Optimal Timing of Postoperative Imaging for Complicated Appendicitis

Approximately one quarter of children with complicated appendicitis develop postoperative abscess, leading to additional procedures and increased length of stay (LOS), but the optimal timing of postoperative imaging to detect abscess is unknown.

The Pediatric Health Information System database was reviewed, and children who underwent laparoscopic appendectomy in 2013-2014 with postoperative LOS ≥5 days were included. Demographics, imaging, drainage procedures, LOS, and 30-day readmission were analyzed. Chi-squared analysis was performed.

A total of 21,985 patients underwent laparoscopic appendectomy and 3332 met inclusion criteria. A total of 1174 (35.2%) patients underwent postoperative imaging, among whom 38.4% underwent ultrasound and 75.0% underwent computed tomography scan. Timing of first imaging varied significantly between hospitals, ranging from 0% to 76% on postoperative day (POD) 5. Initial imaging was performed on POD 5, 6, and 7 in 19.7%, 31.3%, and 36.2%, respectively. Imaging on POD 5 compared with POD 7 was associated with shorter LOS (10.6 ± 5.7 versus 11.8 ± 4.4 days), but also lower rates of intervention (42.4% versus 50.8%), increased repeat imaging (10.8% versus 5.2%), and higher readmission rates (35.9% versus 28.2%) (P < .05).

Timing of postoperative imaging for complicated appendicitis is variable across hospitals. While earlier imaging was associated with a decreased LOS, these children also had lower rates of subsequent intervention coupled with higher rates of repeat imaging and readmission. These findings suggest that delaying imaging until at least POD 6 may maximize the diagnostic yield of imaging while decreasing radiation exposure and readmission. Prospective investigation should be undertaken to guide the development of standardized clinical practice guidelines for the management of perforated appendicitis.