I have been an avid reader of the hyponatremia literature for my entire medical career and last week I contributed to a significant new manuscript to the dysnatremia canon.
This link is supposed to work to give people access to the full text of the manuscript.
This feels like a major career achievement. For once I’m not just talking and teaching about other people’s work but sharing my own work, and in a topic I care a lot about. I am so grateful to Michael Fralick who approached me about helping out on the study way back in 2019.
ADH stood for Association with Demyelination in Hyponatremia
Amazing to see it mature from idea to data to manuscript.
The article looks at the rate of osmotic demyelination syndrome in hyponatremia and it is the largest examination of this question that I am aware of. I posted a Tweetorial on the topic here:
And what follows is the draft of the tweetorial (minus the gifs)
Never in the history of medicine has so much been done, by so many, so incompetently, with so little consequence as in the treatment of severe hyponatremia. #Tweetorial 1/10
We all know that we cannot correct hyponatremia too fast and that the speed limit is 8 mmol/L per day. We know this. We still do a terrible job at it. In the landmark George study, 41% of 1,490 patients had their sodium corrected faster than 8 mEq/L. Look at the poor slobs at the left of the graph whose Na actually went down in the first 24 hours 🤪 2/10
Thankfully this incompetence is rarely punished. Of the 611 (41% of 1490) patients who over-corrected in the George trial, only 7 developed osmotic demyelination syndrome (ODS). Screw the sodium correction and you can get away with it 99% of the time. 3/10
I had the good fortune to be invited to help with a research study looking at the incidence of ODS in hyponatremia using the GEMINI database which tracks internal medicine admissions in Toronto. It is amazing that someone you look up to and respect from the medical literature DMs you to join them on an important study. Thanks @FralickMike 4/10
So the gemini database was used to look up every case of hyponatremia (Na < 130) admitted to one of 5 academic hospitals in Toronto from 2010 through 2020.
22,858 cases of hyponatremia. This is a massive study. By far the biggest ever. If you restrict the cohort to just people with a sodium < 120, it is nearly twice the size of George. 5/10
And the Canadians did a better job of correcting the sodium, but still went too fast in 18% of cases, 3632 patients. But hold on, a lot of these people had relatively mild hyponatremia (relative to George). When you break it down by starting Na, Canadians look just as bad the US at fixing the sodium slowly. 6/10
And what was the consequence of all that hyponatremia? And all that rapid correction? Twelve cases of osmotic demyelinating syndrome.
12 out of 22,858 cases of hyponatremia. 0.05%If you divide by starting Na they found an incidence of:
0.3% with a Na < 120
0.015% with a Na > 120
2.5% with a Na < 110 7/10
The part of the manuscript you are looking for that is not there is rates of ODS by rapid versus slow correction. We could not publish this because of the ethical guardrails on this trial. And the statisticians wouldn’t even whisper it in my ear because they know me. Kind of a bummer. 8/10
So what can we take from this paper? ODS is rare, Canadians are just at bad correcting the sodium slowly as the guys in Pittsburgh and the rate of ODS errally goes up as the initial sodium level goes does down, from a trial 0.015% at levels > 120 to 2.5% with sodiums < 110. 9/10
Take a look at the paper and at the George paper.
https://evidence.nejm.org/doi/10.1056/EVIDoa2200215
https://pubmed.ncbi.nlm.nih.gov/29871886/
10/10
Addendum:
Brian Locke asked how I made the gifs in the tweetorial
Did you make the animations? If so, they are awesome and I’d be interested to know how. #MedEd
Also, great study 👏
Originally tweeted by Brian Locke (@doc_BLocke) on March 30, 2023.
They are simple animations in Keynote. Here is the file so you can see how they work.
If this is interesting to you, don’t miss the editorial by Ayus. He’s ready to burn everything to the ground and he called his own number a few times in the refs.
