Selective Block of the Axillary Nerve in Postoperative Pain Management

Study Overview
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Brief Summary
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In this study the investigators wish to compare the effect of a selective axillary nerve block to placebo in patients undergoing arthroscopic shoulder surgery. It is the investigators hypothesis that the amount of morphine consumption in the first 4 hours postoperatively in the intervention group will be significant lower than in the placebo group.

Official Title
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Selective Block of the Axillary Nerve in Postoperative Pain Management, a Randomised, Blinded, Placebo-controlled Trial

Conditions
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Pain, Postoperative

Intervention / Treatment
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* Drug: ropivacaine
* Drug: Sodium chloride


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects undergoing arthroscopic shoulder surgery Age between 18 and 80 years ASA 1-3 BMI between 18 and 35 kg/m2 Subjects which have given their written informed consent Exclusion Criteria: Subjects unable to cooperate to the investigation Subjects not understanding or speaking danish Subjects allergic to intervention drugs Daily use of strong analgesics (morphine, oxycontine, ketogan) Alcohol or medicine misuse Failure of nerve block

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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 |
| --- | --- |
| Placebo Comparator: Placebo<br>Sodium chloride | Drug: Sodium chloride<br>* Single shot nerve block with isotonic sodiumchloride 10-20 ml; 0.9%<br>|
| Active Comparator: ropivacaine<br>Naropin | Drug: ropivacaine<br>* Single shot nerve block with ropivacaine 10-20 ml; 7,5 mg/ml<br>* Other names: Naropin;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Morphine consumption | Patients are coupled to an intravenous PCA pump. The amount of morphine administered by the patient in the first 4 hours postoperatively is registered. | 0-4 hours postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual analogue scale (VAS) score | Postoperative VAS scores during the first 24 hours postoperatively, divided into two periods. | 0-12 hours and 12-24 hours postoperatively | 
| Total morphine consumption | The total amount of morphine administered during the first 24 hours postoperatively | 0-24 hours postoperatively | 
| Postoperative nausea and vomiting (PONV) | Postoperative nausea evaluated on a 1-3 scale with and without vomiting | 0-4, 0-12 and 12-24 hours postoperatively | 
| Escape block | The use of an escape block (interscalene brachial plexus block) in patients with pain breakthrough despite IV morphine 0-4 hours postoperatively. | 0-4 hours postoperatively | 
| Bolus morphine 5 mg iv | Number of morphine boli administered during the first 4 hours postoperatively | 0-4 hours postoperatively |