title: Platelet Count Trends and Prevalence of Heparin-Induced Thrombocytopenia in a Cohort of Extracorporeal Membrane Oxygenator Patients.
abstract: OBJECTIVE
  To assess the prevalence of heparin-induced thrombocytopenia and to study platelet count trends potentially suggestive of heparin-induced thrombocytopenia in a population of extracorporeal membrane oxygenator patients.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  A total of 926-bed teaching hospital.
  
  
  METHODS
  Extracorporeal membrane oxygenator patients who survived longer than 48 hours from extracorporeal membrane oxygenator initiation between January 1, 2009, and December 31, 2013.
  
  
  METHODS
  None.
  
  
  RESULTS
  Demographic and clinical data were collected prospectively on all extracorporeal membrane oxygenator patients. Heparin-induced thrombocytopenia testing results and platelet count variables were obtained from the electronic medical record. We used our institutional algorithm to interpret the results of heparin-induced thrombocytopenia testing. Ninety-six extracorporeal membrane oxygenator patients met the inclusion criteria. Eight patients met the algorithm criteria for heparin-induced thrombocytopenia diagnosis and seven of those had documented thromboembolic event while on extracorporeal membrane oxygenator (prevalence of heparin-induced thrombocytopenia and heparin-induced thrombocytopenia related thrombosis, 8.3 and 7.3, respectively). Heparin-induced thrombocytopenia positive patients were younger; all underwent venoarterial extracorporeal membrane oxygenator; spent more hours on extracorporeal membrane oxygenator; had significantly higher heparin-induced thrombocytopenia enzyme-linked immunosorbent assays optical density; had a higher prevalence of thromboembolic events and reached platelet count nadir later. There was no difference in mortality between heparin-induced thrombocytopenia positive and negative patients. Comparison of platelet count trends revealed that there was no statistically significant difference between the predefined study groups.
  
  
  CONCLUSIONS
  Prevalence of heparin-induced thrombocytopenia and heparin-induced thrombocytopenia-related thrombosis among extracorporeal membrane oxygenator patients at our institution is relatively high. Using platelet count trends to guide decision to test for heparin-induced thrombocytopenia is not an optimal strategy in extracorporeal membrane oxygenator patients. Without a validated pretest probability clinical score, serosurveillance in a defined high-risk group of extracorporeal membrane oxygenator patients may be needed.
authors.affiliation: 1Surgical Critical Care Service, Department of Surgery, Medstar Washington Hospital Center, Washington, DC. 2Department of Anesthesia, Resuscitation and Intensive Care, University Clinical Center, Kragujevac, Serbia.
authors.forename: Mladen
authors.initials: M
authors.lastname: Sokolovic
authors.forename: Alexandra K
authors.initials: AK
authors.lastname: Pratt
authors.forename: Vladimir
authors.initials: V
authors.lastname: Vukicevic
authors.forename: Molly
authors.initials: M
authors.lastname: Sarumi
authors.forename: Laura S
authors.initials: LS
authors.lastname: Johnson
authors.forename: Nimesh S
authors.initials: NS
authors.lastname: Shah
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000009:adverse effects*; D015331:Cohort Studies; D004797:Enzyme-Linked Immunosorbent Assay; D015199:Extracorporeal Membrane Oxygenation / Q000706:statistics & numerical data; D005260:Female; D006493:Heparin / Q000009:adverse effects*; D006784:Hospitals, Teaching; D006801:Humans; D007511:Ischemia / Q000150:complications; D008297:Male; D008875:Middle Aged; D010976:Platelet Count / Q000639:trends; D015995:Prevalence; D012189:Retrospective Studies; D020521:Stroke / Q000150:complications; D013921:Thrombocytopenia / Q000139:chemically induced* / Q000150:complications / Q000453:epidemiology; D013923:Thromboembolism / Q000150:complications
chemical_list: D000925:Anticoagulants; D006493:Heparin