Application of ultrasound-guided thoracic paravertebral nerve block combined with PCIA for postoperative analgesia of open partial hepatectomy: a randomized controlled trial

Objective To compare the analgesic efficacy of combined ultrasound-guided thoracic paravertebral block (TPVB) with patient-controlled intravenous analgesia (PCIA) versus simple PCIA after open partial hepatic resection. Methods A total of 120 patients undergoing elective open partial liver resection in our hospital from September 2020 to September 2022 were prospectively recruited, and then randomly divided into the TPVB+PCIA group (Group A) and simple PCIA group (Group B), with 60 patients in each group. Finally, there were 112 patients meeting the criteria and completing statistical analysis. The patients in Group A underwent TPVB at T8~T9 in the left lateral position before anesthesia induction, with injection of 0.33% 30 mL ropivacaine. The patients in Group B had no above treatment. Both groups were given PCIA analgesia pump after surgery. The main outcome measures were analgesia levels at 4, 8, 12, 24 and 48 h after surgery and VAS pain scores at rest and activity. The secondary outcome measures included mean ventricular rate and mean arterial pressure during operation, time required for the first postoperative analgesia relief, number of patients for the first postoperative analgesia relief 48 h after the operation, time for the first postoperative ground exercise, time for postoperative anal exhaust, total number of postoperative hospital days, and incidence of postoperative adverse reactions. Results Compared with the patients of Group B, those of Group A had significantly lower scores of resting VAS and exercise VAS scores at 4, 8, 12 and 24 h after operation (P < 0.001), decreased mean heart rate and mean arterial blood pressure during operation (P < 0.01), less cumulative consumption of tramadol within 48 h (P=0.018), extended time for first postoperative analgesic need (P < 0.001), decreased average number of PCIA effective compressions and number of relief analgesia (P < 0.001), and advanced time of first ground movement and anal exhaust (P < 0.001). But, there were no significant differences in VAS scores at 48 h after surgery, total length of postoperative hospital stay and incidence of postoperative adverse reactions between the 2 groups. Conclusion Combined TPVB+PCIA shows better analgesic effect than simple PCIA for open partial hepatectomy, and it can obtain more stable intraoperative circulation and promote rapid postoperative recovery.