Comparison of Intraoperative Fentanyl Usage and Waste After Transition from 100-μg Vials to 50-μg Preloaded Syringes: A Single-Center Retrospective Study.

Background: The rapidly acting opioid fentanyl commonly used in the perioperative setting, has traditionally been packaged in 100 or 250-μg vials. In September 2021, our institution implemented a change from fentanyl 100-μg vials to 50-μg preloaded syringes in our operating rooms. The objective of this study was aimed at assessing the association of the fentanyl product change on reducing medication waste and the amount of fentanyl administered during surgery.

Methods: This single-center, retrospective study entailed a review of anesthesia records from September 2020 to September 2022 of adult patients who underwent general anesthesia and received fentanyl for surgery at The University of Texas MD Anderson Cancer Center. The data set was divided into a control period (CP) using 100-μg vials and a post transition period (PT) using 50-μg preloaded syringes. The primary outcome measures were the average amounts of fentanyl used and wasted per case. Secondary outcome measures consisted of intraoperative analgesic use as well as postoperative pain scores.

Results: Among the 33,405 cases included in this study, the mean amount of fentanyl used per surgical case was higher in the CP group than in the PT group (133μg vs. 102μg; p<0.001). Additionally, fentanyl waste occurred in a higher percentage of cases in the CP group than in the PT group (13.9% vs. 2.9%; p<0.001). We did not observe a significant difference in post-anesthesia care unit pain scores between the CP and PT groups.

Conclusion: Transitioning to preloaded fentanyl syringes decreased medication waste and overuse of opioids intraoperatively. Simultaneously, the transition did not adversely affect patient analgesia in the post-anesthesia care unit.