Thursday, October 16, 2014

Lactated ringers and hyperkalemia: A blog post meriting academic credit

In a recent post, I suggested that physicians should receive academic recognition for certain social media activities. "Myth-busting: Lactated Ringers is safe in hyperkalemia, and is superior to NS," written by Dr. Josh Farkas (@PulmCrit), is a great example of why that is true.

Using only about 1250 words and 6 references, he explains that infusing lactated ringers not only does not cause harm, it is actually superior to normal saline in patients with hyperkalemia, metabolic acidosis, and renal failure.

I highly recommend reading the post which should take you only a few minutes. If you're too lazy to do that, here's a summary.

Dr. Farkas found no evidence that lactated ringers cause or worsens hyperkalemia. In fact, he presents some solid evidence to the contrary.

If the serum potassium is 6 mEq/L, a liter of lactated ringers, which contains 4 mEq/L of potassium, will actually lower the potassium level.

Because almost all potassium (~98%) in the body is intracellular, the infusion of any fluid with a normal potassium content will result in prompt redistribution of potassium into the cells negating any of the almost negligible effect of the potassium infusion.

A normal saline infusion is acidic, resulting in potassium shifting out of cells and increasing the serum potassium level. Lactated ringers, containing the equivalent of 28 mEq/L of bicarbonate, does not cause acidosis.

There's a lot more in the post. Read it.

This issue is arguably the most misunderstood fluid and electrolyte concept in all of medicine.

In my opinion, the post should be displayed on the bulletin boards of intensive care units, emergency departments, and inpatient floors of every hospital in the world and should be read by every resident or attending physician who writes orders for IV fluids.

Disclosure: I've never been a fan of normal saline. Two years ago I wrote a post that discussed two papers showing that because of its negative effects on renal function, normal saline was inferior to lactated ringers in critically ill patients.


frankbill said...

Thanks for this information. As our group talks a lot about K problems this fits right in. I have posted about this link to our group.

Kind of a reverse of this is a problem with doing a blood K draw. If not done right K gets released for blood cells into plasma causing tests results to show false hyperkalemia.

Skeptical Scalpel said...

The lab will usually notice that the specimen was hemolyzed and note it when posting the result.

Unknown said...

Thanks so much for your blog post and encouragement. I've previously read your posts about academic credit for blogging, and certainly agree with you. One reason I started the blog was that I was working very hard on lectures, but a lecture to a small group of people has limited impact. If I put the same amount of effort into a blog, it may be read by thousands of people and is freely available online as a reference.

Over time blogging hopefully will be better recognized as a legitimate academic activity. In the interim, I'm happy to be connecting with clinicians around the world and learning more about medicine. I have found that social media promotes more rigorous thinking by bringing us into contact with people who have different perspectives on medicine.

Best, Josh

Skeptical Scalpel said...

I'm happy to help. I enjoyed the post.

Tell me your chairman's email address and I'll put in a word for you in the next promotion cycle. :-)

frankbill said...

From a patient's point of view it is going take some time before social media is accepted as legitimate academic activity. I have been doing online research for 9 years now. I have what so far is an undiagnosed problem most likely due to an adrenal adenoma.

Some of the testing that is needed to show the adenoma is functioning are affected by meds.

When I try to tell Dr this they ask where I got the information I tell them on the internet. There response is any one can put any thing on the internet. They will not look at the source to see if it might be right.

Of course if Dr were reading the printed journal they should all ready know how to due proper testing. Of if unsure of how to due testing check with the testing lab on how the test should be done. They don't even do this. The VA uses Quest Labs and Quest labs tell how the test should be done.

I do believe that once social media is accepted is being a better way to exchange medical knowledge there is going be much improvement in the way health care is provided.

Anonymous said...


What I do is give them the citation and the link to where it is online. The problem is more that a non medical person gives the link. I don't see why except for personality issues on the part of the doctors. Now that we can see medical information, there is a good amount of it I and others can figure out for ourselves. Doctors don't like the loss of power.

