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Trauma Mortality: The New Nomenclature – Part 2

Yesterday I tried to clarify the most commonly assigned type of trauma mortality, anticipated mortality without opportunity for improvement (AMW/OOI). Today, I’ll cover another, and I’ll finish the series on Monday.

Old nomenclature: potentially preventable death
New nomenclature: anticipated mortality with opportunity for improvement (AMWOI)

Again, these sound somewhat similar but they are quite different. Potentially preventable death used to be applied to patients who had obvious care issues that had some potential to change outcome. But it also contained a number of patients discussed yesterday who had support withdrawn due to age or degree of injury. There was some nagging doubt that, it something else had been done, maybe they would have recovered. So several of the “potentially preventable” deaths in the old category have been moved to the “without opportunity for improvement” category.

Unfortunately, a larger group of patients from the nonpreventable death category have moved into the “with opportunity for improvement” category. This is actually a good thing, though. The AMWOI category looks at whether there were any care issues, regardless of whether support was eventually withdrawn.

Whereas the vast majority of deaths at any center should fall into the AMW/OOI category, a modest number will be classified as AMWOI. The actual number depends on how broadly or narrowly an opportunity for improvement is defined. If you consider a few areas of missing documentation on the trauma flow sheet an opportunity for improvement, then you’ll have a lot of deaths classified this way. Concentrate on issues that might have actually had an impact on the outcome. The key is to develop a set of criteria that is realistic and that work for you. If the number of AMWOI deaths seems high, go back and look at those criteria and adjust them. You can still work out a system for improving trauma flow documentation without it changing every death in a trauma activation to one with an opportunity for improvement.

Monday, I’ll finish up with a few words on unanticipated mortality.

Related posts:

Trauma Mortality: The New Nomenclature

The American College of Surgeons adopted a new naming convention for trauma deaths last year. Of course, anytime you change something up, there will be some confusion. I’m going to compare old and new and give some of my thoughts on the nuances of the changes.

Old nomenclature: Nonpreventable death
New nomenclature: Anticipated mortality without opportunity for improvement (AMW/OOI)

They seem similar, right? But the new name takes into account a growing phenomenon: elderly patients (or younger ones for that matter) who sustain injuries that might be survivable, but are devastating enough to cause the family to withdraw support. Technically, the deaths could be preventable to some degree, but the family did not wish to attempt it. The new system recognizes that it is an expected outcome due to patient or family choice.

There are several key points to handling AMW/OOI. First, if your center is providing great care, the majority of your deaths should be classified this way. Every one of them needs some degree of review, whether from just the trauma medical director and/or program manager or via the full trauma PI committee. However, your full PI committee needs to at least see a summary of the death if it’s not discussed in full.

How to decide on abbreviated review and report vs discussion by full committee? It depends on your trauma volume, and program preference. Higher volume centers do not usually have the luxury of discussing every case due to time constraints.

Tomorrow I’ll discuss the next type of trauma mortality, aniticipated mortality with opportunity for improvement, and I’ll finish the series on Monday.

Related posts:

How Much Radiation is the Trauma Team Really Exposed To?

Okay, so you’ve seen “other people” wearing perfectly good lead aprons lifting them up to their chin during portable xrays in the trauma bay. Is that really necessary, or is it just an urban legend?

After hitting the medical radiation physics books (really light reading, I must say), I’ve finally got an answer. Let’s say that the xray is taken in the “usual fashion”:

  • Tube is approximately 5 feet above the xray plate
  • Typical chest settings of 85kVp, 2mAs, 3mm Al filtration
  • Xray plate is 35x43cm

The calculated exposure to the patient is 52 microGrays. Most of the radiation goes through the patient onto the plate. A very small amount reflects off their bones and the table itself. This is the scatter we worry about.

So let’s assume that the closest person to the patient is 3 feet away. Remember that radiation intensity diminishes as the square of the distance. So if the distance doubles, the intensity decreases to one fourth. By calculating the intensity of the small amount of scatter at 3 feet from the patient, we come up with a whopping 0.2 microGrays. Since most people are even further away, the dose is much, much less for them.

Let’s put it perspective now. The background radiation we are exposed to every day (from cosmic rays, brick buildings, etc) amounts to about 2400 microGrays per year. So 0.2 microGrays from chest xray scatter is less than the radiation we are exposed to naturally every hour!

The bottom line: unless you need to work out you shoulders and pecs, don’t bother to lift your lead apron every time the portable xray unit beeps. It’s a waste of time and effort!

How To: Flexion / Extension Views of the Cervical Spine

Clearance of the cervical spine can often be done using clinical criteria alone (see this video at http://youtu.be/NhjF9kDOcjE). If this is not possible, a combination of radiologic and clinical evaluation is usually carried out. 

In some cases, radiographic studies (usually CT) are normal, but there is pain on clinical exam. Our next step is to send the patient to xray for flexion and extension views. This exam is performed by removing the collar while the patient is sitting, so the thoracic and lumbar spines must be clear before ordering this. The patient then gently flexes and extends the neck to their limits of comfort. Images are then obtained at the limits of flexion and extension. The premise is that a normal, awake patient cannot and will not move their neck beyond their comfort level to the point where they could cause themselves neurologic injury. 

It is very important that you look at the images yourself. The radiologist may review the images and will report that “there is no evidence of subluxation at the limits of flexion and extension.” But the patient may have barely moved their neck!

The question is: how much flexion and extension do you need to have to clear the spine?

The answer is not easy to find, and is buried in literature from the 1980s and 90s. According to the EAST guidelines, the ideal amount is 30 degrees from neutral for both flexion and extension. This is not always achievable in elderly patients, so in those cases you must use your judgment. Talk to the patient to find out if they stopped moving their neck forward or backward due to pain, or because they just can’t move it that far.

Trouble signs to look for are:

  • Subluxation of more that 2mm at any level
  • Angulation of more than 11 degrees

Any abnormality should prompt a spine consult.

If the study is not abnormal but the amount of flexion and/or extension is not adequate, there are two options. First, just leave the collar in place and try again in a week or so and try again. This will allow any soft tissue injuries to get better and may allow a successful repeat study. The alternative is a more costly and less well-tolerated MRI.

References:

  1. EAST Practice Guidelines, Identifying Cervical Spine Injuries Following Trauma – Update (2000).
  2. Defining radiographic criteria for flexion-extension studies of the cervical spine. Robert Knopp et al. Ann Emerg Med. 2001 Jul;38(1):31-5.