The number of breaths is standardized during cardiopulmonary resuscitation (CPR). The current guidelines and practice is that during CPR, the ratio between chest compressions and breaths are 30 to 2, respectively. The same number of breaths is also equal during 2 person- rescuers under advanced practice by clinical staff members in hospitals, clinics and Emergency Medical Services (EMS). Rescue breaths for a victim who has a pulse but not breathing is 1 breath every 5 seconds.
It has been taught that untrained rescuers can provide compression- only CPR. If this is the case, why need to provide rescue breaths? Furthermore, why does the number changes when a patient’s heart begins to beat? Lastly, how does 2 rescue breaths help the body and why do we need 2?
Part of the reason for the number and the need for rescue breathing, also known as ventilations, is in part anatomic. Just like compressions that mimic normal heart beat, rescue breaths are done to mimic normal breathing for the victim. We want a victim’s body to be able to function especially during this time of crisis.
Breathing has many benefits. The important ones in regard to CPR include below:
- Exchanges oxygen from the environment with harmful carbon dioxide from the body through the lungs.
- High levels of carbon dioxide in the body can increase the body’s temperature, which is further increased by the accumulation of lactic acid from muscles.
- Improves circulation through the pressure changes in the lungs.
Normally, respiratory rates for infants (<1 year old) are 30- 60 breaths a minute. Young children (1- 8 year old) normally breathe at a rate of 24- 30 breaths a minute. All other ages breathe at a rate of 12- 20 a minute. The different rates are due to body size. Smaller sizes have faster circulation rates and so needing faster turnover of carbon dioxide (CO2) and oxygen (O2), which then causes faster breathing. Bigger sizes have a circulatory system that takes longer to travel around the body, therefore slower CO2/ O2 turnover and in turn slower breathing.
Compression- Only CPR
It is important to point out then that between the heart and the lungs, the heart is the primary driver of the cardiopulmonary system. A person can have a respiratory arrest (stop breathing) and the heart could continue functioning. However, it cannot be true the other way around. The lungs cannot continue functioning during a cardiac arrest, which is when the heart has an abnormal rhythm causing decreased or no blood being pumped to the body. This brings us to the reason why untrained rescuers could provide compression- only CPR without the use of rescue breaths. This is also why the big change in 2010 from the Airway- Breathing- Circulation process to Circulation- Airway- Breathing with CPR beginning with chest compressions. On another note, starting with chest compressions provides organs in the body with the nutrients and oxygen that the victim had prior to cardiac arrest that is still in the blood.
Technically, a rescuer could continue providing compression- only CPR until Emergency Services arrives without the need for rescue breaths. The advantage of this is the decrease in interruptions in chest compressions. However, the importance of rescue breaths is the improved chance of survival for victims. As was mentioned earlier, breathing has very important benefits for the body. Without it, we deprive the body of CO2 and O2 exchanges in the lungs, improved circulation of blood and the oxygen requirements for important organs. This is especially true for children and infants when oxygenation is extremely compromised compared to adults.
Breaths in CPR
During instances when the heart is pumping but the lungs are not functioning, rescuers are trained to provide the victim with 1 breath every 5 seconds. It is a fact that without breathing, the heart will eventually stop as well. The reason is the loss of oxygen needed for continued function. The heart, being one of the most active and strongest muscle organ in the body, needs as much oxygen as possible. When no oxygen is present for energy production, the heart will fail and the victim goes into cardiac arrest. The brain is also an organ that requires oxygen. Without it, even if the heart is pumping, the patient may be brain-dead and/or require a ventilator for continued life. With 1 breath every 5 seconds, oxygen is being continuously provided and gas exchange is at its optimal function despite the patient’s current condition. As mentioned earlier, breathing, although manual, can help with heart function by giving the heart some rest while blood is being circulated.
During CPR, the process is 30 chest compressions followed by 2 breaths. It is repeated 5 times or 2 minutes. Two rescuers make the chest compression to breaths ratio changed to 15 to 2, respectively. 2 breaths help with gas exchange in the lungs and also provide adequate lung volume during assisted inspiration and expiration. Again, this is especially helpful for children and infants where oxygenation in the blood prior to the arrest decreases due to the shock, so chest compressions will not be delivering content-rich blood to the rest of the body.
Compression- Only CPR vs Compression with Breaths
It has been established that compression- only CPR is as reliable as conventional CPR because of the content- rich blood that the victim had prior to the arrest and that there’s enough in the blood before the arrival of EMS. What we need to remember is that there is no guarantee how long EMS will take to come to the rescuer’s location. Therefore, it is important to learn not only chest compressions, but rescue breaths and the use of the AED.
Thank you for reading.
Read other topics in our blog. Click here.
To register for an upcoming course with us, please click here.
Need to request a group/ corporate course? Click here.
Check out our featured products at our store.