Ultrasound Guided Serratus Anterior Plane Block Versus Costotransverse Block on Postoperative Analgesia and Safety Following Modified Radical Mastectomy Surgeries

Background: Early ambulation after a modified radical mastectomy (MRM) depends on effective pain management. Persistent neuropathic pain in the thorax is a hallmark of post-mastectomy pain syndrome (PMPS). Methods: Ninety female patients who underwent mastectomy with reconstruction participated in this trial. Group A received 30 mL of bupivacaine 0.25% preoperatively for the serratus anterior plane block (SAPB). Group B, which underwent the costotransverse block (CTB), received 30 mL of bupivacaine 0.25% preoperatively at the level of the fourth transverse process. Group C was given a patient-controlled analgesia (PCA) pump that delivered 20 mg of nalbuphine in 100 mL of 0.9% normal saline at a baseline infusion rate of 5 mL/hr. The main outcomes were the Visual Analog Scale (VAS) scores at rest and during arm abduction at 0, 6, 12, and 24 hours, as well as the incidence of PMPS at 6 months postoperatively. Results: At 0 and 6 hours, all groups showed no statistically significant differences. At 12 and 24 hours, CTB performed better than SAPB. The PCA group had the lowest pain control (P < 0.001). The PMPS after 6 months was lowest in the CTB group (13.3%) and highest in the PCA group (46.7%). Conclusions: Following MRM operations, USG single-shot CTB at the T4 level was equally effective as SAPB for managing acute and chronic pain.