title: Prolonged transcranial Doppler monitoring after aneurysmal subarachnoid hemorrhage fails to adequately predict ischemic risk.
abstract: BACKGROUND
  Stroke is common after aneurysmal subarachnoid hemorrhage (aSAH). Transcranial Doppler ultrasound (TCD) monitoring is often employed to identify vasospasm and allow intervention to avoid infarction. The required duration of monitoring has not been established. We aim to determine if 10 days of TCD monitoring identifies all patients at risk for infarction.
  
  
  METHODS
  A 3 year retrospective analysis of aSAH patients admitted to a neurovascular center was undertaken. Eligible patients were aged 18-85 years, presenting within 2 days of hemorrhage who had underwent TCD monitoring through post bleed day 10. Patients were assessed to determine if vasospasm onset occurred after 10 days with resulting stroke. Assessment of variables potentially impacting vasospasm onset and infarction were completed.
  
  
  RESULTS
  107 patients met criteria with 51 (48%) demonstrating vasospasm and 31 (29%) developing stroke. Of those suffering stroke, 22 (71%) demonstrated vasospasm while 9 (22%) did not. Two (2%) patients developed vasospasm only after day 10, neither experiencing stroke. Time to vasospasm onset (5.5 ± 2.5 days) was not impacted by common radiologic or clinical scales. Glasgow Coma Scale (GCS), Hunt and Hess Score (H&H), WFNS, ventriculostomy placement, intubation, and intraventricular hemorrhage were associated with likelihood of stroke (P < 0.05). The negative predictive value of TCD for identifying stroke risk was 84% while the sensitivity was 71%.
  
  
  CONCLUSIONS
  TCD identification of vasospasm after day 10 is rare. Stroke is more likely to result from poor detection than from brevity of TCD monitoring. Improved or alternative monitoring is needed to effectively identify ischemia and prevent stroke.
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, 8631 West Third Street, Suite 800E, Los Angeles, CA 90048, USA. millercm@cshs.org
authors.forename: Chad M
authors.initials: CM
authors.lastname: Miller
authors.forename: David
authors.initials: D
authors.lastname: Palestrant
authors.forename: Wouter I
authors.initials: WI
authors.lastname: Schievink
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Alexander
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000628:therapy; D002544:Cerebral Infarction / Q000000981:diagnostic imaging / Q000517:prevention & control; D015331:Cohort Studies; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D011237:Predictive Value of Tests; D012307:Risk Factors; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000628:therapy; D013525:Surgical Instruments; D014057:Tomography, X-Ray Computed; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging* / Q000628:therapy