Regional expiratory flow limitation studied with Technegas in asthma.

@article{Pellegrino2001RegionalEF,
  title={Regional expiratory flow limitation studied with Technegas in asthma.},
  author={Riccardo Pellegrino and Alberto Biggi and Alberto Papaleo and Gianfranco Camuzzini and Joseph R. Rodarte and Vito Brusasco},
  journal={Journal of applied physiology},
  year={2001},
  volume={91 5},
  pages={
          2190-8
        }
}
Regional expiratory flow limitation (EFL) may occur during tidal breathing without being detected by measurements of flow at the mouth. We tested this hypothesis by using Technegas to reveal sites of EFL. A first study (study 1) was undertaken to determine whether deposition of Technegas during tidal breathing reveals the occurrence of regional EFL in induced bronchoconstriction. Time-activity curves of Technegas inhaled during 12 tidal breaths were measured in four asthmatic subjects at… 
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