title: Reduction of topical anesthetic onset time using ultrasound: a randomized controlled trial prior to venipuncture in young children.
abstract: BACKGROUND
  Ultrasound treatment prior to topical anesthetic application has been shown to speed anesthesia onset by enhancing anesthetic penetration into the skin.
  
  
  OBJECTIVE
  To evaluate a low-frequency ultrasound device to facilitate absorption of topical anesthetic in young children who require venipuncture.
  
  
  METHODS
  This was a prospective controlled comparison of analgesic effect of a 5-minute application of liposomal lidocaine cream after ultrasound treatment, with a 30-minute application of liposomal lidocaine cream, in children aged 3 to 7 years undergoing venipuncture. Children rated the pain of the venipuncture using the Wong-Baker FACES Pain Rating Scale (FACES) (0 = no pain, 10 = maximal pain), and parents rated their child's pain using a 100-mm (0 = no pain, 100 = maximal pain) visual analogue scale (VAS). Venipuncture skin sites were evaluated for effect immediately posttreatment, and at 24 to 72 hours post phlebotomy.
  
  
  RESULTS
  Seventy subjects were enrolled: the first 10 patients comprised a pilot series, receiving the ultrasonic treatment and liposomal lidocaine cream; the next 60 subjects were randomized, including 29 allocated to the ultrasound treatment group, and 31 randomized to the 30-minute control treatment with liposomal lidocaine cream. Demographics were similar between the two groups. Mean child's FACES scale results were similar: Ultrasound group 4.78 (95% CI; 3.06, 6.52), CONTROL group 4.32 (95% CI; 2.82, 5.82) (P = 0.72); and mean parent VAS scores were also the same: Ultrasound: 19.1 (95% CI; 10.3, 27.8), CONTROL: 23.2 (95% CI; 14.7, 31.7) (P = 0.87). Skin effects immediately after ultrasound were limited to minor redness in 9/39 children and significant redness in 2/29 patients.
  
  
  CONCLUSIONS
  Ultrasound treatment speeds time of onset of liposomal lidocaine cream anesthesia in young children undergoing venipuncture. Side effects were mild in our population.
authors.affiliation: Pain Relief Program, Department of Pediatrics, University of Connecticut School of Medicine, Hartford, Connecticut, USA. wzempsk@ccmckids.org
authors.forename: William T
authors.initials: WT
authors.lastname: Zempsky
authors.forename: Bertha
authors.initials: B
authors.lastname: Robbins
authors.forename: Kathleen
authors.initials: K
authors.lastname: McKay
mesh_terms: D000287:Administration, Topical; D000779:Anesthetics, Local / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage*; D008297:Male; D010146:Pain / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control*; D010147:Pain Measurement / Q000187:drug effects; D018962:Phlebotomy / Q000009:adverse effects* / Q000379:methods*; D013010:Sonication; D013997:Time Factors; D016896:Treatment Outcome; D014464:Ultrasonic Therapy / Q000379:methods*
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine