Effect of ultrasound-guided serratus plane block on efficacy of anesthesia and postoperative analgesia in patients undergoing video-assisted thoracoscopy

Objective To investigate the effect of ultrasound-guided serratus plane block (SP) after video-assisted thoracoscopy. Methods Forty patients of being scheduled for selected video-assisted thoracoscopy operation in the Jinshan Sub-Hospital of No.6 Hospital Affiliated to Shanghai Jiao Tong University from August 2016 to October 2017 were prospectively randomized to observation group and control group, 20 patients in each group: SP combined with general anesthesia group (observation group) and general anesthesia group (control group). Patients in observation group received serratus plane injection 20 mL of 0.5% ropivacaine hydrochloride under ultrasound guide 30 min before the surgery. The patients in both groups were received patient-controlled intravenous analgesia after operation. Mean artery pressure (MAP) and heart rate (HR) were recorded at the patients was brought to the operation room rest, 5 min after skin incision and immediately before extubation. visual analgesia scores (VAS) were recorded at 2, 6, 12, 24 and 48 h after operation whenever at rest or during cough. The consumption of propofol and sufentanil during operation were recorded. Meantime, the times of successfully delivered doses (D1) and attempts (D2) within 24 h after operation were added up, calculating D1/D2. The related complications were recorded as well. Results Compared with control group at 5 min after skin incision and immediately before extubation, MAP was significantly lower, HR were significantly decreased in observation group, there were statistical differences (all P values<0.05). The VAS at 2, 6 and 12 h after operation both at rest [(2.0±0.6) point, (2.0±0.8)point, (3.3±1.2)point vs. (4.3±1.5) point, (4.6±2.1)point, (4.5±1.9)point] and coughing [(2.1±0.5) point, (2.1±0.8)point, (3.7±1.4) point vs. (4.6±2.4) point, (4.8±2.2) point, (5.0±1.8)point] in observation group was significantly lower than that in control group, there were statistical differences (all P values<0.05). Propofol consumption [(231±42) mg vs.(412±58) mg] and sufentanil consumption [(35±5.6) μg vs.( 52±6.8) μg] were significantly less in observation group than those in control group, while D1/D2 (0.89±0.12 vs. 0.55±0.11)was higher, there were statistical differences (all P values<0.01). SP was accomplished in observation group without puncture-related complications. Conclusions Ultrasound-guided SP during video-assisted thoracoscopy effectively reduces the pain and the dosage of intraoperative and postoperative analgesics. Key words: Neuromuscular blockade; Serratus anterior; Thoracoscopic surgical procedures; Analgesia, patient-controlled; Ultrasound-guided