Category Archives: Thorax

How Common Is BCVI, Really?

August 27, 2021 The Trauma Pro Leave a comment

Blunt carotid and vertebral artery injuries (BCVI) are an under-appreciated problem after blunt trauma. Several screening tools have been published over the years, but they tend to be unevenly applied at individual trauma centers. I will discuss them in detail in the next section.

For the longest time, the overall incidence of BCVI was thought to be low, on the order of 1-2%. This is the number I learned years ago, and it has not really changed over time.

But how do we know for sure? Well, the group at Birmingham retrospectively reviewed every CT angiogram (CTA) of the neck they did in a recent two-year period. They did this after adopting a policy of imaging each and every one of their major blunt trauma patients for BCVI. Each patient chart was also evaluated to see if the patient met any of the criteria for the three commonly used screening systems.

During the study period, a total of 6,287 of 6,800 blunt trauma patients underwent BCVI screening with CTA of the neck. They discovered that 480 patients (7.6%) were positive for BCVI!

This is a shocking 8x higher than we expected! Why hasn’t this been obvious until now? Most likely because we were previously only aware of patients who became symptomatic. Luckily, many of these patients dodge the proverbial bullet and never exhibit any symptoms at all.

So why should we be worried? This is one of those clinical entities like blunt thoracic aortic disruption that potentially has terrible consequences if ignored. Although the number of patients who develop sequelae from their BCVI is small, suffering a stroke can be catastrophic.

Should we perform a screening study for all blunt trauma patients? Seems like overkill, or is it? Is there any way we be more selective about it?

In the next post, I’ll review the three current screening tools used to determine which patients should receive CTA, and how good they are.

Reference: Universal screening for blunt cerebrovascular injury. J Trauma 90(2):224-231, 2021.

Head, Thorax

It’s BCVI Week!

August 25, 2021 The Trauma Pro Leave a comment

This post will kick off a series of posts on BCVI. What is that, you ask? There seems to be some confusion as to what the acronym BCVI actually stands for. Some people believe that it means blunt cerebrovascular injury. This is not correct, because that term refers to injury to just about any vessel inside the skull.

The correct interpretation is blunt carotid and vertebral artery injury. This term refers to any portion and any combination of injury to those two pairs of vessels, from where they arise on the great vessels, all the way up into the base of the skull. Here’s a nice diagram:

Note that we will be excluding the external carotid arteries from this discussion, since injuries to them do not have any impact on the brain. They can cause troublesome bleeding, though.

These arteries are relatively protected from harm during blunt trauma. But given enough energy, bad things can happen. Fortunately, injuries to these structures are not very common, but unfortunately many trauma professionals under-appreciate their frequency and severity.

Over the next four posts, I’m going to provide an update on what we know about BCVI. I will try to tease out the true incidence, review the (multiple) screening systems, and discuss various ways to manage these injuries.

In the next post, we’ll explore the incidence of this injury. Is it truly as uncommon as we think?

Thorax

Delayed Hemothorax In Older Adults: Real Or Not?

April 6, 2021 The Trauma Pro Leave a comment

I came across an interesting paper in the Journal of Trauma & Acute Care Surgery Open recently. I always read these articles a bit more critically, though, because the peer review process just doesn’t feel quite the same to me as the more traditional journal process. But maybe it’s just me.

In this paper, the authors decided to look at the incidence of delayed hemothorax because “emerging evidence suggests HTX in older adults with rib fractures may experience subtle hemothoraces that progress in a delayed fashion over several days.” They cite two references to back up this rationale.

They retrospectively reviewed records from two busy US Level I trauma centers for adults age 50 or older who were diagnosed with delayed hemothorax (dHTX). Delayed was defined as 48 hours or more after initial chest CT showed either a minimal or trace HTX. The authors went on to analyze the characteristics and demographics of the patients involved.

Here are the factoids:

A total of 14 older adults experienced dHTX after rib fractures, an overall incidence of 1.3% (!)
About half were diagnosed during the initial hospitalization for the fractures
All patients had multiple fractures, with an average of 6 consecutive ones; four had a flail chest
One third progressed from a trace HTX, two thirds had a completely negative initial chest CT
Only one third were taking anticoagulants or anti-platelet agents
Patients with multiple fractures, posteriorly located, and displaced were most likely to develop dHTX

The authors concluded that “delayed progression and delayed development of HTX among older adults with rib fractures require wider recognition.”

Bottom line: Really? First, I looked at the papers cited by the authors as the rationale for doing this study. They each found dHTX in about 10% of patients, but their definition was very broad: any fluid visible on upright chest x-ray. Furthermore, the patients were not really “older” either. Average age was around 50.

So I’m not sure yet whether this is a problem, especially with the low incidence of 1.3%. This study doesn’t come right out and state how many patients they reviewed to find their 14, but it can be calculated to be 14 / 1.3% = 1,177. This incidence is only one tenth of that found in the two studies cited. Seems relatively uncommon, and half were discovered while the patients were still in the hospital. Thus only 0.65% sought readmission for chest discomfort or difficulty breathing.

This study required chest CT for rib fracture diagnosis. Is all that radiation (and possibly contrast) really necessary? And did these patients get another chest CT to delineate the pathology? More radiation?

Overall, this paper was not very helpful to me. Yes, I have seen patients come back days or weeks later with a hemothorax that was not seen during their first visit. It’s just that this study raises many more questions that should have been easily answered in the discussion. But they weren’t.

Given that only about a half of a percent of rib fracture patients develop delayed hemothorax after discharge, it is probably prudent to provide information to the patient recommending they see their practitioner if they develop any symptoms days or weeks later. And a simple chest x-ray should do.

