Comparing Anti-XA Levels in Post-Cesarean Patients Undergoing Enoxaparin Thromboprophylaxis
Condition: Obesity; Obesity, Morbid; Pregnancy; Complications; Cesarean Section; Venous Thromboembolism; Postpartum Deep Phlebothrombosis; Pulmonary Embolism
MeSH terms: Pulmonary Embolism; Embolism; Thromboembolism; Venous Thromboembolism; Venous Thrombosis; Obesity; Obesity, Morbid
Intervention: Enoxaparin
Intervention description: Enoxaparin will be given in either once daily or twice daily doses. One arm will receive 40 mg enoxaparin subcutaneous injection daily. The other arm will receive 0.5 mg/kg dosed subcutaneously twice daily. This medication will be started 8-12 hours after cesarean section and will be continued while the patient is admitted. It will be stopped at the time of discharge.
Intervention MeSH terms: Enoxaparin
Phase: Phase 1
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Enrollment: 90.0
Sex: Female
Minimum age: 18 Years
Healthy volunteers: Accepts Healthy Volunteers
Keywords: Obesity; Obesity, Morbid; Pregnancy; Cesarean; Venous thromboembolism; Deep venous thrombosis; Pulmonary embolism

Summary:

      Pregnant and recently postpartum women are at significantly higher risk of developing a blood
      clot in their arms or legs known as a deep venous thrombosis (DVT) and/or a blood clot in
      their lungs known as a pulmonary embolism (PE) compared to their non pregnant counterparts.
      It is estimated that this risk increases anywhere from 4 to 50 times higher in pregnant
      versus non-pregnant women and further increases almost 11 fold in the post partum period.
      This risk is almost doubled when the patient undergoes cesarean delivery. In 2011, the
      American College of Obstetricians and Gynecologists (ACOG) issued updated guidelines stating
      that for patients undergoing cesarean delivery with additional risk factors for clot or
      thromboembolism, protective (prophylactic) treatment with low molecular weight heparin (LMWH)
      a type of blood thinner should be considered. However, no specific guidelines about which
      risk factors should be considered, or what medication doses should be used were provided. The
      American College of Chest Physicians (ACCP) Evidence-Based Clinical Practice Guidelines
      published in 2012 delineated who should be given prophylaxis based on various risk factors,
      however acknowledged that the recommendations were based on weak quality evidence.

      ACOG endorses either once or twice a day dosing for high risk patients after delivery and
      states that adjustments for obese women should be made on a case by case basis. However,
      there are limited studies on the dosing of LMWH in specific subpopulations including post
      operative patients, pregnant patients and obese patients. All of these studies have urged
      further investigation of the correct dosing for these high risk subjects due to changes
      associated with pregnancy and the level of medication in the blood that may put these
      patients at higher risk of venous thromboembolism. Many previous studies have shown that
      women in these high risk categories do not achieve protective levels of the medication
      measured with a laboratory test; anti Xa level. The investigators hypothesize that due to
      their dual risk, obese post-operative recently pregnant women may not be adequately protected
      with the daily fixed dose and might need more frequent dosing to protect them.

      The objective of this study is to assess what proportion of women achieve the desired anti Xa
      level with the fixed daily dose versus twice daily weight based dosing (0.5 mg/kg).
    

Eligibility criteria:

        Inclusion Criteria:

          -  Women with a body mass index >35 who have undergone cesarean delivery in the last 12
             hours who will receive thromboprophylaxis with enoxaparin

          -  Subjects who consent to the study.

        Exclusion Criteria:

          -  Women with a previous history of deep venous thrombosis or pulmonary embolism

          -  Women who are currently receiving another form of low molecular weight heparin or
             unfractionated heparin.

          -  Women who are receiving other concomitant anticoagulant medications, such as warfarin,
             lepirudin, or argatroban.

          -  Subjects who are unable or unwilling to give informed consent.

          -  Women who, in the judgment of the investigators, would not be in the best interest of
             the patient to participate in the study.

          -  Allergy to enoxaparin.

          -  Women with renal impairment

          -  Women with contraindications to Lovenox treatment such as women with active bleeding
             or thrombocytopenia