|
KMID : 0383119640120010047
|
|
Journal of Aerospace Medicine
1964 Volume.12 No. 1 p.47 ~ p.55
|
|
|
Effects of Repeated Exposure to Rapid Decompression and Effects of Chlorpromazine Injection
|
|
|
|
|
Abstract
|
|
|
I. In order to study the residual effects of exposure to rapid decompression, 15 male rabbits were repeatedly exposed to rapid decompression (to 53, 000 ft -- for 1 min) every other day on 5 occasions. Observations were made on the changes in white blood cell, red blood cell and eosinophil counts, hematocrit ratio and hemoglobin concentration. The measurements were made before the first exposure and 3 hours after the last.
The red blood cell count and hematocrit ratio revealed only insignificant changes. However, both white blood cell and eosinophil counts , increased. As for the tolerance of animals, only 50 percent of the animals survived and the rest died during the course of exposure. Pathological examination of the lungs revealed atelectasis of a severe degree, hemorrhagee and ruptured alveoli. Reddish. discoloration of the lung surface was observed on macroscopic examinations. These results indicate that there exist certain cumulative residual effects of a rapid decompression, which ´would eventually bring the animal to the termination- of life upon repeated exposures.
II. As indicated, the only remarkable pathological finding after an exposure to a rapid decompression was noted in the lung, as manifested by hemorrhage and atelectasis. Interestingly enough, these changes are strikingly similar to those obtained during oxygen poisioning. In the latter case, it has been shown by Gerschman et al. (1955) that chlorpromazine prevents the occurrence of such changes in the lung. Hence, attempts have been made to study the effect of chlorpromazine during a rapid decompression. Twenty male- rabbits were exposed to rapid decompression 20 min after chlorpromazine injection. Similar results as reported by Kay (1963) were obtained except for pathological findings of the lung. Three hours after a rapid decompression, the lung showed only severall petechiae in the upper and middle lobes, and microscopically atelectasis and hemorrhagic signs of a slight degree. All animal survived the exposure for 1 min and 30 sec of rapid decompression to 54,000 feet. One animal even survived the exposure for 2 min and 30 sec of rapid decompression to 53, 000 feet., Considering the above results, the tolerance seemed to be increased to some extent by chlorpromazine administration. These results indicate that chlorpromazine has a definite protective effect to a rapid decompression in terms of pulmonary pathology as well as of survival. However, the underlying mechanism for this protective effect is not clear at present.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|
|