Evaluation of flow limitation in elderly patients unable to perform a forced expiratory maneuver

Background and aims: The assessment of pulmonary function in elderly persons is not often easy in the clinical practice because of poor patient collaboration. A new technique, negative expiratory pressure (NEP), should provide a simple, rapid and non-invasive method for detecting flow limitation without collaboration of the patients. Our aim was to investigate whether it is possible to detect an expiratory flow limitation during resting breathing with NEP in elderly patients unable to perform a forced expiratory maneuver. Methods: In 15 elderly inpatients (4 males and 11 females, mean age 83+/-4.7 SD years) unable to realize the classical forced expiratory maneuver because of poor coordination or cognitive disturbance, we applied the NEP technique during spontaneous breathing. Results: NEP application during resting breathing was easily and rapidly performed in all cases without side effects. During NEP (-5cmH2O and NEP-10cmH2O), 6 and 5/15 patients were flow limited; mean flow limitation was 60+/-9% and 70+/-15% respectively. These results were reproducible with repeated NEP tests. Conclusions: Application of negative pressure at the mouth during tidal expiration provides a simple method for detecting expiratory flow limitation during spontaneous breathing in elderly patients with poor collaboration.