title: Quantifying the Benefit of Prehospital Rapid Treatment in Acute Stroke: Benchmark for Future Innovative Clinical Trials.
abstract: OBJECTIVE
  In acute ischemic stroke, time from onset to tissue-type plasminogen activator treatment (OTT) is a major determinant of outcome. To reduce OTT, clinical trials have been undertaken evaluating prehospital cerebral imaging with mobile computed tomographic scanners. Furthermore, blood biomarkers may allow rapid differentiation between ischemic stroke and intracerebral hemorrhage before hospital admission. How such treatment strategies translate into clinical benefit has not been specifically evaluated.
  
  
  METHODS
  We constructed decision models to estimate the net clinical benefit yielded by shorter OTT. In different scenarios, we estimated the proportion of patients with favorable outcome and the average quality of life.
  
  
  RESULTS
  An OTT reduction of 60 minutes increases the probability of favorable outcome by 6.6% in a mixed stroke population. For comparison, the average effect of tissue-type plasminogen activator itself is 7.0%. Prehospital mobile computed tomography gaining 25 to 40 minutes increases the probability of favorable outcome by 3.0% to 4.6%. The additional benefit of prehospital computed tomography to deliver patients with large vessel occlusion directly to endovascular treatment centers increases the probability of favorable outcome by another 0.2% to 1.0%. A blood test discriminating ischemic stroke and intracerebral hemorrhage may beneficially substitute brain scan before tissue-type plasminogen activator if >32 to 40 minutes are gained and if sensitivity for intracerebral hemorrhage is >75% to 80%.
  
  
  CONCLUSIONS
  Reducing the OTT has robust beneficial effects for acute stroke patients. Prehospital tissue-type plasminogen activator treatment without brain imaging may become conceivable under several preconditions, including a point-of-care test with >75% to 80% sensitivity to detect intracerebral hemorrhage and a time gain of >32 to 40 minutes. Ethical implications remain to be addressed.
authors.affiliation: From the Department of Neurology, University Hospital Frankfurt, Frankfurt/Main, Germany. matthias.lorenz@em.uni-frankfurt.de.
authors.forename: Matthias W
authors.initials: MW
authors.lastname: Lorenz
authors.affiliation: From the Department of Neurology, University Hospital Frankfurt, Frankfurt/Main, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Lauer
authors.affiliation: From the Department of Neurology, University Hospital Frankfurt, Frankfurt/Main, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Foerch
mesh_terms: D019985:Benchmarking; D015415:Biomarkers / Q000097:blood; D002545:Brain Ischemia / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy*; D002543:Cerebral Hemorrhage / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging; D003661:Decision Support Techniques; D061345:Early Medical Intervention / Q000379:methods; D004632:Emergency Medical Services / Q000379:methods*; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D019095:Point-of-Care Systems; D011788:Quality of Life; D020521:Stroke / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000209:etiology; D015912:Thrombolytic Therapy / Q000379:methods; D061665:Time-to-Treatment; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator
keywords: acute stroke; benefit; stroke biomarker; thrombolysis; time gain