Regional distribution of intraesophageal pressure in normal and emphysematous subjects

Abstract

If sufficiently large pressure differences were to develop between the pulmonary air spaces of one region and another during ventilatory efforts, then it is possible that septal ruptures such as seen in emphysema might result. It was the purpose of this study to explore this possibility. Intraoral airway pressure and intraesophageal pressure at three esophageal levels were measured simultaneously and continuously in 5 normal subjects and 10 patients with varying degrees of chronic obstructive pulmonary disease. No significant regional pressure difference developed in the segments of lung adjacent to the esophagus in any subject during static respiratory efforts against a closed valve or during strenuous dynamic respiration with maximum voluntary ventilation. These results are negative with respect to the pathogenesis of emphysema since large pressure differences along the lung surface were not demonstrated. The remarkable similarity of intraoral airway pressure and the intraesophageal pressures during the static part of the study is further evidence validating the intraesophageal approach to the measurement of intrathoracic pressure in diseased as well as normal subjects. intrathoracic pressure; lung stress mechanics of ventilation; pathogenesis of emphysema Submitted on June 9, 1964