Abstract
Using a chronic sheep preparation, with induced foetal acidosis, the effects of low and high dose thiopentone and ketamine on maternal and foetal cardiovascular dynamics were studied. Ketamine 4 mg·kg-1 and thiopentone 10 mg·kg-1 were both associated with marked reductions in foetal cerebral blood flow and cerebral oxygen delivery. Blood pressure and cerebral blood flow in the acidotic foetus was better preserved, however, following the lower dose of ketamine 2 mg · kg-1 than following thiopentone 6 mg · kg-1.
Résumé
On sait que l’asphyxie et l’acidose provoquent chez le foetus une augmentation du débit sanguin cérébral avec perte du mécanisme d’auto-régulation de cette circulation. Le but du présent travail était d’étudier, dans un contexte d’acidose foetale, les répercussions circulatoires cérébrales de l’administration de deux agents d’induction d’usage courant en anesthésie obstétricale, à savoir la kétamine et le thiopentone. On produisait une acidose chez le foetus de brebis préparées à cette fin. Des doses de kétamine 4 mg · kg-1, de même que des doses de thiopentone 10 mg · kg-1 produisaient dans ces conditions une diminution marquée du débit sanguin cérébral et du transport d’oxygène chez le foetus. La pression artérielle et le débit sanguin cérébral du foetus acidotique se maintenaient mieux lorsque de petites doses (2 mg · kg-1) de kétamine étaient utilisées que lorsque l’on utilisait des doses inférieures (6 mg·kg-1) de thiopentone.
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Presented in part at the Canadian Anaesthetists’ Society Meeting, Edmonton, 1979.
Supported by the Medical Research Council of Canada and the Canadian Heart Foundation.
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Pickering, B.G., Palahniuk, R.J., Coté, J. et al. Cerebral vascular responses to ketamine and thiopentone during foetal acidosis. Canad. Anaesth. Soc. J. 29, 463–467 (1982). https://doi.org/10.1007/BF03009409
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DOI: https://doi.org/10.1007/BF03009409