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CPR Quality - avoid leaning between compressions ?

  1. Sep 9, 2013 #1


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    CPR Quality -- avoid leaning between compressions ?

    This is the first I've heard of "avoiding leaning between compressions". Does anybody know what that means? All I can find so far is the statement itself, not an expansion/explanation on what leaning means. Maybe they just are trying to say to keep your shoulders over the midline of the Pt?

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  3. Sep 9, 2013 #2
    Another example of not so great instructions. They might as well say avoid bad technique. All I can think of is avoid getting into a posture where you're at risk of your contact point slipping forward (from your reference) of your ideal position on the sternum. It's important that the direction of the force is perpendicular to the sternal surface. I'm interpreting "leaning" as something other than perpendicular.
    Last edited: Sep 9, 2013
  4. Sep 9, 2013 #3


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    Did you read the full article? See the heading "Full chest recoil: no residual leaning".

    My interpretation: don't support your own weight on the patient in between compressions, by leaning over the patient and using your hands to stop yourself overbalancing.
  5. Sep 9, 2013 #4


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    Oh! That finally makes sense. I did try to find more info, but missed that I could have clicked into the article, thanks.

    So better words would be "avoid leaning on the patient between compressions". Makes much more sense now :smile:
  6. Sep 9, 2013 #5
    I agree, that makes sense. It didn't occur to me that trained responders might not allow for full recoil. To me, "lean" means off perpendicular like a certain tower in Italy.
    Last edited: Sep 9, 2013
  7. Sep 25, 2013 #6
    AlephZero certainly has the main point.
    It is also important that you raise your arms and hands with your full upper body so that you will be in position to apply force with your full upper body. AHA CPR instruction states that you should be depressing the chest a full 2 inches at a rate of 100 per minute. Most people will find this seriously exhausting. If you're a 150 pound person trying to keep CPR going on a 200 friend, you need the best possible technique to keep the compressions going for as long as possible.
    With that in mind, you can see that it's all about leaning and nothing about arm strength.

    Of course, you're told to recruit someone to call 911. That's most important. Then the next person (or the same person) gets the AED, if there is one. What they don't tell you is that if there is a third person there, reserve the biggest of them to assist with the compressions. If CPR needs to be continued beyond your endurance, and the AED is unavailable or ineffective, your next best choice is to give instruction and coaching to that big guy.
  8. Sep 27, 2013 #7


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    In this video (But this is NOT an AHA video) they give the more easily understood "allow the chest to recoil completely" (around 4:13).

    Here is an AHA video and they have reversed the order from ABC to ACB.

    I don't understand why they recommend chest compressions to start if there is no breathing. Couldn't the airway be blocked and the heart still beating, in which case maybe attempt to remove the obstruction? Or does CPR also clear airway obstructions?

    I also wonder: what is the guideline for performing hands only CPR versus traditional CPR with artificial respirations and chest compressions?
    Last edited by a moderator: Sep 25, 2014
  9. Sep 27, 2013 #8
    One recent change (ECC2005) that is very significant is that checking for a pulse has been dropped. The problem was that pulse check had to be completed within 10 seconds and in that amount of time, the success rate was atrocious - even among seasoned paramedics. So now, the presumption is that if the victim is unconscious and there is no breathing, then the victim is either already dead or will very soon loose his heart beat.
    Chest compressions can dislodge a breathing obstruction - but not as reliably as the back blow/abdominal thrust combination.

    Here's the important point. When you heart stops, there is still oxygen in your blood. Probably not enough to revive you, but enough to make a big difference in you resuscitation and recovery. So step one is to make sure that good blood circulates. After thirty chest compressions, you should then do two good breaths - at which time you may clear the throat. But even is you can't do the breaths, resume the chest compressions.

    Whether you do hands only or full CPR, you need to notify get help at the start of the process. You're only buying time for the victim until help arrives in the form of an AED or paramedics. As I described above, the most important procedure is the chest compressions.
    The purpose for hands only CPR is three-fold: 1) Some people are put off by the "yuck" factor. They don't want to touch a sick mouth with their own mouth. 2) They want to make things simple for people who might not be inclined to remember anything more complex than call 911 and do 2-inch compressions to the song "Stayin' Alive". 3) They have found that even when there is a person qualified to do CPR when someone falls unconscious, in a large portion of the time, that person does not come forward. So, by providing a simple option you may have more qualified people around and less reason for them to hesitate.
  10. Sep 28, 2013 #9


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    It looks like they've found that chest compressions are statistically quite important - even the number has changed from 15 to 30?

    Is mouth-to-mouth possibly dangerous for the rescuer - ie. can the rescuer get a disease, or is it only a "yuck" factor?

    I've never heard an official guideline for this. A number of doctors have told me that it's a personal decision, and they would most likely provide mouth-to-mouth even without a mask (this was 20 years ago, way before hands only CPR). I suppose the hands only CPR is, as you say, meant to address this.
    Last edited: Sep 28, 2013
  11. Sep 28, 2013 #10

    Table V in the above link is a short list of infections that have been transmitted by mouth to mouth resuscitation. The author cites one documented case of tuberculosis being transmitted this way. The theoretic risk of hepatitis C is also discussed. Transmission can go both ways, from subject to responder or responder to subject. It's advised that those doing direct mouth-to-mouth ventilation follow-up to see if any infection was found so treatment can be instituted.

    The revision of the guidelines by the AHA recognizes these problems and emphasizes that rapid chest compressions (at least 100 per minute) to a depth of 3.5-5 cm is critical and should be be started immediately regardless of whether or not mouth to mouth ventilation is done.
    Last edited: Sep 28, 2013
  12. Oct 10, 2013 #11
    The 30 chest compressions, 100 compressions per minute, and at least 2 inch depth for adults are all based on studies of blood perfusion. After 15 compressions, you are only starting to get the perfusion to the brain that you need for eventual resuscitation.

    There are, of course, mouth pieces - some small enough to keep on a key chain. I have one in my car and in my office. Realistically, they won't be handy enough if I needed them. In a lot of cases, I consult my town paramedics on these matters - but they always have the mouth pieces handy.

    It can be yucky. They may have vomited. There may really be diseases. I wear an under shirt and I'm plenty capable of tearing a piece off and folding it to about four layers. That should be plenty. More than anything else, it depends on how you value the privilege of saving a live - or, in the case of a friend or relative, how much you're willing to do for them.

    BTW: Whether they've vomited or not, if the AED works for them and they begin to revive, you roll them onto their side (the recovery position) where they may vomit again.
  13. Oct 10, 2013 #12
    I agree. The fact is, a lone responder without equipment or advanced training is unlikely to be successful under any but the most fortuitous circumstances. At the very least, a second responder should come in to assist within a minute or two.

    In a witnessed cardiac arrest, 20 to 30 percent of the blood volume will be arterial blood with, ideally, an O2 content of about 17-18 mL/dL. For the remaining venous blood, it's about 12-14mL/dL. Just getting this circulated is of critical importance. With a second responder ventilating the patient, I would expect that the chance of success improves considerably provided advance cardiac life support is instituted by trained equipped personnel before too long.

    Last edited: Oct 10, 2013
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