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Defibrillation and the heart

  1. Jul 9, 2011 #1
    I had this first-aid lecture today, and something I heard got me confused.

    So the lecturer said that the "peeeeeeeep" and no electrical impulses being read by the electrocardiograph and the doctors continuing to defib the patient in the movies is basically wrong. That there ought to be some sort of electric pulses for the defib to work.
    Now I knew that defibs were used to correct the hearts rythm, but what I cant comprehend is why wouldnt in work if the heart had stopped completely? Because I've always thought it would.

    Thanks in advance,
  2. jcsd
  3. Jul 9, 2011 #2
    It's called defibrillation because it can convert ventricular fibrillation to a functional rhythm. Fibrillation is localized disorganized activity of the heart muscle which does not produce effective pumping action.

    The true "flat line" ECG rarely, if ever, responds to external defibrillation. There's nothing there to convert. The most effective treatment, when possible, may be to install an internal (transvenous) ventricular pacemaker via a right arm (brachial)vein, right jugular vein or the right femoral vein from the groin area. Of course it doesn't always work since a flat line ECG (asystole) has a very poor prognosis, but it's better than wasting time by repeatedly trying to defibrillate a heart that's not fibrillating. Drugs are administered to optimize the environment for restarting the heart. There are also external (transcutaneous) pacemakers that can be tried.
    Last edited: Jul 10, 2011
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