Abstract
BACKGROUND: Pectoral nerve blocks I and II (PECS I and II) can be given preoperatively under ultrasound guidance by an anesthesiologist or intraoperatively by a surgeon for postoperative pain control. A comparison of analgesia provided by preoperative versus intraoperative PECS blocks could help surgeons decide which method is most effective while optimizing resources. METHODS: A retrospective review of patients receiving gender-affirming mastectomies at a single institution was conducted from 2018 to 2024. PECS I/II blocks were delivered intraoperatively before August 2023 and preoperatively thereafter. Twenty mL total of 0.25 % bupivacaine with epinephrine was used for PECSI+II blocks. Analgesic effect was measured with opioid consumption (MME) and patient-reported pain score in the PACU. The need for additional opioid medications after discharge was also evaluated. RESULTS: A total of 438 subjects were included, with 84.5 % (370/438) in the intraoperative block group and the remaining 15.5 % (68/438) in the preoperative block group. Opioid consumption did not differ between the two groups (intraoperative: 13.1 ± 6.91 MME vs. preoperative: 12.7 ± 5.32 MME, p = 0.58). Patient-reported pain scores in the PACU also did not differ between the two groups (intraoperative: 3.89 ± 3.26 vs. preoperative: 2.84 ± 2.38, p = 0.54). There was no significant difference in the percentage of patients requiring additional postoperative opioid prescriptions after discharge (preoperative: 4.4 % (3/68), intraoperative: 7.0 % (26/370), p = 0.17). CONCLUSION: Intraoperative PECS I/II blocks should be utilized over preoperative, ultrasound-guided PECS I/II blocks in the setting of gender-affirming mastectomy to provide effective analgesia while optimizing resource utilization and minimizing costs.