title: Unsuspected coagulopathy rarely prevents IV thrombolysis in acute ischemic stroke.
abstract: BACKGROUND
  American Heart Association/American Stroke Association guidelines recommend initiating treatment with IV tissue plasminogen activator (tPA) in acute ischemic stroke patients without suspected coagulopathy prior to availability of clotting results; however, little or no data support this practice. We sought to identify how often blood clotting abnormalities were responsible for withholding IV tPA at our institution.
  
  
  METHODS
  We conducted a retrospective review of our prospectively acquired Get With the Guidelines Stroke database from January 2003 to April 2008. All patients underwent clinical evaluation by a neurologist, diagnostic neuroimaging, and laboratory testing on admission. We classified patients with absolute contraindications to IV tPA as ineligible, and those with warnings/relative contraindications or potentially treatable factors as potentially eligible.
  
  
  RESULTS
  Of 2,335 considered for analysis, 470 (20.1%) patients presented to our emergency department (ED) within 3 hours. Among these, 147 (31.3%) received IV tPA in our ED, 102 (21.7%) had an absolute contraindication, and 221 (47%) had a reason to consider withholding tPA. Only 30/470 (6.4%) of potential thrombolysis patients were discovered to have international normalized ratio > or =1.7 or platelets < or =100,000/microL, and of these, 28 were suspected a priori due to known coagulopathy from medication or illness. Only 2/470 (0.4%) patients had an unsuspected coagulopathy that ultimately prevented thrombolysis.
  
  
  CONCLUSIONS
  Based on the experience of a large thrombolysis referral center, stroke patients without suspected clotting abnormality can safely begin thrombolytic therapy before clotting results are available. These data support the current practice guidelines, and may reassure clinicians that the benefits of early administration greatly outweigh the risks due to an unsuspected bleeding diathesis.
authors: Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA. nrost@partners.org
authors: N S
authors: NS
authors: Rost
authors: S
authors: S
authors: Masrur
authors: M A
authors: MA
authors: Pervez
authors: A
authors: A
authors: Viswanathan
authors: L H
authors: LH
authors: Schwamm
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001778:Blood Coagulation Disorders / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy*; D002545:Brain Ischemia / Q000150:complications / Q000188:drug therapy*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012042:Registries; D012189:Retrospective Studies; D020521:Stroke / Q000150:complications / Q000188:drug therapy*; D015912:Thrombolytic Therapy / Q000379:methods; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*
chemical_list: D010959:Tissue Plasminogen Activator