Effects of intranasal dexmedetomidine on emergence agitation in pediatric patients under sevoflurane anesthesia: a meta-analyisis of randomized placebo-controlled trials

Objective To evaluate the effects of intranasal dexmedetomidine on emergence agitation (EA) in pediatric patients under sevoflurane anesthesia. Methods We searched PubMed, EMbase, Web of Science, The Cochrane Library, China National Knowledge Infrastructure, CQVIP and Wan Fang databases for clinical randomized controlled trials (RCTs) concerning the effects of intranasal dexmedetomidine on emergence agitation in pediatric patients under sevoflurane anesthesia from database establishment to October 2019. The primary outcome was the incidence of EA. The secondary outcomes included emergence time, extubation time, the length of postanesthesia care unit (PACU) stay, the percentage of rescue analgesia and adverse reactions. RevMan 5.3 software was used to perform meta analysis, while subgroup analysis was performed according to different dosage and dosing time of dexmedetomidine. Results A total of 12 RCTs were enrolled, including 762 patients where 443 patients were intranasally treated with dexmedetomidine and 319 patients were intranasally given normal saline. According to the results of meta-analysis, no significant differences were found in the length of PACU stay between the two groups (P>0.05). However, compared with the control group, the percentage of rescue analgesia significantly decreased (RR=0.20, 95%CI 0.09-0.44, P＜0.0001), the incidence of severe EA significantly decreased(RR=0.22, 95%CI 0.14-0.35, P＜0.00001), and the incidence of postoperative nausea and vomiting (PONV) significantly decreased (RR=0.44, 95%CI 0.24-0.84, P=0.01). Subgroup analysis suggested that both 1 μg/kg and 2 μg/kg intranasal dexmedetomidine could significanlty decrease the incidence of EA (RR=0.29, 95%CI 0.20-0.42, P＜0.00001 and RR=0.21, 95%CI 0.08-0.57, P=0.002), prolong emergence time (MD=1.48, 95%CI 0.21-2.76, P=0.02 and MD=2.83, 95%CI 0.72-4.94, P=0.009) and extubation time (MD=0.66, 95%CI 0.29-1.03, P=0.00005 and MD=1.61, 95%CI 0.50-2.72, P=0.004). Both preoperative (including prior to anesthesia induction) and intraoperative (including after anesthesia induction) dexmedetomidine could significantly decrease the incidence of EA (RR=0.26, 95%CI 0.19-0.35, P＜0.00001 and RR=0.27, 95%CI 0.20-0.38, P=0.002). Conclusions Intranasal dexmedetomidine can significantly reduce the incidence and severity of EA, decrease the percentage of rescue analgesia and the incidence of PONV, without effects on the length of PACU stay, but may prolong emergence time and extubation time.