Effects of inhalation anesthetics on carotid body chemoreceptor activity
Arima, T.
Masui. Japanese Journal of Anesthesiology 33(5): 474-481
1984
ISSN/ISBN: 0021-4892 PMID: 6471368 Document Number: 225744
Halothane and nitrous oxide are known to inhibit the ventilatory responses to hypoxia and hypercapnia. To determine whether these inhibitions were mediated by peripheral chemoreceptors, the effect of halothane and nitrous oxide on the response of carotid body chemoreceptors to NaCN was measured. In a puppy anesthetized with nitrous oxide-oxygen-halothane (GOF), the right carotid sinus was denervated by dissection of the baroreceptor elements, and the mean integrated carotid body chemoreceptor discharge, onset time and duration time were recorded. Chemoreceptor activity to the intra-aortic administration NaCN (8 .mu.g/kg) with GOF was studied. Nitrous oxide 60% reduced this to .apprx. 78.9%. Halothane 0.5% with nitrous oxide 60% reduced this to .apprx. 62.9% of the control value. Halothane 1.0% with nitrous oxide 60% reduced this to .apprx. 47.0% of the control value. Halothane 1.5% with nitrous oxide 60% reduced this to .apprx. 28.3% of the control value. Halothane 2.0% with nitrous oxide 60% reduced this to .apprx. 18.6% of the control value. The onset time of the response to NaCN for carotid body chemoreceptor was 2.6 .apprx. 2.9 s, and this was not affected with any concentration of halothane or nitrous oxide. The duration of response to NaCN for carotid body chemoreceptor was not affected with any concentration of halothane or nitrous oxide.