140 ADVANCED LESSONS IN PRACTICAL PHYSIOLOGY 



4. Influence of Carbon Dioxid. Compress the nostrils of the sub- 

 ject and allow him to breathe from and into a rubber bag containing 

 about 30 liters of air. As soon as the CO 2 has accumulated sufficiently 

 the subject will breathe more rapidly and more deeply until his rate is 

 about forty to the minute. Stop the experiment soon after the occur- 

 rence of the hyperpnea. 



Repeat this experiment after having interposed a receptacle of 

 1 or 2 liters capacity containing soda-lime or sticks of sodium hydrate. 

 The carbon dioxid will be absorbed, while the oxygen in the bag is being- 

 used up. Consequently, there will be no hyperpnea. Only a few 

 minutes will be required to establish this fact. Immediately allow the 

 subject to breathe normal air, otherwise the oxygen deficiency will lead 

 to cyanosis, frontal headache, and unconsciousness. 



5. Artificial Respiration. Familiarize yourself with the Sylvester 

 and Schafer methods of artificial respiration. Place the subject upon 

 his back with the feet somewhat elevated. Take a position at the head 



FIG. 88. POSITION TO BE ADOPTED FOR EFFECTING ARTIFICIAL RESPIRATION IN CASE> 

 OF DROWNING. (Sc.haefer.) 



of the subject and grasp his wrists. Now bring the forearms against 

 the sides of the chest and press gently inward and downward against 

 the ribs. Release the pressure, allowing the elasticity of the chest wall 

 to restore normal conditions. Bring the arms above the head so as to 

 stretch the accessory muscles and to enlarge the chest still further. 

 Repeat this procedure at the rate of eighteen times in a minute (Syl- 

 vester) . 



Place the subject upon his ventral surface with a roller cushion under 

 the epigastric region. Take a position over the legs of the subject, fac- 

 ing his head. Place the palms of your hands against the posterior and 

 lateral aspect of the subject's lower ribs. Bring an even and gentle 

 pressure to bear upon this region. Release the pressure so as to allow 

 the elasticity of the chest wall to restore normal conditions. Repeat 

 this procedure at the rate of sixteen to eighteen times in a minute 

 (Schafer). What are the advantages of this method? 



Study the construction and action of the pulmotor. What are its 

 advantages and disadvantages? Contrast. 



