Abstract
The influence of arterial O2 and CO2 tensions on electroconvulsive seizure duration was investigated in five mongrel dogs under consistent anaesthetic conditions. Seizure durations were measured in a randomized protocol of nine possible combinations of arterial gas tension spanning increased, normal or decreased levels of PaO2 and PaCO2. Seizure duration was directly related to PaO2 (p < 0.00001) and inversely related to PaCO2 (p < 0.0001). A significant synergism was evident at the extremes of PaO2 and PaCO2, with seizure duration being greater than predicted for hyperoxia-hypocapnia and hypoxia-hypercapnia and shorter than predicted for hypoxiahypocapnia and hyperoxia-hypercapnia. We conclude that arterial gas tensions strongly influence ECT-induced seizure duration and through this may influence the therapeutic efficacy of electroconvulsive therapy.
Résumé
On a examiné ľinfluence de pression artérielle de 02 et de C02 sur la durée des convulsions produites par sismothérapie, chez cinq chiens bâtards dans des conditions anesthésiques identiques. Afin de mesurer les durées de convulsions, on a utilisé un protocole aléatoire de neuf combinaisons possibles de la pression artérielle du gaz s’étendant à des niveaux de Pa02 et de PaCO2 élevés, normaux, ou diminués. La durée de convulsions était directement reliée à la PaO2 (p < 0.00001) et inversement reliée à la PaCO2 (p < 0.0001), Un synergisme significatif se manifestait aux extrêmes de la PaO2 et de la PaCO2, accompagné ďune durée de convulsions plus élevée que prévu pour ľhyperoxie-hypocapnie et ľhypoxie-hypercapnie et plus courte que prévu pour ľhypoxie-hypocapnie et hyperoxiehypercapnie. Nous concluons que les pressions artérielles du gaz influencent grandement la durée de convulsions induites par sismothérapie et peuvent ainsi influencer ľefficacité thérapeutique de la sismothérapie.
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Douglas, C., Butler, P. & Froese, A. Arterial PaO2 and PaCO2 influence seizure duration in dogs receiving electroconvulsive therapy. Can J Anaesth 34, 437–441 (1987). https://doi.org/10.1007/BF03014344
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DOI: https://doi.org/10.1007/BF03014344