title: Analgesic effect and adverse events of dexmedetomidine as additive for pediatric caudal anesthesia: a meta-analysis.
abstract: BACKGROUND
  Dexmedetomidine has become a popular additive for regional anesthesia. Aim of this meta-analysis was to assess the effect of this additive on the duration of postoperative analgesia and possible adverse events in pediatrics undergoing orchidopexy or lower abdominal surgery.
  
  
  METHODS
  The literature databases of PubMed, Google Scholar, and Cochrane Library were searched for randomized, controlled trials (RCTs). Odds ratio (OR), weighted mean difference (WMD), and the corresponding 95% confidence intervals (CIs) were calculated using the RevMan software, version 5.2, for data synthesis and statistical analysis, which in accordance with the PRISMA statement.
  
  
  RESULTS
  Six RCTs were selected for this meta-analysis, involving a total of 328 pediatric patients. There was a significant longer duration of caudal analgesia (time to first analgesic requirements) in patients receiving dexmedetomidine with CA compared with CA alone (WMD: -8.21 h; 95% CI: -11.40 to -5.02; P < 0.00001). Side effects in these two groups were comparable (OR: 1.02; 95% CI: 0.51-2.04; P = 0.95). Subgroup analysis indicated there was no significant difference in hemodynamic changes during operation (WMD: 1.78; 95% CI: -3.20 to 6.77; P = 0.48) and the emergence time (time from the end of surgery to opening the eyes on calling) after surgery (WMD: 0.47 min; 95% CI: -5.27 to 6.22; P = 0.87).
  
  
  CONCLUSIONS
  Dexmedetomidine as an additive to local anesthetic provides a significantly longer postoperative analgesia with comparable adverse effects and hemodynamic changes, when compared to local anesthetics alone. There were insufficient data of the effects of different concentrations of dexmedetomidine; further studies are required to explore this issue.
authors.affiliation: Department of Anesthesiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China; Department of Anesthesiology, East Hospital, Tongji University School of Medicine, Shanghai, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Tong
authors.forename: Hao
authors.initials: H
authors.lastname: Ren
authors.forename: Xibing
authors.initials: X
authors.lastname: Ding
authors.forename: Shuqing
authors.initials: S
authors.lastname: Jin
authors.forename: Zhixia
authors.initials: Z
authors.lastname: Chen
authors.forename: Quan
authors.initials: Q
authors.lastname: Li
mesh_terms: D000759:Adjuvants, Anesthesia; D018712:Analgesics, Non-Narcotic / Q000009:adverse effects; D000763:Anesthesia, Caudal / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D020927:Dexmedetomidine / Q000009:adverse effects; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D016032:Randomized Controlled Trials as Topic
chemical_list: D000759:Adjuvants, Anesthesia; D018712:Analgesics, Non-Narcotic; D020927:Dexmedetomidine
keywords: dexmedetomidine; local anesthetics; meta-analysis; pediatrics; randomized controlled trials; regional anesthesia