A New Method for Measuring AIrway Resistance in Man Using a Body Plethysmograph: Values in Normal Subjects and in Patients With Respiratory Disease 1

Satisfactory methods, utilizing measurements of transthoracic or transpulmonary pressure and airflow, are now available for determining "nonelastic" pulmonary resistance. However, the nonelastic pulmonary resistance has two components, tissue resistance and airway resistance, and no valid direct method is available for measuring either of these components separately in man. Since airway resistance is the ratio of alveolar pressure during flow to airflow, airway resistance alone could be measured if there were a method for determining alveolar pressure during flow. This report presents a new method for accomplishing this measurement, and gives data for airway re- sistance obtained in normal subjects and in patients with respiratory disease.