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First aid
First aid is the emergency(紧急)care for a victim’s(受害人)sudden illness or injury until more skillful medical treatment is available．First aid may save a life or improve certain vital(生命攸关的)signs including pulse temperature an unobstructed airway and breathing．In minor emergencies first aid may prevent a victim’s condition from worsening and provide relief(解除)from pain．First aid must be carried out as quickly as possible．In the case of the seriously injured a few minutes can make a difference between a complete recovery and the loss of life．
First-aid measures depend upon a victim’s needs and the provider’s level of knowledge and skills．Knowing what not to do in an emergency is as important as knowing what to do．Improperly moving a person with a neck injury for example can lead to the everlasting spinal injury and paralysis(永久性脊髓伤害和瘫痪)．
Despite the variety of injuries possible several principles of first aid can be used for all emergencies．The first step is to call for the professional medical help．The victim if conscious(有知觉的) should be reassured that medical aid has been requested and asked for permission to provide any first aid．Next assess(估计)the scene asking other people or the injured person’s family or friends about details of the injury or illness any care that may have already been given and preexisting conditions(原先就存在的疾病)such as diabetes(糖尿病)or heart trouble．Unless the accident scene becomes unsafe or the victim may suffer further injury do not move the victim．
First aid requires rapid assessment(估计)of victims to determine whether life threatening conditions exist．One method for evaluating(估计)a victim’s condition is known by the acronym(只取首字母缩写词)ABC which stands for：
A－Airway：Is it open and unobstructed?
B－Breathing：Is the person breathing? Look listen and feel for breathing．
C－Circulation：Is there a pulse? Is the person bleeding externally(体表上)?Check the skin color and temperature for the additional indications of circulation problems．
Once the obvious injuries have been evaluated the injured person’s head should be kept in a neutral position in line with the body．If no evidence exists to suggest the potential skull(头骨)or spinal injury place the injured person in a comfortable position．Positioned on one side a victim can throw up without choking(窒息)or obstructing the airway．