title: Anti-Factor Xa Activity of Prophylactic Enoxaparin Regimens in Critically Ill Patients.
abstract: BACKGROUND
  Enoxaparin is frequently used as prophylaxis for deep venous thrombosis in critically ill patients.
  
  
  OBJECTIVE
  To evaluate three enoxaparin prophylactic regimens in critical care patients with and without administration of a vasopressor.
  
  
  METHODS
  Patients admitted to intensive care units (general and post-cardiothoracic surgery) without renal failure received, once daily, a subcutaneous fixed dose of 40 mg enoxaparin, a subcutaneous dose of 0.5 mg/kg enoxaparin, or an intravenous dose of 0.5 mg/kg enoxaparin. Over 5 days anti-activated factor X levels were collected before the daily administration and 4 hours after the injection.
  
  
  RESULTS
  Overall, 16 patients received the subcutaneous fixed dose, 15 received the subcutaneous weight-based dosage, and 8 received the dose intravenously. Around two-fifths (38%) of the patients received vasopressors. There was no difference between anti-activated factor X levels regarding vasopressor administration. However, in all three groups the levels were outside the recommended range of 0.1 IU/ml and 0.3 IU/ml.
  
  
  CONCLUSIONS
  Although not influenced by vasopressor administration, the enoxaparin regimens resulted in blood activity levels outside the recommended range.
authors.forename: Yigal
authors.initials: Y
authors.lastname: Helviz
authors.forename: Ilia
authors.initials: I
authors.lastname: Dzigivker
authors.forename: David
authors.initials: D
authors.lastname: Raveh-Brawer
authors.forename: Moshe
authors.initials: M
authors.lastname: Hersch
authors.forename: Shoshana
authors.initials: S
authors.lastname: Zevin
authors.forename: Sharon
authors.initials: S
authors.lastname: Einav
mesh_terms: D061605:Administration, Intravenous; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000494:pharmacology / Q000627:therapeutic use*; D016638:Critical Illness; D004305:Dose-Response Relationship, Drug; D017984:Enoxaparin / Q000494:pharmacology / Q000627:therapeutic use*; D015951:Factor Xa / Q000187:drug effects; D065427:Factor Xa Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007279:Injections, Subcutaneous; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014662:Vasoconstrictor Agents / Q000008:administration & dosage; D020246:Venous Thrombosis / Q000517:prevention & control*
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin; D065427:Factor Xa Inhibitors; D014662:Vasoconstrictor Agents; D015951:Factor Xa