Mouth Occlusion Pressure (P0.1) Provides Valuable Information in the Clinical Assessment and Follow‐up of Ventilatory Drive in Obstructive and Restrictive Lung Disease

Abstract

Ventilatory acclimatization to hypoxia (VAH) includes a time‐dependent increase in minute ventilation with re‐setting of the arterial partial pressure of CO2 “set point” that results in persistent hyperventilation with concomitant changes in arterial oxygen levels. One of the methods used to evaluate the neuromuscular drive to breathe is the airway occlusion pressure (P0.1), which is the pressure generated at the airway opening 100 ms after the onset of occluded inspiratory effort. We hypothesized that P0.1 is a marker of disease that should be follow as a part of the treatment in patients with lung disease, we studied the correlation between P0.1 with FEV1, FVC, FEV1/FVC in patients with lung disease. We retrospectively studied 100 subjects that had PFTs and P0.1 done between September and October 2014. Mean age was 59.3 (range, 19‐89 years). In restrictive lung disease (39/100, 39%) P0.1 was correlated with the FVC and FEV1/FVC, in obstructive lung disease (61/100, 61%) P0.1 was correlated with FEV1 and FEV1/FVC. In subjects with diagnosis of obstructive lung disease P0.1 had a significant correlation with FEV1 and FEV1/FVC (p=0.001 and 0.003), in restrictive lung disease, P0.1 had a significant correlation with FVC (p=0.001) but no significant correlation with FEV1/FVC (p=0.2). Our results showed that P0.1 has a significant correlation with disease severity in lung disease. Previous studies showed that ventilatory drive decreases as a consequence of treatment, and hypoxia correction, is likely that P0.1 is a good marker of disease progression and can help diagnose and guide treatment in both obstructive and restrictive pulmonary disease, more studies are necessary to further evaluate the limitations of the P0.1 in different lung mechanics.