Capnography made me say, hmmmm! Traumatic Cardiac Arrest Patient

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Specializes in Adult and Pediatric Vascular Access, Paramedic.

Hi all,

I am a paramedic and yesterday we had a young man who crashed his motorcylce into a pickup truck and he presented in traumatic arrest on our arrival, but we worked him per protocol. I intubated him, saw the tube pass through the cords, bilaterally equal breathsounds, although full of crackles; However on capnography he was basically flat with no reading most of the time even with CPR. The highest reading I got was 3 for his endtidal co2 and that was with some fluids and continued CPR. I also saw some smaller waves during CPR, but I think that may have just been the compressions forcing some air up, for lack of better wording. I had the other medic also verify tube placement just to be sure, and she also said it was in. No sounds over the epigastrum, lung sounds bilaterally.

Was this low reading do to his lack of prefusion secondary to massive blood loss (he clearly internally esanquinated as he had no head trauma and had the coloring that you normally see with that, my guess is he tore his aorta on impact).

Just wondering if this is a normal finding in someone with poor perfusion, ie in this case someone who probably has little to no blood in his heart or vasculature.

Thanks

HappyParamedicRN

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Specializes in Cardiac, Pulmonary, Anesthesia.

With decrease perfusion there is a decrease in ETCO2. I can always tell when the blood pressure has dropped before cycling the cuff based on a very slight, slight sudden drop in ETCO2, so your thoughts could very well be the case. I'm skeptical of a absolute zero reading though, and feel like a leak or disconnect was happening somewhere.

There is no one way of being sure you haven't goosed the tube, but remember ETCO2 is the best metric (not saying you goosed it, just saying).

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Sure, if you aren't perfusing your lungs, then you are ventilating pure dead space with no gas exchange and your end tidal gases will be the same as your inspired gas. Atmospheric CO2 is just a fraction of a percent and won't register

Just because someone is doing compressions, doesn't mean they are being effective, I'm sure you know. Hence the emphasis on good compressions in CPR class. Of course, it would be hard to be effective with a ruptured aorta.

Tough case, thanks for sharing

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Specializes in Adult and Pediatric Vascular Access, Paramedic.
With decrease perfusion there is a decrease in ETCO2. I can always tell when the blood pressure has dropped before cycling the cuff based on a very slight, slight sudden drop in ETCO2, so your thoughts could very well be the case. I'm skeptical of a absolute zero reading though, and feel like a leak or disconnect was happening somewhere.

There is no one way of being sure you haven't goosed the tube, but remember ETCO2 is the best metric (not saying you goosed it, just saying).

I am 100% positive the tube was in as myself and another paramedic reasessed it more than once. I did get some endtidal, but that was only after some fluid ran in but it didn't last long.

Happy

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Specializes in Critical Care, Emergency.

ETCO2 is directly proportional to cardiac output. no pressure = no CO2. period. if you saw tube pass cords, and are also sure tube didn't dislodge from time you removed laryngoscope and secured tube, there's really no other cause.

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Specializes in Cardiac, Pulmonary, Anesthesia.

I believe the tube was in. By disconnect I mean a loose connection or contamination of the gas analyzer. I've seen it before and you can loose the wave all together or becomes much smaller. If you had said there was no disconnect, then I'm sure the cause is because the absent CO. No blood to lungs means no blood to exchange gas.

As for the ETCO2, I really wasn't suggesting that it was goosed, but it is noted in several anesthesia texts that while no one method is 100% accurate, ETCO2 is the best indicator. That was just for your information.

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Specializes in Anesthesia.

It sounds like your patient had bilateral pneumothorax and needed a couple chest tubes.

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Specializes in Adult and Pediatric Vascular Access, Paramedic.
It sounds like your patient had bilateral pneumothorax and needed a couple chest tubes.

I was thinking that as well, but his lung sounds were equal, but full of crackles, but I hear air movemnt bilaterally...

Happy

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Happy,

About a year ago I had a women go into flash pulmonary edema secondary to CHF which led to asystole by the time we arrived on scene. We use a LUCAS automated CPR machine that we hooked up and started CPR, I intubated the patient with a large amount of that frothy blood tinged sputum in her airway and ET tube, end tidal co2 turned yellow, good breath sounds, and we placed our capnography device on the ET tube with a reading of 5, good waveform. The reading all of a sudden started to increase rapidly and went from 5 to the 60's and 70's. The reason for this huge jump was we got her pulse back and now her heart was pumping again and perfusing and expelling all of that built up CO2. I would have to believe that she was just not perfusing that well, CPR, let alone CPR by individuals and/or a machine is not that adequate to perfuse the body sometimes. Just look at how much the atrial kick contributes to cardiac output, and the fact that it was a traumatic arrest, I think you did the best you could do. But I would have to say that it was probably due to lack of perfusion like some of the other posters have said.

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