Head Trauma

With head trauma you have to worry about the primary injury, from the blunt trauma itself, and about secondary injuries, from the swelling, edema, and neurotoxin release. So for a quick how to on organizing your worry, keep reading!

Who to scan?

There are three different criteria in common use for deciding who to send to the scanner. Canadian, Nexus and New Orleans. All are very sensitive, with varying levels of specificity. Pick your poison. Talk to your friends, make a decision. You don’t need to stick to just one for the rest of your life, but I’ve heard tell it’s better to be consistent than not medical-legally speaking. But be mindful, all three kick out kids (use PECARN) and elderly ( JUST SCAN.) 

While we are talking about scanning: as it turns out 75% of basilar skull fractures have temporal bone fractures. (Wennmo and Spandow)  If a patient presents with signs or symptoms concerning for Basilar skull fracture go ahead and get dedicated temporal CTs as well for adequate views of these bones. 

What are you scanning for?

There are four main types of intracranial bleeds that we’ve all heard several times. 

Going from the outside in, first comes Epidural hematomas. These brisk arterial bleeds will appear lens shaped in CT, as the bleeding is being kept into position by suture lines.

Image result for epidural hematoma

Lens shaped bright blood and positive arrow sign. https://www.med-ed.virginia.edu/courses/rad/headct/trauma7.html

This means that a lot of pressure can develop on the brain. Commonly called the “talk and die”, these are famed for a Lucid interval between the event ( +/- LOC at the time) and the point when the brain can’t take the pressure * insert Bowie and Mercury masterpiece combo pop hit here*.  These patient’s can have wonderful recoveries if they go to the OR for evacuation soon.

If you are working out in the sticks with not a neurosurgeon to be found… Get out that burr hole kit!  If you want some hair raising shivers, here is a great, fast article from ACEP describing a case and a quick how to: https://www.acepnow.com/article/perform-emergency-burr-hole-procedure/ 

Image result for subdural hematoma

https://www.clinicaladvisor.com/home/features/clinical-challenge/case-study-a-subdural-hematoma-after-a-fall/

Just under the dura stretch a bunch of tiny vessels. When these get shaken or stirred, you get a classically crescent shaped subdural bleed. These can have a much longer lasting impact, as the blood directly touches the brain parenchyma, therefore releasing more neurotoxins and worsening outcomes. The way I keep these two straight is- if I was walking around Chicago and got bonked on the head- I’d prefer an epidural bleed. But if I was out practicing good work life balance techniques and was out hiking in the mountains- I’d prefer a subdural, in chances that I might stay alert enough,  long enough to be treated. AKA be careful because Subdural hematomas can be very subtle in symptoms- especially as they more commonly happen in the elderly- if a family member thinks that they are acting differently and are unsure about falls – don’t be shy about getting that CT. That being said – call the neurosurgeon and admit to the neuro ICU because this patient will need close monitoring for those secondary injuries that I mentioned above. 

Traumatic subarrachnoid hemorrhages are not AS worrisome as spontaneous SAH, as they have less risk of rebleeding and vasospams. However, the blood can clot up CSF tracts leading to hydrocephalus. Care of traumatic SAH in the ER will vary greatly depending on size and protocols. 

For all of these bleeds, anticoagulation reversal will likely depend on the size of the bleed. Talk with your neurosurgeon about your best options. Vitamin K + KCentra for warfarin works well, but it may take several hours for full effect- so consider giving blood products. The *gabitran taking patients may benefit from some PCC. I suggest talking to your local friendly pharmacist or following hospital protocols. 

Small hemorrhages at gray-white interface http://learningradiology.com/archives2008/COW%20315-Diffuse%20Axonal%20Injury/daicorrect.htm

In this image, you may think that this patient will be fine- just small punctate bleeds. But this common CT in head trauma can come with the diagnosis with the highest morbidity – Diffuse Axonal Injury.  Common from high accel/decel or rotational injuries- this patient will likely be in a coma like state. And most unfortunately, as of yet, there is nothing that we can do. 

Seconday Injuries

Another downer, there is nothing that has been shown to help decrease neurotoxin release or their effect. However, there are some things that we can do to help with the swelling that can occur. 

Swelling in the brain can leadsto herniation, if a patient’s mental status is deteriorating and your are concerned for hernation- get the anti-swell ball rolling. Mannitol is our first option that we prefer at Rush. But as this is an osmotic diuretic – you will want to avoid in patients with ESRD and will want to be careful in hypotensives. Instead consider hypertonic saline. 

If ventilated, the old hyperventilate answer from my med school exams is no longer the answer. Keep the CO2 in a normal range. If you are very very very concerned for herniation, you can try hyperventilation as a last ditch effort- but only do it for a short amount of time ( maybe 30minutes.)

Consider anticonvulsants. And consider them strongly if they begin seizing, the most strongly, aka given them some Lorazapam.

Definitely do not given steroids. This has been shown to actually worsen mortality. 

Less than 8, Intubate!

I won’t get into my feelings on the GCS scale. But we all know to intubate when patient’s can no longer protect their airway. Many of these significant head trauma patient’s will fit that shoe. As we definitely do not want to trigger their sympathetics- premedication in these patients is key. Consider high dose fentanyl (2-4mg/kg) about 5 minutes before intubation.

When it comes to sedation, do it.

And remember that BP is very important as we do not want to starve the already suffering brain of precious oxygen. Consider more hemodynamically stable medications like Ketamine or Etomidate.

As for Rocc v. Succ: Rocc will be rough with the 40min paralysis if your neurosurg friend is almost there, but this extra time might be nice for you perform other procedures and or imaging. But do not forget to give extra sedatives while they are in this paralyzed state. Succ is faster on and off, but there is some data suggesting that it might have higher mortality in brain bleed patients. (Patanwala et al.) 

Conclusion

All in all, you will be seeing a lot of blunt head trauma, much of which will require CT. Most of these patients will be safe to go home. But when they aren’t safe for home… they really aren’t safe for home. 

Image result for asterix comic tongue

In case you are wanting more practice judging head trauma – in 2011 a group anaylzed   risk factors for  traumatic brain injury  in the Asterix comic books. Find it in Pubmed or on the web. Science!   https://www.booktrust.org.uk/book/a/asterix-the-gaul/

  1. Wennmo C, Spandow O. Fractures of the temporal bone—chain incongruencies. Am J Otolaryngol. 1993 ; 14(1):38-42.
  2. Patanwala, A. Erstad, B. Roe, D. Sakles, J. Succinylcholine Is Associated with Increased Mortality When Used for Rapid Sequence Intubation of Severely Brain Injured Patients in the Emergency Department. Pharmacotherapy. 2016; 36(1): 57-63

Posterior Circulation Ischemic Strokes

Last week we had the opportunity to learn about posterior circulation ischemic strokes from vascular neurologist, Dr. Osteraas.

Diagnosing posterior circulation ischemic strokes can be challenging in the emergency department, largely because posterior circulation ischemic strokes frequently lack “traditional” stroke signs and symptoms and the symptoms that you do see are often non-specific and can be slow onset. Despite this, it is important to do our best to diagnose these as about 20% of ischemic events involve the posterior circulation and posterior circulation ischemic strokes can lead to some of the most devastating neurologic outcomes, including massive cerebellar infarcts with subsequent herniation and locked in syndrome.