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Emergency First Aid Priorities


Amy H. Kaji

, MD, PhD, Harbor-UCLA Medical Center, David Geffen School of Medicine

Last full review/revision Jun 2020| Content last modified Jun 2020

The first priority during a medical emergency is to save lives. A person who is unconscious and unresponsive may be close to death, and rescuers must assess the situation and begin treatment as needed to restore and maintain the person's airway, breathing, and circulation (the ABCs). A problem in any of these areas may be fatal if not corrected quickly. The airway, which is the passage through which air travels to the lungs, can become blocked (for example, by choking on or inhaling a piece of food). Many disorders, such as emphysema and asthma, can make breathing difficult. Circulation of blood, which depends on a pumping and beating heart muscle, can stop during cardiac arrest. As needed, rescuers should immediately begin

  • Maneuvers to relieve choking (for example, abdominal thrusts, also called the Heimlich maneuver)
  • Cardiopulmonary resuscitation (CPR) for people in cardiac arrest

The next priority is to get medical assistance by calling for emergency medical care. In the United States, emergency medical care can be accessed by calling 911. The caller should give the dispatcher a full description of the person's condition and how the injury or illness developed. The caller should not hang up until told to do so. If several lay people (rescuers) are present, one should call for help while another begins assessment and first aid.

After calling 911 or the local emergency service, rescuers, when necessary, can also give people:

  • Epinephrine, by intramuscular injection, for severe allergic reactions (anaphylaxis), such as after a bee sting
  • Naloxone, in the nose or by intramuscular injection, if a person stops or nearly stops breathing after an opioid drug overdose

If many people are injured, the most seriously injured person should be treated first. Assessment should take less than 1 minute per injured person. In each case, the rescuer should consider whether the situation is

  • Life threatening
  • Urgent but not life threatening
  • Not urgent

Determining who is in most urgent need of treatment may be difficult, because someone screaming in pain may be less seriously injured than someone who cannot breathe or who is in a coma and, therefore, is quiet. Difficulty breathing and massive bleeding are life threatening, but a broken hand or foot can almost always wait for treatment, no matter how painful.

When there are many people with serious injuries and resources are limited, rescuers may need to provide treatment only to those people who rescuers believe have a chance of surviving.

When injured people are unable to convey medical information because they are confused or unconscious or because of the severity of their condition, the information should be obtained in other ways. For example, if an unconscious person is found near an empty bottle of pills, the bottle should be given to the emergency medical personnel. A description of how a person became injured and other information from bystanders, family members, or rescuers can be essential to the person's treatment.

People who do not need urgent treatment are provided reassurance and simple measures, such as supplying a blanket and keeping the person calm and warm, while they wait to be treated.

To prevent the spread of blood-borne infections, rescuers should protect themselves following universal precautions, an infection control concept that regards all human blood and body fluids as if they were known to be infectious. For example, serious diseases, such as human immunodeficiency virus (HIV) infection and hepatitis B and hepatitis C (see Overview of Hepatitis), can be transmitted through blood and certain body fluids. If possible, rescuers should wear latex or nitrile examination gloves for the best protection. If gloves are not available, plastic can be used. For example, rescuers can place their hands inside plastic food storage bags or anything waterproof. Face masks and safety glasses (or face shields) and protective gowns and caps also should be worn if splashing of fluids or blood may occur.

If contaminated, the hands—including the area under the fingernails—should be washed vigorously with soap and water or a mild solution of bleach (about 1 tablespoon of bleach per quart of water, or about 15 milliliters of bleach per liter of water) as soon as possible. If neither is readily available, an alcohol-based hand sanitizer can be used.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Epinephrine ADRENALIN
Naloxone EVZIO

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