The Safety and Efficacy of Ultrasound-Guided Serratus Anterior Plane Block (SAPB) Combined with Dexmedetomidine for Patients Undergoing Video-Assisted Thoracic Surgery (VATS): A Randomized Controlled Trial.

Background: Although video-assisted thoracic surgery (VATS) can significantly reduce postoperative pain, the incidence is as high as 30-50%. The purpose of this study was to explore the safety and efficacy of ultrasound-guided serratus anterior plane block (SAPB) combined with dexmedetomidine (Dex) for patients undergoing VATS. Methods: Eighty patients were randomized into two groups (20 mL 0.5% ropivacaine plus 0.5 mu g/kg or 1 mu g/kg Dex). Primary outcome was the visual analog scale of pain while coughing (VASc) score at 24 h after surgery. Secondary outcomes included hemodynamics, sufentanil consumption, number of patients needing rescue analgesia, time to first rescue analgesic, total dose of rescue analgesic, satisfaction scores of patients and surgeons, time of chest tube removal, length of hospital stay, adverse effects, the prevalence of chronic pain and quality of life. Results: Compared with D1 group, visual analog scale of pain at rest (VASr) was significantly lower during the first 24 h after surgery, while VASc was significantly lower during the first 48 h after surgery (P<0.05). Mean arterial pressure was significantly decreased from T2 to T8, and heart rate was significantly decreased from T2 to T7 in the D2 group (P<0.05). Consumption of sevoflurane, remifentanil, DEX and the recovery time were significantly reduced in the D2 group (P <0.05). Consumption of sufentanil 8-72 h after surgery was significantly lower in the D2 group (P<0.05). Additionally, the number of patients who required rescue analgesia, the time to the first dose of rescue analgesia, and the total dose of rescue analgesia was significantly lower in the D2 group (P<0.05). Conclusion: The results of this study show that 1 mu g/kg DEX is a beneficial adjuvant to ropivacaine for single-injection SAPB in VATS patients while stable hemodynamics were maintained.