Efficacy of Dexmedetomidine on Postoperative Analgesia

Study Overview
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Brief Summary
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This prospective, randomized, double-blind study is designed to evaluate the postoperative analgesic efficacy of dexmedetomidine as an adjunct to ropivacaine in erector spinae block in patients undergoing radical mastectomy. The investigators hypothesis is that the administration of ropivacaine 0.5% associated with dexmedetomidine in the blockade via the plane in the erector spinae is less effective in controlling acute postoperative pain in radical mastectomy than the administration of ropivacaine 0.5% without dexmedetomidine.

Detailed Description
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Patients undergoing radical mastectomy are randomly assigned to receive, in addition to standard general anesthesia, a block of the erector spinae plane with ropivacaine at a dose of 0.5% for the control group (n = 13) and ropivacaine at a dose of 0.5% more dexmedetomidine at 0.3 mcg kg (n = 15) for the intervention group. General anesthesia was induced using anxiolysis with midazolam at 30 mcg / kg corrected weight, as induction, propofol at a dose of 1.5 - 2 mg kg, opioid analgesia with fentanyl at a dose of 3 mcg / kg weight corrected with 30% according to ideal weight initial bolus dose, and dose as required, neuromuscular relaxation with cisatracurium at a dose of 0.1 mg / kg.

Official Title
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Efficacy of Dexmedetomidine on Postoperative Analgesia After Radical Mastectomy: Randomized Controlled Trial

Conditions
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Postoperative Pain

Intervention / Treatment
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* Drug: Ropivacaine plus dexmedetomidine
* Drug: Ropivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing radical mastectomy for pathology breast cancer Patient undergoing anesthetic technique due to erector spinae plane block Informed consent to perform the anesthesia technique. Karnofsky> 80 points Exclusion Criteria: Emergency surgery Patient with mental pathology that prevents pain assessment. Rejection of anesthetic technique. Patient with allergy to local anesthetics Patient with local infection of the puncture site for application of the erector spinae 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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Female

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
Interventional Model Description: A prospective randomized double-blinded study
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ropivacaine plus Dexmedetomidine<br>In addition to standard general anesthesia, patients receive erector spinae block with ropivacaine at a dose of 0.5% plus dexmedetomidine at 0.3 mcg / kg corrected in a volume of 20 ml at the level of thoracic vertebra number 4, guided with ultrasound and under sterile technique, the date and time of application are recorded on the data collection sheet. | Drug: Ropivacaine plus dexmedetomidine<br>* Erector spinae block with ropivacaine at a dose of 0.5% plus dexmedetomidine at 0.3 mcg / kg.<br>|
| Active Comparator: Control group<br>In addition to standard general anesthesia, patients receive erector spinae block with ropivacaine at a dose of 0.5% in a volume of 20 ml at the level of thoracic vertebra number 4, guided with ultrasound and under sterile technique, the date and time of application are recorded on the data collection sheet. | Drug: Ropivacaine<br>* Erector spinae block with ropivacaine at a dose of 0.5%.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative Pain score | The intensity of pain is evaluated by the visual analog scale (VAS) that measures pain severity expressed on a numerical scale of 0-10: 0, no pain; 10, worst pain imaginable | 0 hours | 
| Postoperative Pain score | The intensity of pain is evaluated by the visual analog scale (VAS) that measures pain severity expressed on a numerical scale of 0-10: 0, no pain; 10, worst pain imaginable | 6 hours | 
| Postoperative Pain score | The intensity of pain is evaluated by the visual analog scale (VAS) that measures pain severity expressed on a numerical scale of 0-10: 0, no pain; 10, worst pain imaginable | 12 hours | 
| Postoperative Pain score | The intensity of pain is evaluated by the visual analog scale (VAS) that measures pain severity expressed on a numerical scale of 0-10: 0, no pain; 10, worst pain imaginable | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Additional opioid-type drugs | The presence of additional opioid analgesic requirements will be evaluated. All patients will be prescribed intravenous analgesia on a strict schedule as follows: ketorolac 30mg in intravenous infusion every 8 hours. If the follow-up assessment of postoperative pain is greater than or equal to 4 in the VAS, additional medication is indicated, which is considered as analgesic rescue and which consists of buprenorphine at a dose of 2 mcg kg corrected with 30% according to ideal weight intravenously in both groups, with a dose no greater than 6 mcg / kg / day. | 24 hours | 
| Postoperative nausea and vomiting | Incidence of postoperative nausea and vomiting (%) | 24 hours |