Basic Rhythm Course

  1. I am getting ready to teach a basic rhythm class for the first time and I am not a cardiac nurse. I have always done med - surg and OR nursing and am now in an educational position. This is a little out of my comfort zone. I have an outline of what I will be teaching, some review of A and P and then I will start with Sinus Rhythms and atrials and move on to blocks. I still have a little trouble with blocks, I know what I want to say but somehow it never comes out quite right. Any suggestions for making this class alittle more interactive and keeping attention would be appeciated
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    About suni

    Joined: Aug '02; Posts: 511; Likes: 205
    surg rn; from US
    Specialty: 15 year(s) of experience in med surg


  3. by   turnforthenurse
    What exactly are you having trouble with regarding blocks? Trying to teach them in an understandable way?

    1st degree blocks are easy. Just remember a prolonged PR interval, >0.20sec. Not really anything to worry about.
    Causes: digoxin, beta blockers, CCBs, increased vagal tone, hyperkalemia, MI, degeneration of conduction pathways associated with aging or idiopathic.

    For the others, I used mnemonics to help me because I had a hard time keeping them straight.

    Long, longer, drop...then you have a Wenckebach (2nd degree type 1). Recall that with this block you have a PR interval that progressively becomes long, then longer and then you have a dropped beat (no QRS). This block isn't very concerning. It can progress to a higher level block, though. Just monitor for symptoms that = compromised hemodynamic status.
    Causes: same as above. Commonly follows an acute inferior wall MI.

    If your P's don't always go through, then you have a Mobitz II (2nd degree type 2). This block is more serious than a Wenckebach. It can quickly progress to a 3rd degree block (the most serious of all!) or progress to ventricular standstill without warning. There is usually more than 1 P wave (sometimes 2 or 3 or more) before a QRS (P's don't always go through to the Q!).
    Causes: acute anterior wall MI, acute myocarditis, age-related conduction pathway degeneration. Usually not drug-related unlike Wenckebach and 1st degree blocks.

    If your P's and Q's don't agree, then you have a 3rd degree.
    With this type of block, you have complete AV-dissociation. The P's are doing their own thing and the QRS' are doing their own thing (they're not "married" to each other) - there is no relationship between them. A majority of the time these rhythms are slow (ventricular rate will vary from 20-60bpm depending if they are paced by the AV junction or ventricles) and these patients look like CRAP, oftentimes hemodynamically-compromised. These patients NEED a pacemaker. Slap on some transcutaneous pacer pads until a more permanent (or permanent) pacemaker can be placed. This rhythm can also lead to ventricular standstill without warning.
    Causes: inferior wall MI, ischemic heart disease, drugs (dig, beta blockers, CCBs, though usually this doesn't occur with drug toxicity), acute anterior MI, hyperkalemia, acute rheumatic fever.

    A Mobitz II vs. a 3rd degree block may look similar. The key is to look at the PR interval. In a Mobitz II (2nd degree type 2) block, you will see a consistent PR interval. It may be WNL or it may be prolonged (>0.20 sec) but it remains consistent.
    In a 3rd degree block, the PR interval is variable. It may be 0.60 sec one moment and then 0.20 sec the next or something.

    Hope this helps! Good luck!