What to Know About Agonal Breathing

Medically Reviewed by James Beckerman, MD, FACC on September 04, 2023
4 min read

Agonal breathing is when someone who is not getting enough oxygen is gasping for air. It is usually due to cardiac arrest or stroke. It's not true breathing. It's a natural reflex that happens when your brain is not getting the oxygen it needs to survive. 

Agonal breathing is a sign that a person is near death. It's also a sign that the brain is still alive. People who have agonal breathing and are given cardiopulmonary resuscitation (CPR) are more likely to survive cardiac arrest than people without agonal breathing.

Agonal breathing can be caused by anything that cuts off the blood supply to the brain. Your brain gets oxygen from the cells in your blood. Agonal breathing is most likely to occur in the following situations.

Cardiac arrest. Cardiac arrest is the most common reason for agonal breathing. It's different from a heart attack, although they can be related. A heart attack happens when blood is blocked from reaching part of your heart by a clogged artery. The part of the heart that gets blood from the blocked artery starts to die. 

Heart attack symptoms don't usually come on suddenly. They build up over hours, days, or even weeks. But they can happen suddenly and be intense. Your heart doesn't stop beating during a heart attack.

Cardiac arrest typically occurs without any warning. It is caused by an electrical problem in your heart. This disrupts its pumping rhythm. Your heart is not able to pump blood to your organs. This will cause you to lose consciousness and die within minutes without treatment.

You are at greater risk of cardiac arrest if you've had a heart attack. Heart attacks can cause cardiac arrest, although most don't. Other heart conditions can also lead to cardiac arrest, including:

Ischemic stroke. This type of stroke happens when an artery that carries blood to your brain is blocked. This is the most common type of stroke. About 87% of strokes are ischemic strokes.

Anoxic brain injury. This is any type of injury that prevents blood from getting to your brain. Cardiac arrest and ischemic strokes are types of anoxic brain injuries. Other common causes include:

People who have seen agonal breathing describe it as:

  • Barely breathing
  • Occasionally breathing
  • Problem breathing
  • Irregular breathing
  • Heavy breathing
  • Labored breathing
  • Sighing
  • Noisy breathing
  • Gurgling
  • Moaning
  • Groaning
  • Snorting

The first thing you should do if you witness someone experiencing agonal breathing is to call emergency services. The type of first aid needed will depend on what is causing the agonal breathing.  

Cardiac arrest. Tell the dispatcher about the abnormal breathing. People often mistake agonal breathing as a sign that the person is breathing okay and doesn't need CPR. This is especially bad. The person has a good chance of surviving if CPR is started while they have agonal breathing. 

Start hands-only CPR if you believe someone is having a cardiac arrest. There are only 2 steps to hands-only CPR. First, call 911 or have someone else do it. Second, push hard and fast in the center of the chest. Push to the beat of a song that has 100 to 120 beats per minute, such as "Staying Alive" by the Bee Gees.

You don't need to check for breathing or do mouth-to-mouth breathing. Mouth-to-mouth breathing can make the situation worse when someone is having a cardiac arrest and having agonal breathing.

Hands-only CPR is appropriate when you see a teen or adult suddenly collapse. But traditional CPR should be performed on:

  • All infants.
  • All children until puberty.
  • Anyone already unresponsive and not breathing normally.
  • Cases of drowning, drug overdose, breathing problems, or prolonged cardiac arrest.

Choking. Perform the Heimlich maneuver or the 5-and-5 approach if someone is choking. The 5-and-5 approach involves alternating 5 back blows with 5 abdominal thrusts until the object causing the choking is dislodged. This should only be done if the person cannot talk, cry, or laugh forcefully.

Drowning. Call 911 if someone has agonal breathing due to a near-drowning event. Begin CPR, starting with 2 rescue breaths, and then continue with traditional CPR. People who receive chest compressions after nearly drowning are likely to vomit. Turn them on their side and clear their airway with your fingers or a cloth if this happens.