JAMES A. MILLER, JR. 



241 



could have been saved by artificial respiration and various other treat- 

 ments. 



Figure 1- shows that in the range from 43° to 20°C survival time 

 increases approximately 50% per 10° decrease in body temperature. Below 

 20°C cooling is increasingly effective on the average, in spite of the fact 

 that morbidity from hypothermia was obvious in a number of the animals 

 (c.f. 122, 119). As temperatures were reduced further animals actually 

 died from secondary effects of low temperature before exposure. 



Tiie time of death and temperature of the longest and shortest-lived 

 animals are also illustrated on the graph. The longest survival (617 

 seconds) was that of a 14°C animal. It lived more than 7V^ times as 

 long as the shortest-lived animal (81 seconds) whose body temperature 

 was 42.8°C. The 10 shortest-lived animals with a mean temperature of 

 42.8°C averaged 95 seconds survival. The 10 longest-lived animals, with 

 a mean body temperature of 14.9°C, averaged 548.9 seconds (120). These 



* Condensation of table 2, Miller and Miller, 1954. 



experiments prove that hypothermia is effective in delaying asphyxial 

 death when induced before asphyxiation. In a second series of experiments, 

 it was found that when cooling was begun after loss of consciousness 

 from asphyxia, a significant increase in survival time could still be 

 demonstrated (table 2). 



The effect of temperature upon asphyxial survival has been tested on 

 two species which are less rather than more mature at birth than man. 

 In figure 2 is plotted the time of death and temjjerature of 18 newborn 

 rabbits. Littermates are connected by lines. It shows that not only are 

 rabbits far more resistant to asphyxia than guinea pigs at normal body 

 temperature, but also that the protection against asphyxia conferred 

 upon them by cooling is almost three times that observed in the guinea 

 pig. Figure 3 shows the times of death of a litter of six neonatal puppies 

 at various body temperatures. Hypothermia is even more effective here 

 than in the newborn rabbit in protecting against asphyxial death. From 

 general considerations one might expect the human baby to react more 



-Curve drawn from 4''C means published in table 1, Miller and Miller (122). 



