title: Evaluation of the platelet function analyzer (PFA-100) vs. the thromboelastogram (TEG) in the parturient.
abstract: BACKGROUND
  The platelet function analyzer (PFA-100) is a bedside test of coagulation designed to evaluate platelet function. It measures the time required for whole blood to occlude a membrane impregnated with either epinephrine (EPI) or adenosine 5'diphosphate (ADP). The results are reported as closure time (CT-EPI or CT-ADP) in seconds. The thromboelastogram (TEG) measures whole blood clotting and the maximum amplitude (MA) correlates with platelet count and function. We wished to establish whether there is a correlation between the CT and platelet count, between the CT and MA, and between the MA and platelet count.
  
  
  METHODS
  Platelet count, CT, and MA were measured in blood drawn from 172 healthy term parturients using the PFA-100.
  
  
  RESULTS
  We were unable to detect a significant correlation between the CT-EPI and platelet count (r=-0.1, P=0.21), or the CT-ADP and platelet count (r=-0.02, P=0.83). We also did not find a correlation between the CT-EPI and MA (r=-0.13, P=0.12) or between the CT-ADP and MA (r=-0.11, P=0.19). However, we found a significant correlation between platelet count and MA (r=0.33, P<0.001).
  
  
  CONCLUSIONS
  We conclude that the CT does not correlate with the platelet count or MA in the parturient, but the TEG does. Therefore the TEG may be a better tool to evaluate coagulation in the parturient with thrombocytopenia.
authors.affiliation: Department of Anesthesiology, Mount Sinai School of Medicine of New York University, New York, NY 10029-6574, USA. yaakov.beilin@mountsinai.org
authors.forename: Y
authors.initials: Y
authors.lastname: Beilin
authors.forename: I
authors.initials: I
authors.lastname: Arnold
authors.forename: S
authors.initials: S
authors.lastname: Hossain
mesh_terms: D000293:Adolescent; D000328:Adult; D000773:Anesthesia, Obstetrical; D001780:Blood Coagulation Tests / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008875:Middle Aged; D010976:Platelet Count; D010979:Platelet Function Tests / Q000295:instrumentation*; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000097:blood / Q000175:diagnosis*; D013916:Thrombelastography; D013921:Thrombocytopenia / Q000097:blood / Q000175:diagnosis*