Multiple Electrode Aggregometry to Assess Platelet Function in Patients Undergoing Hip Joint Alloplasty With and Without Bone Cement

Study Overview
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Brief Summary
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The aim of the study is to assess blood platelet function and activation in patients undergoing both cement and non cement hip joint total alloplasty. Bone cement is used as a special biomaterial to help fix a hip prosthesis in place but is associated with bone cement implantation syndrome causing such complications as hypotension, cardiac arrhythmias. The pathophysiology of bone cement implantation syndrome is not fully known but one theory supports formation of clots in the bloodstream. This directly would activate platelets but no such study has been performed in humans. As bone reaming could potentially cause platelet activation even without bone cement, the study involves a control group of patients undergoing non cemented joint alloplasty.

Official Title
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Multiple Electrode Aggregometry to Assess Platelet Function in Patients Undergoing Hip Joint Alloplasty With and Without Bone Cement

Conditions
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Arthroplasty, Methylmethacrylate Embolism, Platelet Aggregation

Intervention / Treatment
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* Other: Blood sample 1
* Other: Blood sample 2


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients qualified for hip arthroplasty Signed consent for study No abnormality in coagulation screen Not taking regular antiplatelet medication except small dose of acetylsalicylic acid Exclusion Criteria: Lack of consent Low platelet count (<100 thousand) in standard preoperative full blood count On regular antiplatelet medication (except 75mg acetylsalicylic acid)

Ages Eligible for Study
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Minimum Age: 18 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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Hip arthroplasty with bone cement<br>Patients undergoing hip replacement surgery with bone cement use: blood samples taken before cement use and after cement prosthesis fixation. | Other: Blood sample 1<br>* Blood taken before prosthesis implantation<br>Other: Blood sample 2<br>* Blood taken after prosthesis implantation<br>|
| Non cement hip arthroplasty<br>Patients undergoing hip replacement surgery without bone cement. Blood samples taken before bone reaming and after implantation of femoral prosthesis. | Other: Blood sample 1<br>* Blood taken before prosthesis implantation<br>Other: Blood sample 2<br>* Blood taken after prosthesis implantation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in platelet aggregation as expressed by height and slope of curve | Differences in increase of impedance to a current during multiple electrode aggregometry measured as area under curve (AUC) expressed in units AU*minute which is derived from the velocity and maximum height of the aggregometry curves | Up to 30 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hip Joint Alloplasty, Bone Cements, Impedance Aggregometry, Platelet Activation