Effect of Adductor-Canal-Blockade on High Pain Responders After Total Knee Arthroplasty

Study Overview
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Brief Summary
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The purpose of this study is to determine whether Adductor-Canal-Blockade (ACB) is superior to placebo when it comes to analgetic efficacy in high pain responders after Total Knee Arthroplasty (TKA). High pain responders are defined as patients reporting VAS > 60 during knee flexion the 1. or 2. day after surgery.

Detailed Description
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The patients will be included the 1. or 2. day after surgery. All TKA patients will be screened. Those reporting VAS > 60 during active 45 degrees knee flexion will be asked to participate. Included patients will receive 2xACB (singleshot) first placebo (30ml saline) and then ropivacaine (30ml ropivacaine 7,5mg/ml) or the other way around (randomized). There will be 45 minutes between the two blockades. The blockades will be ultrasound guided.

Official Title
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Effect of Adductor-Canal-Blockade on High Pain Responders the 1. or 2. Postoperative Day After Total Knee Arthroplasty

Conditions
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Pain After Total Knee Arthroplasty

Intervention / Treatment
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* Drug: Ropivacaine
* Drug: Saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: TKA within 48 hours and VAS>60 during active 45 degrees knee flexion despite conventional pain medication. Informed consent ASA 1-3 BMI 18-40 Exclusion Criteria: Unable to communicate in Danish Allergic reactions toward drugs used in the Abuse of alcohol/drugs Unable to cooperate

Ages Eligible for Study
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Minimum Age: 30 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Arm RP<br>first blockade: ropivacaine 7,5mg/ml 30 ml second blockade: placebo: saline 30 ml | Drug: Ropivacaine<br>* Arm RP is receiving 30 ml of ropivacaine 7,5 mg/ml at first blockade (ACB) and after 45 minutes another blockade (ACB) with placebo (saline 30 ml). Arm PR is receiving 30 ml of placebo (saline) at first blockade (ACB) and after 45 minutes another blockade (ACB)with ropivacaine.<br>* Other names: Naropin;Drug: Saline<br>* please see intervention description for ropivacaine<br>* Other names: NaCl, placebo;|
| Other: Arm PR<br>first blockade: placebo: saline 30 ml second blockade: ropivacaine 7,5mg/ml 30 ml | Drug: Ropivacaine<br>* Arm RP is receiving 30 ml of ropivacaine 7,5 mg/ml at first blockade (ACB) and after 45 minutes another blockade (ACB) with placebo (saline 30 ml). Arm PR is receiving 30 ml of placebo (saline) at first blockade (ACB) and after 45 minutes another blockade (ACB)with ropivacaine.<br>* Other names: Naropin;Drug: Saline<br>* please see intervention description for ropivacaine<br>* Other names: NaCl, placebo;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in VAS between ACB and placebo during active 45 degrees knee flexion |  | 45 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in mean VAS between the groups during active knee flexion |  | 15, 30, 60, 75 and 90 minutes | 
| Difference in mean VAS between the groups at rest |  | 15, 30, 60, 75 and 90 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Total knee arthroplasty, Adductor canal blockade (ACB), High pain responders, US-guided nerve block