Is There Hope If, After Four Minutes of Rescue Breathing, No Pulse Can Be Found?

How Long Can CPR Take to Work?: Is There Hope If After Four Minutes of Rescue Breathing No Pulse Can Be Found?

Minutes can feel like hours when you are administering CPR in a real-life situation. Because of this, it’s helpful to know how long CPR takes to work. For example, if after 4 minutes of rescue breathing no pulse can be found, what do you do? 

The short answer is that the length of CPR that needs to be given varies from case to case. Sometimes CPR has been successful after a few short minutes; sometimes it takes much longer. Often, it’s not successful at all.

Here we look at examples of how long CPR has taken to work in real-life cases, and what you should do when CPR doesn’t appear to be working and after four minutes of rescue breathing, no pulse can be found. 

What Happens to the Vital Organs During Cardiac Arrest 

All organs need oxygen to function. The body starts to die when the heart, lungs, or brain stop functioning. Failure to resuscitate these organs leads to the failure of other organs around the body.

This process can be reversed with CPR, giving artificial restoration of the vital organs. Without CPR, a person in cardiac arrest will quickly lose organ function because there is nothing to give oxygen to these organs.

CPR can take time to work which is why it is so important to begin CPR as soon as possible.

What Happens During the Initial Stages of CPR

The point of CPR is to return oxygen to the vital organs in the body. Prolonged oxygen deprivation impacts the brain. This begins to happen within three minutes of the heart stopping. The longer the brain is deprived of oxygen, the worse the damage to the organs will be. 

CPR is a manual way of getting blood flowing around the body. This means blood cells carrying oxygen will still reach the organs. It is a temporary fix, however, and the goal of CPR is to restart the heart to a return of spontaneous circulation (ROSC).

However, this does not mean that all is lost if after four minutes of rescue breathing no pulse can be found. If there is no pulse after 4 minutes of rescue breathing or CPR, there is a much-reduced chance of recovery, but recovery is still not impossible.

Examples of Successful CPR: Is There Hope If After 4 Minutes of Rescue Breathing, No Pulse Can Be Found? 

There are times where CPR has successfully returned a heart rhythm to a patient after extended periods of time. Sometimes this leads to a full recovery. Read on to learn about a few different examples of this.

When CPR has Worked After Five Minutes

Vital organs will start to be affected after just minutes of being deprived of oxygen. If there is still no pulse after four minutes of rescue breaths, the advice is to keep going.

While chances of survival decrease with every minute that passes, there have been many success stories in which giving CPR for much longer than five minutes has saved a life.

When CPR has Worked After 20 Minutes

Some medical bodies, such as the National Association of Emergency Medical Services Physicians, suggest at least 20 minutes of CPR should be given to people experiencing an out-of-hospital cardiac arrest. 

While the survival rate in out-of-hospital cardiac arrests where CPR was given for 20 minutes or more is still only 5%, one study showed “multiple cases of survival” after 20 minutes or more of resuscitation.

When CPR has Worked After 90 Minutes

One study showed a 48-year-old man survived an in-hospital cardiac arrest that lasted around one and a half hours. Many would consider this to be impossible, but he is proof otherwise.

The man received CPR for 90 minutes, and seven days later had full neurological recovery.

When CPR has Worked After Much Longer Periods

Of course, in exceptional cases, survival seems almost miraculous.

In 2019 a study presented a 52-year-old Italian mountaineer who had survived cardiac arrest with complete organ recovery after receiving CPR for 5 hours and 44 minutes. This is relatively unheard of, but shows that CPR truly matters.

When to Stop Giving CPR

There is no prescribed “stopping” time when giving CPR. Success rates are on a case-by-case basis. We go into more depth on this in our article, “How Long Should You Continue CPR?”.

It is generally recommended to perform CPR continuously for at least two minutes before assessing a patient’s response. Even if you do not observe a response, continue CPR until help arrives.

What to Do When CPR Does Not Work

Sadly, CPR does not always work. CPR isn’t keeping someone alive, it is buying time until other help arrives.

There is no medically-defined time to stop CPR. If after four minutes of rescue breathing there is still no pulse, continue giving CPR until help arrives. Our minute by minute guide to what happens during CPR explains this further.

It is true that chances diminish with each minute that passes. If after 4 minutes of rescue breathing no pulse is detectable, the chances of recovery without a brain injury are low. Still, it is worth trying in the hope that the victim may survive. As a giver of CPR, you will not always be able to save a life, but by continuing to administer CPR until emergency aid arrives, you can know that you did everything you could.

Performing CPR consistently until a medical team can take over may give enough oxygen to the brain, heart and lungs to mean full recovery for the patient. It is those initial few minutes of CPR that are vital for a chance of recovery.
We can coach your staff in the basics of CPR so they can administer effective and safe aid when needed. Contact us today to learn more.