QS23. Intra-operative Methadone Decreases Post-operative Opioid Use: A New Eras Protocol in DIEP Flap Patients

Purpose: More than 80% of surgical patients report inadequate pain relief post-operatively, putting these patients at risk for increased morbidity, including surgical complications and chronical post-operative pain. Previous literature has shown that with just one dose of methadone, a long acting μ-opioid, patients undergoing major surgery can achieve better analgesia than with multiple doses of a short acting opioid such as morphine (1). The use of methadone has never been evaluated in the plastic surgery literature. The purpose of this study is to evaluate the effectiveness of our newly instituted Enhanced Recovery After Surgery (ERAS) protocol for patients undergoing deep inferior epigastric perforator (DIEP) flap breast reconstruction, specifically looking at post-operative pain with the institution of a single dose of intra-operative methadone. Methods: This is a prospective study of an ERAS protocol for all patients undergoing a DIEP flap breast reconstruction at a single institution, which centered around the standardization of a single weight based intra-operative dose of methadone. Patients who were operated on after institution of the ERAS protocol were compared to those immediately prior to protocol implementation. Charts were reviewed for patient demographics, intraoperative analgesics, and postoperative medication, both during hospitalization and after discharge. Results: 63 women who underwent DIEP flap reconstruction were identified, with 34 patients in our ERAS cohort compared to 29 in our non-ERAS cohort. The two cohorts had comparable age, weight, BMI, and other medical co-morbidities (p>0.05). The ERAS cohort had significant reduction in opioid usage during the first 12 hours following surgery (12.14 vs 27.28 in morphine milligram equivalents (MME), p=0.006), 24 hours following surgery (39.91 vs 77.40 MME p=0.008) and in total during hospital admission (84.47 vs 146.7 MME, p=0.014). The ERAS cohort also had a significant reduction in their overall daily pain score and heart rate (P<0.05). There was no difference in length of stay (p>0.05) between the two cohorts. On average during the first week after discharge, patients in the ERAS cohort required 13.9 MME of narcotic pain medications per day. 25% of patients did not require any narcotics at home and after 1 week, more then 75% of patients did not require any narcotics at home. Conclusion: This preliminary data after instituting our ERAS protocol with a single dose of intra-operative methadone significantly reduced post-operative opioid analgesic usage. Methadone has the potential to be used for patients undergoing plastic surgery procedures, both inpatient and ambulatory, to decrease post-operative pain, opioid use, and increase overall patient comfort and satisfaction. Further work is ongoing to study the impact of our ERAS protocol on DIEP flap patients’ post-operative course.(1) Komen H, Brunt LM, Deych E, Blood J, Kharasch ED. Intraoperative methadone in same-day ambulatory surgery: a randomized, double-blinded, dose-finding pilot study. Anesth Analg. 2019;128(4):802-810.