Tag Archives: TTA

Is The Trauma Bay Chest X-Ray Really Necessary Or Just Dogma?

I love challenging dogma. I spoke last week (virtually) at an excellent event at the Intermountain Medical Center in Utah. One of my talks there addressed trauma myths and dogma.

I bring this up because there is an interesting article in the Journal of Trauma this month that questions the necessity of the routine chest x-ray (CXR) in blunt trauma resuscitation. So of course, this caught my eye. Let’s dig in.

The first thing to understand is that this article is an opinion piece and is identified as such. It was written by three surgeons, including the trauma medical director, at the Stanford University Hospital trauma center.

First, what are we really looking for on the chest x-ray that is taken in the trauma bay? I call them “the three big things”.

  • Big air. The first item to be identified is a pneumothorax. The chest x-ray helps the trauma professionals decide if the pneumo needs an intervention (chest tube) and when. (Note: it could in theory identify a tension pneumothorax. But in that case, the trauma pros should be embarrassed. They should have picked that up on their clinical exam and assessment of the vitals.)
  • Big blood. The chest x-ray can also identify a hemothorax. And once again, it can help decide whether its size warrants chest tube insertion.
  • Big mediastinum. A wide mediastinum may indicate the presence of hematoma from an aortic injury. It is one of the indications for performing CT angiography of the chest to rule it out.

Here are their authors’ arguments:

  • There are other imaging modalities available to us that are very accurate. FAST ultrasound has been used routinely for abdominal and cardiac evaluation for over a decade. The extended FAST (eFAST) involves evaluation of the pleural interface to identify pneumothorax. A study published last year pitted CXR vs eFAST. It found that the eFAST outperformed with a sensitivity of 94% and specificity of nearly 100%.
    But what about hemothorax? Ultrasound is less helpful here. But the CT scanner is. It is far more accurate at identifying and quantifying hemothorax than the CXR.
  • Evaluation of the aorta can either wait, or it can’t wait at all. If the patient loses vital signs in the trauma bay the decision to open the chest or insert a REBOA catheter must be made. In the latter case, a chest x-ray must be obtained to exclude a thoracic source of bleeding that the cathether is of no use for. But if the patient truly is bleeding out from a blunt aortic injury, it is nearly certain that he or she is not leaving the trauma bay alive.
    What about using the wide mediastinum as an indication or order the chest CT angiogram? The authors argue that there will probably be a history of deceleration or other associated injuries (femur fracture is a very common one).

Bottom line: The authors argue that the chest x-ray should go the way of the lateral cervical spine x-ray used at the turn of the 21st century and before. They claim that judicious use of the extended FAST and CT angiography can identify the significant injuries we need to know about in a timely manner.

My own opinion is more nuanced. I buy their arguments that the extended FAST will identify all significant pneumothoraces. However, we have typically answered the question “how big is too big” using the chest x-ray. That is the most helpful tool in deciding whether a chest tube is warranted or not.

As for hemothorax, I don’t believe that a CT is the best tool for evaluating this, either. Are the authors members of the “pan-scan” school? What about those of us that use the “selective scan” philosophy. True, the abdominal scan will identify both hemothorax and pneumthorax on the lower cuts of the chest. But as in the previous paragraph, we are better trained to judge when a chest tube is indicated by the appearance of the chest x-ray. Hemothorax (or pneumothorax) is not an indication to get a chest CT.

I don’t buy argument that there will be other indications of potential aortic injury. Deceleration is in the eye of the beholder. How do we know how fast the vehicle was actually moving? What is the magic velocity that will break this patient’s aorta? This particular patient may not have any of the other potential indicators that increase suspicion for aortic injury. That wide mediastinum may be the only clue. Yes, the numbers of affected patients are small, but the consequences of missing one could be deadly.

And what about patients who might not get scanned at all? And those who need a study to confirm tube or line placement? They must absolutely get a chest x-ray before they leave the trauma bay.

At this point, I can’t see a way to dispense with the chest x-ray completely. It should still be used to:

  • Confirm pneumothorax from eFAST to help decide if a chest tube is needed
  • Identify potential pathology (hemothorax, wide mediastinum) in patients who don’t otherwise meet criteria for chest CT
  • Verify endotracheal tube position after intubation

What do you think? Please leave your comments or Tweets about this topic.

References:

  • Extended-FAST plus MDCT in pneumothorax diagnosis of major trauma: time to revisit ATLS imaging approach? J Ultrasound. 2019;22(4):461–469.
  • Necessity of routine chest radiograph in blunt trauma resuscitation: Time to evaluate dogma with evidence. J Trauma 2020;89(3):e69-70.

ACS Trauma Abstracts #3: Using Mechanism Criteria To Activate The Trauma Team

Most US trauma centers have two tiers of trauma activation. The higher tier is typically called for physiologic derangements like hypotension, tachypnea, or decreased mental status. This triggers arrival of the full trauma team for rapid assessment and management.

The second tier is reserved for patients who may be less seriously injured and usually results in a reduced team. And depending on how good the activation criteria for this tier are, many patients eventually turn out to have no serious injuries and are discharged from the emergency department. This is the purest form of overtriage, and if it occurs frequently, can wear down your trauma team and waste resources.

Criteria for the second tier trauma activation may include mechanism of injury criteria such as ejection, pedestrian struck, intrusion into the passenger compartment, death at the scene, and other similar criteria. They sound like good criteria, but how helpful are they, really? The group at Baylor University Medical Center in Dallas performed a retrospective review of their trauma activations over a one and a half year period to test the efficacy of some of these criteria. They had recently added some mechanism-based criteria to their second tier activations.

