206 SURGICAL DISEASES 



commonly used, includes only such injuries that are accompanied 

 hj breaks or divisions of the skin and mucous membrane. It is 

 usually an open, hemorrhagic injury. 



If the tissues are severed by a sharp instrument and the 

 edges of the wound are smooth, it is classed as an incised or 

 clean-cut wound. This class is not commonly met with in do- 

 mestic animals outside of operative wounds. 



When the tissues are torn irregularly, the injury is classed 

 as a lacerated wound. A barb-wire cut is the best exam23le of 

 this class. 



A contused wound, is an injury caused by a blunt object. 

 Such injuries may be divided into superficial and deep. Super- 

 ficial-contused wounds may be an abrasion to the skin or mucous 

 surface. Deep-contused wounds may be followed by loss of 

 tissue or sloughing, and may present irregular, swollen margins. 

 Such injuries are commonly caused by kicks. 



Punctured wcuvds are many times deeper than the width 

 of the opening or break in the skin or mucous membrane. This 

 class is produced by sharp objects, such as nails, splinters of 

 wood, and forks. 



Sometimes, wounds are given special names, as gun-shot, 

 poisoned, and open joint, depending on the nature of the cause 

 and region involved. 



Bleeding or hemorrhage is the most constant s_\Tnptom. 

 The degree of hemorrhage depends on the kind, number and 

 size of the blood-vessels severed. In arterial hemorrhage, the 

 blood is bright red and spurts from the mouth of the cut vessel. 

 In venous hemorrhage, the blood is darker and flows in a con- 

 tinuous stream. In abrasions and superficial wounds capillary 

 hemorrhage occurs. Death may follow severe hemorrhage. 

 Weak pulse, general weakness, vertigo, loss of consciousness and 

 death may result if one-third of the total quantity of blood is 

 lost. Unthriftiness and general debility may follow the loss of 

 a less quantity of blood. 



