title: Thromboelastography Parameter Predicts Outcome After Subarachnoid Hemorrhage: An Exploratory Analysis.
abstract: OBJECTIVE
  Hypercoagulability after subarachnoid hemorrhage (SAH) is well described and may be platelet mediated. Thromboelastography (TEG) provides a global assessment of coagulation. We sought to determine whether the maximum amplitude (MA) parameter of TEG, a measure of platelet strength and function, is associated with outcome after SAH.
  
  
  METHODS
  One hundred ten TEG analyses were performed for patients with moderate-to-severe SAH and compared with 6 healthy age- and sex-matched controls. TEG indices included MA, G value (G), alpha angle, and thrombus generation and were correlated to functional outcomes and laboratory tests including complete blood count, erythrocyte sedimentation rate, high sensitivity C-reactive protein, fibrinogen, and d-dimer, obtained on post-bleed days (PBDs) 1, 3, 5, 7, and 10.
  
  
  RESULTS
  MA was significantly elevated compared with controls on PBD 3 (70.0 mm ± 4.5 mm vs. 64.1 mm ± 6.5 mm; P = 0.02), PBD 5 (72.6 mm ± 5.3 mm vs. 64.1 mm ± 6.5 mm; P = 0.003), PBD 7 (73.0 mm ± 5.4 mm vs. 64.1 mm ± 6.5 mm; P = 0.003), and PBD 10 (73.4 mm ± 6.0 mm vs. 64.1 mm ± 6.5 mm; P = 0.005). G was significantly elevated compared with controls on PBD 3 (P = 0.03), PBD 5 (P = 0.01), PBD 7 (P = 0.01), and PBD 10 (P = 0.02). The only biomarker associated with poor outcome was CRP. Multivariate logistic regression demonstrated an association between elevated MA and outcome (odds ratio 39.1, P = 0.006) independent of CRP, age, Hunt Hess grade, and transfusion.
  
  
  CONCLUSIONS
  TEG indices are associated with poor outcome after SAH and may identify a platelet-mediated hypercoagulable state. The association between MA and outcome was stronger than that between traditional biomarkers and was independent of age and Hunt Hess grade.
authors.affiliation: Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Preethi
authors.initials: P
authors.lastname: Ramchand
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Nyirjesy
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Frangos
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Sean
authors.initials: S
authors.lastname: Doerfler
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Kelsey
authors.initials: K
authors.lastname: Nawalinski
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Francis
authors.initials: F
authors.lastname: Quattrone
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Connie
authors.initials: C
authors.lastname: Ju
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Hiren
authors.initials: H
authors.lastname: Patel
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Nicki
authors.initials: N
authors.lastname: Driscoll
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Eileen
authors.initials: E
authors.lastname: Maloney-Wilensky
authors.affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Sherman C
authors.initials: SC
authors.lastname: Stein
authors.affiliation: Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Levine
authors.affiliation: Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Scott E
authors.initials: SE
authors.lastname: Kasner
authors.affiliation: Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, USA. Electronic address: Monisha.Kumar@uphs.upenn.edu.
authors.forename: Monisha A
authors.initials: MA
authors.lastname: Kumar
mesh_terms: D000368:Aged; D001777:Blood Coagulation / Q000502:physiology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D013345:Subarachnoid Hemorrhage / Q000175:diagnosis* / Q000503:physiopathology*; D013916:Thrombelastography / Q000379:methods*
keywords: Coagulopathy; Functional outcome; Hypercoagulable state; Platelet; Subarachnoid hemorrhage; Thromboeleastography