Anesthesia alters the pattern of aerosol retention in hamsters.

General anesthesia was used to produce nonventilated areas of the lung, and aerosol inhalation was used to locate these areas, assuming that no aerosol deposits in a nonventilated region. Male Syrian golden hamsters were anesthetized with pentobarbital sodium (90 mg/kg), which reduced respiratory frequency, tidal volume, minute volume, and O2 consumption to 61, 41, 24, and 36%, respectively, of the corresponding awake levels. Awake and anesthetized hamsters were exposed to the aerosol for 30 min; then the lungs were excised, dried at total lung capacity, sliced into sections, and dissected into pieces.

Breathing patterns influence aerosol deposition sites in excised dog lungs.

Particles' suspended in inhaled air can deposit on lung surfaces. The amount deposited in different lung regions is determined by distribution of ventilation and local efficiency of particle collection. We examined how the pattern of ventilation influences sites of aerosol deposition in excised dog lungs.

Species differences in aerosol deposition.

A theory for scaling the collection efficiency of the lung and respiratory tract is developed by identifying the dimensionless groups of variables controlling the deposition of an inhaled aerosol. The theory predicts that collection efficiency is substantially independent of body size under physiologically equivalent conditions. Thus, total deposition depends primarily on differences in ventilation per gram body weight.