Propofol for pediatric tracheal intubation with deep anesthesia during sevoflurane induction: dosing according to elapsed time for two age groups.
OBJECTIVE
To determine, for two different age groups, the effect of duration of sevoflurane administration on the amount of propofol needed when performing tracheal intubation.


METHODS
Classic Dixon's Up-and-Down sequential method.


METHODS
University based operating rooms.


METHODS
106 ASA physical status 1 and 2 patients aged one to 11 years.


METHODS
Patients were allocated to the 1-6 year (≥ 12 and < 72 mos) and 6-11 year (≥ 72 and < 132 mos) age groups. Midazolam 0.5 mg/kg was given orally to the 1-6 year group, and all patients were induced with 8% dialed sevoflurane and 67% nitrous oxide (N2O), with N2O discontinued and sevoflurane dialed to 5% after one minute and 1.5 minutes for the younger and older age groups, respectively. Intravenous access was obtained and propofol was promptly administered. Propofol dose was determined according to age group and whether propofol was given 2-4, 4-6, or 6-8 minutes after the start of sevoflurane induction, with Dixon's Up and Down Method used separately for each specific age/time group. Tracheal intubation conditions one minute after propofol were evaluated.


METHODS
Isotonic regression determined propofol ED50 estimates for excellent tracheal intubation conditions, and linear regression determined the effect of propofol dose on change in systolic blood pressure (SBP).


RESULTS
Estimated propofol ED50 doses for 1-6 year olds, with 95% confidence intervals (CIs), were 1.48 mg/kg (0.80, 2.03), 0.00 mg/kg (0.00, 0.38), and 0.07 mg/kg (0.00, 0.68) in the 2-4, 4-6, and 6-8 minute groups, respectively, with estimated differences between the 2-4 minute group versus the 4-6 and 6-8 minute groups being 1.47 mg/kg (95% CI = 1.04, 2.06) and 1.41 mg/kg (95% CI = 0.74, 2.04), respectively. Estimated propofol ED50 doses for 6-11 year olds, with 95% CIs, were 2.35 mg/kg (1.97, 2.45) and 2.33 mg/kg (1.59, 2.45) in the 2-4 and 4-6 minute groups, respectively. Diminutions in SBP at one minute and two minutes after propofol administration were dose dependent for children 1-6 years of age, decreasing 5.3% and 8.1% for each 1 mg/kg of propofol, respectively.


CONCLUSIONS
The amount of propofol needed to supplement sevoflurane in children 1-6 years of age can be expected to decrease after 4 minutes of sevoflurane.
Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA 22908, USA. Electronic address: gdp8a@virginia.edu.
George D
GD
Politis
Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA 22908, USA.
Christopher J
CJ
Stemland
Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA 22908, USA.
Ravi K
RK
Balireddy
Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA 22908, USA.
Julie
J
Brockhaus
Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA 22908, USA.
Kevin R
KR
Hughes
Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA 22908, USA.
Matthew D
MD
Goins
Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA 22908, USA.
Timothy L
TL
McMurry
D000367:Age Factors; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D018686:Anesthetics, Intravenous / Q000008:administration & dosage; D001794:Blood Pressure / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D054810:Deep Sedation / Q000379:methods*; D054796:Drug Dosage Calculations; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007223:Infant; D007442:Intubation, Intratracheal / Q000379:methods*; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage*; D010372:Pediatrics / Q000379:methods; D015742:Propofol / Q000008:administration & dosage*; D000077149:Sevoflurane; D013997:Time Factors
D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D008738:Methyl Ethers; D000077149:Sevoflurane; D015742:Propofol
Anesthesia: inhalational intratracheal, intravenous; Intubation intratracheal; Pediatrics