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

Central South University

Status and phase: Unknown; Phase 4

Conditions: Nodular Goiter

Treatments: Drug: Remifentanil

Study type: Interventional

Funder types: Other

Identifiers

NCT01761149

XYEYYCT2013001

Details and patient eligibility

About

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.

Full 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.

Enrollment: 60 estimated patients

Sex: All

Ages: 18 to 60 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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60 participants in 2 patient groups

Remifentanil (Low dose)

Active Comparator group

Description:

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

Treatment:

Drug: Remifentanil

Remifentanil (High dose)

Experimental group

Description:

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

Treatment:

Drug: Remifentanil