Author: Bryan Boling

I'm a critical care nurse practitioner and co-director of the Critical Care APP Fellowship Program at the University of Kentucky. I split my clinical time between the Neurocritical Care Service, the Surgical Critical Care Service, and the ECMO Service. I'm also an Adjunct Faculty Member in the Acute Care Nurse Practitioner Program at Georgetown University. I have a passion for education and #FOAM.

The Pesky Details of Blood Cultures

When I was a bedside nurse – and even before that, when I was a tech in the Emergency Department responsible for drawing blood – the issue of not being able to get two sets of blood cultures, or not getting enough blood in each bottle, would come up. Some patients are very hard to get blood from and blood cultures are a particularly onerous task. We require two separate sticks (often not drawing these from indwelling lines but requiring fresh sticks) and we require a very specific amount of blood in each bottle. This makes getting blood cultures difficult to obtain.

So, why do we need 2 bottles with 10mls each? As usual, Eddy Joe Gutierrez has the answers. He recently released an episode of his Saving Lives podcast where he discusses this. If you prefer to read, he had a blog post back in October of 2020 that covers the same material. As always, he provides links to the studies so you can check his facts. And let’s all be glad that we don’t routinely require three sets.

Tracheoinnominate Fistulas

There are a number of potentially scary complications from tracheostomies, particularly early on in the post-procedure period. Although accidental decannulation and loss of airway is probably the most common, Brandon Oto describes the management of a much scarier complication in the latest in our TIRBO series on the Critical Care Scenarios podcast.

I’ve never experienced one of these (thank goodness), but I have had to rush to the OR with a bleeding ENT patient and they’re some of the scariest scenarios that we encounter in the ICU. I think Brandon is right on when he says that just because the incidence of these types of things is low and the mortality is high doesn’t mean that we should be fatalistic and use that as an excuse not to be prepared for these.

Neuroradiology for Intensivists

I have a particular bias towards neurocritical care. Even though I practice surgical critical care as well, I have an interest in neuro and I think that my practice in neurocritical care has really helped make me a better surgical intensivist as well. Neuro is a weird niche that scares lots of people who don’t do neurocritical care. So, another one of my favorite things is teaching on neurocritical care aimed specifically at non-neurointensivists.

So, I really like this video posted by Dr Casey Albin. Dr Albin is a neurointensivist who is one half of the NeuroEMCrit team and has been a guest on an upcoming episode of our Critical Care Scenarios podcast. She recently did a nice talk covering the basics of neuroimaging aimed specifically at non-neuro intensivists. She covers the basics of reading a head CT (which we’ve covered in detail before, here), CT Perfusion scans, thrombectomy scoring (TICI), how to identify liking cause of intracerebral hemorrhage, and more. I highly recommend it for anyone who wants a good overview of neuroradiology stuff.

Best Vasopressor in TBI?

What vasopressor do you routinely use in the management of traumatic brain injury patients? Admittedly, in my neurocritical care practice, I don’t manage a lot of true TBI patients. In our system, the only neurotrauma patients that come to the neuro ICU are isolated neurotrauma (brain and/or spine without other major trauma). Polytrauma patients go to the trauma service and are comanaged in the TICU along with neurosurgery.

But, in my limited experience, I typically use norepinephrine. I might have formerly said phenylephrine, as that used to be the vasopressor of choice in the neuro ICU. This was mostly due to the fact that at one point, we were mostly using vasopressors to augment BP in order to increase perfusion to the brain or spine, a practice that has largely fallen out of favor. In these cases, the patients often just needed short runs of low dose pressor and so phenylephrine was considered safer to run without a central line, making it appealing in this subset.

But, in the past few years, we’ve gradually shifted away from this to favoring norepinephrine. I think this is largely because we’ve seen a steady increase in the overall acuity of the patients and now those who need pressors typically need them for actual shock, not just to drive MAPs. In that case, central access is typically needed anyway, eliminating the one benefit of phenylephrine.

