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

Sponsor

Central South University (Other)

Overall Status

Unknown status

CT.gov ID

NCT01761149

Collaborator

(none)

Enrollment

Location

Arms

Study Details

Study Description

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.

Condition or Disease	Intervention/Treatment	Phase
Nodular Goiter	Drug: Remifentanil	Phase 4

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 Design

Study Type:

Interventional

Anticipated Enrollment :

60 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Double (Investigator, Outcomes Assessor)

Primary Purpose:

Treatment

Official Title:

Comparison of Different Doses of Remifentanil on Postoperative Pain in Patients Undergoing Thyroidectomy: a Prospective, Double-blinded Randomized Control Trial

Study Start Date :

Dec 1, 2012

Anticipated Primary Completion Date :

Mar 1, 2013

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: Remifentanil (Low dose) remifentanil(Low):dose of 0.2ug/kg/min. The dose of remifentanil is widely used intraoperatively clinically;	Drug: Remifentanil The present study examine two different dose of remifentanil: low dose (0.2ug/kg/min) and high dose (1.2ug/kg/min)
Experimental: Remifentanil (High dose) The high dose of remifentanil is 1.2ug/kg/min. The does is sometimes used in clinical practice.	Drug: Remifentanil The present study examine two different dose of remifentanil: low dose (0.2ug/kg/min) and high dose (1.2ug/kg/min)

Arm

Intervention/Treatment

Active Comparator: Remifentanil (Low dose)

remifentanil(Low):dose of 0.2ug/kg/min. The dose of remifentanil is widely used intraoperatively clinically;

Drug: Remifentanil

The present study examine two different dose of remifentanil: low dose (0.2ug/kg/min) and high dose (1.2ug/kg/min)

Experimental: Remifentanil (High dose)

The high dose of remifentanil is 1.2ug/kg/min. The does is sometimes used in clinical practice.

Drug: Remifentanil

The present study examine two different dose of remifentanil: low dose (0.2ug/kg/min) and high dose (1.2ug/kg/min)

Outcome Measures

Primary Outcome Measures

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

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.