Be careful with Ketamine and Catecholamine-dependent Heart Failure

The Ketamine kick continues! I am not going to pretend I knew everything about everything as I've created this page over the last several months. People who walk around saying things like they were born with that knowledge sometimes need to be checked. We all had that one eye-opening day where it was like, "(explicative) I should have known that!"

I had some basic knowledge on ketamine but fortunately I have expanded that substantially over the course of working on my lectures. The whole "negative ionotrope" concept was something I was familiar with, but I never actually looked up in depth until colleagues such as the great Seiha Kim, David Convissar, and other great anesthesia colleagues who have more experience on the matter than I do. Not to mention that Seiha is both a pharmacist and an anesthesiologist.

A healthy heart should not have any issues with ketamine for sedation nor rapid sequence intubation, but, as mentioned in the Christ article linked, you can find a 21% decrease in cardiac index. This also brings me to the point where many clinicians focus on the blood pressure while ignoring the patients cardiac index/cardiac output. It makes us feel all warm and fuzzy inside to see the MAP > 65 as we keep on increasing our pressors but at the same time we have NO IDEA what this afterload increase is doing to the LV. We feel self-reassured but really our patients are going on a downward spiral. That's a discussion for another day. We really need more than a BP cuff or an a-line to get a true grasp of what's going on with our critically ill patient who is otherwise hemodynamically unstable.

-EJ

Link to Abstract

Christ G, Mundigler G, Merhaut C, Zehetgruber M, Kratochwill C, Heinz G, et al. Adverse cardiovascular effects of ketamine infusion in patients with catecholamine-dependent heart failure. Anaesth Intensive Care. 1997;25:255–259.

Link to Abstract

Bovill JG (2006). Intravenous anesthesia for the patient with left ventricular dysfunction. Semin Cardiothorac Vasc Anesth 10: 43–48.

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.

Ketamine + Morphine

Link to Abstract

Jennings PA, Cameron P, Bernard S, Walker T, Jolley D, Fitzgerald M, Masci K: Morphine and ketamine is superior to morphine alone for out-of-hospital trauma analgesia: a randomized controlled trial. Ann Emerg Med. 2012, 59: 497-503. 10.1016/j.annemergmed.2011.11.012.

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.

Ketamine: Mechanism of Action

Link to Abstract

Link to FULL FREE Article

K Hirota, D G Lambert, Ketamine: its mechanism(s) of action and unusual clinical uses., BJA: British Journal of Anaesthesia, Volume 77, Issue 4, Oct 1996, Pages 441–444.

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.

Ketamine Continuous Infusions for Sedation in the ICU

One of the lectures I’m working on is regarding minimizing opioid utilization in the ICU on our critically ill patients on mechanical ventilation.

I honestly do not use ketamine as often as I’d like and I have been reviewing all the data behind continuous infusions over the last two days.

Unfortunately, the data isn’t incredibly robust (small sample sizes, mostly retrospective, heterogenous non-MICU patient populations) and there is a wide variation in the doses used in the different studies. This study published earlier this year used ketamine in conjunction with other agents, mostly propofol or fentanyl. The authors found that using ketamine decreases the doses the other agents with no changes in all the other outcomes. Most clinicians are looking for miracle drugs rather than incremental (albeit small) improvements here and there.

One of the problems I have with ketamine is, depending on how it’s mixed, is the sheer volume of the drip. I try to keep my patients potato chip dry and if the ketamine is basically a maintenance fluid, I’m not going to be as excited about it. 

Do you all use ketamine in your ICU for continuous sedation? Do you use it as monotherapy or with other infusions?



Link to Abstract

Garber, P. M., Droege, C. A., Carter, K. E., Harger, N. J. and Mueller, E. W. (2019), Continuous Infusion Ketamine for Adjunctive Analgosedation in Mechanically Ventilated, Critically Ill Patients. Pharmacotherapy, 39: 288-296.

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.

Ketamine for Rapid and Delayed Sequence Intubation

Alternatives to Rapid Sequence Intubation: Contemporary Airway Management with Ketamine

What are your experiences with ketamine for intubations?

I am really glad that I stumbled onto this article that was shared by @the_resuscitationist and @medicotactico.

When you're dealing with airways and medications that have can concerning adverse effects, you really shouldn't trust me on anything and should read the article yourself. Link in bio. This one is also completely free! Also, everything I typed for this post didn't fit in the space allowed by IG, so if you want to finish reading all my thoughts, you have no choice but to head over to my website. It is what it is and this article got me fired up!

For my physicians/NP/CRNA/PA colleagues who manage airways: How do you utilize ketamine for these situations?

For my ICU and ED nurses who push this medication: what have been your experiences with it?

The first thing the authors state is something those of us in the ICU or ED’s already know, establishing an airway is the riskiest commonly performed procedure in acute care. I do not proceed with pushing meds unless I have all my ducks in a row and I have plan A, B, and C easily accessible.

Here’s what happens with ketamine versus other agents that are commonly used: the patient becomes dissociated, they get that glassy look in their eyes, basically disconnected, but the brain stem reflexes stay intact... well... most of the time. You need to be prepared for it to hit the fan at any time. The patient should continue to breath spontaneously. The patients hemodynamics should also be augmented. Again, the key word is “should”. I’ve seen patients become apneic as well as hypotensive but more on that later. I’m just glad I’m not the only one who has seen these effects which are described in the literature. Nurses, don’t push ketamine like a bolus. Push it over 30-60 seconds. I know there’s a ton of adrenaline rushing in those rooms and you're used to pushing meds.

Here’s a strategy I learned from this article. Go ahead and push the ketamine when the patient is agitated and thrashing to allow for preoxygenation. The patient should chill out and when they cease thrashing, one can move forward with a preoxygenation strategy. They even explained certain cases where patients were provided with ketamine for this reason and then didn’t even need intubation.

What’s the dose? 1-2mg/kg of IDEAL body weight.

One of the things that I have noticed clinically when administering ketamine to establish and airway is the clenched jaw. Here, the authors recommend using midazolam, propofol, or even a sub-induction dose of etomidate. Just be aware that these agents bring their own baggage to the party.

Here's what the authors say about the hypotension related to ketamine. First, you need to know whether you think the patient is catecholamine depleted. In other words, they are in shock and they are running out of steam. Those patients should be resuscitated to the best of your ability and you may have to cut the dose in half. Again, read the article for yourself.

Lastly, the authors discuss using ketamine for sedation but it should be kept at dissociative doses or else your patient is going to have some no-so-good experiences. You may need to add some propofol at that point.

For respect of the authors, I will stop there. Read it for yourself. Again, it's free! Thank youuuuu!

- EJ





Link to Article

Link to FREE PDF

Merelman, A., Perlmutter, M., & Strayer, R. (2019). Alternatives to Rapid Sequence Intubation: Contemporary Airway Management with Ketamine. Western Journal of Emergency Medicine, 20(3), 466–471.

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.