Ketamine in Robot-assisted Thyroidectomy

Study Overview
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Brief Summary
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In this prospective double-blinded study, The investigators compared acute postoperative pain and rescue analgesic demand during postoperative period after robot thyroidectomy between ketamine and placebo groups.

Detailed Description
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Robot-assisted endoscopic thyroidectomy has been popularized due to cosmetic advantages. Despite small incisions, robot thyroidectomy did not offer satisfactory reduction in postoperative pain compared to open thyroidectomy. Ketamine is a non-competitive N-methyl-D-aspartate (NMDA) receptor blocker and takes some attractive advantages in terms of pain control. When low dose ketamine is perioperatively administrated, opioid sparing effect during postoperative period is reported in various surgical procedures such as spine, thoracic, and gynecologic surgery. Ketamine's beneficial effect on postoperative pain has not been investigated in patients undergoing robot thyroidectomy. The investigators hypothesized that perioperative ketamine administration can reduce acute postoperative pain after robot thyroidectomy and the incidence of chronic pain hypoesthesia on anterior chest at 3 months after surgery.

Official Title
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The Efficacy of Intraoperative Ketamine in Patients Undergoing Robot-assisted Thyroidectomy

Conditions
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Thyroid, Acute Pain, Chronic Pain

Intervention / Treatment
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* Drug: Ketamine infusion
* Drug: NS infusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients scheduled for robot-assisted thyroidectomy ASA I-III Exclusion Criteria: Patients with renal dysfunction Patients with hepatic dysfunction Patients with neurologic dysfunction Patients with the history of drug addiction Patients with chronic pain Patients who are allergic to ketamine Patients with increased ocular or intracranial pressure Patients with the risk of aspiration

Ages Eligible for Study
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Minimum Age: 19 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 |
| --- | --- |
| Placebo Comparator: C group<br>In C group, NS infusion will be done intraoperatively. | Drug: NS infusion<br>* Normal saline will be infused intraoperatively.<br>|
| Experimental: KET group<br>In KET group, ketamine infusion will be done intraoperatively(0.25 mg/kg bolus injection following 100 mcg/kg/hr till the end of surgery). | Drug: Ketamine infusion<br>* Ketamine will be infused intraoperatively (0.25 mg/kg intravenous bolus following continuous infusion of 100 mcg/kg/hr).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain at 24 hour postoperatively | Pain at 24 hour postoperatively will be evaluates using 11 point scale (0:no pain, 10:worst imaginable) | at 24 hour postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain at 3, 6, 12, 48 and 72 hour postoperatively | Pain at 3, 6, 12, 48 and 72 hour postoperatively will be evaluated using 11-point scale 0:no pain, 10:worst imaginable) | at 3, 6, 12, 48 and 72 hour postoperatively | 
| Time to the first analgesics postoperatively | Time from the end of anesthesia till the first analgesic agent will be recorded at 24 hours postoperatively. | At 24 hours postoperatively | 
| Analgesic requirements for 24 hours after surgery | Analgesic requirements for 24 hours after surgery will be evaluated. | at 24 hours postoperatively | 
| Chronic pain at 3 month after surgery | Chronic pain at 3 month after surgery will be evaluated. | At 3 month after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Thyroidectomy, Endoscopy, Ketamine, Acute Pain, Chronic Pain, Postoperative period