Dexmedetomidine for Prevention of Chronic Postoperative Pain

Study Overview
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Brief Summary
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Chronic postoperative pain (CPSP) is common symptom in patients after surgery, seriously affected the quality of life. Accumulating evidences have demonstrated dexmedetomidine can improve chronic pain. However, the prevention of dexmedetomidine on CPSP remain uncertain.

Detailed Description
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Chronic postoperative pain (CPSP) is defined as pain persisting at least 3 months after surgery. It is most common in patients who undergoing breast or thoracic surgery. Dexmedetomidine, a adrenergic α2 agonists, can alleviate the postoperative pain 24 h after surgery. In our study, patients were randomly assigned to one of the two group to receive 0.5mg/kg/h infusion dexmedetomidine (Group D, n=57) or normal saline (Group C, n=57). The pain scales were evaluated day 1, day 2, day 3, month 3, month 6 after surgery.

Official Title
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a Randomized Controlled Trial of Dexmedetomidine on Chronic Postoperative Pain After Breast and Thoracic Surgery

Conditions
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Chronic Postoperative Pain

Intervention / Treatment
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* Drug: saline
* Drug: dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients must have been 18 to 65 yr old, and been scheduled for breast or thoracic surgery. Exclusion Criteria: Patients with limitations of self-expression or visual dysfunction or having emergency surgery, a severe psychiatric illness, or chronic pain problems in the chest area for longer than 2 months before the surgery,or patients who could not provide informed consent were excluded. Pregnant women and prisoners were also excluded.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: paitents undergoing breast or thoracic surgery
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: control group<br>an equal volume of saline | Drug: saline<br>* an equal volume of saline<br>|
| Experimental: dexmedetomidine<br>dexmedetomidine, 0.5ug/kg/h by intravenous infusion, intraoperative | Drug: dexmedetomidine<br>* dexmedetomidine, 0.5ug/kg/h by intravenous infusion, intraoperative<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the pain intensity measure | Self reported pain intensity in rest and activity will be recorded at day 1 before sugery, month 3, month 6, month 12 after sugery. The intensity of pain was measured by numeric rating scale (0=no pain, 10=worst possible pain) | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| anxiety | The anxiety will be self reported by patents at day 1 before surgery, month 3, month 6, month 12 after surgery.The anxiety will be scored by a Visual Analogue Scale of anxiety (0=no anxiety, 10=worst possible anxiety) | 12 months | 
| depression | The depression will be evaluated at day 1 before surgery, month 3, month 6, month 12 after sugery by a questionnaire | 12 months | 
| sleep disturbance | Sleep disturbance will be evaluated at day 1 before surgery, month 3, month 6, month 12 after sugery by questionnaires. | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Chronic pain, CPSP, Dexmedetomidine, Surgery