Cardiac Help Needed.....

Nurses General Nursing

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Hi....:nuke:

I am new to this forum am in my last year of RN school and am really struggling to understand the concepts of afterload and peripheral/vascular resistance. Is anyone out there able to explain it in really basic terms so I can try to 'get' it........

Thanks

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Specializes in Rural Health.

http://www.icufaqs.org/

This website is a lifesaver for all that kind of stuff. They break it down, make it VERY easy to understand, give you examples and help you think the process thru.

This website is what finally helped me pull it all together

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http://www.icufaqs.org/

This website is a lifesaver for all that kind of stuff. They break it down, make it VERY easy to understand, give you examples and help you think the process thru.

This website is what finally helped me pull it all together

What an awesome resource!

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I had a nursing instructor (who was an NP) my last rotation of nursing school who was awesome at giving examples of how to understand things.....don't know if this will help you but she explained to me the preload, & afterload was to think of it as a sling shot......and the force (how far the sling shot has to get pulled back) to get whatever it is as far as possible...hence to amount of pressure/resistance that has to be overcome to get the blood circulating........does this make sense????? It really made me understand the concept ......If I can find my old notes I will post what I have down exactly.....hopefully I didn't shred them already...........

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That ICU site is phenomenal!!! I am saving that to my computer so I can use the info for reference during work..........great great site!!!!!!

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Thank you for the great link....it makes things really easy to understand, I will pass it along to my fellow students!!

As for the afterload, here is my confusion......the book states that an increase in afterload results in a decrease in cardiac output.....but.....if I use the slingshot analogy then I don't understand the decrease in CO....Help!!!!

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Specializes in Telemetry/CCU/Home Health.

I always picture afterload as a hose with a clamp on it, this clamp squeezes the hose and therefore supplies the resistance that must be overcome to get the blood where it needs to go...this image is not my own, it came from a mnemonic book of nursing that really helped with visualizing the concept.

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Specializes in Rural Health.

Afterload is the pressure required for the L ventricle to eject the blood into your system....Your body has a natural resistance that is "normal" which is known as the SVR (systemic vascular resistance) which keeps the blood from flowing backwards.

So now your blood is flowing along all nice and good, SVR is normal, no problems right.....

Now, suddenly your SVR increases so it's harder for that L ventricle to pump and it pumps even harder to get the blood into the body.

Your heart is working so hard now and it's ineffective because SVR is high. Whenever your heart is ineffective (usually regardless of why) CO is decreased.

That's how I've been taught, maybe someone else has a better example????

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Specializes in CT-ICU.

That is an excellent example, Mom2.

My instructor told us to think of the afterload as the resistence you would feel if you were trying to open a car door on a very windy day.

That "pushing against a strong wind" would be the afterload.

I actually like your example better though, it is spot on!

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