Effect of erector spinae plane block on intravenous opioid consumption in patients undergoing breast cancer surgery

AIM: Pain management before and after surgery is important for the quality of life in patients undergoing breast surgery. Erector spinae plane block (ESPB) which has been popular in recent years is applied for postoperative analgesia in thoracic and abdominal surgical procedures. We aimed to evaluate the effect of ESPB on postoperative pain and (IV) opioid consumption in patients undergoing breast cancer surgery. MATERIALS AND METHODS: This is a retrospective cohort study. Following the ethics committee approval, we investigated the data of patients who underwent breast cancer surgery between 15.10.2020 and 30.04.2022. Patients that recieved ESPB along with IV PCA were classified as Group 1, and patients who recieved only IV PCA were classified as Group 2. In each group, IV morphine consumptions at 1, 6, 12 and 24th hours postoperatively and pain scores at 1, 6, 12 and 24th hours were recorded. RESULTS: 172 patients were included in the study. Demographic characteristics were comparable between groups. Postoperative morphine consumption at 24th hour was 11,98 ± 6,23 mg in Group 1 and 15,13 ± 5,80 mg in Group 2 (p=<0,001). Morphine consunption at 1, 6, 12 and 24th hours was significantly lower in Group 1 (1st hour p<0.042; 6th, 12th and 24th hours p<0.001). Postoperative 1, 6, 12 and 24th hours NRS scores were respectively 4,68 ± 2,18; 3,79 ± 2,00; 3,51 ± 1,88; 2,65 ± 1,68 in Group 1, and 6,09 ± 1,91; 4,78 ± 1,58; 4,14 ± 1,53; 3,19 ± 1,36 in Group 2. The pain scores were significantly lower in the ESPB Group 1 (1st and 6th hours p<0.001; 12th hour p<0.017; 24th hour p<0.006). CONCLUSION: ESPB reduced postoperative opioid consumption and postoperative pain scores were lower compared to IV PCA in patients undergoing breast cancer surgery. Keywords: Erector spinae plane block, patient-controlled analgesia, breast cancer surgery, opioid, postoperative pain