title: Enoxaparin dosing after cesarean delivery in morbidly obese women.
abstract: OBJECTIVE
  To compare the adequacy of venous thromboembolism prophylaxis based on anti-Xa concentrations between weight-based enoxaparin dosing and body mass index (BMI)-stratified dosing in morbidly obese women after cesarean delivery.
  
  
  METHODS
  A prospective sequential cohort study of women with BMIs of 40 or greater who underwent cesarean delivery was conducted. Participants received either weight-based or BMI-stratified enoxaparin dosing to prevent venous thromboembolism formation. The weight-based regimen was 0.5 mg/kg of enoxaparin every 12 hours. In the BMI-stratified regimen, women with BMIs of 40-59.9 received 40 mg enoxaparin every 12 hours and women with BMIs of 60 or greater received 60 mg every 12 hours. The primary outcome was an anti-Xa concentration in the adequate thromboprophylaxis range (0.2-0.6 international units/mL). Secondary outcomes included enoxaparin dosage, timing of dosing and anti-Xa concentration, estimated surgical blood loss, postoperative changes in hemoglobin and platelets, wound hematoma, and adverse reactions to enoxaparin. Univariate analysis was used to compare dosing regimens.
  
  
  RESULTS
  Forty-two morbidly obese women received weight-based enoxaparin, and 43 received BMI-stratified dosing. Anti-Xa concentrations were significantly higher in the weight-based group compared with the BMI-stratified group (0.29±0.08 international units/mL compared with 0.17±0.07 international units/mL, P<.001). Thirty-six participants (86%) on weight-based dosing had anti-Xa concentrations within the prophylactic range compared with 11 (26%) on BMI-stratified dosing (P<.001). No participant had an anti-Xa concentration of 0.6 international units/mL or greater, the therapeutic threshold for venous thromboembolism prophylaxis.
  
  
  CONCLUSIONS
  In morbidly obese women after cesarean delivery, weight-based dosing of enoxaparin for venous thromboembolism prophylaxis is significantly more effective than BMI-stratified dosing in achieving adequate anti-Xa concentrations.
  
  
  METHODS
  II.
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Reproductive Medicine, the Department of Pharmacy, and the Division of Obstetrics and Gynecology, Department of Reproductive Medicine, University of California San Diego, San Diego, California.
authors.forename: Rachael T
authors.initials: RT
authors.lastname: Overcash
authors.forename: Alicia T
authors.initials: AT
authors.lastname: Somers
authors.forename: D Yvette
authors.initials: DY
authors.lastname: LaCoursiere
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D015992:Body Mass Index; D001835:Body Weight; D002585:Cesarean Section / Q000009:adverse effects*; D054796:Drug Dosage Calculations; D016903:Drug Monitoring; D017984:Enoxaparin / Q000008:administration & dosage* / Q000009:adverse effects; D065427:Factor Xa Inhibitors / Q000097:blood*; D005260:Female; D006406:Hematoma / Q000139:chemically induced; D006801:Humans; D009767:Obesity, Morbid / Q000150:complications*; D011247:Pregnancy; D011248:Pregnancy Complications; D011446:Prospective Studies; D054556:Venous Thromboembolism / Q000209:etiology / Q000517:prevention & control*; D014845:Vulvar Diseases / Q000139:chemically induced; D055815:Young Adult
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin; D065427:Factor Xa Inhibitors