Dangers of positive pressure respiration breathing with special reference to the so-called "surfactant factor"

Atelectasis and emhysema have been induced in rabbits after anaesthesia and IPPB for one hour at 30 cm water pressure. The pulmonary surfactant became coarsely granular and appeared in the form of large drops. A correlation is suggested to exist between this phenomenon and the atelectasis and emphysema which developed during IPPB.