title: Dexmedetomidine decreases the required amount of bupivacaine for ultrasound-guided transversus abdominis plane block in pediatrics patients: a randomized study.
abstract: BACKGROUND
  The effect of dexmedetomidine on the potency of bupivacaine for transversus abdominis plane (TAP) block in pediatric patients has not been investigated.
  
  
  OBJECTIVE
  The primary objective of this study was to assess the effectiveness of dexmedetomidine to decrease the concentration of bupivacaine needed for analgesia for ultrasound-guided TAP block in a pediatric patient undergoing hernia repair or hydrocelectomy.
  
  
  METHODS
  This is a randomized, double-blind, up-down, dose-finding study.
  
  
  METHODS
  Operating room.
  
  
  METHODS
  Sixty American Society of Anesthesiologists I and II patients aged 1-4 years scheduled for elective unilateral herniorrhaphy or hydrocelectomy.
  
  
  METHODS
  Patients were randomly assigned to 1 of the 2 groups: group B (0.125% bupivacaine, 1mL/kg) TAP block or group BD (0.125% bupivacaine plus 2μg/kg dexmedetomidine, 1mL/kg) TAP block.
  
  
  METHODS
  The response of each child was observed for 60 seconds after skin incision and evaluated as 'unsuccessful' when skin incision caused a change in hemodynamic parameters (heart rate and mean blood pressure) 20% more than the preincision values. If the response was determined to be unsuccessful, the concentration of bupivacaine administrated to the next patient was increased by 0.02%. If it was successful, the concentration of bupivacaine administrated to the next patient was decreased by 0.02%.
  
  
  RESULTS
  The minimum local anesthetic concentration of bupivacaine was 0.0839% (0.0137) in the B group and 0.0550% (0.0169) in the BD group. The difference was statistically significant (t=7.165, P=.0001). The total postoperative analgesic dosage of morphine was significantly higher in the B group (0.17±0.04 mg/kg) than the BD group (0.11±0.02 mg/kg, P=.001).
  
  
  CONCLUSIONS
  The addition of 2μg/kg of dexmedetomidine reduced the minimum local anesthetic concentration of bupivacaine used for a TAP block and improved postoperative analgesia in children undergoing surgery for inguinal hernia repair or hydrocelectomy.
authors.affiliation: Department of Anesthesia and Surgical Intensive Care, Faculty of Medicine, Alexandria University, Egypt.
authors.forename: Rehab Abdel
authors.initials: RA
authors.lastname: Raof
authors.affiliation: Department of Anesthesia and Surgical Intensive Care, Faculty of Medicine, Alexandria University, Egypt. Electronic address: shelmetainy@yahoo.com.
authors.forename: Shahira Ahmed
authors.initials: SA
authors.lastname: El Metainy
authors.affiliation: Department of Anesthesia and Surgical Intensive Care, Faculty of Medicine, Alexandria University, Egypt.
authors.forename: Doaa Abou
authors.initials: DA
authors.lastname: Alia
authors.affiliation: Department of Biostatistics, High Institute of Public Health Alexandria University, Egypt.
authors.forename: Moataza Abdel
authors.initials: MA
authors.lastname: Wahab
mesh_terms: D000009:Abdominal Muscles; D058647:Adrenergic alpha-2 Receptor Agonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001794:Blood Pressure; D002045:Bupivacaine / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D002675:Child, Preschool; D020927:Dexmedetomidine / Q000008:administration & dosage / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D006339:Heart Rate; D006552:Hernia, Inguinal / Q000601:surgery; D059685:Herniorrhaphy / Q000009:adverse effects; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000627:therapeutic use*; D007223:Infant; D008297:Male; D009407:Nerve Block / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control*; D011446:Prospective Studies; D011897:Random Allocation; D006848:Testicular Hydrocele / Q000601:surgery; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D058647:Adrenergic alpha-2 Receptor Agonists; D000779:Anesthetics, Local; D006993:Hypnotics and Sedatives; D020927:Dexmedetomidine; D002045:Bupivacaine
keywords: Adjuvants, anesthesia; Nerve block; Pain, postoperative; Ultrasonography, local