In cardio pulmonary resuscitation, ventilation ratio is used to denote the amount of air that reaches the alveoli in the lungs. A ventilation-perfusion ratio often denotes the amount of air reaching the lungs and the amount of blood reaching the alveoli. These two factors help us assess the concentration of oxygen in the blood.
When performing a rescue on a victim, the victim must be supplied with both compression and ventilation especially in the case of drowning victims. In short, both ventilation and perfusion help the victim recover. The ventilation ratio however, varies from child to infant to adult.
Ventilation – Perfusion Ratio:
- If we decrease the rate of ventilation while keeping the perfusion rate the same, the body does not receive as much oxygen as it needs to meet the required rate for a normal metabolism, and to expel carbon dioxide that is produced.
- If we increase the rate of perfusion while unchanging the rate of ventilation, there is more blood available to produce the carbon dioxide to be expelled. As a result, more carbon dioxide is created than can be exhaled.
Ventilation- Compression Ratio :
The ventilation-compression ratio is the number of compression per rescue breath and vice versa. It is generally two rescue breaths for every thirty compressions in adults and two for every fifteen in children.
For infants in case of choking or drowning, the rescue breaths can be more frequent.
What is the Correct Ventilation/Compression Ratio ?
The correct ventilation/compression ratio for adults is 30:2
It simply means to provide two rescue breaths for every thirty compression, and maintain a steady rhythm. The same is to be followed for both single and double rescuer methods. If there is an additional rescuer, the same method is to be followed, except that each person can take turns with performing the rescue breaths and the compressions without pausing either.
This also enables them to rest from the physically laborious job of giving compression.
Is the Compression Ratio the Same for Children and Infants as well?
No, the compression ratio for children is 15:2.
Most child and infant victims require emergency medical care due to choking or drowning. Because of this, giving more frequent rescue breaths is imperative.
In case of a single rescuer, for a drowning or choking case a rescue breath for every five to ten breaths since the victim needs oxygen to be provided.
What if there are any External Devices Involved?
If an AED or Automated external defibrillator is available alternate 3-4 shocks with a minute of CPR.
AEDs are designed to help untrained rescuers perform near-successful CPR.
CPR should be continued till you see the patient breathing on their own (chest rise and fall) or if the victim regains consciousness. Immediate care to discover the cause of the attack however, should be offered to the victim, to understand the root of the problem.
While practicing successful rescues on victims may not promise a hundred per cent survival, it does give them another chance at life, and that chance no matter how small is deserved by everyone.