The Effect of Remifentanil on Rebound Pain

Study Overview
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Brief Summary
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The investigators will evaluate the influence of intraoperative remifentanil infusion on the postoperative hyperalgesia in patients receiving rotator cuff repair after brachial plexus block for postoperative analgesia.

Detailed Description
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The study will include 68 patients undergoing rotator cuff repair. All patients will receive brachial plexus block for postoperative analgesia, followed by general anesthesia. In the experimental group, remifentanil infusion will not be used intraoperatively, and in the control group, remifentanil will be infused. After surgery, both groups will be given the same postoperative pain management using patient controlled analgesia(PCA), and pain patterns will be assessed using the Numerical rating scale (NRS) at 4 hour intervals for 24 hours. The primary end point of this study is the total dose of PCA medication over 24 hours.

Official Title
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The Effect of Remifentanil on Rebound Pain in Patients Receiving General Anesthesia for Shoulder Arthroplasty After Brachial Plexus Block for Postoperative Pain Control

Conditions
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Pain, Postoperative

Intervention / Treatment
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* Drug: Not used remifentanil infusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA class I,II,III Patients undergoing arthroscopic rotator cuff repair surgery under general anesthesia after interscalen brachial plexus block for post operative analgesia Age ranges from 20 to 70 Exclusion Criteria: Patients who didn't agree to study Patients can't control PCA(Patient-Controlled-Analgesia) independently Patients who have conciousness disorder or can't express their pain level by NRS(Numeric Rating Scale) system Patients who have severe respiratory disease or hepatic failure Patinets who have known neuropathy or coagulopathy Pregnancy Patients with allegies to the drugs used in this study

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: not used intraoperative remifentanil infusion<br>Adult patients aged < 70 years and ASA class < III undergoing rotator cuff repair not used intraoperative remifentanil infusion | Drug: Not used remifentanil infusion<br>* Remifentanil is not used during operation<br>|
| No Intervention: used intraoperative remifentanil infusion<br>Adult patients aged < 70 years and ASA class < III undergoing rotator cuff repair used intraoperative remifentanil infusion maintaining target concentration of 2-6ng/ml | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total infused dose of patient controlled analgesia(PCA) drug during 24 hours | Total infused dose of patient controlled analgesia(PCA) drug during first 24 hours after rotor cuff repair under general anesthesia | From end of operation to the 24hours after operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Numerical Ratings Scale | Degree of pain is assessed using Numerical Ratings Scale at 4 hours for 24 hours after operation. The patients choose one of the digits from 0 to 10, the zero-point is painless, and the ten-point means the one with the most severe pain. | Pain levels are checked using Numerical Ratings Scale at 4 hour intervals for 24 hours after surgery | 
| Total patient's trial to PCA bolus infusion | The total number of times patients press the infusion button on the PCA to control pain | 24 hours after surgery | 
| Incidence of postoperative nausea and vomiting | Postoperative nausea and vomiting is assessed at 24hr after surgery by a face-to face interview | 24 hours after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hyperalgesia, brachial plexus block, remifentanil