Comparison of the ventilation response to CO2 rebreathing in healthy smokers and nonsmokers and subjects with bronchitis.

A comparison of ventilatory tests and the response to carbon dioxide rebreathing was made in healthy smokers, nonsmokers, and in subjects with bronchitis. The response to carbon dioxide (CO2) rebreathing was the same in the healthy population but diminished in the bronchitic group. Effects of smoking on maximal expiratory flow rates did not correlate with the results of carbon dioxide rebreathing.

The effects of proprandolol and histamine on the ventilation response to carbon dioxide inhalation in normal subjects.

A method was developed to measure the oxygen cost of ventilation during CO2 rebreathing. In 20 healthy normal subjects SGaw, MMEF, and FEV1 were measured prior to and following the infusion of propranolol. In five of the same subjects airway constriction was induced by inhalation of histamine.