Abdominal Thrusts

See Heimlich manoeuvre.

Absence Seizures

Absence seizures are experienced as short, sudden lapses of consciousness. They’re more common in children than in adults. Also known as petit mal seizures.

Acetylsalicylic Acid (ASA)

Also known as aspirin. A common drug for relieving minor aches, pains, and fevers. Aspirin is also commonly used to treat heart attacks because of its blood-thinning properties. A person experiencing a heart attack will often take two 81mg low dose aspirin while waiting for Emergency Medical Services (EMS) to arrive.

Advanced Life Support (ALS)

Life-saving techniques and skills that go beyond basic life support.

Agonal Breathing

A medical term used to describe gasping or struggling to breathe. It’s often a symptom of a severe medical emergency like Sudden Cardiac Arrest or stroke and is not proper breathing but rather a reflex from our brainstem.


An antigen, capable of triggering an allergic reaction.


An overstimulation of inflammatory reactions that happens in response to a specific environmental stimulus or allergen, referred to as an antigen (see antigen).


A severe, possibly life-threatening allergic reaction.


A weakening and bulging of an artery wall.

Angina (Angina Pectoris)

Severe chest pain that happens when there’s not enough blood going to your heart. It is typically caused by atherosclerosis, but can also be caused by being in cold temperatures, playing sports, or other physical activity. It can be a sign of something more serious, like heart disease.


A substance (e.g., shellfish, nuts, venom from a bee sting, latex) that triggers the body’s antibodies, resulting in an immune response.


A loss of ability to understand or express speech and the ability to read or write because of an injury to the brain. It’s most commonly caused by a stroke.


A disturbance in the electrical system of the heart that makes the heart beat in an irregular way.

Arteriovenous Malformation (AVM)

An abnormal connection of blood vessels in the brain.


A type of blood vessel. Arteries deliver oxygen-rich blood from our heart to the tissues of our body. (See Vein)


Suffocation; being deprived of oxygen, which can result in unconsciousness or death.


The buildup of fats, cholesterol, and other substances like plaque in and on the artery walls that can restrict blood flow.

Automated External Defibrillator (AED)

An easy-to-use medical device that can analyze the heart’s rhythm and, if necessary, deliver an electrical shock (defibrillation) to help the heart re-establish an effective rhythm. It’s used to help those experiencing Sudden Cardiac Arrest.

Barrier Device

A device, such as a mask, that protects you from the possible transfer of infectious disease when performing rescue breathing (mouth-to-mouth) during CPR.


A class of drugs used to treat a range of conditions, including anxiety and insomnia.