1. The potential value of right vagotomy for the relief of breathlessness has been explored in five patients with emphysema. Two patients had symptomatic improvement, two had minor symptomatic improvement, and one was unchanged. 2. Exercise ventilation was not noticeably depressed by unilateral right vagotomy in the two patients investigated fully, but the pattern of breathing was altered. After vagotomy, breathing was deeper, and the rise in the frequency of breathing with exercise was depressed. 3. After right vagotomy the response to rebreathing carbon dioxide also consisted of slower deeper breaths. 4. Right vagotomy sometimes appears to remove an influence preventing slow deep breathing and exacerbating dyspnoea. 5. Results of bilateral pulmonary denervation, attempted in one patient, were complicated by the need for left thoracotomy, which removed any possible beneficial effects.
1. The breathing pattern in normal subjects during exercise was compared with that in patients with obstructive and restrictive lung defects. 2. In most normal women and patients with obstructive or restrictive lung disease, as the frequency of breathing increased both inspiratory and expiratory duration fell. However, in most normal men (74%) inspiratory duration did not fall as ventilation increased. 3. Women breathed faster than men, and both obstructed and restricted patients breathed faster than normal subjects. 4. The airflow patterns in normal men and women were similar, but most patients with restrictive or obstructive lung disease showed an approximately exponential fall in flow during expiration.
1. The cardiogenic oscillations in the concentration of nitrogen and argon in expired gas, which are seen after the inspiration from residual volume of pure oxygen or a bolus of argon, have been studied in normal subjects and in patients with atrial fibrillation. 2. In the upright position of the subject, the peaks of nitrogen and argon concentration coincide with ventricular systole, although there is a transit delay along the tracheobronchial tree before any change of concentration occurs at the mouth. 3. Studies in different postures demonstrated that the effect of the heart is predominantly due to a reduction in cardiac volume during systole with a decrease in airflow from regions adjacent to the heart. These areas contain a different concentration of nitrogen and argon in the alveolar air from the more apical regions. 4. It has been shown that the results are consistent with the present concepts of the influence of gravity on the distribution of inspired air.