Here are the factoids:

  • During the study period, they had 1325 second tier activations, and 603 were based on mechanism criteria
  • The mean injury severity score of mechanism-based criteria was only 5, versus 10 for anatomic criteria (significant)
  • A whopping 37% of mechanistic criteria patients were discharged home from the ED, versus only 10% for other criteria (also significant)
  • Second tier activations for physician discretion were just as good as non-mechanism criteria, with an ISS of 10 and 13% discharged home
  • Looking at specific criteria, compartment intrusion, ejection, and death in the compartment appeared to be the major overtriage offenders, with an ISS of 5 and 40% discharge rate
  • Incidentally, penetrating injury proximal to knee or elbow had very high overtriage rates, with an ISS of 1 and discharge rate of 48%

Bottom line: Trauma centers are encouraged to review their trauma triage criteria periodically, especially when overtriage rates are high. This center is presenting a nice paper that shows the benefit of doing this. They identified four mechanistic criteria that do not appear to be any better than just relying on physician discretion. What they are not saying is that it is probably better to rely on physiologic and anatomic criteria, as well as physician discretion, to determine which level of trauma activation to trigger.

And incidentally, the new ACS highest-level criterion of gunshot proximal to knee or elbow may not be everything its cracked up to be. It’s difficult to say for sure because stabs and gunshots were not separated out in this abstract, and the number they encountered was not specified. But it certainly suggests this criterion needs some fine-tuning as well.

Reference: Intrusion, ejection, and death in the compartment: mechanism-based trauma activation criteria fail to identify seriously injured patients. JACS 225(4S1):S56, 2017.

When Is It Too Late To Call A Trauma Activation?

This is a related, follow-on post from yesterday, where I discussed activating your trauma team after transfer from another hospital. What about patients presenting directly to your hospital, but some time after their injury?

Admit it. It’s happened to you. You get paged to a trauma activation, hustle on down to the ED, and get dressed. The patient is calmly and comfortably lying on a cart, staring at you like you’re from Mars. Then you hear the story. He has a grade V spleen injury. But he just got back from CT scan. And his car crash was yesterday!

Is this appropriate? The answer is no! But, as you will see, the answer is not always as obvious as this example. The top thing to keep in mind in triggering a trauma activation appropriately is the reason behind having them in the first place.

The entire purpose of a trauma activation is speed. The assumption must be that your patient is dying and you have to (quickly) prove that they are not. It’s the null hypothesis of trauma.

Trauma teams are designed with certain common features:

  • A group of people with a common purpose
  • The ability to speed through the exam and bedside procedures via division of labor
  • Rapid access to diagnostic studies, like CT scan
  • Availability of blood products, if needed
  • Immediate access to an OR, if needed
  • Recognition in key departments throughout the hospital that a patient may need resources quickly

Every trauma center has trauma activation triage criteria that try to predict which patients will need this kind of speed. Does the patient in the example above need this? NO! He’s already been selected out to do well. Why, he’s practically finished the nonoperative solid organ management protocol on his own at home.

Here are some general rules:

  • If the patient meets any of your physiologic and/or anatomic criteria, they are or can be sick. Trigger immediately, regardless of how much time has passed.
  • If they meet only mechanism criteria and it’s been more than 6 hours since the event, they probably do not need the fast track.
  • If they only meet the “clinician / EMS judgment” criteria, think about what the suspected injuries are based on a quick history and brief exam. Once again, if more than 6 hours have passed and there are no physiologic disturbances, the time for needing a trauma activation is probably past.

If you do decide not to trigger an activation in one of these cases, please let your trauma administrative team (trauma medical director, trauma program manager) know as soon as possible. This may appear to be undertriage as they analyze the admission, and it’s important for them to know the reasoning behind your choice so they can accurately document under- and over-triage.

Related posts:

When Is It Too Late To Call A Trauma Activation?

Admit it. It’s happened to you. You get paged to a trauma activation, hustle on down to the ED, and get dressed. The patient is calmly and comfortably lying on a cart, staring at you like you’re from Mars. Then you hear the story. He has a grade V spleen injury. But he just got back from CT scan. And his car crash was yesterday

Is this appropriate? The answer is no! But, as you will see, the answer is not always as obvious as this example. The top thing to keep in mind in triggering a trauma activation appropriately is the reason behind having them in the first place.

The entire purpose of a trauma activation is speed. The assumption must be that your patient is dying and you have to (quickly) prove that they are not. It’s the null hypothesis of trauma.

Trauma teams are designed with certain common features:

  • A group of people with a common purpose
  • The ability to speed through the exam and bedside procedures via division of labor
  • Rapid access to diagnostic studies, like CT scan
  • Availability of blood products, if needed
  • Immediate access to an OR, if needed
  • Recognition in key departments throughout the hospital that a patient may need resources quickly

Every trauma center has trauma activation triage criteria that try to predict which patients will need this kind of speed. Does the patient in the example above need this? NO! He’s already been selected out to do well. Why, he’s practically finished the nonoperative solid organ management protocol on his own at home.

Here are some general rules:

  • If the patient meets any of your physiologic and/or anatomic criteria, they are or can be sick. Trigger immediately, regardless of how much time has passed.
  • If they meet only mechanism criteria and it’s been more than 6 hours since the event, they probably do not need the fast track.
  • If they only meet the “clinician / EMS judgment” criteria, think about what the suspected injuries are based on a quick history and brief exam. Once again, if more than 6 hours have passed and there are no physiologic disturbances, the time for needing a trauma activation is probably past.

If you do decide not to trigger an activation in one of these cases, please let your trauma administrative team (trauma medical director, trauma program manager) know as soon as possible. This may appear to be undertriage as they analyze the admission, and it’s important for them to know the reasoning behind your choice so they can accurately document under- and over-triage.

Related posts: