0.9% Saline vs. Ringer's Lactate: Which one causes an increase in potassium?

Effects of Normal Saline vs. Lactated Ringer's during Renal Transplantation

0.9% saline is 154mmol/L of sodium and 154mmol/L of chloride. That's it. There's no potassium, calcium, magnesium, nor buffering agent in there. Ringer's lactate, however, has 130mmol/L of sodium, 109mmol/L of chloride, 4mmol/L of potassium, 28mmol/L of lactate, and 3mmol/L of calcium. One would expect that the solution containing potassium would cause a greater increase in potassium than the one without potassium, right? Well, not so fast. Large volumes of sodium chloride, produce a hyperchloremic metabolic acidosis. What happens during acidosis? Well, there's a shift of potassium from the intracellular space to the extra cellular space. Much of this has to do with the strong ion difference which I will be breaking down in the near future. In this study, 52 patients patients received either LR or NS during their renal transplants.

Here are the findings: This has been copied and pasted from the article. Please download it and read it for yourself.

"Patients in the NS group had a lower mean PH level during the transplantation compared with those who received LR (p < 0. 001).

Mean serum potassium levels in the NS and LR groups were 4.88 ± 0.7 and 4.03 ± 0.8 meq/L, respectively (p < 0.001).

Mean changes of the serum potassium were +0.5 ± 0.6 meq/L in the NS group and –0.5 ± 0.9 meq/L in the LR group (p < 0.001).

Mean changes of PH were −0.06 ± 0.05 in the NS group and –0.005 ± 0.07 in the LR group (p < 0.001)"

If next time someone tells you that LR causes hyperkalemia, you can be armed with data. I have other articles with similar results that I plan on sharing in the upcoming days.

I don't know what to make of that thrombosis phenomenon they found. Must keep an eye out for more data regarding that.





Mohammad Reza Khajavi, Farhad Etezadi, Reza Shariat Moharari, Farsad Imani, Ali Pasha Meysamie, Patricia Khashayar & Atabak Najafi (2008) Effects of Normal Saline vs. Lactated Ringer's during Renal Transplantation, Renal Failure, 30:5, 535-539

Link to Abstract

Link to FREE PDF

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Mechanism of Hypokalemia in Magnesium Deficiency

In the ICU, we are at times obsessed with making our patients “euboxic” or better said, all labs values within normal ranges. That being said, electrolytes are something we replete every day and our nurses often have protocols which instruct them on how to manage and correct these derangement to hopefully optimize the outcomes of our patients. When I was a resident, one of my mentors and a good friend to this day taught me to correct the Magnesium before correcting the potassium. This left me scratching my head. It made no sense. And the he went on to explain the mechanisms listed in this article and my mind was blown. How much other stuff do I not know? How come I wasn’t taught this in med school? Well friends, there A LOT that we weren’t taught in med school or even residency and fellowship training for that matter. That pretty much why I’m on this lifelong learning journey and hopefully bringing you all along for the ride. This article is free and it’s a good review for you all to check out. To the cool nurses on Instagram, mid sharing this with your colleagues? This is also must know medicine for any internal medicine intern and resident working the wards and ICU. Tony Breu totally killed this subject in a much more thorough and intelligent manner than I did several months ago on twitter. Follow him @tony_breu.
-EJ

Link to Abstract

Link to PDF

Huang, C.-L., & Kuo, E. (2007). Mechanism of Hypokalemia in Magnesium Deficiency. Journal of the American Society of Nephrology, 18(10), 2649–2652.

Although great care has been taken to ensure that the information in this post is accurate, eddyjoemd, LLC shall not be held responsible or in any way liable for the continued accuracy of the information, or for any errors, omissions or inaccuracies, or for any consequences arising therefrom.