Role of Femoral Nerve Block on Prevention of Postoperative Deep Venous Thromboembolism

Study Overview
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Brief Summary
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To investigate whether preemptive analgesic of femoral nerve block could prevent deep venous thromboembolism due to inhibiting the excessive release of neutrophil elastase and inflammatory cytokines.

Detailed Description
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Femoral nerve block is an effective analgesic mode in patients after total knee arthroplasty. In recent studies, there has been shown that a large amount of neutrophil elastase release from neutrophils could induce the development of deep venous thromboembolism and femoral nerve block may reduce the incidence of the development of deep venous thromboembolism. In addition, inflammatory cytokines including interleukin-1(IL-1), IL-6, IL-8 and tumor necrosis factor(TNF) were associated with deep venous thromboembolism. Thus, the investigators hypothesised that preemptive analgesic of femoral nerve block could prevent deep venous thromboembolism due to inhibiting the excessive release of neutrophil elastase and inflammatory cytokines.

Official Title
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Prevention of Deep Venous Thromboembolism: Effect of Preemptive Analgesic of Femoral Nerve Block in Patients Undergoing Total Knee Arthroplasty

Conditions
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Gonarthrosis

Intervention / Treatment
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* Procedure: femoral nerve block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult patients scheduled for total knee arthroplasty under general anesthesia Exclusion Criteria: ASA physical status Ⅳ-Ⅴ, psychiatric illness, chronic opioid consumption, patient refusal, coagulopathy, peripheral neurological injury, local anesthesia drug allergy, preoperative existing deep venous thromboembolism.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: femoral nerve block<br>femoral nerve block will be administered before or after the surgery | Procedure: femoral nerve block<br>* use the nerve stimulator,the femoral nerve block will be administered before or after the surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum concentration of inflammatory cytokine |  | change from baseline at 30min, 60min, 90min after using tourniquet and 12h, 24h,48h after operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concentration of related inflammatory factors of deep venous thromboembolism | inflammatory factors include IL-1, IL-6, IL-8 and TNF，detecting the concentrations by enzyme-linked immunosorbent assay (ELISA). | change from baseline at 30min, 60min, 90min after using tourniquet and 12h, 24h,48h after operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Deep venous thromboembolism, Femoral nerve block, Total knee arthroplasty