Analgesic effect of dexamethasone combined with ropivacaine for thoracic paravertebral nerve block on patients undergoing thoracoscopic lobectomy：A randomized，double-blinded clinical trail
Authors: Gao Xiaopei , Kang Daolin , Zheng Kaiyue , Zhong Hui , Fu Wuchang , Wang Fangjun 
Published: February 2023

Abstract
Background
Far from now, there is still a lack of studies on dexamethasone combined with ropivacaine for ultrasound-guided thoracic paravertebral block (TPVB). Our study aims to observe the analgesic effect of 0.2mg/kg dexamethasone combined with ropivacaine for TPVB on patients undergoing thoracoscopic lobectomy to evaluate postoperative analgesic effect of the compound and prgnosis of patients.
Methods
92 patients who underwent thoracoscopic lobectomy from August 2020 to March 2021 were randomly divided into ropivacaine group (group R) and dexamethasone combined with ropivacaine group (group RD), 46 cases in each group. The group R was performed thoracic paravertebral block with 20ml 0.5% ropivacaine, then the group RD was injected with 20ml of 0.2mg/kg dexamethasone and 0.5% ropivacaine mixture, and general anesthesia induction was performed 30 minutes after the completion of thoracic paravertebral nerve block. The onset time and width of sensory block were observed and recorded. VAS scores were recorded at 1h(T1), 6h(T2), 12h(T3) and 24h(T4). Additional analgesic and sedative drugs for salvage use within 24 hours after operation were recorded. The preoperative fasting glucose level and the postoperative one-day fasting glucose level were recorded. The incidence of side-effects such as skin pruritus, nausea and vomiting were recorded. The extubation time of tracheal intubation and total hospital stay were recorded.
Results
There was no significant difference in the onset time and width of sensory block between the two groups(P > 0.05); The VAS scores at T1, T2, T3 and T4 in group RD were significantly lower than group R(P < 0.05); Compared with group R, the proportion of patients in group RD who received additional morphine rescue analgesia within 24 hours after operation was significantly lower(P < 0.05); while the proportion of patients who received additional midazolam sedation had no significant difference(P > 0.05); The incidence of postoperative nausea and vomiting was similar between the two groups(P > 0.05); There was no significant difference between the preoperative fasting blood glucose and the postoperative one-day fasting blood glucose in group R(P > 0.05); The fasting blood glucose showed an increase on the first day after operation than that before operation in group RD(P < 0.05); Compared with group R, the extubation time in group RD was significantly shorter(P < 0.05); There was no significant difference in surgery time, total propofol and remifentanil assumption during surgery, and total length of hospital stay between group R and group RD as well(P > 0.05).
Conclusion
0.2mg/kg dexamethasone combined with ropivacaine for TPVB can significantly enhance the analgesic effect of ropivacaine in nerve blocks, provide effective and comprehensive postoperative analgesia for patients undergoing thoracoscopic lobectomy, shorten extubation of tracheal tube after operation, and with no increasing incidence of side effects, but exhibit rare influence on the extent of nerve block and total length of hospital stay.
Clinical trial registration:
No. ChiCTR2000033956, registrated at the Chinese Clinical Trial Registry, principal investigator: Xiaopei Gao, date of registration: 18/06/2020.