ANESTHESIA 337 



The mortality is 1 in 8,162 chlorof ormizations ; and 1 in 16,302 etherizations 

 in over a million cases in human practice (Hewitt). Chloroform is 3% times 

 more depressant to nerve centres, 8 times more depressant to the heart, and 

 causes 6 times more deaths, than ether. 



It will be seen that all the advantages are in favor of chloroform, 

 except that of safety. Ether is more expensive than chloroform^ but 

 cheaper than a funeral. 



Accidents and Dangers Attending Anesthesia. 



Respiratory failure and asphyxia may occur from giving too much 

 of the anesthetic, and from mechanical obstruction in the air passages. 

 The tongue may fall back upon the epiglottis and prevent the free en- 

 trance of air. The latter accident is obviated by pulling the tongue for- 

 ward with the hand, or, in the case of the smaller animals, by means of 

 forceps, or suture passed through the tongue. Mucus, blood or vomitus 

 may obstruct the mouth, pharynx, larynx, or trachea, and should be re- 

 moved if possible by swabbing with absorbent cotton. To prevent exr 

 cessive secretion of mucus in the air passages atropine may be given sub- 

 cutaneously fifteen minutes before etherization. The head should be ex- 

 tended and the lower jaw of the patient held forward during anesthesia, 

 and no impediment to the free movement of the chest is allowable. 

 Struggling is to be avoided, as far as possible, since it leads to irregular 

 respiration and asphyxia, and causes the anesthetizer to push the inhala-f 

 tion, strains the heart, and favors cardiac dilatation with chloroform. 

 Struggling may be prevented to some extent by giving the anesthetic 

 well diluted Ivith air at the outset. Asphyxia results also from tetanic 

 fixation, or relaxation of the respiratory muscles. The signs of asphyxia 

 include cyanotic mucous membranes, muscular twitchings, shallow, feeble, 

 slow and irregular breathkig, with long intervals between the respiratory 

 movements, and dilation of the pupils. If death occurs, the heart con- 

 tinues to beat after the breathing stops. The condition of the diaphragm 

 during etherization is an important guide. At first the contractions of 

 the diaphragm are so vigorous that the viscera are forced backward, and 

 the abdominal wall bulges outward during inspiration. As the inhalation 

 is prolonged the diaphragm becomes flaccid and powerless, the respira- 

 tory movements are shallow, and the breathing thoracic. The abdomi- 

 nal contents may then be drawn forward during inspiration into the. 

 thoracic cavity, so that the abdomen is retracted (Hare). When the 

 latter condition is seen, etherization should be stopped instantly. 



Heart failure occurs more frequently with chloroform, but does oc- 

 casionally result from the action of ether upon animals with a fatty or 

 otherwise weak heart. Cardiac depression is shown by a weak, irregu- 

 lar and rapid pulse, and pallor of the mucous membranes. Respiration 

 begins to fail before the heart stops in chloroform. Artificial respira- 

 tion will therefore usually prevent death. The real cause of death, is, 

 however, vasomotor paralysis in chloroformization. Operations should 

 never be done under chloroform before the patient is fully under the 

 influence of the anesthetic, as irritation of a sensory nerve caused by 



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