Variability in the size of airspaces in normal human lungs as estimated by aerosols.
Measurement of persistence, expressed as half-life (t1/2), of a monodisperse aerosol during breath holding was interpreted as an indirect estimate of the size of intrapulmonary airspaces in healthy subjects. Within subject variation of t1/2 measured over a period of nearly two years was small (coefficient of variation 7-7 to 11-5%). Mean effective airspace diameters were calculated from the aerosol t1/2 values using the settling term from the equation of Landahl (1950). Calculated mean airspace diameters ranged from 0-30 to 0-79 mm for 36 males and from 0-40 to 0-62 mm for 12 females. Airspace diameters correlated poorly with age, height, weight, and lung volumes. These results suggest marked differences in airways geometry in subjects with similar heights and lung volumes.
D000328:Adult; D000336:Aerosols; D000367:Age Factors; D000403:Airway Resistance; D001827:Body Height; D001835:Body Weight; D002248:Carbon Monoxide; D005260:Female; D006207:Half-Life; D006801:Humans; D008176:Lung Volume Measurements; D008297:Male; D012129:Respiratory Function Tests; D012737:Sex Factors; D012907:Smoking / Q000503:physiopathology; D013147:Spirometry; D013730:Terphenyl Compounds; D014797:Vital Capacity
D000336:Aerosols; D013730:Terphenyl Compounds; D002248:Carbon Monoxide