The ED50 of DEX for Providing Sedation in Different Female Age Group

Phase 4

• Conditions: Combined Spinal-epidural Anesthesia
• Interventions: Drug: Dexmedetomidine B; Drug: Dexmedetomidine A; Drug: Dexmedetomidine C

• Registration Number: NCT02773017
• Lead Sponsor: Guangzhou General Hospital of Guangzhou Military Command

Brief Summary

Dexmedetomidine(DEX) could provide dose-dependent sedation , analgesia , anti-anxiety and inhibition of sympathetic nerves and other effects. Because of its minimal impact on the respiratory , currently it was more and more widely used to sedate patients undergoing regional anesthesia.Many anesthetic pharmacokinetics and pharmacodynamics are often affected by age, and current studies with regard to the effects of age on dexmedetomidine pharmacodynamic are rare. This study was designed to explore the right DEX dose of different female Age of patients to produce suitable sedation.Dexmedetomidine be used in patients with combined spinal and epidural anesthesia for sedation,which is monitored by the Narcotrend,during the operation.The relation between Narcotrend index (NTI) and the depth of sedation for patients is also investigated.

Detailed Description

90 patients scheduled for combined spinal epidural spinal anesthesia were included in one of three groups. In each group,determination of median effective (ED50) doses was performed by the Dixon up-and-down method, an initial dose of 1.0 μg/kg dexmedetomidine, with dose adjustment intervals of 0.1 μg/kg in first three turning points and 0.05μg/kg in the last three turning points.Initial doses was 1.4μg/kg, .Sedative efficacy was defined as an OAA/S of ≤3,30 min after the beginning of drug administration.

Study Timeline

• Study First Submitted: 2016-05-11
• Study First Submitted QC: 2016-05-11
• Study First Posted: 2016-05-16
• Status Verified: 2016-06
• Study Start: 2016-06
• Last Update Submitted: 2016-06-16
• Last Update Posted: 2016-06-17
• Primary Completion: 2016-09
• Study Completion: 2016-10

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: Female
• Target Recruitment: 90

Inclusion Criteria

1. ASA Ⅰ ~ Ⅱ patient undergoing lower extremity surgery
2. Written informed consent from the patient or the relatives of the participating patient.
3. BMI:18.0～25.0kg/m2

Exclusion Criteria

1. Mental illness can not match

2. epidural anesthesia contraindicated

3. People who have Slow-type arrhythmias

4. People who were language or hearing impaired

5. Sensory block reached to T8 or higher.

6. People who had lung infection or sleep apnea syndrome.

7. Pregnancy

8. Chronic renal failure

9. Alcohol or drug abuse

10. Already taking gabapentin, pregabalin, benzodiazepin or antidepression drug

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Middle-aged female group	Dexmedetomidine B	patients in the Middle-aged female group, aged 40\~60, were accepted an initial dose of 1.0 μg/kg dexmedetomidine, with dose adjustment intervals of 0.1μg/kg in first three turning points and 0.05μg/kg in the last three turning points.
Youth female group	Dexmedetomidine A	patients in the Youth female group, aged 20\~35, were accepted an initial dose of 1.0 μg/kg dexmedetomidine, with dose adjustment intervals of 0.1μg/kg in first three turning points and 0.05μg/kg in the last three turning points.
Elderly female group	Dexmedetomidine C	Patient in the elderly female group, aged 65\~79, were accepted an initial dose of 1.0 μg/kg dexmedetomidine, with dose adjustment intervals of 0.1μg/kg in first three turning points and 0.05μg/kg in the last three turning points.

Primary Outcome Measures

Name	Time	Method
The ED50 of DEX for providing sedation	30min after the start of the infusion	The aim of this study is to define the optimum bolus dose (ED50) of dexmedetomidine for producing adequate sedation during spinal anesthesia in different female age group using the Dixon and Mood up-and-down method。

Secondary Outcome Measures

Name	Time	Method
The ED95 of DEX	30min after the start of the infusion	To determine the optimum bolus dose (ED95) of dexmedetomidine for producing adequate sedation during spinal anesthesia in different female age group.

Trial Locations

Locations (1)

Guangzhou Military Region General Hospital, Department of Anesthesiology; 🇨🇳 Guangzhou, Guangdong, China