Hip-Fracture Surgery on Patients in Clopidogrel Therapy

Study Overview
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Brief Summary
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Patients in Clopidogrel therapy alone or in combination with acetylsalicylic acid (Dual Antiplatelet Therapy (DAPT) presenting with a hip-fracture represent the surgeon with the dilemma of putting the patient at risk of a major blood loss during and after surgery, or putting the patient at risk of a thromboembolic event after surgery. The investigators hypothesize that the risk of a major blood loss in patients that are still under the effect of Clopidogrel or DAPT during or after hip-fracture surgery is relatively low. The investigators have conducted a retrospective observational study on hip-fracture patients to test this hypothesis.

Conditions
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Hip Fracture

Intervention / Treatment
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* Drug: Clopidogrel


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients operated with short intramedullary nail for hip-fractures, in the study period. (1st of Jan. 2011-31st of Dec. 2013) Exclusion Criteria: patients operated >24 hours after admission, patients in other forms of anticoagulation medication except acetylsalicylic acid (including vitamin K antagonists, dipyridamole, dabigatran, apixaban and rivaroxaban), missing data on blood loss in patient chart, missing blood samples in the first 4 days and extra-national patients (follow up not possible). Patients operated on both sides during the inclusion period were only included with data on their latest operation.
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 |
| --- | --- |
| Clopidogrel<br>Patients in Clopidogrel or Dual Antiplatelet Therapy (Clopidogrel+Acetylsalicylic acid) at the time of admission AND who are operated <24 hours after admission. | Drug: Clopidogrel<br> <br> |
| Control<br>Patients NOT in anticoagulation treatment (Except acetylsalicylic acid) AND who are operated <24 hours after admission. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surgical Blood Loss | Blood loss as assessed by the surgeon | at time of surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total BLood Loss | Calculated based on the method described by Foss et al 2006 (Hidden Blood Loss in hip fractures) | From admission to third day after surgery. | 
| Number of transfusions | Number of Red Blood Cell transfusions | From admission to third day after surgery | 
| 30 and 90 day mortality | Recorded from national persons registry (CPR-registeret) | 30 and 90 days postoperatively | 
| Massive transfusion | >10 Red Blood Cell transfusion within 24 hours of surgery. | within 24 hours of surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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clopidogrel therapy, platelet aggregation inhibitor, adverse event