Related Experiment Video
Updated: Aug 17, 2026

Phase-Resolved Functional Lung MRI for Pulmonary Ventilation and Perfusion (V/Q) Assessment
Published on: August 9, 2024
[Increase in functional residual capacity induced by positive end-expiratory pressure. Prediction using the
Abstract:
Prediction of FRC using a respiratory P-V curve (2 1 syringe method) has been tested in eight patients with normal lungs and in 12 ARDS patients. FRC was measured using nitrogen dilution technique with a closed circuit. Correlation between measured and predicted FRC was excellent, especially when the expiratory limb of the P-V curve was used (r = 0.92, in patients with pulmonary edema, and r = 0,97 when patients were evaluated after a few weeks). PEEP induced increase in FRC was larger between 10 and 20 cmH2O than between 0 and 10 cmH2O. As expected, Qs/Qt decrease was correlated with the FRC augmentation.
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