Critical care is medical care for people who have life-threatening injuries and illnesses. It usually takes place in an intensive care unit (ICU). A team of specially-trained health care providers gives you 24-hour care. This includes using machines to constantly monitor your vital signs. It also usually involves giving you specialized treatments.

You need critical care if you have a life-threatening illness or injury, such as:

• Severe burns
• COVID-19
• Heart attack
• Heart failure
• Kidney failure
• People recovering from certain major surgeries
• Respiratory failure
• Sepsis
• Severe bleeding
• Serious infections
• Serious injuries, such as from car crashes, falls, and shootings
• Shock
• Stroke

In a critical care unit, health care providers use lots of different equipment, including:

• Catheters, flexible tubes used to get fluids into the body or to drain fluids from the body
• Dialysis machines ("artificial kidneys") for people with kidney failure
• Feeding tubes, which give you nutritional support
• Intravenous (IV) tubes to give you fluids and medicines
• Machines which check your vital signs and display them on monitors
• Oxygen therapy to give you extra oxygen to breathe in
• Tracheostomy tubes, which are breathing tubes. The tube is placed in a surgically made hole that goes through the front of the neck and into the windpipe.
• Ventilators (breathing machines), which move air in and out of your lungs. This is for people who have respiratory failure.

These machines can help keep you alive, but many of them can also raise your risk of infection.

Sometimes people in a critical care unit are not able to communicate. It's important that you have an advance directive in place. This can help your health care providers and family members make important decisions, including end-of-life decisions, if you are not able to make them.