Tag Archives: TBI

What Happens To Your Average Subarachnoid Hemorrhage?

Management of traumatic brain injury (TBI) is a common issue faced by trauma professionals. And isolated subarachnoid hemorrhage (SAH) is one of the more common presentations. In many centers, this diagnosis frequently results in admission to the hospital, neurosurgical consultation, and repeat imaging.

Is this too much care? We adopted a practice guideline nearly two years ago based on our own clinical experience that eliminated the last two. Patients were still admitted for neurologic monitoring for 16 hours. But is even this too much?

What we really need is a better understanding of the natural history of uncomplicated traumatic SAH. Well, a study from Sunnybrook and the University of Toronto does just that. They performed a 17 year meta-analysis of the literature on isolated SAH with mild TBI (GCS 13-15). They pared their initial literature search of nearly 2900 studies down to the usual few, 13 in this case. All but one were retrospective, of course, and they had the usual design flaws.

Here are the factoids:

  • How many patients eventually needed neurosurgical intervention?  0 (Well, almost zero. It was 0.0017%, to be exact.)
  • How many had progression of the SAH? About 6%
  • How many had neurologic deterioration? 0.75%, which included two  patients with increased headache and one with some confusion. Two developed intraparenchymal hemorrhage (one was on anticoagulants)
  • How many died? Only 1 died from neurologic causes, and that patient was anticoagulated at the time of injury.

Bottom line: It looks like we may be overdoing it for patients with isolated SAH and mild TBI. The natural history seems to be fairly benign, unless the patient is taking anticoagulants. The type of drug was not specified, so warfarin, aspirin, clopidogrel, and the newer anticoagulants should all be included.

Perhaps it’s time to update the our practice guidelines further. It looks like most of these simple, isolated SAH can be evaluated and released. However, if the GCS is 13 or 14, they should still be admitted for monitoring for a short period. And if on anticoagulants, admission with a repeat CT is in order.

Related posts:

Reference: The clinical significance of isolated traumatic subarachnoid hemorrhage in mild traumatic brain injury: A meta-analysis. J Trauma , published ahead of print, July 8 2017.

Could There Be A Simpler GCS?

The Glasgow Coma Scale (GCS) has been around forever. Or really, for about 45 years. It was actually developed in the early 1970s and known as the Coma Index. It was further refined into the GCS, when 1 was selected as the minimum component score. Ever since, it has been used as a common language among clinicians to communicate gross neurologic function and trends.

But it is still somewhat complicated. Oh no it’s not, you say? Then why do so many trauma resuscitation rooms have it posted on the wall? There are three components, each with a different number of possible values. And frankly, some are harder to remember than others. Decerebrate vs decorticate, right?

So what if someone told you that a single GCS component works just about as well as the whole bunch? Researchers have been piecing this together for years, focusing on the motor component of GCS (mGCS). There are two flavors of simplified score: mGCS and Simplified Motor Score (SMS). The mGCS is just what it sounds like: the full motor component of GCS, ranging from 1-6. The SMS is further simplified from the mGCS: mGCS of 1-4 tranlsates to SMS 0, mGCS 5 = SMS 1, and mGCS 6 = SMS 2. In my opinion, this is actually more complicated because you have to remember not only the 6 mGCS levels, but also the cutoffs to convert it to SMS.

Finally, a group from Oregon Health Sciences University in Portland performed a nice meta-analysis of the best individual studies.

Here are the factoids:

  • Only papers that compared total GCS (tGCS) to mGCS or SMS were included, and only if they analyzed a receiving operator characteristic curve. The statistics appeared sound.
  • tGCS was very slightly better than either mGCS or SMS at predicting:
    • in-hospital mortality
    • neurosurgical intervention
    • emergency intubation
    • severe TBI

Bottom line: Overall, the total GCS is slightly (just a few percent) better at doing the things listed above, compared to the motor score alone or the “simplified” (really?) motor score. Is this clinically significant in the field? Probably not. And its mere simplicity makes it appealing. 

However, there is one major problem to adopting the mGCS for use outside the hospital. Inertia. As I mentioned, we have been using the full GCS score for almost 50 years. Pretty much every trauma professional is familiar with the GCS or knows where to look up the details. But I suspect that those clincicians who assume care of the patient once in the hospital, and especially the intensive care unit (neurosurgeons) will never allow the use of an abbreviated scale. Good idea, but sorry, it won’t catch on in the real world.

Do We Really Need To Consult Neurosurgery For Mild TBI?

