Comparing Anti-XA Levels in Post-Cesarean Patients Undergoing Enoxaparin Thromboprophylaxis

• Status: Completed
• Trial end date: 2014-03-01
• Target enrollment: 0
• Participant gender: Female

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).

• Phase: Phase 1
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: MemorialCare Health System
• Treatments: Enoxaparin

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