Efficacy of Erector Spinae Plane (ESP) Block for Non-cardiac Thoracic and Upper Abdominal Surgery: A Single Institute Comparative Retrospective Case Series

Introduction Erector spinae plane (ESP) block was first introduced for the management of thoracic pain but has become increasingly popular for the treatment of abdominal surgical pain. Previous studies have shown the ESP block can be easily adapted to abdominal procedures at the corresponding dermatome level and provide postoperative analgesia. Though the versatility, simplicity, and safety of the ESP block have been demonstrated, there is a gap in the literature regarding its comparison between thoracic and abdominal surgeries. This study aims to evaluate the efficacy of the ESP block in treating acute postoperative pain in patients undergoing thoracic and abdominal surgeries. Methods This retrospective study included 50 patients in the non-cardiac thoracic surgery group (bilateral breast mastectomy with reconstruction) and 50 patients in the abdominal surgery group (robotic or laparoscopic sleeve gastrectomy). Data was obtained via the acute pain service records at a tertiary care center from 2018 to 2022. All patients received bilateral ESP blocks, performed under ultrasound guidance. Various parameters were evaluated including oral morphine equivalents (OMEs) and visual analog scale (VAS) scores during post-anesthesia care unit (PACU), 6, 12, and 24 hours postop. The use of abortive antiemetic medications within 24 hours was also measured to evaluate the incidence of nausea and vomiting. The results were analyzed and compared. No control group is included, as all patients at our institution receive a peripheral nerve block as a part of the institution's enhanced recovery pathway (ERP). Results This retrospective study included 50 patients in the non-cardiac thoracic surgery group (bilateral breast mastectomy with reconstruction) and 50 patients in the abdominal surgery group (robotic or laparoscopic sleeve gastrectomy). Compared to the thoracic group, the abdominal group had a statistically higher VAS score in PACU with mean difference (MD) 1.3 VAS, 95% confidence interval (CI) 0.03-2.56, p-value 0.0443, statistically higher OME consumption in the PACU (difference 13.35 OME, 95% CI 4.97-21.73, p-value 0.0003), and required significantly more antiemetic pharmacotherapy (mean 1.4 antiemetics administered, 95% CI 0.84-2.04, p-value <0.0001). Despite the abdominal group having more OME utilization in the PACU, there was no difference in cumulative OME use in the first 24 hours (95% CI -9.745-24.10, p-value 0.4021). Conclusion In this study, we demonstrated that ESP blocks are an effective regional anesthesia technique to reduce postoperative pain and opioid consumption. The ESP block can serve as a useful and safe alternative to either thoracic epidural or paravertebral block techniques in thoracic and upper abdominal surgeries for perioperative pain management.