Effect of Higher Doses of Remifentanil on Postoperative Pain in Patients Undergoing Thyroidectomy

Phase 4

• Conditions: Nodular Goiter
• Interventions: Drug: Remifentanil

• Registration Number: NCT01761149
• Lead Sponsor: Central South University

Brief Summary

Extensive clinical studies have shown that intraoperative infusion high dose of remifentanil (0.2ug/kg/min) induced postoperative hyperalgesia. Recent experimental study however suggests that higher dose of remifentanil may attenuate postoperative hyperalgesia. Thus, the present study is designed as a "proof of principle" study and hypothesizes that higher dose of remifentanil may reduce postoperative pain in patients.

Detailed Description

Remifentanil, an ultra-short acting opioid, is widely used in the patients undergoing surgery. However, extensive studies report that remifentanil,administered at 0.2ug/kg/min or 0.4ug/kg/min intraoperatively, can result in postoperative hyperalgesia and increase the consumption of analgesics when compared with low dose (0.05ug/kg/min). However, a recent experimental study shows that large dose of remifentanil can inhibit pain hypersensitivity through erasing the spinal sensitization of pain. The present study thus hypothesizes that higher dose of remifentanil (1.2ug/kg/min) may attenuate postoperative pain. The present study will compare the effect of two different dose of remifentanil (0.2ug/kg/min and 1.2ug/kg/min) on postoperative pain. Patients undergoing thyroidectomy will be recruited, and mechanical threshold will be measured in the remote region of surgical site preoperatively. The patients will be randomly divided by two groups, 0.2ug/kg/min (group I) and 1.2ug/kg/min (group II). After operation, mechanical threshold and visual analogue scale (VAS) will be measured as the indicators of postoperative pain. The consumption of morphine will also be compared between these two doses of remifentanil.

The present study may find optimized dose of opioid usage in the patients undergoing surgery to relieve the postoperative pain.

Study Timeline

• Study Start: 2012-12
• Study First Submitted: 2012-12-30
• Status Verified: 2013-01
• Study First Submitted QC: 2013-01-03
• Last Update Submitted: 2013-01-03
• Study First Posted: 2013-01-04
• Last Update Posted: 2013-01-04
• Primary Completion: 2013-03

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

• ASA Grade I or II
• Age 18-60 years old
• BMI<35,

Exclusion Criteria

• do not consent,
• Chronic pain,
• used pain killer,
• undergoing operation previously
• diabetes or the other diseases affecting the sensory.
• difficult intubation;
• unexpected surgical complication such as bleeding;
• psychiatric disorders;
• drug or alchohol abuse

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Remifentanil (High dose)	Remifentanil	The high dose of remifentanil is 1.2ug/kg/min. The does is sometimes used in clinical practice.
Remifentanil (Low dose)	Remifentanil	remifentanil(Low):dose of 0.2ug/kg/min. The dose of remifentanil is widely used intraoperatively clinically;

Primary Outcome Measures

Name	Time	Method
Changes of sensory threshold from baseline to postoperative 24hours	24 hour	Quantitative sensory threshold in the remote uninjured site (here, the inner forearm) is commonly used to examine the occurrence of postoperative hyperalgesia. The present study will examine the mechanical threshold in two different doses of remifentanil to determine whether high dose of remifentanil induces hyperalgesia

Secondary Outcome Measures

Name	Time	Method
visual analogue score (VAS)	24 hours	VAS is widely used to assess postoperative pain. It will be divided as 10 points. Zero refers to no pain and ten refers to extremely pain. Based on this way, we can know the difference of postoperative pain in these two different groups.

Trial Locations

Locations (1)

Department of Anesthesiology, The Second Xiangya Hospital; 🇨🇳 Changsha, Hunan, China