title: Dexmedetomidine offers an option for safe and effective sedation for nuclear medicine imaging in children.
abstract: OBJECTIVE
  To determine the safety, efficacy, and outcomes of bradycardia, hypotension, and hypertension with dexmedetomidine (DEX), a recently approved sedative used for procedural sedation that has not been described previously for pediatric nuclear medicine imaging.
  
  
  METHODS
  Between March 2005 and August 2011, 669 patients (mean age, 5.7 years ± 4.5 [standard deviation]; median age, 4.5 years; age range, 0.1-22.5 years) received DEX in this HIPAA-compliant study. Sedation was administered with DEX, an α-2 adrenergic agonist, as an intravenous bolus (2 μg per kilogram of body weight) over a 10-minute period; this was followed by continuous infusion at a rate of 1 μg/kg/h until imaging was complete. The bolus could be repeated up to two times, if needed, to achieve the targeted level of a Ramsay sedation score of 4. After institutional review board approval, collected quality assurance data were reviewed.
  
  
  RESULTS
  Adequate sedation was achieved within 8.6 minutes ± 4.6 (median, 8.0 minutes; range, 1.0-40.0 minutes) on average in studies that averaged 41.3 minutes ± 25.5 (median, 31.5 minutes; range, 9.0-183.0 minutes). Of 669 studies, 667 (99.7%) were completed successfully. Six children (0.9%) had brief periods of oxygen desaturation below 95%, none of which required airway intervention. Hypotension, hypertension, and bradycardia (all defined as deviations of more than 20% from age-adjusted awake norms), occurred in 58.7% (n = 393), 2.1% (n = 14), and 4.3% (n = 29) of patients, respectively. Both hypotension and bradycardia were related to age (P = .033 and P = .002, respectively); older children tended to experience more of these events. None of these fluctuations required pharmacologic therapy. Discharge criteria (modified Aldrete score ≥ 9) were met, on average, within 41.4 minutes ± 27.9 (median, 36.0 minutes; range, 1.0-220.0 minutes).
  
  
  CONCLUSIONS
  DEX offers advantages for pediatric sedation for nuclear medicine imaging. DEX produces a condition similar to natural sleep, with no detrimental effect on respiration. The hemodynamic variability anticipated with DEX did not require pharmacologic treatment, and the drug was well tolerated.
authors: Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Harvard Medical School, 300 Longwood Ave, Boston, MA 02115, USA. keira.mason@childrens.harvard.edu
authors: Keira P
authors: KP
authors: Mason
authors: Fay
authors: F
authors: Robinson
authors: Paulette
authors: P
authors: Fontaine
authors: Randy
authors: R
authors: Prescilla
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001919:Bradycardia / Q000139:chemically induced; D002648:Child; D002675:Child, Preschool; D002985:Clinical Protocols; D020927:Dexmedetomidine / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000139:chemically induced; D006993:Hypnotics and Sedatives / Q000008:administration & dosage* / Q000009:adverse effects; D007022:Hypotension / Q000139:chemically induced; D007223:Infant; D016015:Logistic Models; D008297:Male; D061214:Patient Safety; D049268:Positron-Emission Tomography; D055815:Young Adult
chemical_list: D006993:Hypnotics and Sedatives; D020927:Dexmedetomidine