All posts by The Trauma Pro

September Trauma MedEd Is Here! Topic: Field Amputation

Welcome to the current newsletter. This one tells you everything you always wanted to know about field amputation (and dismemberment). Here’s the scoop on what’s inside:

  • Indications
  • Who can perform it?
  • What about logistics
  • Equipment
  • Blow by blow about the procedure itself
  • Supplemental resources, include policies, equipment list, and bibliography

Just so you know, subscribers received this issue at the beginning of the month. If you want to subscribe and get it before everyone else, just click here.

Got a suggested theme for later issues? Just let me know what you’d like to read about by replying to this email!

To download the current issue, just click here! You can also enter this web URL directly into your browser: http://bit.ly/TME201609  (All caps! Case is important.)

Thanks for reading!

Predicting VTE Risk In Children

There’s a lot of debate about if and at what age injured children develop significant risk for venous thromboembolism (VTE). In the adult world, it’s a little more clear cut, and nearly every patient gets some type of prophylactic device or drug. Kids, we’re not so certain about at all.

The Children’s Hospital of Wisconsin tried to tease out these factors to develop and implement a practice guideline for pediatric VTE prophylaxis. They prospectively reviewed over 4000 pediatric patients admitted over a 6 year period.

It looks like the guideline was developed using some or all of this data, then tested using regression models to determine which factors were significant. The guideline was then tweaked and a final model implemented.

Here are the factoids:

  • 588 of the patients (14%) were admitted to the ICU, and 199 of these were identified as high risk by the guidelines
  • Median age was 10 (this is always important in these studies)
  • VTE occurred in 4% of the ICU patients, and 10% of the high risk ones
  • Significant risk factors included presence of central venous catheter, use of inotropes, immobilization, and GCS < 9

Bottom line: This abstract confuses me. How were the guidelines developed? What were they, exactly? And the results seem to pertain to the ICU patients only. What about the non-ICU kids? The abstract just can’t convey enough information to do the study justice. Hopefully, the oral presentation will explain all.

I prefer a very nice analysis done at the Oregon Health Science University in Portland. I wrote about this study earlier this year. The authors developed a very useful calculator that includes most of the risk factors in this model, and a few more. Input the specific risks, and out comes a nice score. The only issue is, what is the score threshold to begin prophylaxis and monitoring? Much more practical (and understandable) than this abstract. Check it out at the link below.

Related post:

References:

  1. Evaluation of guidelines for injured children at high risk for VTE: a prospective observational study. AAST 2016, Paper 68.
  2. A Clinical Tool for the Prediction of Venous Thromboembolism in Pediatric Trauma Patients. JAMA Surg 151(1):50-57, 2016.

Confusion At The Trauma Professional’s Blog?

Many readers may have noticed that the blog site has looked different for the past week. The good news is that I’ve migrated all my content (and more) to a standalone website, TheTraumaPro.com.

But the bad news was that all of the search engines only know of the original site, regionstraumapro.com, the original blog hosted on Tumblr. So a lot of people ended up being directed to an old post (on the new site) and not knowing why or how they got there. Confusing! Furthermore, links to related posts on the Tumblr site took readers to the same old random post on the new site. Even more confusing!

In order to stem the confusion while the search engines catch up, I’ve decided to run both sites in parallel. All posts will be cross-posted to both sites simultaneously. The Twitter notification will link to the post on the new site, but it will still be on Tumblr as well.

Please check out all the extra content on the new site at:

TheTraumaPro.com

but just be aware that searches for content will probably direct you to Tumblr at:

regionstraumapro.com

Thanks for reading, whichever one you choose!

Michael

Cervical Spine MRI After Negative CT

dislocation-atlanto-axial-0005

There are multiple ways to clear a cervical spine! Most centers use a combination of clinical decision tools and CT scan in adults. The gold standard tie breaker, warranted or not, seems to be MRI. This tool is only used in select cases where conventional imaging is in doubt, or the clinical exam is puzzling.

Some centers clear based on CT only as long as imaging is indicated. Some use MRI in cases where patients continue to complain of midline neck pain or tenderness after negative CT. A multi-center trial encompassing 8 Level I and II centers prospectively performed MRI on patients who could not be clinically evaluated, or had persistent midline cervical pain after normal CT.

A total of 767 patients were seen over a 30 month period. Besides looking at the usual data points, the authors were interested in new diagnoses and changes in management based on the MRI results.

Here are the factoids:

  • Neck pain and inability to evaluate occurred with equal frequency, about 45%; the remaining 10% had both
  • 23% of MRIs were abnormal, with 17% ligament injury, 4% swelling, 1% disk injury, and 1% dural hematomas.
  • Patients with normal and abnormal MRI had neurologic anomalies about equally (15-19%). [Why are these patients included? Were they initially not evaluable?]
  • The cervical collar was removed in 88% of patients with normal MRI (??), and in 13% with abnormal MRI
  • After (presumably) positive MRI, 14 (2%) underwent spine surgery; 8 of these had neurologic signs or symptoms

Bottom line: I’m a bit confused. If the authors were really trying to figure out the rate of abnormal MRI after negative CT, they should have excluded the patients with known neurologic findings. These patients should nearly always have an abnormal MRI. And why did they not take the collar off of the 12% of patients with both normal CT and MRI??

Hopefully, details in the presentation next week will help explain all this. I suspect that the study will show that there are cases where CT is normal but MRI is not. The abstract does not clearly describe how many of these are clinically significant.

I admit, I’m not very comfortable clearing the cervical spine in a patient with negative CT (even if read by a neuroradiologist) and obvious midline neck pain/tenderness. I hope this study helps clarify this issue. We shall see…

Reference: Cervical spine MRI in patients with negative CT: a prospective, multicenter study of the research consortium of New England centers for trauma (ReCONECT). AAST 2016, Paper 61.

Early Operative Fixation of Pelvic Fractures And Functional Outcome

Disruption of the pelvic bones takes a huge amount of energy, and results in significant bleeding and morbidity from other causes. Repair typically consists of surgical fixation, frequently with temporary external fixation in the interim. These patients require intensive therapy postoperatively, with inpatient rehab prior to discharge home.

How well do patients with severe pelvic fractures do in the longer term? The group at the University of Tennessee in Memphis did a lengthy followup study spanning 18 years of severe pelvic fractures treated at their hospital. These patients had sustained fractures with significant bleeding, an open book component, or SI joint disruption with vertical shear.

open book pelvis pre

The authors used phone interviews and a standardized measurement instrument (Activity Measure for Post-Acute Care, AM-PAC) to gauge daily activity of affected patients. They then looked for factors predictive of functional outcome.

Here are the factoids:

  • 401 patients were identified over the 18 year study period
  • Of these only 71% survived (285), and the study documented followup in 145 (51%)
  • Average ISS was 27 (fairly high) and patients tended to be older (mean 53 years)
  • Even after 8 to 20 years, mobility and activity were significantly impaired as measured by AM-PAC
  • Time to fixation was the only identifiable factor that had an impact on decreased mobility or activity

Bottom line: Early definitive fixation of the pelvis was the only variable found that had an impact on future mobility and activity. Frequently, external fixation is applied soon after admission. But remember, your trauma patient is at their healthiest as they roll through the doors of your ED. The sooner they get all of their problems fixed, the better (and safer).

Impact of early operative pelvic fixation on long-term functional outcome following sever pelvic fracture. AAST 2016, Paper 60.