CHAPTER XII 



WOUNDS AND WOUND INFECTIONS 

 SYMPTOMS, TREATMENT, AND HEALING OF WOUNDS 



A wound is any break in the continuity of the skin or mucous 

 membrane. More or less destruction of tissue always occurs 

 as the result of a wound. 



The kinds of wounds usually recognized are : ( 1) incised wounds, 

 with clean-cut margins; (2) lacerated wounds, with flaplike tears; 

 (3) punctured wounds, with small, round openings; (4) contused 

 wounds, with the tissues bruised from contact with a blunt 

 instrument. The size of a wound is no guide to the prognosis, 

 which should depend in large measure on the situation of the 

 wound and the nature of the injured vessels. Minor wounds 

 are just as likely to lead to complications as are extensive ones. 



The symptoms of wounds are hemorrhage, pain, gaping, and 

 disturbed function. 



Hemorrhage is the escape of blood from the vessels in which it 

 is normally contained. It varies according to the size and kind 

 of the wounded blood-vessel, but is most pronounced in incised 

 wounds. When an artery is injured, the blood is bright red in 

 color and spurts out with each heart-beat. An injured vein 

 allows blood of dark-red color to escape — it flows steadily from 

 the wound and upon exposure to the air turns lighter red. Capil- 

 lary hemorrhage is intermediate in color and oozes. If hemor- 

 rhage is into the body cavities, the blood is rapidly and entirely 

 absorbed. From the tissues absorption is slower, and a "black- 

 and-blue spot" or "blood blister" (hematoma) remains for some 

 time to mark the location. Where over one-third of the total 

 volume of blood is lost, the pressure falls and death may follow. 

 After excessive loss of blood the visible mucous membranes 

 become very pale, the animal gets dizzy, loses consciousness, 

 and goes into convulsions. There is a rapid re-establishment in 

 the quantity of the blood following hemorrhage by absorption 

 of fluids from the tissues and intestines. The solid constituents 



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