BACKGROUND: Surgery for breast cancer is common, and intravenous opioids are often used to control postoperative pain. Recently, pectoralis-2 (PECS-2) block has emerged as a promising regional anaesthetic alternative. With nomenclature recently proposed, this block is termed combined PSP/IPP-block (pectoserratus plane block/interpectoral plane block).
OBJECTIVE: We aimed to compare the need for postoperative rescue morphine between the intervention group that received a pre-operative combined PSP/IPP-block and a control group that received peri-operative long-acting opioids for postoperative analgesia.
DESIGN: A randomised controlled study.
SETTING: Operating theatres of two Swedish hospitals. The patients were recruited between May 2017 and October 2020.
PATIENTS: Among the 199 women scheduled to undergo breast cancer surgery (sector resection or radical mastectomy) who were enrolled in the study, 185 were available for follow up.
INTERVENTION: All patients received general anaesthesia. The intervention group received a combined PSP/IPP-block before surgery. The control group received intravenous morphine 30 min before emergence from anaesthesia.
MAIN OUTCOME MEASURE: The primary endpoint was the cumulative need for intravenous rescue morphine to reach a predefined level of pain control (visual analogue scale score <40 mm) during the first 48 h after surgery.
RESULTS: Data from 92 and 93 patients in the intervention and control groups, respectively, were analysed. The amount of rescue morphine administered in the 48 h after surgery was significantly lower in the intervention group than in the control group (median: 2.25 vs 3.0 mg, P = 0.021). The first measured pain score was lower in the intervention group than in the control group (35 vs. 40 mm, P = 0.035). There was no significant difference in the incidence of nausea between the groups (8.7 vs. 12.9%, P = 0.357).
CONCLUSION: The use of a combined PSP/IPP-block block before breast cancer surgery reduces the need for postoperative rescue morphine, even when compared with the use of intra-operative morphine.
TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT03117894.
Wolters Kluwer, 2023. Vol. 40, no 9, p. 636-642