In this episode of the Elective Rotation podcast, Pharmacy Joe covers a recent study in Anesthesia and Analgesia that seems to favor the use of phenylephrine as the first line vasopressor in TBI patients. It was a rather large retrospective study that showed a statistically significant increase in in-hospital mortality in patients who received norepinephrine as compared to those who received phenylephrine. The study found that norepinephrine was much more common in sicker patients (higher ISS, use of ICP monitoring, comorbidities, etc.), but the authors used propensity-matching statistical analysis to account for this.

Overall, it is an interesting study but there are number of issues including incomplete data regarding shock states. Despite the propensity-matching analysis, I think it’s reasonable to assume that there is probably some bias with patients receiving norepinephrine instead of phenylephrine being sicker at baseline which may account for the difference to a greater degree than is appreciated.

What about you? What is your practice regarding vasopressors in TBI? After reading this study and/or listening to the podcast episode, will you change your practice?

Reading Head CTs

OK, so before I started in neurocritical care, I really didn’t know anything about reading a head CT. I’m not an expert now by any means, but I know the basics and can read an acute head CT pretty well. And, bias aside, I think this is an important skill for a critical care or emergency provider to have. Not to know all there is to know, and not to take the place of our radiology and neurology colleagues, but as a more advanced version of the CXR interpretation skill that every critical care/emergency provider needs.

Head CTs come up not all that infrequently in acute care medicine. There are the obvious examples of acute stroke or head trauma, but a non-contrast head CT is often part of the initial workup for acute mental status changes or inpatient falls. Being able to spot hemorrhages and to have an idea how bad those hemorrhages are (it’s not necessarily related to the size of the bleed) or to be able to rule in or out serious problems can be life saving.

One of my favorite sites on the Internet for all things radiology is Radiology Masterclass. A British site run by consultant radiologists, they provide excellent teaching in the essentials of radiology and offer a number of courses and tutorials. Their tutorial series on CT Brain Anatomy and Acute Brain CT are my go-to sites when I’m teaching students or new providers the fundamentals of Head CTs. They also have a number of good galleries where you can see examples of pathology and normal findings alike.

Liver Function Tests

When I first started in critical care, I got all the various liver function tests (LFTs) confused. Jonathan Downham over at the Critical Care Practitioner, made this great infographic that helps explain which tests tell you what.

And, if you want to go a little more in depth on liver failure, we did a great episode of the Critical Care Scenarios podcast with Elliot Tapper. Dr Tapper goes over everything you wanted to know about liver failure (including why he doesn’t want you to call these tests “liver function tests”).

What Radiology Test Should I Order?

We order a lot of radiology tests in the ICU. But for new providers (and sometimes even those of us with experience), it can be confusing what test I really want. When you order a test, almost every system will have you list the indications, why you’re doing the test. This isn’t actually some administrator micromanaging you and making you justify every test, it helps radiology determine if this is the most appropriate test and helps the radiologist give you a more valuable interpretation.

But, what if you need some help deciding which test to order beforehand? The American College of Radiology has you covered. The ACR has a wonderful tool call the ACR Appropriateness Criteria. This tool requires you to set up a free account, but then you can search for the exam you need. It will tell you the preferred modality (X-ray, CT, MRI, US) and whether or not you need contrast. For a quick reference, the radiologists at Radia have developed this quick reference guide to help their providers decide the best study to order, and they’re good enough to make it publically available.

When to Scope in GI Bleeds

I ran across a great video on Instagram yesterday by one of my favorite GI docs, @docschmidtig. If you’re not already following him, you should, his videos are great! This particular one was funny, but also dealt with an interesting point, why do GI docs wait so long to scope someone with a GI bleed? I liked the video on my IG account, but this morning thought it merited a quick post of its own.

This is something I sometimes get frustrated by (or did until Elliot Tapper set me straight). I’ve got a patient with an obvious GI bleed. I call GI, expecting them to scope and fix the problem. And then it feels like they drag their feet over it. In this video clip, Schmidt explains why.

