respiratory arrest

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Does anyone know how long it will take for cardiac arrest to occur after respiratory arrest without CPR?

I get that the emphasis is on compressions, but I wonder about the "30 min O2 reserve" part - I can't find this anywhere on the AHA website. Do you have a link? This is new information for me. Thanks

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Specializes in Advanced Practice, surgery.
This is actually why the new guidlines are not suggesting breaths at all anymore,.chest compressions only. Depending on the pt, you may have up to 30 min of reserve O2. Check out the AHA website for new guidlines.

The European Guidelines still have rescue breaths in there, but with emphasis on compressions. (http://www.resus.org.uk/pages/bls.pdf)

Compression-only CPR is another way to increase the number of compressions given and will, by definition, eliminate pauses. It is effective for a limited period only (probably less than 5 min)14 and is not recommended as the

standard management of out-of-hospital cardiac arrest

do the AHA guidelines have a different approach?
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I just recertified my AHA BLS and, although it is all over the news that the new emphasis is on compressions, the guidelines still included 30:2 compression/ventilation ratio for 1 rescuer and 15:2 ratio for 2 rescuers. And I am still curious to see some data on the 30 minute O2 reserve thing. Thanks

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"Assuming I have a healthy patient who is well denitrogenised, I could make them apneic for nearly 10 minutes or so before their saturations even fall below 90%."

Sorry, but I have to challenge this statement - how have you verified this "fact"? I would hate to be the experimental subject!

You can easily find this information with a basic google search. This is also taught around the country at various airway management courses. You can even find cool graphs and so on where you have a healthy, denitrogenised (pre oxygenated), 70kg patient go about 10 minutes before desaturation occurs.

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Specializes in CRNA.
There is no one answer to this.

Just know that it WILL occur, and sooner rather than later.

There is one answer and that answer is FRC. Once the functional residual capacity is depleted the dude meets Jesus unless someone is around that actually knows how to ventilate/oxygenate the gomer. While no individual can be completely denitrogenated (lung physiology, basic organic chemistry and physics prevent this), a properly preoxygenated patient can go approx 6-8 minutes before desaturating (10 minutes is kind of a stretch Gila, maybe an olympic free diver could go this long, but not an average joe).

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A Google search did not yield any information regarding a person's oxygen saturation remaining above 90% after 10 minutes of apnea, Gila. And to RN-Cardiac, nothing that I can find on the AHA website indicates a person may have up to 30 minutes of reserve O2.

I would just like to see some scientific evidence of these "facts," since they seem a bit unbelievable.

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A Google search did not yield any information regarding a person's oxygen saturation remaining above 90% after 10 minutes of apnea, Gila. And to RN-Cardiac, nothing that I can find on the AHA website indicates a person may have up to 30 minutes of reserve O2.

I would just like to see some scientific evidence of these "facts," since they seem a bit unbelievable.

Free divers do it all the time.

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There is one answer and that answer is FRC. Once the functional residual capacity is depleted the dude meets Jesus unless someone is around that actually knows how to ventilate/oxygenate the gomer. While no individual can be completely denitrogenated (lung physiology, basic organic chemistry and physics prevent this), a properly preoxygenated patient can go approx 6-8 minutes before desaturating (10 minutes is kind of a stretch Gila, maybe an olympic free diver could go this long, but not an average joe).

I would agree. I stated earlier that you in fact have a huge range in patients. I can bet that you have probably seen some of the data and charts that compare desaturation time in certain patients. It's amazing that simply making somebody obese or moderately ill can have a major impact on desaturation time.

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I guess that means you couldn"t find any scientific evidence for it either...

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http://journals.lww.com/em-news/_layouts/oaks.journals/ImageView.aspx?k=em-news:2006:08000:00024&i=FFU2

Wolters Kluwer Health

It's clearly possible for normal patients to go up to eight minutes, having somebody with exceptional traits such as a free diver going around 10 minutes is not outside the range of possibility.

Even if you disagree, you have to agree with eight minutes.

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Specializes in Spinal Cord injuries, Emergency+EMS.
"Assuming I have a healthy patient who is well denitrogenised, I could make them apneic for nearly 10 minutes or so before their saturations even fall below 90%."

Sorry, but I have to challenge this statement - how have you verified this "fact"? I would hate to be the experimental subject!

in the anaesthetic room perhaps ? although it would be a brave or stupid practitioner that waited 10 minutes before intervening ...

or as others have said free diving etc ..

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Learned something new today!

However the comment by RN-Cardiac that 30 min reserve was possible was a real exaggeration!

Thanks, Gila!

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