WuLabsWuTecH
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also, without getting too far ahead, it is important to understand the hemodynamics of CPR first...
for example, during compressions, not that much blood is pumped out... the hemodynamic principal of negative intrathoracic pressure has been proven to be the most important, and least understood. basically, the upstroke cycle of CPR is what helps perfusion the most, increasing preload and filling chambers...
also, understanding things like why you don't do compressions if an arrest is witnessed, but why you do at least 2 minutes if it isn't... why compressions are more important then ventilations, what happens when you interrupt the compression cycle, etc...
Some EMT's take CPR for granted because the chances for saving someone are slim to begin with... others take it for granted because they don't know any better...
if you really want to know how to do it correctly, have a real working knowledge not of the steps, but "why" the steps.
They why you do 2 minutes of CPR first is to ensure adequate oxegenation. When you defib, you try to get the heart to stop firing randomly, and hope that it resets itself into firing in a synch'd pattern. What happens is that the myocardium is a special muscle that can cause electrical impulses w/o the brain through various uses of nodes. Anyway, it has a better chance of resetting itself when its oxegenated. If you see the guy fall, he was breathing just a second ago so it shuold be oxygenated. If you arrive on scene, he may have gone w/o oxygen for 5 minutes. If old-school (January 2008 style) bystander CPR in progress and you think he is adequately oxygenated, then go ahead and defib. If new-school "compressions only" CPR in progress, Take over and do Real CPR for 2 minutes to oxygenate the myocardium.
Am i correct?