Effect of Dexmedetomidine for Postoperative Intravenous Patient Controlled Analgesia

Study Overview
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Brief Summary
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The purpose of this study is to explore the effectiveness of dexmedetomidine as an adjunctive analgesic, combined with dezocine and flubiprofen, used in intravenous Patient-Controlled Analgesia (PCA) after open colorectal surgery.

Detailed Description
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Dexmedetomidine is a selective alpha-2 adrenoceptor agonist, which has been demonstrated to have anaesthetic, sedative and analgesic-sparing effects. Besides, Dexmedetomidine has been reported to cause sedative effects and reduce opioid requirements in the perioperative period. Many studies had been conducted to reduce the side effect of opioid analgesic. The current trend of reducing opioid analgesic side effect is direct combination of other drugs in PCA. The advantages of this method are convenient in clinical use and preventive for side effects. In this study, 50 patients who is undergoing elective colorectal surgery will be randomly allocated into two groups (Control group and Dexmedetomidine group). Patients in both groups will be given a patient-controlled analgesia (PCA) pump in post anesthetic recovery unit (PACU) after surgery. The PCA protocol of Control group is dezocine 0.6mg/kg, flubiprofen 3mg/kg, diluted into 120ml and administer at a background infusion of 2ml/h, and a bolus of 2ml, with a lock-out of 15min. The PCA protocol of Dexmedetomidine group is dezocine 0.6mg/kg, flubiprofen 3mg/k and dexmedetomidine 6μg/kg diluted into 120ml and administer at a background infusion of 2ml/h, and a bolus of 2ml, with a lock-out of 15min.

Official Title
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Effect of Dexmedetomidine Combined With Dezocine and Flubiprofen for Postoperative Intravenous Patient Controlled Analgesia After Colorectal Surgery

Conditions
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Patient-Controlled Analgesia

Intervention / Treatment
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* Drug: Dezocine
* Drug: Flubiprofen
* Drug: Dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologists(ASA) Ⅰ-Ⅱ patient undergoing open colorectal surgery Written informed consent from the patient or the relatives of the participating patient. BMI:18～30kg/m2 Exclusion Criteria: Mental illness or cannot communicate.; A second operation during the study; Slow-type arrhythmias or hypotension; Lung infection or sleep apnea syndrome; Renal failure; Alcohol or drug abuse; Already taking gabapentin, pregabalin, benzodiazepin or antidepression drug; Long-term use of analgesics,sedatives or non steroidal anti-inflammatory drugs history;

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: Health Services Research
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control Group<br>Patients in this group receive intravenous Patient-Controlled Analgesia(PCA) pump after surgery.The intravenous PCA protocol is dezocine 0.01mg/kg/h,flubiprofen 0.05mg/kg/h. | Drug: Dezocine<br>* Dezocine 0.01mg/kg/h intravenous administration during the first two days after surgery.<br>Drug: Flubiprofen<br>* Flubiprofen 0.5mg/kg/h intravenous administration during the first two days after surgery.<br>|
| Experimental: Dexmedetomidine Group<br>Patients in this group receive intravenous Patient-Controlled Analgesia(PCA) pump after surgery.The intravenous PCA protocol is dezocine 0.01mg/kg/h,flubiprofen 0.05mg/kg/h,dexmedetomidine 0.1μg/kg/h. | Drug: Dezocine<br>* Dezocine 0.01mg/kg/h intravenous administration during the first two days after surgery.<br>Drug: Flubiprofen<br>* Flubiprofen 0.5mg/kg/h intravenous administration during the first two days after surgery.<br>Drug: Dexmedetomidine<br>* Dexmedetomidine 0.1μg/kg/h intravenous administration during the first two days after surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dezocine consumption by patient-controlled analgesia | The total consumption of dezocine during 24 hours after surgery are recorded. | At 24 hours after surgery | 
| Change in pain score | Pain scores at rest and movement are evaluated with a numeric rating scale (NRS). | At 0, 2, 4, 8, 24, 48 and 72 hours after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in ramsay sedation score | Measure sedation level by using ramsay sedation score | At 0, 2, 4, 8, 24, 48 and 72 hours after surgery | 
| The incidence rates of postoperative nausea and vomiting (PONV) | Measure whether nausea and vomiting exist and the level of severity. | At 24 hours after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Dexmedetomidine, Dezocine, Flubiprofen, Analgesia, Colorectal Surgery