Trauma Drama

Repeating CT head in Minor Head Trauma—does evidence support this reflexive practice?

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We’re always talking about reducing health care costs.  One of the ways major ways to reduce costs is to stop ordering unnecessary tests.

Let’s talk about CT scans for a minute.

CT scans can cost anywhere from $300-1500 per scan of the body part for your patient, with CT head costs estimated at $600-700.  Now if you include the necessity to scan multiple body parts in a trauma patient, costs can rapidly rise to thousands of dollars.

That cost is monetary, now let’s talk about radiation.  A CT scan of the head is estimated to have as much radiation exposure in one scan as we receive in an entire year of “background radiation” from the earth, 3sV (3 milisieverts).  One scan ultimately carries a very low risk of increasing the additional lifetime risk of fatal cancer, but if you repeat this test multiple times in a patients life, plus add on the additional CTs your patient will be getting… the radiation adds up.

The head trauma debate:

Head trauma is something that all trauma physicians have to quickly become familiar with.  In the ER, we are asked many times to repeat the CT head within 6 hours.  There has been some debate on whether patients need a repeat CT head after minor head trauma. Where minor head trauma is defined as a GCS of 13-15 in association with an intracranial hemorrhage, contusion, subdural hematoma, epidural hematoma or subarachnoid hemorrhage.  In many institutions repeating the scan within 24 hours is the standard of care.  The concern is missing a window of opportunity to intervene when the patient is clinically unchanged, but the bleed has evolved on imaging.  But evidence shows that perhaps these repeat scans are unnecessary…

Let’s look at the research.

R Schuster et al. Is repeated head computed tomography necessary for traumatic intracranial hemorrhage? The American Surgeon 2005 Sep; 71(9):701-4.  This was the first paper out on this topic that I found.  1,462 patients admitted for head trauma were looked at. 255 patients had an intracranial hemorrhage.  Craniotomy was initially performed in 40 patients. Now here’s what we’re interested in: of the remaining 184 patients with ICH who did not warrant an initial craniotomy.  97% (179 of the 184) had a repeat CT head and did not have any craniotomies performed.  5 patients did require craniotomies, but 4 out of those 5 had changes in their neurological examination.  Thus, the conclusion of this study was that there is little utility in repeating the CT head if the neurological exam of a patient does not change.  Exceptions include elderly, defined as age >70 and any patient on anticoagulation/antiplatelet meds or with elevated PT .

Velmos GC, et al. Routine repeat head CT for minimal head injury is unnecessary.  Journal of Trauma. 2006 Mar;60(3):494-9; discussion 499-501.  I’ll jump to the conclusion of this study done at Mass General—179 patients with mild head injury. Of them, 37 showed signs of injury evolution on repeat CT head.  And 7 (4%) required intervention.  All 7 patients had clinical deterioration preceding the repeat CT head.  There were no patients in which the patient had a repeat CT head that changed management before a clinical deterioration.  A GCS less than 15 (13 or 14 in this study), age > 65 years, multiple traumatic lesions found on first heat CT, and interval shorter than 90 minutes from arrival to first CT head predicted worse repeat CT head.  In short, again, the conclusion of this study was that a repeat CT head is unnecessary in patients with mild head injury.

There a few more papers supporting these results:

A prospective evaluation of the value of repeat cranial computed tomography in patients with minimal head injury and an intracranial bleed. Journal of Trauma 2006 Oct;61(4):862-7.

Indications for routine repeat head computed tomography (CT) stratified by severity of traumatic brain injury. J Trauma 2007 Jun;62(6):1339-44.

The role of early follow-up computed tomography imaging in the management of traumatic brain injury patients with intracranial hemorrhage. J Trauma 2007 Jul;63(1):75-82.

**The only study that refuted the conclusion that repeat CT head in mild head injury is unnecessary is the following:

Thomas BW et al.  Scheduled repeat CT scanning for traumatic brain injury remains important in assessing head injury progression. Journal American College Surgeons. 2010 May;210(5):824-30, 831-2.  A study done by the Department of Surgery, University of Tennessee College of Medicine.  This was a retrospective observational study. 887 patients were analyzed.  692 patients had no worsening of repeat CT head scans, of these, 11 eventually had a worsening neurological status requiring intervention.  195 patients had a worsening first repeat CT head, 14 of whom required intervention.  7 worse first repeat CT head patients had a subsequent repeat CT that worsened, leading to an intervention.  A neurological change that preceded an intervention developed in 19 patients.  The study used chi-squared analysis to determined that a worse first repeat CT head was more likely to result in an intervention than if the first repeat CT head was negative, thereby concluding that repeat CT heads remain useful in patients with traumatic brain injury.  It is unclear why this study had such differing results or what the interventions/outcomes were.  The authors do not address this.

The most recent study (very well done if you have a chance to read) on this subject that gained quite a bit of publicity was:  Saleh A. Almenawer et al. The value of scheduled repeat cranial computed tomography after mild head injury. Neurosurgery, 2012; 72 (1).   The conclusion of this paper: “ Although the standard of care in many trauma centers is to schedule a repeat CT within 24 hours for patients with mild head injury and initial scan findings, regardless of the neurological status to rule out secondary changes, our data suggest that this is unnecessary. The meta-analysis did not show statistical evidence supporting the utility of routine follow-up imaging for unchanged or improving patients after mild traumatic brain injury. Considering that this practice is neither risk nor cost free, evidence-based rules should be implemented. Furthermore, we found that the simple yet important neurological examination is the predictive factor of changing the management and guiding the need for repeat imaging after mild head injury.”

So it seems, the repeat CT head may soon be a thing of the past, and onward we go progressing to a more efficient system based on evidence!  (Just keep in mind: nothing replaces the repeat neurological examinations and special cases to consider are the elderly or patients on antiplatelet/anticoagulation therapy.)

 

 

 

 

 

 

The views expressed on this blog are the author's own and do not reflect the views of their employer. Please read our full disclaimer here. Any references to clinical cases refer to patients treated at a virtual hospital, Janus General Hospital.

1 comment for “Repeating CT head in Minor Head Trauma—does evidence support this reflexive practice?”

  1. Ian deSouza
    February 12, 2013 at 6:49 pm

    Nice job. This is yet another example of western medicine replacing clinical evaluation with fancy tests and their associated costs. In the “old days” – even before I was a resident – they just used serial GCS exams. I would bet that serial GCS exams alone would be enough to determine who would need repeat CTs. But, that would mean that someone would actually need to spend some (less reimbursable) time with and examine those patients.

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