The Effect of Ultra-low-dose Naloxone on Remifentanil-induced Postoperative Hyperalgesia - A Randomized Controlled Study

Not Applicable

Completed

• Conditions: Pain
• Interventions: Drug: Low dose remifentanil; Drug: High dose Remifentanil; Drug: Normal Saline; Drug: Naloxone

• Registration Number: NCT02856087
• Lead Sponsor: Seoul National University Hospital

Brief Summary

High-dose remifentanil infused intraoperative ironically results in postoperative hyperalgesia. Ultra-low dose nalxone is demonstrated to prevent these opioid-induced hyperalgesia in animal model. In this clinical trial in patients undergoing general anesthesia with remifentanil, we evaluate the effects of ultra-low-dose naloxone on remifentanil-induced hyperalgesia

Detailed Description

We enrolled adult patients undergoing thyroidectomy under general anesthesia with desflurane and remifentanil. Remifentanil was administered via target-controlled infusion and anesthetic depth was maintained keeping the BIS between 40 and 60. Patients were randomized into one of three groups depending on intraoperative doses of remifentanil and naloxone: effect-site concentrations of remifentanil 1 ng/ml (control group), 4 ng/ml (remifentanil group), and 4 ng/ml combined with infusion rate 0.8 ng/kg/min of naloxone (remifentanil and naloxone group). Postoperative mechanical pain thresholds, pain intensity, and analgesic consumption were examined during 48 h of postoperative period. The primary outcome was mechanical pain threshold measured on the peri-incisional area 24 h after surgery.

Study Timeline

• Study Start: 2014-11
• Primary Completion: 2015-04
• Study Completion: 2015-04
• Study First Submitted: 2016-08-02
• Study First Submitted QC: 2016-08-02
• Study First Posted: 2016-08-04
• Status Verified: 2016-11
• Last Update Submitted: 2016-11-15
• Last Update Posted: 2016-11-16

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 92

Inclusion Criteria

• patients who are scheduled to undergo elective thyroidectomy

Exclusion Criteria

• consent refusal, obesity, pregnancy, hx. of thyroid surgery, neurological disorders, psychiatric disorders, hx. of drug abuse or chronic use of opioids or sedative drugs, intake of any analgesic drug within 12h before surgery.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
group LR	Low dose remifentanil	low dose remifentanil (1 ng/ml of Ce) with normal saline infusion
group HR-N	High dose Remifentanil	remifentanil infusion at 4ng/ml of Ce with naloxone infusion
group LR	Normal Saline	low dose remifentanil (1 ng/ml of Ce) with normal saline infusion
group HR	High dose Remifentanil	High dose remifentanil infusion (4ng/ml of Ce) with normal saline infusion
group HR	Normal Saline	High dose remifentanil infusion (4ng/ml of Ce) with normal saline infusion
group HR-N	Naloxone	remifentanil infusion at 4ng/ml of Ce with naloxone infusion

Primary Outcome Measures

Name	Time	Method
Mechanical pain thresholds	24hr after surgery	Mechanical pain thresholds were assessed by von Frey filaments. The patients were asked to close their eyes during the test, and an investigator made the filament pressing the skin perpendicularly against the skin until bowing and being maintained for 1.5 seconds. The filament size was started from 0.4 g and was increased to the point until the patient perceives a clear change in sensation.

Secondary Outcome Measures

Name	Time	Method
Mechanical pain thresholds	48hr after surgery
pain score	verbal numerical rating scale at 48 after surgery

Trial Locations

Locations (1)

Seoul National University Hospital; 🇰🇷 Seoul, Korea, Republic of