Custodial: Myocardial Protection

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“Every practice regarding cardioplegia that works in neonates- works on adults as well- however it is NOT applicable vice-versa”

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Editor’s Note:

Clearly we as perfusionists are all about patient protection at every tissue level:  The brain, the kidneys, the central nervous system, and obviously the heart (myocardium).

My observation is the following on a routine case involving CPB…

  • On CPB- establish Q- cool or drift-…
  • XC On
  • High dose K+ cardioplegia delivered at usually a concentration of 64 MEQ KCL/L @ 5-7 degrees C x 1,000 cc’s)
  • Intermittent doses as each distal is done (less than 20 minutes seems the standard accepted ischemic time) Low dose K @ 500 or so cc’s
  • Maybe a “hot shot of low dose “K” or pure blood to rewarm the heart and flush out residual pools of K+ after the last distal.
  • Dump in 100 mg of lidocaine- as the XC comes off and it’s a done deal.

It may sound simplistic- but having done hearts at 34+ institutions- it is what it is- and it hasn’t varied much.  You can make it sound more complicated, but the bottom line-that formula is pretty universal.

We are not mechanics, perfusion is definitely an art in regards to managing a pump-run, but in the realest sense- we go with the flow regarding accepted practice and that is something hard to change.

Will the pulse that drives this universal regimen change?  I doubt it.

So here is a pretty interesting discussion regarding what a a lot of us aren’t thinking about once we get happy and see a flat line :)

Follow THIS LINK for a pretty enlightening Myocardial Protection Video:

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Custodial Cardioplegia & Myocardial Preservation

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Click image to view presentation

As the Editor of CircuitSurfers.com, I suppose the expectation is that I am at least up to date and fully informed when it comes to most perfusion techniques.

Custodial Cardioplegia is an unknown and unfamiliar concept to me- so follow along as we learn this together.

The following post will discuss how Custodial Cardioplegia enhances myocardial preservation, and the optimal circumstances on how to employ this technique

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A Refresher Course on Organic Chemistry 101

 

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Heart Protection 101

 

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Basic O Chem

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3 reduction of ATP to 2 after X Clamp

Reduction of ATP to 2 after X Clamp

 

4 Reduction of ATP increse of Lactic Acid

Reduction of ATP & increase of Lactic Acid

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5 Lactate prododuction

Lactate production

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6 Stone Heart

Stone Heart

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Figure 1

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Figure 2

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10 Decrease in ATP

Decease in ATP

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12 Recovery of atp lasts for days not minutes

Recovery of ATP lasts for days not minutes

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13 Decrease in pH in myocardium

Critical pH for patient is 7.0

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14 Critical pH is 7.0

Critical  pH for myocardium is 6.0

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