DISEASES FROM SEPTIC INFECTION OF WOUNDS 301 



membranes in the skin become pale, then cold; the eyes are fixed, the 

 pupils dilated; the pulse becomes irregular, reduced in volume; and the 

 respiration weak and irregular. The animal appears indifferent or 

 unconscious. These symptoms may disappear very rapidly or in some 

 cases go on until the animal dies without rallying in spite of any form 

 of treatment that may be tried. 



Symptoms of a very similar character, as a result of extensive 

 hemorrhage, are sometimes presented, and must not be mistaken for 

 "shock." The same may be said to occur occasionally in the dog when 

 under the influence of chloroform. It is believed that the symptoms of 

 "shock" presented are due to an irritation or concussion of the sensitive 

 nerves, producing reflex paralysis of the vasomotor center of the medulla 

 oblongata. 



The Course of the Healing Process in a Wound. 



The healing of a wound depends to such a large extent on its form, 

 condition, location, and treatment, that from a practical standpoint we 

 may generally separate the processes into, first intention, or healing by 

 primar}' union; second, healing by second intention or suppuration; 

 third, healing under a dry scab; fourth, healing under a moist scab; the 

 various processes of wound healing can be studied in works on surgery. 



Diseases Resulting from Septic Infection of Wounds. 



There are a number of conditions which appear in wounds that are 

 due to microbes or germs, producing certain irritations of the tissues 

 surrounding the wounds, especially the blood vessels and the lymphatics. 



Phlegmon. — By this we mean the inflammation of the soft tissues 

 which has a tendency to formation of pus, especially in the loose sub- 

 cutaneous connective tissue between the muscles and under the fasciae. 

 There are two forms of this condition — a circumscribed and a diffused 

 phlegmon. 



Circumscribed Phlegmon. — The symptoms are very prominent, 

 especially Avhen it is near the skin. We find in a certain circumscribed 

 region a hot, painful, very red swelling, firm and tense in the early stages, 

 but soon becoming soft, doughy, and finally fluctuating, due to the tissue 

 breaking up and forming a purulent licjuid. From the pressure of the 

 pus the skin becomes gradually thinner and thinner, until the pus finally 

 makes its exit through the skin and escapes. If, for some reason, the 

 skin is too tough, or if the pus has not been allowed to escape by means 

 of an incision, it may cause a purulent infiltration of the surrounding 

 tissues, which is very serious and ends with necrosis of the parts, espe- 



