Liposomal Bupivacaine Reduced Opioid Consumption Following Cesarean Section, Poster Says
A poster from ASHP Midyear 2023 demonstrated the effectiveness of liposomal bupivacaine as it is used for cesarean section procedures, regarded as an area with increasing utilization.
The use of liposomal bupivacaine led to a significant reduction in opioid consumption for patients undergoing cesarean section up to 24 hours following the procedure, but the difference was not significant thereafter, according to a poster presented at this year’s American Society of Health-System Pharmacists Midyear Clinical Meeting & Exposition.1
One notable finding from the study, which aimed to measure whether liposomal bupivacaine, acetaminophen (APAP), or ketorolac led to a significant reduction in opioid utilization in a 72-hour postoperative period following cesarean section, was that utilizing scheduled analgesics led to the greatest reduction in opioid consumption. Further, use of liposomal bupivacaine did not lead to a reduction in opioid consumption in patients who were treated with scheduled APAP and ketorolac.
In the retrospective review, investigators evaluated medical records for 300 patients who underwent cesarean section from June to October 2022. Administration of liposomal bupivacaine, scheduled administration of APAP and/or ketorolac postoperatively, and opioid consumption within 24 hours, 24 to 48 hours, and 48 to 72 hours postoperatively, were tracked. Cumulative opioid consumption up to 48 hours and up to 72 hours post-operatively was also measured.
To measure the primary outcome, which aimed to determine whether liposomal bupivacaine reduced the utilization of opioids in the postoperative period, investigators compared patients who received liposomal bupivacaine with those who did not.
Investigators used 4 sets of comparators to analyze the secondary outcome, which aimed to determine whether the effect of multimodal pain control would further decrease opioid consumption independently of liposomal bupivacaine. These included patients receiving/not receiving scheduled APAP; patients receiving/not receiving scheduled ketorolac; patients receiving scheduled APAP and ketorolac/neither scheduled APAP nor ketorolac; patients receiving scheduled APAP and ketorolac with liposomal bupivacaine/scheduled APAP and ketorolac without liposomal bupivacaine.
Although a significant decrease in opioid consumption was measured in patients using liposomal bupivacaine (4.02 + 13.47 milligram morphine equivalent [MME]) in the first 24 hours of the postoperative phase (P = 0.0214) compared to those not receiving liposomal bupivacaine (11.01 + 16.68 MME), the difference measured at any other timeframe was not significant (P = 0.34).
Patients using scheduled APAP consumed less opioids during all timeframes (0-24 hours P < 0.0001; 24-48 hours P < 0.0001; 48-72 hours P = 0.005). The same opioid consumption effect was observed among patients receiving both scheduled APAP and ketorolac for all time frames (0-24 hours P < 0.0001; 24-48 hours P = 0.0003; 48-72 hours P = 0.0179). Patients who received scheduled ketorolac alone had reduced opioid utilization for 0 to 24 hours (P < 0.0001), 24 to 48 hours (P = 0.0162), 0 to 48 hours (P = 0.0001), and 0 to 72 hours (P = 0.0004).
No statistically significant difference was found between patients who received scheduled APAP and ketorolac with liposomal bupivacaine and patients who received scheduled APAP and ketorolac without liposomal bupivacaine.
Current study results elucidating a reduction in opioid consumption among patients in the postoperative phase address concerns associated with a growing body of research that post-surgical patients are at an increased risk of chronic opioid use.2 Further, the results supplement a lack of literature on the effectiveness of liposomal bupivacaine, typically reserved for orthopedic surgery, as it is used for cesarean section procedures, especially compared to current standard of care therapies.
