title: Non-weight-based enoxaparin dosing subtherapeutic in trauma patients.
abstract: BACKGROUND
  We report our experience dosing and monitoring enoxaparin with anti-factor Xa activity (anti-FXaA) levels for venous thromboembolism prophylaxis in trauma patients (TP).
  
  
  METHODS
  TP receiving standard, non-weight-based dosed enoxaparin administered every 12 h for venous thromboembolism prophylaxis with peak anti-FXaA levels measured were prospectively monitored and evaluated and those whose first anti-FXaA levels ≥ or <0.2 IU/mL were compared. Anti-FXaA levels and enoxaparin dose (mg/kg actual body weight) were evaluated for correlation.
  
  
  RESULTS
  Of the fifty-one TP included, initial anti-FXaA levels were <0.2 IU/mL in 37 (72.5%) whose dose was lower than those within target range (0.38 [0.32-0.42] mg/kg versus 0.45 [0.39-0.48] mg/kg, P = 0.003). Thirty-seven TP achieved anti-FXaA level ≥0.2 IU/mL (23 requiring dose increases) at a dose of 0.49 [0.44-0.54] mg/kg. Correlation between dose and anti-FXaA levels for the initial 51 anti-FXaA levels (r = 0.360, P = 0.009) and for all 103 anti-XaA levels (r = 0.556, P < 0.001) was noted.
  
  
  CONCLUSIONS
  Non-weight-based enoxaparin dosing did not achieve target anti-FXaA levels in most TP. Higher anti-FXaA levels correlated with larger weight-based enoxaparin doses. Weight-based enoxaparin dosing (i.e., 0.5 mg/kg subcutaneously every 12 h) would better achieve target anti-FXaA levels.
authors: Department of Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota; Department of Pharmacy Services, North Memorial Medical Center, Robbinsdale, Minnesota. Electronic address: chapm004@umn.edu.
authors: Scott A
authors: SA
authors: Chapman
authors: Department of Trauma Services, North Memorial Medical Center, Robbinsdale, Minnesota.
authors: Eric D
authors: ED
authors: Irwin
authors: Department of Trauma Services, North Memorial Medical Center, Robbinsdale, Minnesota.
authors: Patty
authors: P
authors: Reicks
authors: Department of Trauma Services, North Memorial Medical Center, Robbinsdale, Minnesota; Division of Acute and Critical Care Surgery, Department of Surgery, School of Medicine, Minneapolis, Minnesota.
authors: Gregory J
authors: GJ
authors: Beilman
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage*; D016903:Drug Monitoring / Q000379:methods*; D017984:Enoxaparin / Q000008:administration & dosage*; D015951:Factor Xa / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D054556:Venous Thromboembolism / Q000517:prevention & control*
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin; D015951:Factor Xa
keywords: Anti-factor Xa activity; Enoxaparin; Prophylaxis; Trauma; Venous thromboembolism