USES OF CAUSTICS 34*5 



in the mouth with a burning sensation and pain followed by dyspha- 

 gia and loss of tissue. The appearance of the mucosa of the mouth 

 is important in cases of poisoning, because it is an aid in the diag- 

 nosis of the nature of the irritant. Alkalies form a transparent 

 swelling of the mucosa, which is soon detached, leaving a scarlet 

 colored inflamed area beneath. Corrosives, which form a precipi- 

 tate with the tissues producfe a grayish-white, opaque stain, which 

 persists in the case of the mineral poisons. Strong acids change 

 the hemoglobin of the neighboring parts to dark acid hematin, with 

 a dark or brown stain. Nitric acid is an exception. This forms a 

 yellow stain which differs from that of picric acid by being changed 

 to an orange color by alkalies, while the picric acid stain remains 

 unchanged. 



The corrosion extends down the esophagus to the stomach and 

 intestines. Gastroenteritis is consequently produced and is shovra 

 by the usual symptoms. The vomitus and feces are more or less 

 bloody and in case of the strong acids, the vomitus is often black on 

 account of the acid hematin. This is the so-called " coffee grounds 

 vomitus." Pain is usually very severe after corrosives. Death 

 usually takes place in from 24 to 48 hours, occasionally sooner on 

 account of the shock. The temperature will be elevated if absorption 

 occurs, subnorinal, if shock or collapse is produced. 



Autopsy. Corrosion or destruction will be found particularly 

 in the upper part of the digestive tract, with alkalies, acids, etc., but 

 in the large intestines from metals. If the action has stopped short 

 of corrosion there will be hyperemia and extravasation of blood. 

 The neighboring abdominal organs may be hyperemic. 



Treatment of Poisoning. First dilute the irritant as its action 

 depends upon its concentration. Allow plenty of water or force 

 water upon the animal. If corrosion has started it is dangerous to 

 use the stomach tube on account of the liability of puncturing the 

 stomach. Administer demulcents very freely; mucilage, boiled 

 starch or preteids (white of egg, milk). Administer .the chemic 

 antidotes, alkalies for acids and acids for alkalies. Treat the pain 

 and other symptoms as they arise. 



Uses. The caustics are occasionally used for counterirritation, 

 but more often for the removal of tissue as in : 



1. Bites of venomous animals, snakes, dogs. 



2. Eemoval of pathological tissue : warts, tumors, etc. 



3. Indolent granulations. 



The most important caustics are : 



Hot iron, electricity. 



Chemic agents. 



Nitric acid on glass rod, for warts, etc. 



Trichloracetic acid, on cotton : warts, etc. 



Chromium trioxide fused on a probe. 



