Sedation With Dexmedetomidine Versus Remifentanil in Urogynecological Surgery Under Spinal Anaesthesia

Study Overview
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Brief Summary
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Neuraxial blocks are usually used as an anaesthetic method for urogynecological surgeries. In most patients under regional anaesthesia, premedication is given for reducing anxiety. Purpose of this prospective double blind randomised clinical trial is the investigation of the effect of perioperative intravenous infusion of dexmedetomidine vs remifentanil for sedation in patients under spinal anaesthesia for urogynecological procedures.

Detailed Description
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The day before surgery the procedure will be explained to the patient and the written consent will be obtained. In the operating room, intraoperative monitoring will include ECG, noninvasive blood pressure, oxygen saturation by pulse oximetry (SpO2) and heart rate (HR). A peripheral intravenous catheter wil be placed for fluid replacement ( Ringer's Lactate solution 6 - 8ml/ kg/hr) and administration of drugs. Women will be randomly assigned into one of two groups: Group A: Women will receive dexmedetomidine continuously infused at a dose of 0,6 mcg/kg for 10 minutes (concentration of the solution 6mcg/ml) before spinal anaesthesia. Infusion will be stopped in order to proceed with regional anesthesia. Group B: Women will receive remifentanil continuously infused at a dose of 1mcg/kg for 10 minutes (concentration of the solution 1mcg/ml) before spinal anaesthesia. Infusion will be stopped in order to proceed with regional anesthesia. The insertion of a 27 Gauge (27G) spinal needle is performed at L3-L4 or L4-L5 interspace, in the lateral position. All patients will receive 2,7 ml ropivacaine 0,75% and 15 mcg fentanyl intrathecally and assessment of sensory and motor block will be assessed every 2 min. The moment that sensory block is in the highest dermatome and motor block is complete (Bromage grade 3) is Time to max effect (Tmax). In group A an infusion of dexmedetomidine (6mcg/ml) at a dose of 0,6mcg/kg/hr will be administered and in group B an infusion of remifentanil (1mcg/ml) at a dose of 0,03 mcg/kg/min.At the end of the surgery patients will be transferred in Post Anaesthetic Care Unit (PACU) and a patient control analgesia (PCA) pump will be provided to the patient, administering 1 mg of morphine in every attempt, with a lock out interval of 10 minutes.There will be no continuous infusion. All patients will receive a standardized multimodal approach, including diclofenac 50 mg t.i.d, paracetamol 1gr as rescue analgesia (max 4 gr per day) and PCA with morphine.

Official Title
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Sedation With Dexmedetomidine Versus Remifentanil in Urogynecological Surgery Under Spinal Anaesthesia : Impact on Block Characteristics, on Acute and Chronic Postoperative Pain

Conditions
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Vaginal Hysterectomy, Suburethral Slings

Intervention / Treatment
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* Drug: Dexmedetomidine
* Drug: Remifentanil


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Physical status according to American Society of Anesthesiologists (ASA) I-II Patients scheduled for transvaginal urogynecological or gynecological surgery Exclusion Criteria: Patient refusal Contraindication of spinal anaesthesia (Coagulopathy, Local infection at the site of injection, Local anaesthetic allergy, Hypovolaemia) BMI > 30 kg/m2 Personal history of cardiovascular disease Arrythmias Conduction disorders Severe kidney or liver dysfunction Insulin-dependent diabetes mellitus Central nervous system disorders Psychiatric and mental status disorders Chronic Excessive Alcohol Consumption Chronic Use of Opioid Analgesics Chronic Use of corticosteroids Chronic Use of clonidine (or other a2 adrenergic agonist) Use of drugs acting on central nervous system or analgetics the last two weeks Communication problems due to language barriers or unable to understand the pain scale

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 75 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
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Group DEX<br>Intravenous administration of dexmedetomidine 0.6 mcg / kg within 10 minutes prior to regional anesthesia. The infusion of the solution will be discontinued and then will be performed in all patients subarachnoid anesthesia. Starting with Tmax, infusion of the solution will be initiated again at a dose of 0.6 mcg / kg / h. | Drug: Dexmedetomidine<br>* Intravenous administration of dexmedetomidine 0.6 mcg / kg within 10 minutes prior to regional anesthesia and 0.6 mcg / kg / h after performing regional anaesthesia until the end of the surgery<br>* Other names: DEXDOR;|
| Active Comparator: Group REMI<br>Intravenous administration of remifentanil 1 mcg / kg within 10 minutes prior to regional anesthesia. The infusion of the solution will be discontinued and then will be performed in all patients subarachnoid anesthesia. Starting with Tmax, infusion of the solution will be initiated again at a dose of 0.025 mcg / kg / min. | Drug: Remifentanil<br>* Intravenous administration of remifentanil 1 mcg / kg within 10 minutes prior to regional anesthesia and 0.025 mcg / kg / h after performing regional anaesthesia until the end of the surgery<br>* Other names: ULTIVA;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration of postoperative analgesia | Time for first analgesia / PCA first bolus | 24 hours postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Analgesic consumption | Morphine consumption in mg | 0 hours, 2 hours, 4 hours, 8 hours, 24 hours postoperatively |