The tolerance of lung of unanesthetized male rats to rapid decompression from one atmospheric pressure to an ambient pressure of 30 mm Hg in 0.3 s was markedly reduced when the rats were previously subjected to prolonged semi-starvation for 1.5 to 3 months. It was observed that 46.7% of the control animals revealed mild pulmonary hemorrhage, while all of the semi-starved rats (100%) exhibited mild to severe pulmonary hemorrhage. Besides, the average dry lung weight of the control group was 406 mg while the value for the semi-starved animals was 279 mg. The difference was highly significant statistically. The significant weight loss of the lung could indicate certain degree of lung atrophy. Such an atrophy of pulmonary tissue might be responsible for the decreased tolerance of lung to rapid decompression. The frequency of occurrence and the severity of the pulmonary hemorrhage may thus be increased.
