# Pleth waveform examples



## VFlutter (Feb 25, 2012)

I am trying to put together a poster of pleth waves to go along with our EKG Rhythm examples. Does anyone have some good examples of correct and incorrect pleth waves? I have been searching google and can't seem to find anything good. Thanks


----------



## palmer1121 (Feb 25, 2012)

I have a powerpoint that goes over ETCO2 monitoring that has really good examples.  PM me and I will email you the whole thing


----------



## socalmedic (Feb 25, 2012)

what are you measuring? spo2, etco2, pulmonary venous pressure, Intra atrial pressure? all have different waveforms.


----------



## BorderDog (Feb 25, 2012)

http://www.capnography.com/ 

This site has some info.


----------



## VFlutter (Feb 25, 2012)

socalmedic said:


> what are you measuring? spo2, etco2, pulmonary venous pressure, Intra atrial pressure? all have different waveforms.



Spo2


----------



## Aidey (Feb 25, 2012)

In the EMS setting pleth waveform always refers to SpO2. It is short for the fancy term for the type of instrument the SpO2 probe is. Its something I can't spell (or say) and I'm feeling too lazy to look it up right now.


----------



## NomadicMedic (Feb 25, 2012)

Plethysmograph. 

Really, in EMS it's only useful for detecting an irregular heart beat. 





http://www.amperordirect.com/pc/help-pulse-oximeter/z-what-is-oximeter-plethysmograph.html


----------



## usalsfyre (Feb 25, 2012)

n7lxi said:


> Plethysmograph.
> Really, in EMS it's only useful for detecting an irregular heart beat.


It can be a useful indicator of distal perfusion and acuracy of the SpO2 as well (clinically corelated of course).


----------



## NYMedic828 (Feb 25, 2012)

usalsfyre said:


> It can be a useful indicator of distal perfusion and acuracy of the SpO2 as well (clinically corelated of course).



The SPo2 sensor on our new Phillips MRX monitors doesn't even work half the time. Its such a piece of garbage.


----------



## Handsome Robb (Feb 25, 2012)

NYMedic828 said:


> The SPo2 sensor on our new Phillips MRX monitors doesn't even work half the time. Its such a piece of garbage.



Really? I've never had a problem with ours. If the regular finger piece doesn't work we have the stickies too and that always seems to fix the problem whether it's on a finger or an earlobe or whatever you decide should work.


----------



## NomadicMedic (Feb 26, 2012)

usalsfyre said:


> It can be a useful indicator of distal perfusion and acuracy of the SpO2 as well (clinically corelated of course).



Sure, but how many medics do you know that have any idea what the pleth waveform does? Never mind any idea about assessing distal perfusion. I think if medics are going to learn to look at ANY diagnostic waveform, it should be capnography.


----------



## Aidey (Feb 26, 2012)

Capnography is extremely useful, but all EMTs and paramedics should be able to look at a pleth waveform and determine if they are actually getting a reading or not. Saves a lot of trouble when someone tries to put a NRB on your pt with an SpO2 of 72% who is pink, warm, dry and speaking full sentences.


----------



## NomadicMedic (Feb 26, 2012)

Does your monitor normally display a pleth waveform? Do EMTs regularly use any device that displays a pleth waveform?


----------



## Aidey (Feb 26, 2012)

All of our Lifepaks are programed to show it, you just have to change one of the channels so it is set to SpO2, which is the exact same thing you have to do if you want to see the capnography waveform. Since all of our EMTs are trained in how to set up the monitor for capnography, I don't think it would be that hard for them to check a pleth waveform. 

A quick google search shows that there are both fullsize SpO2 and finger-tip SpO2 monitors that will display a pleth waveform. So any agency could have the ability to evaluate a pleth waveform.


----------



## NomadicMedic (Feb 26, 2012)

To each his own... Seems useless to me. One more "gizmo" for EMTs to play with, I guess.

And our LPs are set to show caponography on channel 3, as we use a filterline on almost every patient. I've never had any reason to monitor the pleth waveform. But, hey... That's just me.


----------



## Aidey (Feb 26, 2012)

It's not really a gizmo in its own right, it is a feature of an existing gizmo that is standard in most EMS agencies. 

A good pleth waveform lets you know if the SpO2 is getting an solid reading or not. If you're going to be treating a low SpO2 it comes in handy if you confirm that it is actually low before hand and not just a poor reading.


----------



## NomadicMedic (Feb 26, 2012)

True, but if you look at a pt who's mentating normally, is pink and dry with no obvious work of breathing, and the SpO2 is 64, you don't need a pleth waveform to tell you that the reading is poor. 

Conversely, a pt with air hunger, obvious WOB and cyanosis needs oxygen, not an EMT fiddling around with changing channels on the lifepak. 

You see? It's not something that is necessary in an EMTs daily practice. Just because the box can do it, doesn't mean you NEED to do it. 

But again, it's your deal... So have at it.


----------



## Aidey (Feb 26, 2012)

I'm not talking about the obvious cases. With the increasing evidence that hyperoxygenation is bad for patients isn't it a good idea to see if the 70yo with chest pain and an SpO2 of 90% actually has an SpO2 of 90% before you put him on oxygen?


----------



## NomadicMedic (Feb 27, 2012)

I still think its a waste of time. You should use your powers of observation to determine if a patient needs oxygen. 

But again, this is my opinion.


----------



## Aidey (Feb 27, 2012)

For something that is a huge waste of time the EDs spend an awful lot of time on it. Every single monitor in all of the EDs here automatically displays the pleth waveform.


----------



## NomadicMedic (Feb 27, 2012)

Let me clarify... I believe it to be a total waste of time for EMTs to use a pleth waveform. If they have a monitor, and you're all fired up to each them waveform analysis, teach them ETCO2 and basic ECG recognition.


----------

