Evaluating the effectiveness of a discharge protocol for children with advanced appendicitis

BackgroundIn 2006, an evidence-based protocol for the management of children with appendicitis was established at our institution. Discharge criteria for patients with advanced appendicitis were based on a combination of clinical parameters and laboratory values. The purpose of this study is to evaluate the utility of laboratory values in guiding patient management with a discharge protocol for advanced appendicitis.Materials and methodsWe reviewed charts of patients with advanced appendicitis as defined by the surgeon intraoperatively from 2008–2009. We evaluated the sensitivity and specificity of the laboratory values at discharge for predicting postoperative intra-abdominal abscess (IAA) formation using a receiver operator curve. A logistic regression analysis was performed to identify predictors of IAA formation.ResultsWe identified 450 patients (mean age 8.9 ± 3.9 y). The postoperative IAA rate was 25%. The sensitivity and specificity for developing an abscess with a white blood cell count >12,000/UL were 52% and 82%, respectively (AUC 0.72, 95% CI 0.67–0.78, P < 0.001). The sensitivity and specificity for bands >3% were 47% and 70% (AUC 0.60, 95% CI 0.53–0.67, P = 0.002), respectively. On logistic regression analysis, an elevated white blood cell count was independently associated with an increased likelihood of a postoperative IAA (OR 1.27, 95% CI 1.19–1.35, P < 0.001).ConclusionsThe absence of leukocytosis is useful for identifying children with a decreased risk of postappendectomy IAA formation who otherwise meet clinical discharge parameters. A band count is not as predictive of risk. The use of laboratory evaluation as a component of discharge criteria in advanced appendicitis can stratify a subset of patients who are at increased IAA risk and may benefit from continued antibiotic therapy.