Children
Conditions
Keywords
dexmedetomidine, sevoflurane, MAC bar, drug interaction, anesthesia
Brief summary
The study was designed to define the interaction of intravenous infusion of dexmedetomidine, an a2-adrenergic agonist, and sevoflurane in children having surgery by using the minimum alveolar concentration which can block adrenergic and cardiovascular responses to incision(MACbar) of sevoflurane as the measure of anesthetic potency.
Detailed description
The investigators observed the effects of different doses of dexmedetomidine on the minimum alveolar concentration of sevoflurane to blockade adrenergic response to surgical incision in 50% of children (MACBAR). And to explore the safety of use of dexmedetomidine in pediatric patients.
Interventions
DRUGdexmedetomidine
children received intravenous infusion with a bolus dose dexmedetomidine and followed by a continuous infusion before induction. use sevoflurane for induction and a steady-state end-tidal sevoflurane concentration was maintained for at least 15 min before skin incision.
Sponsors
Cai Li
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Masking
DOUBLE (Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
2 Years to 6 Years
Healthy volunteers
No
Inclusion criteria
* aged 2 to 6 yr * American Society of anesthesiologists I or II * scheduled to have general anesthesia and to have skin incisions on the abdomen
Exclusion criteria
* anemia or abnormal preoperative electrolyte concentrations * a history of cardiovascular or central nervous system diseases * a history of pulmonary disease * known hepatic or renal disease * a body weight exceeding 50% of the upper limit of ideal body weight for height * taking drugs with cardiovascular or central nervous system effects * use of any experimental drug within the past 30 days * allergy to any drug that may be administered during the study * exposure to general anesthesia within the previous 7 days * second- or third-degree atrioventricular block * taking drugs preoperatively that would interfere with MAC determination(e.g.,opioids or sedatives)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| the end-tidal sevoflurane concentration to blockade adrenergic response to surgical incision in 50% of children (MACBAR) | at once before incision and 5 min period after incision | A predetermined steady-state end-tidal sevoflurane concentration(4%) was maintained for at least 15 min before skin incision.we observed the change in Mean Blood Pressure or Heart rate to determined the next end-tidal sevoflurane concentration.Followed the modified Dixon up and down method to obtain MACBAR of every child.The MACBAR of sevoflurane and its 95% confidence interval were calculated by Sum Average method. |
Outcome results
None listed