title: Dexmedetomidine as adjunct to ilioinguinal/iliohypogastric nerve blocks for pediatric inguinal hernia repair: an exploratory randomized controlled trial.
abstract: BACKGROUND
  Adult meta-analysis has identified dexmedetomidine as a potentially useful adjunct to prolong the duration of peripheral nerve blocks. However, no data exist regarding the adjuvant use of dexmedetomidine in the setting of pediatric peripheral nerve blocks.
  
  
  METHODS
  Using a prospective, randomized, double-blind design, children (1½-8 years, ASA 1-2) scheduled for outpatient inguinal hernia repair were randomized to receive either an ultrasound-guided ilioinguinal/iliohypogastric nerve block (IINB) with plain ropivacaine 0.197% (Group LA; n = 21) or ropivacaine 0.197% with adjunct dexmedetomidine 0.3 μg·kg(-1) (Group LAD; n = 22). The primary endpoint of the study was time to first postoperative administration of supplemental analgesia (FPASA) triggered by a pain score ≥4 (CHIPPS or NRS scale). Intention-to-treat (ITT) analysis was decided as the primary statistical analysis of the data.
  
  
  RESULTS
  The median time to FPASA was prolonged by 88% following the use of adjunct dexmedetomidine (4.0 and 7.6 h in group LA and LAD, respectively) (P = 0.0717). Patients in Group LA displayed a significantly higher number of patients with a CHIPPS score ≥4 in the PACU (7 vs 0; P = 0.0029) as well as a higher incidence of PAED (4 vs 0; P = 0.0485) when compared to patients in Group LAD. No adverse events were recorded in any of the study groups.
  
  
  CONCLUSIONS
  The use of dexmedetomidine as an adjunct to an IINB resulted in reduced incidences of CHIPPS pain scores ≥4 and PAED scores of ≥11 during early recovery following pediatric inguinal hernia repair. In addition, the use of adjunct dexmedetomidine was associated with a prolongation of the period to first supplemental analgesia demand. The results of the present exploratory study must be viewed as preliminary and need further validation by future larger sized studies and/or meta-analysis.
authors.affiliation: Department of Paediatric Anaesthesia & Intensive Care, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Märit
authors.initials: M
authors.lastname: Lundblad
authors.affiliation: Department of Anaesthesia and Intensive Care Medicine, Medical University of Vienna, Vienna, Austria.
authors.forename: Daniela
authors.initials: D
authors.lastname: Marhofer
authors.affiliation: Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Staffan
authors.initials: S
authors.lastname: Eksborg
authors.affiliation: Department of Physiology & Pharmacology, Section of Anaesthesiology & Intensive Care, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Per-Arne
authors.initials: PA
authors.lastname: Lönnqvist
mesh_terms: D000577:Amides; D000762:Anesthesia Recovery Period; D000779:Anesthetics, Local; D002648:Child; D002675:Child, Preschool; D020927:Dexmedetomidine; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006552:Hernia, Inguinal / Q000601:surgery*; D006801:Humans; D006993:Hypnotics and Sedatives; D007223:Infant; D008297:Male; D009407:Nerve Block; D010149:Postoperative Pain / Q000188:drug therapy*; D011446:Prospective Studies; D000077212:Ropivacaine
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D006993:Hypnotics and Sedatives; D020927:Dexmedetomidine; D000077212:Ropivacaine
keywords: child; emergence delirium; local anesthetics; nerve block; pain; postanesthesia care unit