Image from Life in the Fast Lane
Thanks to Dr. Steve Field (Resident at Resurrection EM program) for the idea and card. Also take a look at Life In the Fast Lane's extensive review of ECG abnormalities and their causes.
Feel free to download this card and print on a 4'' x 6'' index card.
See other Paucis Verbis cards.
Reference
Diercks DB, Shumaik GM, Harrigan RA, Brady WJ, Chan TC. Electrocardiographic manifestations: electrolyte abnormalities. J Emerg Med. 2004 Aug;27(2):153-60. Pubmed .
Good reference. FYI the PDF links to the PV card for EMTALA rules.
ReplyDeleteFixed, thanks for your comment and the observation.
DeleteNice PVC, as always! Thank you for the hard work!
ReplyDelete(But...soapbox warning...)
However, I don't agree with the association between slow rate and high potassium. I think in a right-now-baby-cow dx it falls into the category of widespread, dangerous "medical myth." Yes, bradycardia will likely happen at some point if we don't intervene...but so will asystole.
I think the best rate-related statement we can make about hyperkalemia is that it can produce a rate that is slow, normal OR fast; and a rhythm that is regular, irregular, or temporarily absent for long enough periods to cause the clinician to suck up the ambulance bench seat PR (trust me, I did it once).
Amal Mattu speaks frequently about the slow mimics of VTach--beware slow VTach because there is a good chance that it isn't.
http://www.epmonthly.com/clinical-skills/ekg/ecg-pearls-beware-the-slow-mimics-of-ventricular-tachycardia/
ECG # 7 at http://lifeinthefastlane.com/ecg-library/basics/hyperkalaemia/ is one example of severe hyperkalemia at a normal rate.
This video, that I absolutely love, is another at a faster rate: All LA Conference September 6, 2007: A Case of Arrhythmia? - Presentation and Treatment of Hyperkalemia
http://www.alllaconference.com/index.php?option=com_content&view=article&id=2345&catid=41%3Aalllaconference&Itemid=1
I have been to several lectures and seen discussions on the interweb where hyperkalemia is described as bradycardic entity, while at the same time they are showing normal-rate or tachycardic-rate ECG's with severe hyperkalemic features. We need to look for signs of severe hyperkalemia at any rate, especially below 120-140.
The last, semi-related, thing I would like to mention is: be sure to look for sine wave development in all 12-leads. Surprisingly, sometimes one or two leads will start to sine before the others..I would see that as a sign (pun intended) of things to come and it would certainly trigger my threshold for action.
You can see this if you compare leads I and V2 in ECG example #1 at http://lifeinthefastlane.com/ecg-library/basics/hyperkalaemia/ Lead V2 makes you say damn!! Lead I should make you say OMG, Shut The Front Door!!
Thanks again for all your hard work. FOAMed on...
Mike Sherriff
Mike, thank you so much for reading and your comments. This is the beauty of FOAMed, we can put our work out there and have people like you contribute to our discussion and increase our knowledge.
DeleteWow Mike. What a thoughtful explanation. I'll be sure to look through your references. Thanks for the comments!
DeletePlease also recall that the classic progression of findings in hyperkalemia are actually "classic" (translation: uncommon) -- in one study that I can't find right now, half of people had high K without any peaked T waves.
ReplyDeleteThanks Graham, that's very true.
DeleteAgreed Graham. Good point. Most of what we teach are classic cases which are often less common than we'd like!
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