Venous Thromboprophylaxis in Bariatric Surgery

Study Overview
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Brief Summary
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The main aim of this study is to compare the influence of total body-weight (TBW), lean body-weight (LBW), ideal body-weight (IBW) or Body Mass Index (BMI) on peak anti-Xa levels at steady-state in bariatric surgery (BS) morbidly obese patients receiving a fixed double dose of dalteparin (5000 IU subcutaneously, twice daily a day) for venous thromboembolism (VTE) prevention. Secondary aims of this study are to identify which body size descriptors (BSD) has the greatest impact and could further be explored for an adjusted low molecular weight heparin (LMWH) dosing algorithm for achieving optimal VTE prevention in BS severely obese patients.

Detailed Description
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Severely obese patients undergoing bariatric surgery (BS) are at increased risk for venous thromboembolism (VTE). How standard LMWH regimen should be adapted to provide both sufficient efficacy and safety in this setting is unclear. The aim of this study is to compare the influence of four BSD on peak anti-Xa levels in BS obese patients receiving high LMWH fixed doses to identify which one had the greatest impact and could further be proposed in LMWH-based thromboprophylaxis dosing algorithms.

Official Title
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Evaluating Body Size Descriptors on Peak Anti-Xa Levels in Bariatric Surgery Obese Patients Receiving Low Molecular Weight Heparin Fixed Doses

Conditions
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Obesity

Intervention / Treatment
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* Drug: Dalteparin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: between 18 and 70 years old BMI ≥ 40 Kg/m² or BMI ≥ 35 Kg/m² with at least one or more obesity-related co-morbidities ( including type II diabetes (T2DM), hypertension, obstructive sleep apnea (OSA), non-alcoholic fatty liver disease, severe osteoarthritis, lipid abnormalities, gastrointestinal disorders, or heart disease) scheduled for sleeve gastrectomy (SG) or gastric bypass procedure (GBP) informed consent Exclusion Criteria: anticoagulant administration within 48 hours preceding surgery on-going antiplatelet therapy pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: Dalteparin|nan|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of patients whose peak plasma anti-Xa levels is in the prophylactic ranges | Proportion of patients whose peak plasma anti-Xa levels is in the prophylactic ranges.The target range for prophylactic anti-Xa levels is defined as 0.2 to 0.5 IU/ml | at least two days after thromboprophylaxis initiation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of patients with symptomatic VTE | Proportion of patients with symptomatic VTE | 3 months | 
| Proportion of patients with major bleeding | Proportion of patients with major bleeding | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Obesity, Venous thromboembolism, Heparin, Low-Molecular-Weight, Body Composition, Glomerular filtration rate, Bariatric Surgery