TERTIARY BLAST EFFECTS: THE EFFECTS OF IMPACT ON MICE, RATS, GUINEA PIGS AND RABBITS
Technical progress rept.
LOVELACE FOUNDATION FOR MEDICAL EDUCATION AND RESEARCH ALBUQUERQUE NM
Pagination or Media Count:
A total of 455 mice, rats, guinea pigs and rabbits were subjected to impact at velocities ranging between 25 ftsec and 51 ftsec. The desired velocities were generated by allowing the animals to free-fall from various heights to a flat concrete pad. The ventral surface of each animal was the area of impact. Probit analyses of the 24-hr mortality data yielded LD50 impact velocities with 95 per cent confidence limits as follows mouse, 39.4 37.4-42. 0 ftsec rat, 43.5 42.0 - 44.8 ftsec guinea pig, 31.0 30.0 - 31.9 ft sec. The LD50 figures for the mouse and rat were significantly higher, statistically, than those for the guinea pig and rabbit. The small spread in the LD50 values suggested little variation in the tolerance of biological systems to impact. Further, the steepness of the mortality curves indicated a narrow survival range to impact. Extrapolation of the experimental data to the 70 kg animal yielded a predicted LD50 impact velocity of 26 ftsec 18 mph. Literature relevant to the human case was reviewed and the tentative applicability of the predicted figures to adult man was discussed. Author