Preoperative Opioids Associated With Increased Postoperative Opioid Use in Pediatric Appendicitis

Background: In light of current opioid-minimization efforts, we aimed to identify factors that predict postoperative opioid requirement in pediatric appendicitis patients. Methods: A single-center retrospective cohort study was conducted of children (<18 y) who underwent laparoscopic appendectomy for acute appendicitis between January 1, 2018 and April 30, 2019. Patients who underwent open or interval appendectomies were excluded. The primary outcome was morphine milliequivalents (MMEs) per kilogram administered between 2 and 24 h after surgery. Multivariable analyses were performed to evaluate predictors of postoperative opioid use. Clinically sound covariates were chosen a priori: age, weight, simple versus complicated appendicitis, preoperative opioid administration, and receipt of regional or local anesthesia. Results: Of 546 patients, 153 (28%) received postoperative opioids. Patients who received postoperative opioids had a longer median preadmission symptom duration (48 versus 24 h, P < 0.001) and were more likely to have complicated appendicitis (55% versus 21%, P < 0.001). Patients who received postoperative opioids were more likely to have received preoperative opioids (54% versus 31%, P < 0.001). Regional and local anesthesia use was similar between groups. Nearly all patients (99%) received intraoperative opioids. Each preoperative MME per kilogram that a patient received was associated with receipt of 0.29 additional MMEs per kilogram postoperatively (95% confidence interval, 0.19-0.40). Conclusions: Preoperative opioid administration was independently associated with increased postoperative opioid use in pediatric appendicitis. These findings suggest that preoperative opioids may potentiate increased postoperative pain. Limiting preoperative opioid exposure, through strategies such as multimodal analgesia, may be an important facet of efforts to reduce postoperative opioid use.