Effects of SGB on the ventilatory response of bronchial asthmatic patients to step-wise changes in end-tidal carbon dioxide concentration under low FIO₂ level

Abstract

To assess the applicability of the stellate ganglion block (SGB) to asthmatic patients, ventilatory response to step-wise changes in end-tidal carbon dioxide concentration was analyzed with FIO₂ levels lower than 20% and higher than 60% in 10 stable bronchial asthmatics (5 men and 5 women, aged between 26-65, mean 49.4); and under low FIO₂ conditions in 5 volunteer controls (4 men and 1 woman, aged 26-50, mean 35.8).
After SGB, ventilatory response to carbon dioxide under conditions of higher than 60% inspired oxygen concentration and lower than 20% inspired oxygen concentration was not impaired. The ventilatory response to carbon dioxide in bronchial asthmatics under mild hypoxia was not different from that in controls.
We may conclude that SGB can be safely done in bronchial asthmatic patients while they are mildly hypoxic.