Intramuscular Dexmedetomidine as Premedication

Study Overview
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Brief Summary
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Many studies have been conducted for the feasibility of using dexmedetomidine as premedication. However, bradycardia and hypotension frequently occurred following the premedication with dexmedetomidine, either via intramuscular or intravenous route. This is particularly true when using a high dose of dexmedetomidine: a intramuscular dose over 2 μg•kg-1 or a intravenous dose over 1 μg•kg-1 can elicit marked decreases in heart rate and mean arterial blood pressure. Subsequent studies using high-dose dexmedetomidine further revealed the potential impact of its detrimental haemodynamic profile on clinical outcomes. Most studies using high-dose dexmedetomidine were predominantly adopted with the dose-finding study performed by Aho and colleague, whom reported that 2.5 μg•kg-1 dose of intramuscular dexmedetomidine was comparably sedative and anxiolytic to 0.08 mg•kg-1 midazolam. However, few investigations have addressed the clinical effects of low-dose dexmedetomidine as premedication. Considering modern anaesthesia has advanced a long way towards eliminating the routine need for a deep preoperative sedation. It has, therefore, become desirable to asses dexmedetomidine as an effective premedication using a moderate sedative dose to minimize its undesired hemodynamic effects. We set a prospective study to compare the sedative, haemodynamic, adjuvant anaesthetic effects and patient's satisfaction of low-dose dexmedetomidine (1μg•kg-1) with midazolam (0.03 mg•kg-1), the most commonly used premedication, used as an intramuscular injective administration in patients undergoing suspension laryngoscopic surgery under general anaesthesia.

Official Title
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Comparison of Dexmedetomidine and Midazolam as Intramuscular Premedication for Suspension Laryngoscopy

Conditions
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Laryngoscopy, Preanesthetic Medication

Intervention / Treatment
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* Drug: Dexmedetomidine
* Drug: Midazolam


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients aged 18-55 years old, American Society of Anaesthesiologists physical status I, scheduled for elective suspension laryngoscopic surgery of benign vocal fold lesions. Exclusion Criteria: Patients with neurological deficits Pregnancy Imprisonment Morbid obesity (body mass index ≥ 30 kg•m-2) Preoperative heart rate <45 beats•min-1 Second or third degree atrioventricular block Antihypertensive medication with α-methyldopa, clonidine or other α2-adrenergic agonist

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dexmedetomidine<br>dexmedetomidine 1μg•kg-1 | Drug: Dexmedetomidine<br>* Dexmedetomidine<br>* Other names: Treatment;|
| Active Comparator: midazolam<br>midazolam 0.03 mg•kg-1 | Drug: Midazolam<br>* Midazolam<br>* Other names: control;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perioperative heart rate response |  | Participants will be monitored for the duration of anesthesia and recovery, an expected average of 2 hours. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sedation |  | Participants will be monitored for the duration of anesthesia and recovery, an expected average of 2 hours. | 
| Adjuvant anesthesia effect | Target-controlled infusion concentrations of propofol and remifentanyl at intubation, start and completion of surgery. | Participants will be monitored for the duration of anesthesia, an expected average of half an hour. | 
| Patient's over-all satisfaction | On discharge from recovery patients were asked to rate their satisfaction with the anaesthesia and the surgery that they had received as; highly satisfactory, acceptable, or unacceptable. | On leaving the post-care unite, an expected average of 2 min. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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dexmedetomidine, intramuscular premedication, bradycardiac