Abdominal wall blocks in robotic hysterectomy for endometrial cancer are associated with a modest reduction in the frequency of patients receiving post-operative intravenous opioids.

Objective: To evaluate the association of abdominal wall blocks at the time of robotic hysterectomy performed for endometrial cancer (EC) with in-hospital post-operative opioids. Methods: We performed a retrospective cohort study of patients in the Vizient database who had robotic hysterectomy for EC between January 2019 and December 2022. The exposure was any block coded separate from the surgery, and the primary outcomes were any IV/oral opioid. Fentanyl was excluded due to frequent intra-op use. Length of stay (LOS) and direct cost were compared. The association between block and opioid use was assessed via risk ratio. The quantity of each opioid was expressed in standard resource units (SRU) - a metric used to standardize the consumption of medications across facilities. Results: Three hundred and twenty of the 9062 patients (3.5 %) had a block and 8,742 (96.5 %) did not. Blocks were performed at 66 (20.4 %) hospitals. 184 patients (57.5 %) in the block group received an IV opioid vs 5,890 (67.4 %) of the patients without a block (RR 0.85, 95 % CI 0.77-0.94, p < 0.001). Patients who received blocks were less likely to receive IV (52.5 % vs 64.8 %, RR 0.81, 95 % CI 0.73-0.89, p < 0.001) and oral hydromorphone (6.9 % vs 3.9 %, RR 2.53, 95 % CI 1.68-3.81, p < 0.001) and more likely to receive oral hydrocodone/acetaminophen (11.3 % vs 0.88 %, RR 12.77, 95 % CI 8.73-18.67, p < 0.001). Conclusion: Blocks are infrequently performed and are associated with a modest reduction in the number of patients receiving post-op IV opioids. We found no difference in LOS or cost. Limitations include lack of detail regarding type of block, anesthetic, and phase of care.