashion to 44% by 36 hours. Prehospital delays were greater in patients with perforated appendicitis. However, in-hospital delay (from presentation to surgery) was less than 5 hours in the perforated group and 9 hours in the nonperforated group.

Appendiceal perforation in children is more common than in adults and correlates directly with duration of symptoms before surgery. Perforation is more common in younger children. Unlike in adults, the risk of perforation within 24 hours of onset is substantial (7.7%), and it increases in a linear fashion with duration of symptoms. In our experience, however, perforation correlates more with prehospital delay than with in-hospital delay.