Mouth-to-mouth resuscitation is a form of artificial ventilation where a rescuer blows air directly into a person’s lungs. This technique is a component of cardiopulmonary resuscitation (CPR), aiming to provide oxygen to someone who is not breathing or is not making sufficient respiratory effort. Its primary goal is to deliver life-sustaining oxygen, essential for maintaining bodily functions when normal respiration ceases.
The Role of Rescue Breaths in CPR
When a person’s heart and breathing cease, the body’s oxygen supply rapidly diminishes. Rescue breaths restore ventilation and deliver oxygen to the lungs. This process facilitates gas exchange, where oxygen diffuses into the bloodstream and carbon dioxide is removed. The rescuer’s exhaled air contains approximately 17% oxygen, sufficient to support life.
Once oxygenated, this blood is circulated by chest compressions, reaching organs like the brain. The brain is highly sensitive to oxygen deprivation and can sustain damage within minutes. Rescue breathing helps ensure a continuous supply of oxygen to the brain, reducing the risk of permanent damage and buying precious time until professional medical assistance arrives.
Administering Mouth-to-Mouth Resuscitation
To administer mouth-to-mouth resuscitation, first ensure the scene is safe. Position the person on their back on a firm, flat surface after determining they are unresponsive and not breathing normally. Kneel beside their head.
Open the person’s airway using the head-tilt, chin-lift maneuver. Place one palm on their forehead and gently tilt their head back, while lifting their chin forward with the fingers of your other hand. This action moves the tongue away from the back of the throat, clearing the airway. Pinch the person’s nostrils closed with the thumb and forefinger of the hand on their forehead to prevent air leakage.
Take a normal breath and create a tight seal by placing your mouth completely over the person’s mouth. Blow steadily for about one second, observing for a visible rise of their chest. This chest rise confirms that air is entering the lungs. If the chest does not rise, reposition the head and try again, ensuring a proper seal.
Deliver a second breath in the same manner, watching for chest rise. Avoid giving breaths too rapidly or forcefully, as this can force air into the stomach, potentially causing vomiting or reducing lung expansion. After delivering two effective breaths, resume chest compressions, maintaining a ratio of 30 compressions to two breaths.
Deciding When to Use Mouth-to-Mouth CPR
The decision to incorporate mouth-to-mouth resuscitation into CPR depends on the underlying cause of the emergency. For adults who experience a sudden cardiac arrest, especially witnessed collapses, hands-only CPR (chest compressions only) is often recommended for untrained bystanders. In the initial minutes, there may still be sufficient oxygen in the bloodstream and lungs, making continuous chest compressions the immediate priority to circulate this oxygen.
Mouth-to-mouth resuscitation is important in scenarios where the cause of cardiac arrest is primarily respiratory. This includes cases such as drowning, drug overdose, or collapse due to breathing problems. In these situations, the person’s oxygen levels are likely already depleted, making the delivery of oxygen through rescue breaths essential for survival.
For all pediatric emergencies, CPR guidelines consistently recommend combining chest compressions with rescue breaths. Children and infants often experience cardiac arrest due to respiratory issues, meaning their oxygen levels are typically low before the heart stops. Providing rescue breaths is particularly important to replenish their oxygen supply and improve outcomes.
For drowning incidents, CPR must include rescue breaths. Drowning is a hypoxic event where the body is deprived of oxygen. Prioritizing rescue breaths alongside chest compressions helps address this lack of oxygen and increases survival.