404 OF RESPIRATION. 



by M. Jousset that direct injection through the trachea is a means by which 

 quinine may be made to enter the system rapidly, when the state of the 

 cutaneous circulation and the irritability of the stomach render it useless to 

 administer it either by the stomach or by subcutaneous injection. 1 



3. Effects of Suspension or Deficiency of Respiration. 



323. We have now to consider the results of the cessation of the Respira- 

 tory function, and the consequent deficiency in the supply of Oxygen and 

 retention of Carbonic acid in the blood. If this be sufficiently prolonged, a 

 condition ensues to which the name of Asphyxia has been given, the essential 

 character of which is the cessation of muscular movement, and shortly after- 

 wards of the Circulation ; with an accumulation of blood in the venous system. 

 The time which is necessary for life to be destroyed by Asphyxia varies 

 much, not only in different animals, but in different states of the same. 

 Thus, warm-blooded animals are much sooner asphyxiated than Reptiles or 

 Invertebrata; on the other hand, a hibernating Mammal supports life for 

 many mouths, with a respiration sufficiently low to produce speedy asphyxia 

 if it were in a state of activity. And among Mammalia and Birds, there 

 are many species which are adapted, by peculiarities of conformation, to sus- 

 tain a deprivation of air for much more than the average period. 2 Exclud- 

 ing these it may be stated as a general fact, that if a warm-blooded animal 

 in a state of activity be deprived of respiratory power, its muscular move- 

 ments (with the exception of the contraction of the heart) will cease within 

 five minutes, often within three; and that the circulation generally fails 

 within ten minutes. In the experiments made by the Committee of the 

 Royal Medico-Chwairgical Society, 3 which are corroborated by the more 

 recent ones of M. P. Bert, 4 it was found that when death by drowning took 

 place rapidly, it was due to the entrance of Water into the lungs; and that 

 if the entrance of air into the lungs was prevented by suddenly inserting 

 a cork into a glass tube tightly tied into the trachea, the average duration 

 of the efforts to inspire was 4 minutes 5 seconds in dogs, and 3 minutes 25 

 seconds in rabbits; whilst the average duration of the heart's action was 7 

 minutes 11 seconds in dogs, and 7 minutes 10 seconds in rabbits. It was 

 found also that in simple occlusion of the trachea recovery might take place 

 after deprivation of air for 3 minutes 50 seconds, whilst immersion for I? 

 min.was usually fatal. M. Brown-Sequard 5 has shown by numerous experi- 

 ments, that both newly-born animals and adults are capable of resisting 

 the Asphyxia which results from submersion, by so much longer a period as 

 their temperature is lower, providing it does not descend below 64 F. As 

 a general rule, the newly-born animal can survive submersion for a longer 

 period than the adult; this, however, does not hold in the case of guinea-pigs. 

 Of 14 newly-born rabbits submersed in water at 77 F., 5 had a tempera- 

 ture of 96 F., and survived, on the average, 12'> minutes; 4 had a tempera- 

 ture of 82 to 89 F., and survived 17 minutes; lastly, 5 had a temperature 



1 Claude Bernard, Lemons sur les Anaxsthesiques, 1875, p. 74. 



2 Thus, the Cetacea contain far more blood in their vessels than do any other 

 Mammalia ; and these vessels are so arranged, that both arteries and veins are in 

 connection with larfie reservoirs or diverticula. The reservoirs belonging to the 

 former are usually full ; but when the Whale remains long under water, the blood 

 which they contain is gradually introduced into the circulation, and after becoming 

 venous, accumulates in the reservoirs connected with the venous system. By means 

 of this provision, the Whale can remain under water for more than an hour. 



Trims., vol. xlv. p. 449. Gaz. Medicale, 1865, p. 79. 



6 Journal de la Phys., vol. ii, p. 98 et seq. 