If you want to delve more into the management of GI bleeding. The aforementioned, always informative Elliot Tapper did an episode of our Critical Care Scenarios podcast not long ago on the subject. Listen here.

PS: If you’re a fan of the TV show M*A*S*H, in episode 4 of season 1, Chief Surgeon Who?, Hawkeye explains a similar rationale to Frank regarding why he’s waiting to operate on the patient in obvious shock.

Reading EEGs

A few days ago, I wrote a post on the use of continuous EEG in the ICU. I mentioned that intensivists should know some of the basics of reading EEGs. I am far from an expert in this. I have learned a few basic things. Mostly what we’re doing at this level with EEG is looking for seizures, specifically subclinical seizures. I think a good way to think of the EEG in this regard is similar to what I first learned about neurocritical care in general. Having come from a cardiac surgery background, an intensivist I worked with said, “think of everything we do in the CTICU, then do the opposite.” Not completely true, but it helped me!

I do something similar with EEGs. I compare them to ECGs. And if they look anything like ECGs, that’s bad. Brain wave activity should be much more random than cardiac electrical activity. So, an EEG that is rhythmic like an ECG is likely to be seizures. At the very least, it’s abnormal. Likewise, flat lines on ECGs represent asystole (bad) and flat lines on EEGs represent the absence of brain activity. Now, sometimes, we want this, as in when we’ve induced burst suppression to help deal with ICP crisis. But, absent that, flat lines on EEGs are usually a bad thing.

Now, of course you can learn a lot more from an EEG than that. If you’re interested in learning more about of EEGs work and the basics of how to read them, Nizam Ahmed has a really nice series of YouTube videos. I think there are about 10 of them in total, but they’re each pretty short and great for microlearning. So, check them out and delve a little more into what the EEG means. And, if you don’t really feel the need to read the squiggly lines yourself, but need some help making heads or tails out of the EEG report, Casey Albin and Neha Dangayach have you covered.

Continuous EEG in the ICU

When I first started in neurocritical care several years ago, I heard Stephan Mayer give a talk on neuromonitoring in the ICU at a conference where he talked about how continuous EEG should be as ubiquitous in the NSICU as continuous ECG monitoring is in the CCU. It made a lot of sense. After all, we don’t manage arrhythmias by looking once and then not again. We don’t assume that because the patient isn’t in a-fib at that exact moment that they won’t be in a-fib at some point (umm…Holter monitors?). But, that’s pretty much what we do with EEG.

At the time, we hardly had any continuous EEG monitoring in our NSICU. Mayer was at Columbia at the time and he proudly proclaimed that their NSICU had the capability to do continuous EEG as part of the bedside monitor package. A few years later, we still don’t have that sort of setup, but we do have a lot of more continuous EEG monitoring. The problem isn’t actually lack of neurologists (although there is a serious lack of neurologists, especially in smaller areas) but a shortage of the technologists and equipment.

In this episode of the CODA Change Critical Care Podcast, Terry O’Brien, a neurologist from Australia makes the case for greater use of continuous EEG use in the ICU and discusses briefly where he thinks this sort of thing is headed. He makes the comparison with echocardiography. A few years ago, it took an echosonographer or cardiologist to get an echo in the ICU. And, while those formal studies are still available and helpful, plenty of us do bedside echos every day in the ICU and are able to get the information that we need. I think that it’s only a matter of time before the ICU nurses are trained to apply EEG electrodes (at least some basic sort of setup) and intensivists are trained to read them (again, in some sort of basic way).

In this way, its comparable to 12-lead ECGs. Any intensivist worth their salt can read a 12-lead ECG. Now, a cardiologist, and especially an electrophysiologist, can obviously get much more information from that ECG than I can. And I think that’s where EEGs are headed. The average intensivist will be able to read an EEG for seizures and maybe some other basics, while an epileptologist can glean much more and could be formally consulted for more info. Speaking of reading EEGs, I’m working on a post about that, so if that interests you, stay tuned.

In the meantime, listen to Terry O’Brien’s talk on continuous EEG in the ICU here.