Or the kick in the go. Done that enough.

frankbill said...


Do they then look at the citation and link online? Or do they just keep there head in the sand?

Anonymous said...

They keep the head in the sand. These are only certain ones of them that do this. Those are the ones who don't give me straight answers, etc.

Skeptical Scalpel said...

Some keep their heads in the sand; some don't.

frankbill said...

We have someone with Liddles in our yahoo group. He had recent minor surgery. Seems like things didn't go well for him He thinks it is due to IV solution.

Before the surgery all bloodwork was normal except low blood sodium. waiting for surgery. His blood test after the minor surgery. Potassium 5.8, chloride 114. co2 32. sodium 130.

He states his B/P went critical high after 9 hours of iv solution

After 2 months seems like Labs are still the same as after surgery He also states he is having cramps and muscle weakness and fluid in lungs

He told them before surgery he had Liddles and ask what was in the iv.

He was told there was NO sodium or Potassium in the iv. When he told about having Liddles the Dr said he didn't miss liddles day at school and he had seen 3 people with Liddles. Since Liddles is truly rare he questioned how the he had found 3.

In the recovery the Dr said he was sorry and he had never seen anything like that. His bp was 208/129 in recovery and a little higher later.

Skeptical Scalpel said...

Since we don't know exactly what the IV solution was, it is difficult to comment on its role as a cause of the postop problem. If there was no sodium or potassium in the IV, it probably was dextrose (sugar) and water.

I can't believe that 1 or even 2 liters of dextrose and water would cause a high BP and electrolyte problems for 2 months.

Disclaimer: I'm not an endocrinologist or a nephrologist.

frankbill said...

If one has Liddles isn't it possible saline infusion might cause some problems. My guess is the Dr thought he knew more then patient and wasn't being up front with patient about what was in IV. That or something went wrong during surgery.

Maybe should add patient was on K sparing diuretic.

frankbill said...

About the lab will usually notice that the specimen was hemolyzed and note it when posting the result. you might find this of interest

Skeptical Scalpel said...

Frankbill, you said there was no sodium in the infusions, Sodium chloride is normal saline. The patient did not receive saline/sodium.

frankbill said...

What I am saying is he was told there was no sodium in the IV.

But he was also told Dr had see 3 others with Liddles With only about 30 family lines know to have the genetic mutation of Liddles worldwide. How likely was that Dr to see 4 people with Liddles?

I would say the Dr wasn't being honest about how many he had seen with Liddles Or truly knew much about it. Was he also not being honest about what was in the IV?

Any way if you would like to find out more about this case just join us and ask any questions.

frankbill said...

This Liddles case shows that there is a need for something like social media. As not many Dr have never seen a case of Liddles but there is at least one Dr that has. Would seem if this Dr would share all the information both good and bad. Maybe it help others that may get to treat someone with Liddles.

Skeptical Scalpel said...

If there was sodium in the IV fluid, the serum sodium should have been high. 130 is abnormally low. 140 is normal.

I agree that a doctor might learn a lot from your group's site, but he would have to at least be aware of Liddle's to join the group in the first place.

frankbill said...

Out of the 1050 that are or have been members of our group there is only one member that has liddles.

What we are about is adrenal causes of hypertension with the main focus on Hyperaldosteronism

Any one that has in interest adrenal causes and treatment of hypertension can learn a lot from our group. All ready Dr Grim has presented some information from this group to the American Society of Hypertension.

frankbill said...

I think there are to many what if's with Liddles to know what any IV fluid will do in Liddles.

I do know that blood sodium of 130 is to low. This may be due over treating Liddles.

Hope said...

Thanks for bringing that up! One of our transplant surgeons is a big fan of this paradigm and when i worked with him as an R2, it just made so much more I almost always use LR, especially in patients with CKD or AKI.

Skeptical Scalpel said...

Just trying to spread the word.

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