Minimal alveolar concentration of sevoflurane inhibiting the reflex pupillary dilatation after noxious stimulation in children and young adults.
Br J Anaesth
; 108(4): 648-54, 2012 Apr.
Article
em En
| MEDLINE
| ID: mdl-22265901
ABSTRACT
BACKGROUND:
In children, sevoflurane is the most commonly used anaesthetic. Its excellent haemodynamic tolerance gives it a wide therapeutic index. This halogenated agent can abolish movement [minimal alveolar concentration (MAC)] or haemodynamic responses (MACBAR) to noxious stimulus in children as in adults. Reflex pupillary dilatation (RPD) has been demonstrated as a very sensitive measure of noxious stimulation. In order to investigate the effect of sevoflurane on the RPD, a subcortical reflex, we determined the MAC of sevoflurane inhibiting the RPD in 50% of the subjects in response to skin incision (MACpup) in pre- and post-pubertal subjects.METHODS:
We included 30 pre-pubertal children and 19 post-pubertal subjects. Patients received sevoflurane at preselected concentrations according to an 'up and down' design, and after a steady-state period, skin incision was performed. The RPD was considered as significant when the pupillary diameter increased by more than 100%. Heart rate (HR) and bispectral index (BIS) changes were analysed according to the pupillary response.RESULTS:
The MACpup of sevoflurane was 4.8% (95% confidence interval, 4.6-5.1%) in pre-pubertal children vs 3.4% (3.5-3.3%) in post-pubertal subjects (P<0.001). Inhibition of RPD was always associated with lack of significant HR response. In pre-pubertal children receiving high concentrations of sevoflurane, RPD in response to noxious stimulation was frequently associated with lack of HR response and low BIS values.CONCLUSIONS:
MACpup was higher than MAC and close to the MACBAR. Inhibition of RPD in pre-pubertal children required higher sevoflurane concentrations compared with post-pubertal subjects, suggesting that the relationship between the brain structure sensitivities may differ with brain maturation.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Alvéolos Pulmonares
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Reflexo Pupilar
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Anestésicos Inalatórios
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Procedimentos Cirúrgicos Dermatológicos
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Éteres Metílicos
Tipo de estudo:
Clinical_trials
/
Observational_studies
/
Risk_factors_studies
Limite:
Adolescent
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Child
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Child, preschool
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Humans
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Infant
Idioma:
En
Revista:
Br J Anaesth
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
França