We consult our neurosurgeons too often. Think back on all the head injured patients you have admitted and placed a neurosurgical consult. How many times did they recommend something new or different, or take them to surgery? Not very often, I would guess.

This is becoming a hot topic. Check out the references below to read about a few other studies that have taken a similar approach.

The trauma group at Scripps Mercy in San Diego retrospectively reviewed their admissions to determine how often patients with mild TBI (GCS > 13) and some degree  intracranial hemorrhage required neurosurgical intervention, even if they were intoxicated or taking anti-platelet or anticoagulant drugs. A total of 500 patients were studied over a 28 month period.

Here are the factoids:

  • 49 (10%) of patients required some sort of neurosurgical intervention (41 craniotomy/craniectomy, 8 ICP monitors)
  • 93% of patients had neurosurgical consultation, and made additional recommendations in only 10 (2%),none of which changed management
  • There was no clinical difference in GCS between those who received an intervention and those who did not
  • Epidural and subdural hematomas were significant predictors of neurosurgical intervention
  • Intoxication or use of anti-platelet or anticoagulant drugs was not associated with intervention. These were present in 30% of all patients!
  • Unsurprisingly, ICU and hospital length of stay were longer in patient who underwent an intervention

Bottom line: As I said, this seems to be a hot research topic. And in this study, the numbers are getting larger and the criteria more inclusive (alcohol and anticoagulants allowed).

Neurosurgeons play a very important role in patients with more moderate to injury to their brain, and with spine injuries. But their input may not be needed in many patients with milder injuries. These data suggest that, in patients with GCS > 13, only subdural and epidural hematomas require consultation because they are much more likely to require intervention. 

This parallels a practice guideline we have in place where patients with subarachnoid or small intraparenchymal hemorrhage, or a linear skull fracture are managed by the trauma service without neurosurgical consultation. We do involve them if there is any intracranial hemorrhage with a history of anticoagulant use, however.

We all need to use our neurosurgeons wisely, and this paper helps to clarify situations where they may and may not be needed. 

Related posts:

Reference: Routine neurosurgical consultation is not necessary in mild blunt traumatic brain injury. J Trauma 82(4):776-780, 2017

Diagnostic Tip: Nail Discoloration After Severe TBI

Occasionally, patients who have had a severe brain injury but recovered relatively quickly may present with complaints of odd nail discoloration. This may involve fingernails and/or toenails. What gives?

This is actually a byproduct of repeated exams to determine the Glasgow Coma Scale score. A common way to determine the motor component is to squeeze the fingertip or toetip. I’ve seen some neurosurgeons use a pen to apply a great deal of force to the nail.

The discoloration is a resolving subungual hematoma. You may see different colors under different nails, depending on the age of the hematoma. Amaze your colleagues with your knowledge on this one!

Everything You Wanted To Know About: Cranial Bone Flaps

Patients with severe TBI frequently undergo surgical procedures to remove clot or decompress the brain. Most of the time, they undergo a craniotomy, in which a bone flap is raised temporarily and then replaced at the end of the procedure.

But in decompressive surgery, the bone flap cannot be replaced because doing so may increase intracranial pressure. What to do with it?

There are four options:

  1. The piece of bone can buried in the subcutaneous tissue of the abdominal wall. The advantage is that it can’t get lost. Cosmetically, it looks odd, but so does having a bone flap missing from the side of your head. And this technique can’t be used as easily if the patient has had prior abdominal surgery.

2. Some centers have buried the flap in the subgaleal tissues of the scalp on the opposite side of the skull. The few papers on this technique demonstrated a low infection rate. The advantage is that only one surgical field is necessary at the time the flap is replaced. However, the cosmetic disadvantage before the flap is replaced is much more pronounced.

3. Most commonly, the flap is frozen and “banked” for later replacement. There are reports of some mineral loss from the flap after replacement, and occasional infection. And occasionally the entire piece is misplaced. Another disadvantage is that if the patient moves away or presents to another hospital for flap replacement, the logistics of transferring a frozen piece of bone are very challenging.

4. Some centers just throw the bone flap away. This necessitates replacing it with some other material like metal or plastic. This tends to be more complicated and expensive, since the replacement needs to be sculpted to fit the existing gap.

So which flap management technique is best? Unfortunately, we don’t know yet, and probably never will. Your neurosurgeons will have their favorite technique, and that will ultimately be the option of choice.

Reference: Bone flap management in neurosurgery. Rev Neuroscience 17(2):133-137, 2009.