Char burn is a term for fourth-degree burns.

Full-thickness burn is a term for third-degree burns.

Second-degree burns are also known as partial thickness burns.

Superficial burn is a term for first-degree burns.

Hypoglycemia means low blood sugar. Signs of hypoglycemia include sweating, feeling tired, dizziness, feeling hungry, a fast or pounding heartbeat, a staggering gait, and confusion.

If acid or another chemical touches your skin, you should rinse it off with water immediately.

First-degree burns are the least serious type of burn because they only damage the epidermis (the outer layer of the skin). Second-degree burns are more serious because they damage two layers of the skin: the epidermis and dermis. Third-degree burns are the most dangerous because they destroy the epidermis and the dermis.

The rule of nines is a rapid method to estimate the percentage of the body's surface area affected by burns. It divides the body into sections, allowing for a quick estimation of the extent of burn injury. In adults, the surface area is allocated as follows:

• Left arm: 9%
• Right arm: 9%
• Head and neck: 9%
• Chest: 9%
• Abdomen: 9%
• Upper back: 9%
• Lower back: 9%
• Left leg: 18%
• Right leg: 18%
• Genitals: 1%

First-degree burns only affect the outer layer of skin (epidermis). The damage is only superficial and can be treated with cool water and moisturizer. Second-degree burns affect the epidermis and part of the dermis (deeper skin layer). These burns are blistered, swollen, and very painful. Third-degree burns destroy the epidermis and dermis and extend to the subcutaneous (fat) layer. Fourth-degree burns extend through skin, fat, muscle, and possibly bone. The risk of death is high, and immediate medical help is needed.

The first thing you should do is call 911. By calling 911 first, you ensure trained professionals are on the way. Also, the 911 dispatcher can guide you through the process of performing CPR while you wait for the ambulance to arrive.

The acronym FAST helps to remember the symptoms of a stroke:

• F = Facial drooping
• A = Arm weakness
• S = Speech difficulties
• T = Time

Mouth-to-mouth breaths are for someone who has stopped breathing, not someone who is having a seizure.

Holding down a person having a seizure is dangerous as you could injure them.

Putting something soft under their head will help protect their head from bumps.

Putting something wooden in into the mouth of someone having a seizure is dangerous because it can injure their teeth or jaw.

In first aid, ABC stands for Airway, Breathing, and Circulation.

• Airway: Ensure the airway is open
• Breathing: Check the patient is breathing
• Circulation: Assess the patient's circulation. If necessary, begin CPR (chest compressions and rescue breaths).

When performing CPR, give 30 chest compressions followed by 2 rescue breaths.

If acid spills on the body, rinse the area with water immediately to wash off the acid. If a large area is affected, use the emergency safety shower.

The first step to treat a wound with significant bleeding is to apply pressure to the wound. This is done by placing a clean cloth or sterile gauze on the wound and applying firm pressure with the hand. The pressure helps to stop the bleeding by allowing the blood to clot. Maintain pressure on the wound for several minutes or until the bleeding stops.

If someone has frostbite due to liquid nitrogen, you should immerse the affected area in tepid water and then seek medical attention. Do not use water hotter than 44°C. Never rub the affected area or apply any form of direct heat, as this could damage tissues.

If you suspect someone has a head, neck, or back injury, you must keep the person still until emergency medical care arrives. Any movement could result in spinal cord damage, leading to paralysis or even death.

Someone with a noseblood should sit up straight and tip their head slightly forward. They should not tilt their head back, as this could cause blood to run down the throat and they may swallow it.

Hyperpyrexia is the term for exceptionally high fever.

Hyperthermia is an abnormally high body temperature.

Hypothermia is a body temperature below 35°C. The term comes from hypo (meaning "below") and thermia (meaning "heat").

Hypoxia is low levels of oxygen in the body.

When someone is bleeding, applying a tourniquet should be a last resort. This is because tourniquets can permanently damage nerves, muscles, and blood vessels, and even result in the loss of the extremity. Therefore, tourniquets should only be used as a last resort when all other methods of controlling the bleeding have failed. Furthermore, tourniquets should never be applied to a joint. Placing a tourniquet over a joint can reduce its effectiveness in stopping bleeding. It can also cause nerve, bone, and tissue damage.

Anaphylactic shock is a severe, potentially life-threatening allergic reaction.

Cardiogenic shock is a condition where the heart cannot pump enough blood for the body's needs.

Hypovolemic shock is a condition caused by severe blood loss.

Septic shock is a condition where blood pressure becomes dangerously low after an infection.

The sooner the person is seen by paramedics and gets to the emergency room, the better the chance of survival. This is why it is important to call 911 as quickly as possible.

In CPR, the recommended chest compression depth for adults is 5–6 cm (2 to 2.4 inches).

The Heimlich maneuver is an emergency procedure for upper airway obstructions (choking). By exerting pressure on the bottom of the diaphragm, the lungs are forced to expel air, dislodging the obstruction.

If you suspect someone has received an electric shock, you must ensure they are no longer in contact with the electrical current before you can treat them. If it is possible to do so safely, turn off the source of electricity. DO NOT touch the casualty if you have been unable to isolate them from the source of the electrical shock or turn off the electricity, or you will receive a shock yourself.

The recovery position is for people who are unconscious but still breathing. The position keeps their airway open and prevents choking. The other options (breathing abnormally, cardiac arrest, and unconscious and not breathing) require CPR instead.

For chest compressions in CPR, the hands should be placed in the center of the chest. This location ensures effective compression of the heart to restore blood flow.

The chain of survival is a series of actions that, when performed in order, increase the likelihood of survival from cardiac arrest.

The “chain of survival” is the sequence of events that maximizes the chances of survival from cardiac arrest. The correct sequence is:

1. Call 911 to get emergency services on their way
2. Start CPR to maintain circulation and oxygenation
3. Use defibrillation to restore a normal heart rhythm

Adrenaline (epinephrine) is the first treatment for severe allergic reactions (anaphylaxis). It is available in a pre-loaded injection device known as an adrenaline auto-injector. Adrenaline acts quickly to open up the airways, reduce their swelling, and raise blood pressure.

Ischemic stroke is caused by a blood clot blocking a blood vessel in the brain. This prevents brain tissue from getting oxygen and nutrients, and brain cells begin to die within minutes.

An open fracture is where the broken bone can be seen through the skin. If the bone breaks in a way that bone fragments stick out through the skin, or a wound penetrates down to the broken bone, the fracture is called an open fracture.

Transverse fractures have horizontal fracture lines.

Hypovolemic shock is a critical condition caused by a sudden drop in blood flow through the body.

Septic shock is a serious form of sepsis, a condition when the body’s immune system has an extreme response to an infection, causing damage to its own tissues and organs.

Chest compressions should be delivered at a rate of 100 to 120 per minute, or around two compressions per second.

Atonic seizures cause all the muscles to suddenly relax.

Clonic seizures involve rhythmic twitching or jerking of one or several muscles.

Myoclonic seizures involve only one or a few twitches or jerks without any particular rhythm.

Tonic seizures involve sudden stiffening and contraction of the muscles.