title: A new device for measurement of pulmonary pressure-volume curves in patients on mechanical ventilation.
abstract: Measurement of total (lung plus chest wall) pulmonary compliance is routinely obtained in mechanically ventilated patients by dividing the tidal volume (VT) by the airway pressure (Paw) gradient from end-inspiration to end-expiration. In order to obtain the pressure-volume (P-V) tracing during inspiration, we developed a method using a continuous and slow (1.7 L/min) oxygen inflow. When gas flow is kept constant, changes in lung volume are proportional to time and do not require direct measurement. In 22 patients, P-V curves traced using the continuous-flow method were identical to those obtained from the syringe method. The advantages of the inflow method are simplicity, reproducibility, and better visualization of the initial part of P-V curve.
mesh_terms: D006801:Humans; D008171:Lung Diseases / Q000503:physiopathology; D008176:Lung Volume Measurements / Q000379:methods*; D012123:Pulmonary Ventilation; D012121:Respiration, Artificial