- ACTION OF ETHER 331 



mucous membrane of the digestive tract, and should be given only when 

 considerably diluted with water. Ether stimulates secretion, motion, 

 and increases local blood supply of the stomach. Ether, in concentra- 

 tion, resembles alcohol and ammonia in stimulating the heart reflexly, 

 by its irritant action upon the alimentary canal, before it has time to be 

 absorbed. It relieves pain and spasm in the digestive tract by coordi- 

 nating or restoring nervous control over the stomach and bowels. 



Circulation. — Ether is reflexly a stimulant to the heart and vasomo- 

 tor centres through peripheral irritation of its vapor, as in the case of 

 alcohol. Some authorities allow no direct stimulating action (Cushny). 

 In poisonous doses, or after prolonged inhalation, the circulation becomes 

 weak and the heart stops beating from direct depression of its muscle. 



Nervous System. — Ether is chiefly depressant to nerve centres. Its 

 apparent primary stimulation of the central nervous system is some- 

 what doubtful and many experimenters deny that it directly stimulates 

 the nerve centres at all. Ether depresses and abolishes the functions 

 of all the great nerve centres in the following order, and with the follow- 

 ing results: 



1. The cerebrum (with loss of consciousness). 



2. Sensory spinal tract (loss of sensation). 



3. Motor spinal area (loss of motion and partial loss of reflex 

 action) . 



4. Sensory medullary centres. 



6. Motor medullary centjres (failure of respiration). 



Ether does not affect the nerves or muscles when inhaled or in- 

 gested. Ether depresses the action of the nerves, however, when applied 

 locally. 



Respiration. — The respiratory centre is stimulated by inhalation ox 

 ingestion of therapeutic quantities of ether. Paralysis of the respiratory 

 centre occurs in the last stage of ether poisoning. Ether vapor is irri- 

 tant to the respiratory mucous membrane, and causes coughing and chok- 

 ing during inhalation. It is not an appropriate anesthetic, therefore, 

 in inflammatory conditions of the respiratQry tract, because its vapor is 

 given in greater concentration than in chloroform. In giving ether by 

 the drop method undue irritation of the lungs is avoided and such condi- 

 tions as bronchitis, pulmonary edema and pneumonia. Ether vapor excites 

 the peripheral ends of the trifacial nerve in the face, and the vagus nerve 

 in the lungs, so the temporary arrest of respiration often occurs when a 

 fresh supply of ether is added during inhalation. 



Temperature.— The temperature of the body may be raised during 

 the stage of excitement and struggling, but prolonged etherization leads 

 toi loss of heat, owing to evaporation of ether from the lungs, and gen- 

 eral depression of the nervous system. 



Elimination. — Ether is eliminated principally from the lungs." Re- 

 cent experiments indicate that ether causes contraction of the renal ar- 

 teries, with diminution in the size of the kidneys, suppression of urine 

 and albuminuria. Ether leads to fatty degeneration of the kidneys, 

 liver and heart, less frequently than chloroform, however. 



Acetone has been found in the urine of 90% of patients in human 



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