Dexmedetomidine to Prevent Agitation After Free Flap Surgery

Study Overview
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Brief Summary
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Reconstruction using microvascular free tissue flap has been an important management in patients with maxillofacial tumor. It is often characterised as long operation time, more traumatic and require restriction of patient's head movement postoperatively in order to prevent disruption of microvascular anastomosis. Agitation and delirium are common in patients with free flap surgery, which may lead to serious consequences such as self extubation, injury or even failure of the flap. Dexmedetomidine is a sedative and co-analgesic drug with high specificity for α2-adrenoceptor. It is widely used in ICU sedation in general hospital. However its use after free flap surgery is not well documented. Furthermore the effect of Dexmedetomidine on preventing delirium has not been proved. The investigators hypothesized that the use of Dexmedetomidine would reduce emergence agitation and prevent delirium in patients after free flap surgery.

Official Title
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The Effect of Dexmedetomidine on Agitation and Delirium in Patients After Free Flap Reconstructive Surgery

Conditions
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Agitation, Delirium

Intervention / Treatment
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* Drug: Dexmedetomidine
* Drug: Saline placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing selected maxillofacial surgery with free flap reconstruction American Society of Anesthesiologist(ASA) classification I and II Exclusion Criteria: bradycardia (< 50 bpm) severe heart block low blood pressure(SBP<80mmHg) Known allergy to alpha 2 agonists

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: dexmedetomidine<br>Dexmedetomidine(4㎍/mL) : 0.5㎍/kg/hr infusion for 1 hour before operation is completed and 0.2-0.7㎍/kg/hr infusion continuously until 6:00am the next day. | Drug: Dexmedetomidine<br>* Dexmedetomidine(4㎍/mL) : 0.5㎍/kg/hr infusion for 1 hour before operation is completed and 0.2-0.7㎍/kg/hr infusion continuously until 6:00am the next day.<br>* Other names: Precedex;|
| Placebo Comparator: control<br>Drug: Normal saline 0.9% (guess as 4㎍/mL) : 0.5㎍/kg/hr infusion for 1 hour before operation is completed and 0.2-0.7㎍/kg/hr infusion continuously until 6:00am the next day. | Drug: Saline placebo<br>* Normal saline 0.9% (guess as 4㎍/mL) : 0.5㎍/kg/hr infusion for 1 hour before operation is completed and 0.2-0.7㎍/kg/hr infusion continuously until 6:00am the next day<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Agitation in PACU | Patients are kept calm and cooperative in the PACU. Agitation is defined as Riker-Agitation Scale(SAS)>=5. | participants will be followed for the duration of PACU stay, an expected average of 12 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative Delirium | Patients are sent back to wards the next morning after operation and followed up on each of the 5 days postoperatively. Delirium will be confirmed based on CAM-ICU method. | on each of the 5 days postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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agitation, delirium, dexmedetomidine, head and neck surgery, microvascular free tissue transfer, flap