Hypocapnia attenuates, and nitrous oxide disturbs the cerebral oximetric response to the rapid introduction of desflurane.
J Korean Med Sci
; 24(6): 1051-7, 2009 Dec.
Article
em En
| MEDLINE
| ID: mdl-19949659
ABSTRACT
The aim of this study was to develop a nonlinear mixed-effects model for the increase in cerebral oximetry (rSO(2)) during the rapid introduction of desflurane, and to determine the effect of hypocapnia and N(2)O on the model. Twelve American Society of Anesthesiologist physical status class 1 and 2 subjects were allocated randomly into an Air and N(2)O group. After inducing anesthesia, desflurane was then increased abruptly from 4.0 to 12.0%. The PET(CO2), PET(DESF) and rSO(2) were recorded at 12 predetermined periods for the following 10 min. The maximum increase in rSO(2) reached +24-25% during normocapnia. The increase in rSO(2) could be fitted to a four parameter logistic equation as a function of the logarithm of PET(DESF). Hypocapnia reduced the maximum response of rSO(2), shifted the EC(50) to the right, and increased the slope in the Air group. N(2)O shifted the EC(50) to the right, and reduced the slope leaving the maximum rSO(2) unchanged. The N(2)O-effects disappeared during hypocapnia. The cerebrovascular reactivity of rSO(2) to CO(2) is still preserved during the rapid introduction of desflurane. N(2)O slows the response of rSO(2). Hypocapnia overwhelms all the effects of N(2)O.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oximetria
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Córtex Cerebral
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Circulação Cerebrovascular
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Hipocapnia
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Anestésicos Inalatórios
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Isoflurano
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Óxido Nitroso
Tipo de estudo:
Clinical_trials
Limite:
Adult
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Korean Med Sci
Assunto da revista:
MEDICINA
Ano de publicação:
2009
Tipo de documento:
Article