INTRODUCTION: Preoperative gabapentinoids are included in many Enhanced Recovery After Surgery (ERAS) pathways, often to reduce opioid consumption. However, a growing body of evidence highlights their hazards, including potential risks of postoperative respiratory depression and somnolence, which are hypothesized to be amplified in the elderly. OBJECTIVE: To determine if preoperative gabapentin negatively affects postoperative somnolence following gynecologic (GYN) surgery in patients greater than or equal to 65 years of age. Additionally, to assess how the administration of preoperative gabapentin may impact postoperative pain and post-anesthesia care unit (PACU) duration in this population. METHODS: This retrospective cohort study utilized a prospective observational dataset for GYN ERAS operations at a quaternary academic medical center. Patients included were aged ≥65 years at index surgery and performed under a GYN ERAS protocol from 1/1/2018 to 1/1/2024. Current protocol permits omitting preoperative gabapentin administration in patients aged ≥65 years without medical contraindications. Therefore, individuals were grouped into two categories for analysis: Compliant Gabapentin Administered (CGA), and Compliant Gabapentin Naïve (CGN). Postoperative somnolence was measured by the Richmond Agitation-Sedation Scale (RASS) during recovery, with the main outcome being time to achieve RASS = 0, “alert and calm.” Given the study’s observational nature, where random assignment of preoperative gabapentin is not possible, a propensity score model with Inverse Probability Treatment Weighting (IPTW, 97%ile trimming) was developed to provide optimal balance between bias reduction and efficiency. The IPTW model was developed to control for age, frailty status, anesthesia type, intraoperative ketamine, intraoperative opioids, and hysterectomy. RESULTS: A total of 764 patients were analyzed, 431 in the CGA group and 333 in the CGN group. The median age was 71 years (67, 75) and median BMI was 27.5 kg/m 2 (24.2, 31.6). Approximately 30% of patients were frail (Clinical Frailty Scale ≥4). Most surgeries (n=446, 58.4%) were performed by urogynecology. Surgical technique varied between vaginal (n=388, 50.8%), robotic/laparoscopic (n=228, 29.8%), and open abdominal (n=148, 19.4%) approaches. In unweighted time-to-event analysis, the CGA group had a longer time to achieve a RASS = 0 (unadjusted HR 1.23 1.06-1.42, p=0.0053). After IPTW adjustment, the weighted HR was 1.16 0.99–1.355, p=0.054, suggesting again a longer time to achieve alertness in the CGA group. Subgroup analysis of those receiving ≥300 mg of preoperative gabapentin showed significantly longer times to achieve RASS=0 (weighted HR 1.30 1.06–1.59, p=0.013), while no significant difference was observed for the 100-mg dose, indicating a dose-dependent effect. Secondary unweighted and weighted outcomes of PACU duration, postoperative day #0 MME administration, max PACU pain score, and last PACU pain score were not significantly different between the CGA and CGN groups. CONCLUSIONS: Higher doses of preoperative gabapentin may contribute to postoperative somnolence in elderly patients. Further, its use in this population does not improve postoperative pain control or reduce opioid consumption.Figure 1Table 1Table 2
Coulter et al. (2026) studied this question.