326 FIRST AID TO THE INJURED 



age, that the edges of the cut may be held close together. 

 If a large artery has been cut, there should be imme- 

 diately applied an elastic or other tight bandage be- 

 tween the wound and the heart at one or another of 

 the points where the artery can be compressed (see 

 p. 162). Unless it is certain that a wound is super- 

 ficial, a physician should be called at once, since there 

 may be internal bleeding of greater or less seriousness. 



To prevent infection, it is necessary to get rid of the 

 microbes lying upon the skin in the neighborhood of the 

 wound. This is best accomplished by thoroughly scrub- 

 bing the skin with a clean brush and soap and then 

 applying a disinfectant solution (see Appendix C). 

 The person who bandages the wound should first have 

 his hands similarly cleansed. 



Bruises. Bruises differ from wounds in that the 

 skin is not broken. A combination of a broken skin 

 and a bruise is called a contused wound. A bruise in- 

 volves the crushing of tissues and blood-vessels with 

 more or less internal bleeding. This usually works to 

 the surface in a few hours and produces the dark color 

 characteristic of a bruise. This changes to blue and 

 gradually to yellow, as the pigment of the blood is 

 absorbed. 



Treatment: To prevent blood and lymph from col- 

 lecting in the injured tissues and causing a swelling 

 which retards healing, the bruised part should be imme- 

 diately bound up tightly with a compress and bandage 

 (see Appendix C). 1 Hot water or ice may be used 

 as a partial substitute for the bandaging, since cold 

 and especially heat cause contraction of the blood-vessels 

 and thereby check bleeding. Gentle rubbing is also 



1 Care should be taken not to bind so tightly as to check the flow 

 of blood in arteries and veins. 



