Efficacy of erector spinae plane block versus serratus anterior plane block for perioperative analgesia in lateral thoracotomy surgeries: a randomized controlled trial

Background
Lateral thoracotomy is considered one of the most painful types of surgical access. Post lateral thoracotomy pain is attributable to several mechanisms including muscle incisions, rib retraction or resection, intercostal nerves injury, and the presence of an indwelling chest tube. Inadequate pain management can lead to increased postoperative complications, especially in compromised patients. Acute pain may affect pulmonary function and clearance of secretions. Thus, postoperative pain control is crucial in decreasing morbidity and mortality after major thoracic surgery. Numerous analgesic techniques are available for the management of acute postthoracotomy pain, including patient controlled analgesia, regional nerve blockades, and neuraxial blocks. Thoracic epidural analgesia and thoracic paravertebral block are currently the recommended techniques for managing postthoracotomy pain.
Objectives
Our aim was to evaluate the analgesic efficacy of both techniques [erector spinae plane block (ESPB) and serratus anterior plane block (SAPB)] in patients undergoing lateral thoracotomy surgeries.
Patients and methods
Randomized controlled study in which 32 patients American Society of Anesthesiology I–II–III undergoing lateral thoracotomy were enrolled. With age more than or equal to 18 and less than or equal to 60 years. Patients were allocated into two groups: group 1 (SAPB) =16 and group 2 (ESPB) =16. After induction of anesthesia patients received either ultrasound-guided ESPB or SAPB with injection of 20 ml 0.25% bupivacaine. The total amount of morphine consumption in the first 24 h postoperatively. Total amount of intraoperative fentanyl and block related complications were recorded, visual analog scale score, both at rest and during movement, nausea and vomiting scores, and overall patient satisfaction were recorded.
Results
Statistically significant reduction in the mean postoperative morphine consumption was found in group 2 with 4.20±1.55 mg compared to 7.25±2.01 mg in group 1 (<0.001). Statistically significant reduction in the mean intraoperative fentanyl consumption in group 2 with 129.38±40.08 μg compared to 165.63±39.66 μg in group 1 (<0.001). Group 2 showed statistically significant lower scores at visual analog scale at rest and at movement. Among those who required postoperative morphine the mean time to 1st postoperative analgesia in group 1 (=16) was 5.50±2.84 h compared to 9.09±3.62 h group 1 (=16). Two (12.5%) patients of group 1 developed muscle hematoma and two (12.5%) patients complaint from pain at injection site in group 2.