Showing posts with label lactic acidosis. Show all posts
Showing posts with label lactic acidosis. Show all posts

Thursday, November 14, 2019

Lactate Measurements: Venous or Arterial Samples?

This is a question I remember asking myself quite a bit during my training when I used to check/trend lactate levels more than I do today. Does it really matter whether I check it from an arterial line or from a venous stick?

This study which was a prospective study of 100 patients who had both an arterial line and a central line. The authors compared the values during resuscitation. Short answer is no, there's no statistically significant difference.

Does this reflect the real world? Not really. As much as I would like to have an arterial line in all of my septic shock patients, this does not necessarily happen right away. Arterial lines, even for me who has put in hundreds, is not the easiest of procedures. I actually failed miserably on a patient in 5 different sites several weeks ago. I have excuses but I won't share them ;). Also, it is time consuming and causes the patient discomfort. That being said, when someone is sick sick, they get an arterial line from me or my trusty badass RT's.

The other real-world concern is the central line issue. There's data out there that you don't necessarily need a central line to run vasopressors, some of that data is my own data (my ONLY data out there haha). That being said, these patients will have their venous lactate checked via a peripheral stick, in many cases using a tourniquet. Using a tourniquet has its own problems as that could make the lactate levels unreliable.

Now, let's say that you have both an arterial line and a central line, then you can use this data more appropriately. Sort of. The authors did not specify whether they used the same point-of-care device to check the lactate levels in the venous nor arterial values. You know, some shops use POC for arterial, some have the fancy machine inside the ICU. Some could run the venous blood in that fancy machine, the POC, and some shops have to send it downstairs to the lab. This was not specified. Sigh.

Either way, I need to dissect the data regarding tourniquets for you.

-EJ



Link to Abstract

A. Mahmoodpoor, K. Shadvar, S. Sanaie, et al., Arterial vs venous lactate: Correlation and predictive value of mortality of patients with sepsis du..., Journal of Critical Care, https://doi.org/10.1016/j.jcrc.2019.05.019

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.

The primary source of compensation I receive for this page and Instagram work is via Amazon Affiliates. All this free education you receive is much out of the kindness of my heart but I also like to receive a check every month from Affiliate Marketing. No one likes to work for free. The best part is that it's of no cost to you. Here's how it works.
You click on the link for Will Owens' awesome ventilator book here: https://amzn.to/2myFxYm and whether or not you purchase the book I receive a small commission for whatever you buy on Amazon for the next 24 hours at no cost to you. For every copy of the Ventilator book people have bought off of my affiliate links, for example, I have earned $0.85. I know it's not big money but it helps motivate me to keep on plugging along doing this heavy lifting in Critical Care. Thank you for supporting my work!
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Wednesday, November 13, 2019

Lactic Acidosis has a WIDE Differential (not just Sepsis)

There's a pendulum in medicine. Some things are over recognized and aggressively treated, some things are under appreciated (like subtle decreases in serum bicarb showing that the patient is becoming more acidotic and no one notices because the patient has obesity hypoventilation syndrome and their baseline bicarb is 34 and now has a bicarb of 22 and they look like poop).

At this time, all the rage is serum lactate and lactic acidosis. Every time someone says those words, with my biochemistry knowledge lagging far behind, everyone thinks "SEPSIS!! 30cc/kg IVF STAT!!!!" If you all knew how much this upsets me whenever I see it, you'd wonder how I'm still alive because I see it all the time. I bet you see it at your shop, too. It's very common because the pendulum has swung too far.

In order to correct this, I have embarked on discussing this topic ad nauseum in one of my lectures for Hawaii/Portland in 2020. The article linked below from the New England Journal of Medicine has a table that has been reproduced in many different forms. I will not break down the pathophysiology of each one of the etiologies, but I have been called for an ICU transfer for MANY of these.

Here are some examples where I have been called over the years where patients have received 30cc/kg of saline w/stable vital signs:
1. COPD patient receiving albuterol nebs. Lactic acid elevated because they're A. huffing and puffing, and B. receiving beta-2 agonists.
2. s/p seizure patients who are post-ictal
3. hypoglycemic diabetics
4. leukemia patients just watching TV
5. cocaine/chest pain patients in the ED
6. cardiogenic shock patients on an epinephrine gtt
7. HIV pt on Stauvidine (I should have written this one up)

I'm obviously not getting into the different subgroups of lactic acidosis at this time. Let's walk together before we run. Our job is to fix the underlying cause of the lactic acidosis, not dilute the number down with fluids.

-EJ




Link to Abstract

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.

The primary source of compensation I receive for this page and Instagram work is via Amazon Affiliates. All this free education you receive is much out of the kindness of my heart but I also like to receive a check every month from Affiliate Marketing. No one likes to work for free. The best part is that it's of no cost to you. Here's how it works.

You click on the link for Will Owens' awesome ventilator book here: https://amzn.to/2myFxYm and whether or not you purchase the book I receive a small commission for whatever you buy on Amazon for the next 24 hours at no cost to you. For every copy of the Ventilator book people have bought off of my affiliate links, for example, I have earned $0.85. I know it's not big money but it helps motivate me to keep on plugging along doing this heavy lifting in Critical Care. Thank you for supporting my work!
- My Amazon Store