ULCERATION. GANGRENE. BED-SORES. 



Causes : inflammation, exudation, obstructed circulation, lesions in 

 trophic nerve centres, sclerosis, toxins, ergot, caustics, freezing, gangrene, 

 microbes, cryptogams, spoiled fodder, white skins, buckwheat, insolation. 

 Symptoms : inflammation, molecular disintegration, dry sloughs. Treat- 

 ment : camphorated spirit or vaseline, antiseptics, phenol, salicylic acid, 

 iodoform, iodine, creolin, lysol, tar, detach sloughs. 



In all cases in which the skin is violently inflamed, and particu- 

 larly when the .seat of an abundant exudation or infiltration which 

 blocks circulation and retards nutrition, the tissues are especially 

 liable to death, molecular or by sloughing, and formation of bed- 

 sores. As a general cause lesions of the trophic centres in the 

 medulla and cord must be accepted as a cause of the imperfect 

 nutrition and lack of vitality. This is seen in sclerosis of the 

 cord, but may appear as the result of poisoning of the 

 myelon as well as tlie gangrenous tissues by absorbed toxins. 

 Again a common cause of circumscribed cutaneous gangrene is 

 the capillary contraction and obstruction of ergotism. This 

 usually involves all the tissues, soft and hard, at the distal end of 

 a member or organ, causing the separation of all at one common 

 level, but in less severe forms the skin only sloughs, in the form 

 of round or irregular masses, usually around the coronet, and the 

 resulting sores heal up under an appropriate diet. Cauterization 

 and freezing may be a further occasion of gangrene. Finally, the 

 local operation of the microbes of gdngrene, determines both 

 ulceration and sloughing. Cryptogams on spoiled fodders 

 (trefoil, lupins, vetches, rusty gramineae) are also charged with 

 developing gangrene. 



White skins or white patches on the skin are especially liable 

 to suffer as in cases of fagopyrism and " grease ". The action of 

 the solar rays in summer must therefore be accepted as a con- 

 current cause. 



Symptoms. The first symptoms are usually those of cutaneous 

 congestion or inflannnation. Redness, swelling, pitting on pres- 

 sure, or tension, are accompanied or followed by vesicles, chaps 

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