title: Pre- and Post-Bypass Platelet Function Testing With Multiple Electrode Aggregometry and TEG Platelet Mapping in Cardiac Surgery.
abstract: OBJECTIVE
  To investigate the differences between pre- and post-cardiopulmonary bypass platelet function tests and to examine whether post-bypass tests could predict postoperative bleeding.
  
  
  METHODS
  A prospective cohort study.
  
  
  METHODS
  A tertiary cardiothoracic center.
  
  
  METHODS
  Fifty-four patients presenting for cardiac surgery.
  
  
  METHODS
  Pre- and post-bypass platelet function tests with TEG Platelet Mapping (PM) and Multiple Electrode Aggregometry (Multiplate - MEA) were performed.
  
  
  RESULTS
  The results of the paired samples were compared. Outcomes including blood loss in the first 4 and 12 hours postoperatively and requirement for resternotomy also were recorded and regression analyses performed to establish predictive factors. Tests using adenosine diphosphate (ADP) and arachidonic acid as stimulators for platelet aggregation showed significant differences pre- and post-bypass, with both MEA and PM showing greater inhibition in platelet function after bypass (p<0.01). However, there was no significant change in MEA TRAP values with cardiopulmonary bypass (p = 0.79) There was no relationship between post-bypass platelet function and the reduction in measured platelet function and blood loss in the postoperative period.
  
  
  CONCLUSIONS
  Post-bypass platelet function testing showed reductions in ADP and arachidonic acid-triggered aggregation but not in TRAP-triggered aggregation compared with pre-bypass testing. There was no relationship between the post-bypass tests and bleeding.
authors.affiliation: Liverpool Heart and Chest Hospital, Liverpool, UK. Electronic address: Seema.Agarwal@lhch.nhs.uk.
authors.forename: Seema
authors.initials: S
authors.lastname: Agarwal
authors.affiliation: Liverpool Heart and Chest Hospital, Liverpool, UK.
authors.forename: Robert Ian
authors.initials: RI
authors.lastname: Johnson
authors.affiliation: Liverpool Heart and Chest Hospital, Liverpool, UK.
authors.forename: Bilal Haneef
authors.initials: BH
authors.lastname: Kirmani
mesh_terms: D000368:Aged; D001792:Blood Platelets / Q000502:physiology*; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000601:surgery; D004566:Electrodes; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D059035:Perioperative Period; D010974:Platelet Aggregation / Q000502:physiology*; D010979:Platelet Function Tests; D019106:Postoperative Hemorrhage / Q000097:blood* / Q000517:prevention & control; D011379:Prognosis; D011446:Prospective Studies; D013916:Thrombelastography / Q000295:instrumentation*
keywords: cardiac surgery; platelet function tests; thromboelastography