First Aid Emergency Preparedness Print How to Perform Rescue Breathing Knowing when to use it is the first step By Rod Brouhard, EMT-P Updated August 14, 2019 Medically reviewed by a board-certified physician More in First Aid Emergency Preparedness Allergies & Anaphylaxis Bites & Stings Breathing Emergencies Broken Bones Bruises, Cuts & Punctures Heat & Cold Exposure Infections Rash Calling for Help View All Rescue breathing (previously known as mouth-to-mouth resuscitation) is a life-saving intervention in which you blow air into a person's mouth when they stop breathing. It is often used with chest compressions during cardiopulmonary resuscitation (CPR) but can also be used on its own if the person's heart is still beating. Situations in which rescue breathing may be used include: Choking accidentsNear-drowningDrug overdosePoisoningCarbon monoxide poisoningSevere asthma attack AHA Recommendations Rescue breathing is something only certified rescuers should perform in cases of cardiac arrest. This is because, by expanding the chest artificially, rescue breathing can inhibit the blood flow to the heart. Professionals certified in CPR are trained to ensure this doesn't undermine the effectiveness of chest compression or the survival of person being treated. In cases of cardiac arrest, the American Heart Association (AHA) recommends chest compressions without rescue breathing if you are untrained or unable to competently perform professional CPR. On the other hand, if a person still has a pulse but is breathing abnormally, rescue breathing may help keep them alive until emergency help arrives. Here is a step-by-step guide on how to correctly perform rescue breathing in an emergency situation: 1 Preparation Madrolly / Getty Images If confronted with a person who is not breathing, start by laying them flat on their back.Call 911 or have someone else call 911 while you proceed with rescue breathing.Check the person's pulse. If there is a heartbeat, you can proceed with rescue breathing. If not, you would need to start with chest compressions with or without rescue breathing.Place one hand on the person's forehead and use your other hand to lift the chin. Tilting the chin straightens the trachea (windpipe), providing a straight passage from the mouth to the lungs.Check for breathing. Listen carefully but for no longer than 10 seconds. If there are no signs of respiration, start rescue breathing. If you hear crackling or strangulated sounds, they may be choking.Finally, check to see if there anything blocking the trachea, including vomit, food, or the back of the person's tongue. If there is, reach in with your fingers and clear it out. Never start rescue breathing until you are sure the airways are clear of debris and other obstructions. Why the CPR Guidelines Changed 2 Rescue Breathing Peter Muller / Getty Images Once you are sure that the airway is clear, pinch the person's nostrils with your thumb and first finger.Place your mouth over the person's mouth, making a tight seal.Breathe into the person's mouth with a firm but a steady breath to make the chest rise. Avoid blowing too hard as the air can bypass the trachea and enter the stomach through the esophagus (feeding tube). Doing so may cause vomiting even if the person is unconscious.If the chest does not rise with the initial breath, re-tilt the head and try again. If the chest still doesn't rise, the person may be choking. In such a case, you would need to check the airway again and clear whatever debris is in the way.If you can clear the obstruction, restart rescue breathing efforts. If you are unable to clear the obstruction and rescue breathing fails to lift the chest, you will need to start "hands-only" modified CPR. Are Online CPR Certifications Valid? 3 If the Heart Has Stopped Chaay_Tee / Getty Images If the heart has stopped beating, rescue breathing can only do so much if the heart is unable to pump oxygenated blood to the brain and rest of the body. In such a case, you would need to either perform modified CPR (also known as "bystander CPR") or professional CPR if you have the competency to deliver chest compressions with rescue breathing. The two procedure can be broadly described as follows: With modified CPR, you would compress the chest twice per second, roughly in tandem to the beat of the Bee Gees' "Staying Alive."With professional CPR, you would compress the chest 30 times at two compressions per second, followed by two rescue breaths. Never attempt professional CPR if you have not been recently trained and certified in the technique. Doing go may harm more than it helps. According to research published in the Lancet, modified CPR was more effective than professional CPR in bystander situations, increasing the rate of survival in people with out-of-hospital cardiac arrest. Does CPR Certification Shield Me From Liability? Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Email Address Sign Up There was an error. Please try again. Thank you, , for signing up. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Panchal AR, Berg KM, Kudenchuk PJ, et al. 2018 American Heart Association Focused Update on Advanced Cardiovascular Life Support Use of Antiarrhythmic Drugs During and Immediately After Cardiac Arrest: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2018;138:e740-e749. doi:10.1161/CIR.0000000000000613. Additional Reading Aufderheide TP, Frascone RP, Wayne MA, et al. Comparative Effectiveness of Standard CPR versus Active Compression Decompression CPR with Augmentation of Negative Intrathoracic Pressure for Treatment of Out-of-Hospital Cardiac Arrest: Results from a Randomized Prospective Study. Lancet. 2011 Jan;377(9762):301-11. doi:10.1016/S0140-6736(10)62103-4. Panchal AR, Berg KM, Kudenchuk PJ, et al. 2018 American Heart Association Focused Update on Advanced Cardiovascular Life Support Use of Antiarrhythmic Drugs During and Immediately After Cardiac Arrest: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2018;138:e740-e749. doi:10.1161/CIR.0000000000000613.