Ropivacaine versus ropivacaine plus dexmedetomidine in serratus anterior plane block patients undergoing post-thoracotomy surgery: a randomized, double-blinded clinical trial.

Background: This study was designed and implemented to investigate the addition of dexmedetomidine to Serratus Anterior Plane Block (SAP) with ropivacaine in reducing pain in patients undergoing post-thoracotomy surgery.

Methods: This study included patients classified as American Society of Anesthesiology (ASA) Physical Status II, with a body mass index (BMI) under 40, who were undergoing thoracotomy at Imam Khomeini Hospital in Ahvaz. The subjects were randomly divided into two groups using a randomized controlled trial design. After surgery, in the recovery room, SAP was performed for patients with ropivacaine (0.4 ml/kg of 0.2% ropivacaine solution) (group R) and ropivacaine plus dexmedetomidine (0.5 μg/kg) (group RD). Pain (with verbal rating scale, VNRS), blood pressure (systolic, diastolic, and mean arterial pressure (MAP)), heart rate (HR), and blood oxygen saturation (O2 sat) were measured and recorded before the intervention, and 1, 6, 12, 24, and 48 h after the intervention.

Results: Finally, 74 patients were included in this study. Both groups exhibited significant pain reduction at one hour, with sustained pain relief observed in the RD group at 6, 12, and 24 h (P < 0.001). The RD group also showed having lower values HR and MAP at 6 and 12 h (P < 0.001). Patients in the RD group received painkillers faster (P = 0.005) and required lower total narcotic usage (P < 0.0001). Two RD group patients experienced transient bradycardia, which resolved without treatment.

Conclusion: The findings of this study show that SAP block with dexmedetomidine is an effective and safe drug along with ropivacaine as a nerve-blocking agent in thoracotomy candidates.