title: Adenosine-induced flow arrest to facilitate intracranial aneurysm clip ligation: dose-response data and safety profile.
abstract: BACKGROUND
  Adenosine-induced transient flow arrest has been used to facilitate clip ligation of intracranial aneurysms. However, the starting dose that is most likely to produce an adequate duration of profound hypotension remains unclear. We reviewed our experience to determine the dose-response relationship and apparent perioperative safety profile of adenosine in intracranial aneurysm patients.
  
  
  METHODS
  This case series describes 24 aneurysm clip ligation procedures performed under an anesthetic consisting of remifentanil, low-dose volatile anesthetic, and propofol in which adenosine was used. The report focuses on the doses administered; duration of systolic blood pressure <60 mm Hg (SBP(<60 mm Hg)); and any cardiovascular, neurologic, or pulmonary complications observed in the perioperative period.
  
  
  RESULTS
  A median dose of 0.34 mg/kg ideal body weight (range: 0.29-0.44 mg/kg) resulted in a SBP(<60 mm Hg) for a median of 57 seconds (range: 26-105 seconds). There was a linear relationship between the log-transformed dose of adenosine and the duration of a SBP(<60 mm Hg) (R(2) = 0.38). Two patients developed transient, hemodynamically stable atrial fibrillation, 2 had postoperative troponin levels >0.03 ng/mL without any evidence of cardiac dysfunction, and 3 had postoperative neurologic changes.
  
  
  CONCLUSIONS
  For intracranial aneurysms in which temporary occlusion is impractical or difficult, adenosine is capable of providing brief periods of profound systemic hypotension with low perioperative morbidity. On the basis of these data, a dose of 0.3 to 0.4 mg/kg ideal body weight may be the recommended starting dose to achieve approximately 45 seconds of profound systemic hypotension during a remifentanil/low-dose volatile anesthetic with propofol induced burst suppression.
authors.affiliation: Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: John F
authors.initials: JF
authors.lastname: Bebawy
authors.forename: Dhanesh K
authors.initials: DK
authors.lastname: Gupta
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Bendok
authors.forename: Laura B
authors.initials: LB
authors.lastname: Hemmer
authors.forename: Carine
authors.initials: C
authors.lastname: Zeeni
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Avram
authors.forename: H Hunt
authors.initials: HH
authors.lastname: Batjer
authors.forename: Antoun
authors.initials: A
authors.lastname: Koht
mesh_terms: D000241:Adenosine / Q000009:adverse effects / Q000494:pharmacology*; D000328:Adult; D000368:Aged; D000768:Anesthesia, General; D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D001281:Atrial Fibrillation / Q000209:etiology; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology; D002560:Cerebrovascular Circulation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000601:surgery*; D008026:Ligation; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000453:epidemiology / Q000209:etiology; D019635:Neurosurgical Procedures; D010880:Piperidines; D011183:Postoperative Complications / Q000453:epidemiology; D015742:Propofol; D000077208:Remifentanil; D014665:Vasodilator Agents / Q000009:adverse effects / Q000494:pharmacology*
chemical_list: D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D010880:Piperidines; D014665:Vasodilator Agents; D000241:Adenosine; D000077208:Remifentanil; D015742:Propofol