Reference: Complication to consider: delayed traumatic hemothorax in older adults. Trauma Surgery & Acute Care Open 2021;6:e000626. doi: 10.1136/tsaco-2020-000626.

Thorax

Detecting Rib Fractures In The Elderly

March 25, 2021 The Trauma Pro Leave a comment

It’s well known that our elders do less well than younger folks after injury. The number of complications is higher, there tends to be more loss of independence during recovery, and mortality is increased. This is not only true of high energy trauma like car crashes, but also much lower energy events such as a fall from standing.

Rib fractures are common after falls in the elderly and contribute to significant morbidity if not treated adequately. Traditionally, they are identified through a combination of physical exam and chest x-ray. Unfortunately, only half of rib fractures are visible on x-ray. It falls to the physical exam to detect the rest.

A group at Beth Israel Hospital in Boston explored the utility of using chest CT in an attempt to determine if this would result in more appropriate and cost-efficient care in the elderly. They performed a retrospective study of 3 years of their own data on patients aged 65 or more presenting after a mechanical fall and receiving a rib fracture diagnosis. Imaging was ordered at the discretion of the physician. A total of 330 patients were elderly, fell, and had both chest x-ray and chest CT obtained. This was a very elderly group, with a mean age of 84 years!

Here are the factoids:

Rib fractures were seen on chest x-ray in 40 patients (12%) and on CT in an additional 56 ; 234 patients had no fractures on either
When fractures were seen on both studies, CT identified a median of 2 more fractures than chest x-ray
Patients with fractures not seen on chest x-ray were admitted significantly more often than those without fractures (91% vs 78%)
Mortality, admission to ICU, ICU length of stay, and hospital length of stay were not different if fractures were seen only on CT
CT scan identified new issues or clarified diagnoses suggested by chest x-ray in 14 cases, including one malignancy
Rib detail images were obtained in 13 patients and proved to be better than chest x-ray, but not quite as good as CT scan

Conclusion: use of CT for rib fracture diagnosis resulted in a few more admissions, but no change in hospital resource utilization, complications, or mortality.

Bottom line: Hmm…, read the paper closely. The authors conclude that more patients with CT-only identified rib fractures are admitted. But compared to what? Unfortunately, patients without rib fractures on CT. What about comparing to patients who had fractures seen on chest x-ray too? If that number is the same, then of what additional use is CT? Identifying a few incidentalomas?

Given that there is no change in the usual outcome measures listed here, it doesn’t seem like there is any additional benefit to adding CT. And I can see a lot of downsides: cost, radiation, and possible exposure to IV contrast. In my mind, there is still nothing that beats a good physical exam and a chest x-ray. Skip the CT scan. And don’t even think about ordering rib detail images! That’s so 1990s. And even if no rib fractures are seen on imaging, physical exam is the prime determinant for admitting your patient for aggressive pain management and pulmonary toilet.

Reference: Chest CT imaging utility for radiographically occult rib fractures in elderly fall-injured patients. J Trauma 86(5):838-843, 2019.

Thorax

Delayed Presentation Of Right Diaphragm Injury

November 24, 2020 The Trauma Pro Leave a comment

Diaphragm injury from blunt trauma is uncommon, occurring in only a few percent of patients after high energy mechanisms. They usually occur on the left side, and are more frequently seen after t-bone type car crashes and in pedestrians struck by a car.

Blunt diaphragm injury on the right side is very unusual. Even so, it is more easily detected due to obvious displacement of the liver that can be seen on chest x-ray. Blunt injuries on the right side usually result in a large rent in the central tendon, or detachment of the diaphragm from the chest wall. This allows the liver to herniate into the chest, and the chest x-ray finding is not subtle.

This image shows an acute herniation of the liver through the diaphragm. Due to the size of the liver, only part of it can typically fit through the rent. Radiologists call this the “cottage loaf” sign. Why? Here’s the bakery item it is named after. Get it now?

Thankfully, most of these injuries are identified in the acute setting. They must be addressed surgically because, if left untreated, more and more of the liver will slowly move into the chest resulting in respiratory problems in the long run.

Acute management usually consists of laparotomy to address both the diaphragm tear and any other associated intra-abdominal injuries. The liver should be reduced by sliding a hand next to it laterally into the chest cavity and pushing the dome downwards. The right triangular ligaments should be taken down (if they are not already destroyed) to mobilize the organ better so the diaphragm laceration can be closed. This is typically accomplished with some type of large (size 0) permanent suture. A chest tube will be needed to evacuate the iatrogenic pneumothorax created by opening the abdomen.

Chronic right diaphragm injuries are a different animal entirely. There is no longer any need to evaluate for intra-abdominal injury, so the procedure is usually performed through the chest. For smaller injuries, thoracoscopic procedures have been described that push the liver downwards and then either suture the diaphragm primarily or (more likely) incorporate a piece of mesh.

Larger injury requires conversion to an open procedure so more muscle power can be used to push the liver downwards to facilitate the repair. However, do not underestimate the adhesions that will be present between diaphragm and liver (and possibly the lung) in long-standing injuries. It may take some time to dissect them away. Rarely, a laparotomy (or laparoscopy) may be needed to assist for very large and complex injuries.

References:

Management of Delayed Presentation of a Right-Side Traumatic
Diaphragmatic Rupture. World J Surg 36:260-265, 2012.
Delayed Discovery of Diaphragmatic Injury After Blunt Trauma:
Report of Three Cases. Surg Today 35:407-410, 2005.

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