Magnesium and Platelet Function Testing

Study Overview
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Brief Summary
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Magnesium has built up the reputation of a 'natural calcium antagonist'. However, the exact effect of magnesium on coagulation and more specifically on platelet function is still disputed. An important discrepancy between in vivo and in vitro studies exists. Magnesium has thus been reported to antagonize platelets in some studies, and to stimulate platelets in other studies. Current evidence seems to point in the direction of a general antagonization of aggregation and coagulation. Intravenous magnesium is often administered in pre-eclampsia as seizure prophylaxis. Therapeutic regimens usually consist of an intravenously administered loading dose (2-3 grams) and a maintenance infusion, targeting a plasma level of 2-3 mmol/L. Therapeutic drug monitoring is needed, as magnesium toxicity is an important concern.

Official Title
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Influence of Therapeutic Magnesium on Platelet Function Testing

Conditions
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Eclampsia Preeclampsia

Intervention / Treatment
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* Other: Collect a study-specific blood sample of healthy subjects


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Signed Informed consent Over 18 years of age (and younger or equal to 50 years of age) and able to provide legally binding consent American Society of Anesthesiologists physical fitness scale 1 (non smoker, no or minimal alcohol use, ..) Exclusion Criteria: Chronic disease Chronic medical therapy (other than oral contraception) Pregnancy ASA 2 or higher Known coagulation or aggregation disorders Use of COX-inhibitors in the last 10 days Contra-indications for venipuncture

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Control<br>Female Over 18 years of age American Society of Anesthesiologists physical fitness scale 1 Not pregnant | Other: Collect a study-specific blood sample of healthy subjects<br>* One heparin tube (4ml) and one hirudin tube (4ml) blood sample will be collected through standard venipuncture. After applying a tourniquet with moderate pressure around the arm of the patient's choice, skin will be disinfected over a suitable vein in the elbow or fore-arm. A hirudin and a heparin tube will be filled with venous blood through a single puncture with a 22 Ga needle (manufacturer, location). After release of the tourniquet, bleeding will be stopped by applying local pressure for 5 minutes with a sterile gauze.<br>* Other names: Collect an extra blood sample of pregnant woman during a routine control with an already planned blood sample collection;|
| Case<br>Female Pregnant with possible pre-eclampsia Over 18 years of age American Society of Anesthesiologists physical fitness scale 1 | Other: Collect a study-specific blood sample of healthy subjects<br>* One heparin tube (4ml) and one hirudin tube (4ml) blood sample will be collected through standard venipuncture. After applying a tourniquet with moderate pressure around the arm of the patient's choice, skin will be disinfected over a suitable vein in the elbow or fore-arm. A hirudin and a heparin tube will be filled with venous blood through a single puncture with a 22 Ga needle (manufacturer, location). After release of the tourniquet, bleeding will be stopped by applying local pressure for 5 minutes with a sterile gauze.<br>* Other names: Collect an extra blood sample of pregnant woman during a routine control with an already planned blood sample collection;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PAC-t-UB test results | The main endpoint of this study is the Platelet Activation Test in Unprocessed Blood (PAC-t-UB). | 4 months |