Life Support: How It Works and When It’s Needed

When you hear the term “life support,” you might already have an image of what that means based on shows, movies, and news stories. But what does life support really look like? Here we will review types of life support, the reasons why a person may need it, and its possible complications.

What is life support?

Life support refers to machines or medications that keep someone alive when one or more vital organs stop working. This can happen when the heart, lungs, or brain are so severely injured that they can’t work on their own. 

If someone can’t breathe properly, they can’t get oxygen into the body, which all cells need to work. When the heart isn’t pumping well, oxygen from the lungs can’t circulate throughout the body. In cases of severe brain damage, the control centers telling the body to function can shut down. Advanced medical support will take the place of these critical organs. 

What are common reasons for life support?

Any injury or illness causing organ failure may lead to the need for life support. Sometimes this happens after a sudden illness or trauma. Other times it can happen when a chronic disease gets worse. This can occur with conditions like: 

• Sudden cardiac arrest

• Stroke

• Drug overdose or poisoning

• Heart failure

• Amyotrophic lateral sclerosis (ALS, or Lou Gehrig’s disease)

• Major trauma

• Acute respiratory distress syndrome (ARDS)

• Sepsis

• Pneumonia

• Liver failure

• Chronic obstructive pulmonary disease (COPD)

Sometimes life support is for people with serious brain injuries. It’s commonly used in any of these levels of brain injury:

• Coma: In a coma, someone looks asleep, has no awareness or consciousness, and can’t be woken up. This is usually a temporary state. The person will either get worse or recover within weeks.

• Vegetative state: Someone may look awake but has no awareness. And they have no conscious or deliberate actions. If someone is in this condition for more than 3 months, it’s called a “persistent vegetative state.”

• Brain death: This is a loss of critical brain functions necessary to live, including the reflex to breathe. In brain death, life support measures are keeping someone alive.

Read more like this

Explore these related articles, suggested for readers like you.

When Do You Need to Go to the Hospital for COVID?

How Can COVID-19 Affect the Heart?

Long COVID: Live Updates on the Latest in Research and Policy

What Are Hiccups? What Causes Them and How to Make Them Go Away

View more

What are examples of life support?

There are several types of life support. They differ in how much support is needed and which organ functions are replaced. Here is a review of common examples of life support.

Mechanical ventilation

With mechanical ventilation, someone is connected to a breathing machine (ventilator) by a tube. The person has a breathing tube in the mouth that goes into the lungs (intubation). In some cases, they may have a tracheostomy. This is a surgical procedure that places a breathing tube in the neck rather than the mouth. 

The ventilator blows air into and out of the lungs and does the work of breathing for someone. Being connected to a ventilator can be uncomfortable and distressing. People on mechanical ventilation often receive medications for sedation and pain control. 

Vasopressors

Vasopressors (“pressors”) are IV (intravenous) medications that support circulation. Some help the heart pump stronger or faster. Others help blood vessels squeeze tightly enough to keep up a normal blood pressure. Both actions are important to make sure organs and tissues get enough blood flow to work properly.

In most cases, these medications are given through central venous catheters. These are central IV lines that go into the larger blood vessels in the neck, chest, or groin. 

Common vasopressors include: 

• Phenylephrine

• Norepinephrine

• Epinephrine

• Vasopressin

• Dopamine

Cardiac assist devices

Cardiac assist devices are small machines placed in or near the heart to help it pump when it’s failing. There are several types, including a left ventricular assist device and a total artificial heart. 

This form of life support is sometimes used while a person is waiting for a heart transplant. Other times cardiac assist devices are used in the short term while the heart recovers after a major heart attack or cardiac surgery.

Extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) is useful when the heart or lungs won’t respond to other forms of life support. With ECMO, blood is taken out of the body through a catheter. It then goes into a machine that puts oxygen into the blood. The oxygenated blood is then circulated back into the body with another catheter. ECMO can support both the heart and lungs.

There are other interventions that aren’t always thought of as life support, even though they take over the function of vital organs. And, in some cases, a person would not survive without them. These other forms of life support include: 

• Dialysis: This is a common treatment for those with kidney failure. The dialysis machine takes the place of the kidneys — filtering the blood and removing extra fluid from the body. 

• Artificial nutrition: This is a way to get nutrition when someone can’t eat normally. It includes tube feedings and nutrition through the veins, like total parenteral nutrition (TPN). For some, artificial nutrition helps supplement regular food intake. For others, it completely takes the place of eating or drinking.

How long can someone be on life support?

There is no rule about how long a person can stay on life support. People getting life support may continue to use it until they either recover or their condition worsens. In some cases, it’s possible to recover after days or weeks of life support, and the person can stop the treatments. Here are some other possible scenarios:

• Someone can be so ill that life support measures aren’t enough to keep them alive during the treatments. 

• Someone needs prolonged mechanical ventilation and stays connected to a ventilator for months. 

In these cases, life support would only end if there’s a decision to stop life support and begin end-of-life care or an illness leads to death. 

Sometimes healthcare providers decide that the chance of a meaningful recovery is very low. Or family members may feel that prolonged life support does not align with the beliefs of their loved one. In these situations, there may be a joint decision to stop life-sustaining treatments. 

If you have wishes about what you would want done if you ever needed life support, you can fill out an advance directive at any time. This document lets you clearly write out your beliefs and preferences. And it can help family members make decisions for you in the event of a crisis when you can’t communicate your wishes.

Sometimes there’s no consensus on whether to continue life support. In these cases, hospital-based ethics committees and state laws can help guide decisions.

What are the risks of life support?

People on life support are at risk for different complications. For many people, the risk increases the longer they’re on life support. There are short-term risks and long-term complications associated with life support.

Complications that can arise with life support in the hospital include:

• Hospital-acquired infections (like bacteremia, pneumonia, and urinary tract infections)

• Blood clots

• Bed sores

• Delirium

• Muscle weakness

• Limb ischemia

• Ileus (the bowels don’t move properly)

Long-term effects of life support can include:

• Cognitive impairment (including memory, attention, and processing difficulty)

• Psychiatric illness (like anxiety, post-traumatic stress disorder)

• Neuromuscular weakness or loss of muscle mass

• Joint contractures

• Airway trauma (like vocal cord damage, scarring, or narrowing)

• Prolonged respiratory dysfunction

• Sexual dysfunction

In many cases, recovery is less likely the longer life support is needed.

Can someone recover after being on life support?

Yes, but it often depends on the extent of the illness or injury. Some people do not recover from life support or die due to the underlying illness or complications. 

If someone recovers and no longer needs life support, they may still have long-term complications. Rehabilitation and support from family and caregivers are important parts of recovery.

Can someone hear while on life support?

It’s hard to say for sure whether people on life support can hear their loved ones and healthcare providers. Small studies suggest it’s possible. This probably depends on the level of sedation and how severe any possible brain injury is. 

Some might recognize their name more than general phrases and terms. When someone no longer needs life support, their memory of the experience is often very incomplete or is a mix of real experiences and delusions. 

Why trust our experts?

Written by:

Mala Mandyam Sanchez, MD

Dr. Sanchez is a board-certified internal medicine physician. She went to the University of California, San Francisco, for medical school and completed both her residency and chief residency at Stanford University.

Edited by:

Karla Robinson, MD

Karla Robinson, MD, is a medical editor for GoodRx. She is a licensed, board-certified family physician with almost 20 years of experience in health through varied clinical, administrative, and educational roles.

Our editorial standards

Meet our experts