Читать книгу Respiratory Medicine - Stephen J. Bourke - Страница 81

In addition to FEV₁ and FVC, a number of other indices may be calculated from a forced expiratory spirogram. The forced expiratory flow measured over the middle half of expiration (FEF _25–75% ) reflects changes in the smaller peripheral airways, whereas FEV₁ and peak expiratory flow (PEF) particularly are predominantly influenced by diffuse changes in the medium‐sized and larger central airways, at least in health (see Chapter 1).