How to Perform Rescue Breathing

Rescue breathing is blowing air from one person into the mouth or nose of another to inflate the recipient's lungs. It's often used as a compliment to chest compressions during cardiopulmonary resuscitation. But it can also be a way to help a patient whose heart is still beating and just doesn't happen to be breathing.

What Should Happen

When we breathe naturally, we expand the size of our chests by pushing the diaphragm down and contracting the muscles around the rib cage. Our chests get bigger, creating negative pressure inside and air rushes in, filling the lungs. It's like an accordion; pull it apart and air rushes into it.

The negative pressure also encourages blood to return to the chest. Breathing is good and helps not only get oxygen into the bloodstream, but it also helps remove carbon dioxide and encourage blood flow.

The Bad News

Rescue breathing, by pushing air in, actually inhibits blood returning to the heart. Rescue breathing is important for patients who are not breathing but still have a heartbeat. In most cases, rescue breathing is only recommended to be performed by lay rescuers in certain cases.

1
Tilt the Head

Man tilting the head of a cpr dummy back
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Lay the patient flat on his back and tilt his head back. Place one hand on his forehead and use your other hand to lift his chin.

By tilting the patient's head back, you're straightening out the trachea (also known as the "windpipe") and opening it up for more airflow. If there is anything blocking airflow in the trachea, such as the back of the tongue or fluid that collects in the windpipe, this should help alleviate the blockage.

2
Cover the Mouth and Breathe

College student performing CPR on mannequin in class
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Cover the patient's mouth with your mouth. Make a seal and blow just enough air to make the patient's chest rise.

By blowing gently, you're filling the patient's lungs with your own exhaled air. The air you exhale isn't perfect, but it does have enough oxygen to help someone live.

Don't blow too hard. If you do, the air might not all go into the trachea. Some air will go past the trachea and through the esophagus, filling the stomach. Too much air in the stomach can lead to the patient vomiting, even if she's unconscious.

3
Repeat

man giving woman mouth to mouth
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If you're performing CPR, do a second breath and then push on the chest 30 times.

If you're giving mouth to mouth to a patient who is not in cardiac arrest (his heart is still beating), then just keep giving rescue breaths until someone else arrives to help you. If you didn't call 911, go ahead and do it now.

By adding rescue breaths to your CPR treatment, you are possibly increasing the patient's chance of survival. There isn't any definitive research on the benefits of mouth to mouth, but plenty of anecdotes suggest that rescue breathing helps save lives.