Predictive variables for postoperative opioid requirements following hysterectomy

Abstract

Objectives To identify predictive factors for opioid consumption following hysterectomy by determining the relationship between perioperative opioid requirements, preoperative pelvic pain scores and patient variables. Methods A prospective cohort study of women undergoing hysterectomy at a tertiary care academic hospital was conducted. Preoperatively, all patients completed the Pain Sensitivity Questionnaire (PSQ), Pain Catastrophizing Scale and the Numeric Rating Scale (NRS). Cumulative opioid consumption (COC), calculated in oral morphine equivalents (OME), was the sum of opioid consumption at three time periods; (i) intraoperatively, (ii) recovery room, and (iii) first 24 hours postoperatively. Results 191 women underwent hysterectomy, 68 vaginal (36%), 91 laparoscopic-assisted (48%), and 32 open (17%). The mean age and body mass index were 50 (27–77) and 27 (17-64) kg/m2, respectively. Most hysterectomies (138, 73%) were performed in premenopausal women. The majority were for benign indications (166, 87%), and 40 (21%) were pain-related. Median COC for all hysterectomies was 75 mg OME, and median 24h postoperative COC was 16 mg OME. In multivariate analysis, preoperative NRS scores, PSQ minor scores, preoperative use of pain medication and an open approach were found to be significant predictors of increased COC. Conclusions Predictors of cumulative postoperative opioid requirements for hysterectomy include preoperative NRS scores, PSQ minor scores, number of preoperative pain medications, and surgical approach. This information can be used to create a predictive calculator to individualize perioperative interventions, optimize postoperative pain management, and tailor opioid use.