RESPIRA TION 



215 



experiment the inflation is produced through a tube introduced 

 through the glottis. If the animal is not to be kept alive, the 

 apparatus is generally connected with a cannula in the trachea. 

 In man the exchange of air between the atmosphere and the 

 lungs may be most readily accomplished by strong rhythmical 

 compression of the lower part of the chest. This forces out some 

 of the air from the lungs ; on relaxing the pressure the chest 

 expands again and air is drawn in. Schafer has shown that 

 this is the most efficient method of respiration in resuscitation 

 of the apparently drowned. ' The patient is placed face down- 

 wards on the ground, with a folded coat under the lower part of 

 the chest. The operator puts himself athwart or at the side of 

 the patient, facing his head and kneeling upon one or both 

 knees (Fig. 98), and places his hands on each side over the lower 

 part of the back (lowest ribs). He then slowly throws the weight 



FIG. 98. ARTIFICIAL RESPIRATION IN CASES OF DROWNING (AFTER SCHAFER). 



of his body forward to bear upon his own arms, and thus presses 

 upon the thorax and forces air out of the lungs. He then gradually 

 relaxes the pressure by bringing his own body up again to a more 

 erect position, but without moving the hands.' Air is thus 

 drawn into the lungs. The process is repeated twelve to fifteen 

 times a minute. 



Certain accessory phenomena (movements and sounds) are 

 associated with the proper movements of respiration. The 

 larynx rises in expiration, and sinks in inspiration. The glottis 

 (and particularly its posterior portion, the glottis respiratoria) 

 is widened during deep inspiration and narrowed during deep 

 expiration. The same is the case with the nostrils, and, indeed, 

 in some persons the alse nasi move even in ordinary breathing. 

 It has long been known that in deep respiration changes in the 

 calibre of the bronchi synchronous with the respiratory move- 



