Clinical trial NCT02099253: The Influence of Age on Dexmedetomidine Pharmacodynamic
Official title: The Influence of Age on Dexmedetomidine Pharmacodynamic in Lower Extremity Surgery
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Spinal Anesthesia
Keywords: Age
Pharmacodynamics
dexmedetomidine
Lead sponsor: Guangzhou General Hospital of Guangzhou Military Command
Sponsor class: OTHER
First posted: 2014-03-28
Enrollment: 82
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Dexmedetomidine(DEX) is a novel , highly selective α2 adrenergic receptor agonists , and its selectivity for α2 receptor is 1600 times higher than α1.It also could provide dose-dependent sedation , analgesia , anti-anxiety and inhibition of sympathetic nerves and other effects .At earlier time It was approved by the FDA only for short-time sedation during mechanical ventilation of adult patients (\<24h) in ICU. 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 gender,such as the drug sensitivity of propofol and remifentanil is increased with age,while the current study also demonstrated that gender may influence the sedate efficacy of propofol and the sensitivity of muscle loose of rocuronium. Current studies with regard to the effects of age and gender on dexmedetomidine pharmacodynamic are rare. The study is aim to explore the right DEX dose of different 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 BIS,during the operation.The relation between BIS values and the depth of sedation for patients is also investigated.

Detailed description: 120 patients scheduled to undergo lower extremity surgery were included in one of three groups. Determination of median effective (ED50) doses was performed by the Dixon and Mood up-and-down method. Initial doses was 1μg/kg, with dose adjustment intervals of 0.05μg/kg, in the youth,and middle-aged group. The initial doses of DEX was 0.7 μg/kg,also with dose adjustment intervals of 0.05μg/kg.Sedative efficacy was defined as an OAA/S of ≤2, or an OAA/S of 3 but with an BIS value of ≤46, 26 min after the beginning of drug administration.

Eligibility criteria: 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:18.5～25

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

Primary outcomes:
measure: The ED50 of DEX
timeFrame: 26min after the start of the infusion
Secondary outcomes:
measure: The ED95 of DEX
timeFrame: 26min after the start of the infusion
Other outcomes:
Locations:
city: Guangzhou
country: China
facility: Guangzhou Military Region General Hospital, Department of Anesthesiology
state: Guangdong
Study officials:
References:
citation: Park SJ, Park HJ, Choi JY, Kang HS, Choi HS. The influence of age and gender on remifentanil EC(50) for preventing rocuronium induced withdrawal movements. Korean J Anesthesiol. 2010 Mar;58(3):244-8. doi: 10.4097/kjae.2010.58.3.244. Epub 2010 Mar 29.
citation: Kodaka M, Johansen JW, Sebel PS. The influence of gender on loss of consciousness with sevoflurane or propofol. Anesth Analg. 2005 Aug;101(2):377-381. doi: 10.1213/01.ANE.0000154534.71371.4F.
citation: Xu B, Li Z, Zhou D, Li L, Li P, Huang H. The Influence of Age on Sensitivity to Dexmedetomidine Sedation During Spinal Anesthesia in Lower Limb Orthopedic Surgery. Anesth Analg. 2017 Dec;125(6):1907-1910. doi: 10.1213/ANE.0000000000002531.