All posts by TheTraumaPro

CT Cystography For Bladder Trauma

Bladder injury after blunt trauma is relatively uncommon, but needs to be identified promptly. Nearly every patient (97%+) with a bladder injury will have hematuria that is visible to the naked eye. This should prompt the trauma professional to obtain a CT of the abdomen/pelvis and a CT cystogram.

The CT of the abdomen and pelvis will identify any renal or ureteral (extremely rare!) source for the hematuria. The CT cystogram will demonstrate a bladder injury, but only if done properly!

During most trauma CT scanning of the abdomen and pelvis, the bladder is allowed to passively fill, either by having no urinary catheter and having the patient hold it, or by clamping the catheter if it is present. Unfortunately, this does not provide enough pressure to demonstrate small intraperitoneal bladder injuries and most extraperitoneal injuries.

The proper technique involves infusing contrast into the bladder through a urinary catheter. At least 350cc of dilute contrast solution must be instilled for proper distension and accurate diagnosis. This can be done prior to the abdominal scan. Once the initial scan has been obtained, the bladder must be emptied and a focused scan of just the bladder should be performed (post-void images). Several papers have shown that this technique is as accurate as conventional retrograde cystography, with 100% sensitivity and specificity for intraperitoneal ruptures. The sensitivity for extraperitoneal injury was slightly less at 93%.

Bottom line: Gross hematuria equals CT of the abdomen/pelvis and a proper CT cystogram, as described above. Don’t try to cheat and passively fill the bladder. You will miss about half of these injuries!

Related posts:

Reference: CT cystography with multiplanar reformation for suspected bladder rupture: experience in 234 cases. Am J Roentgenol 187(5):1296-302, 2006.

Intraperitoneal bladder rupture

Extraperitoneal bladder injury

Crowdfunding: The Future Of Research Funding?

Many readers are familiar with the concept of “crowdsourcing”, or tapping into a pool of people connected via the internet to obtain something of value. This something might be information, services (think Uber), or content (99designs). And with the advent of websites like KickStarter, it is now possible to crowdsource money.

As anyone who has an academic focus can attest, there is tremendous pressure to pursue (hopefully) meaningful research. In many cases, this is an integral part of keeping one’s job. But research is expensive. Even the simplest retrospective study requires some kind of statistical analysis, and statisticians don’t work for free. And in more sophisticated research labs, there are huge personnel, equipment, as well as other infrastructure costs. 

Traditionally, researchers have pursued grant dollars from single sources like the federal government, local agencies, corporations, and charitable organizations. But this is very competitive, and it’s usually an all or none proposition. Only one of many applications gets all the cash, and the rest get none.

But now, crowdsourcing has moved beyond the technology and design type projects seen on KickStarter to what is now called crowdfunding. There are a number of sites that solicit small donations from individuals, pooling them together into large amounts. The largest campaign on KickStarter was able to amass over $20 million to create a new version of the Pebble watch. A small campaign to get $10 to develop a potato salad recipe ended up collecting over $55 thousand.

Bottom line: The concept of crowdfunding has now made the jump to funding research. There are a number of sites that are structured similarly to KickStarter that allow researchers to solicit donations from the public. Some are relatively rudimentary, and some are naive in their approach to soliciting funds. In order to engage the public to contribute sums of money, large or small, research teams will need to explain their ideas simply and describe some practical or potential application. And it won’t hurt to offer some type of schwag for donors at various financial levels.

A few interesting crowdfunding sites:

March Trauma MedEd Newsletter Released

The Marchnewsletter is now available! Click the image below or the link at the bottom to download. This month’s topic is “The Elderly”.

In this issue you’ll find articles on:

  • How we take care of our elders
  • Thoughts on geriatric trauma
  • Elderly trauma and the frailty index
  • The medical orthopedic service
  • Consequences of elderly falls
  • Effects of an in-hospital falls prevention program

Subscribers received the newsletter last week. If you want to subscribe to get early delivery in the future (and download back issues), click here.

Click here to download and/or subscribe.

Penetrating Injuries to the Extremities

Simple penetrating injuries to the arms and legs are often over-treated with invasive testing and admission for observation. Frequently, these injuries can be rapidly evaluated and disposed of using physical examination skills alone.

Stabs and low velocity gunshots (no rifles or shotguns, please) should be thoroughly examined. This includes an examination of the entire, unclothed body. If this is not carried out, there is a risk that additional penetrating injuries may be missed.

For gunshots, look at the wounds and the estimated trajectory to try to demonstrate that the object stayed clear of neurovascular structures. This exam is imprecise, and must be accompanied by a full neurovascular exam and evaluation of the bones and joints. If there is any doubt regarding bony involvement, plain radiographs with entry markers should be performed. Any abnormal findings will require more in-depth evaluation and inpatient admission.

If the exam is negative but the trajectory is “in proximity” to a major vessel, an arterial pressure index (API) should be measured. This test involves the calculation of the ratio of the systolic pressure in the injured extremity to the contralateral uninjured extremity. It should not be confused with the ankle brachial index (ABI) which compares the systolic pressure in the ipsilateral uninjured arm  or leg.

The magic ratio is 0.9. If the API is less than this, there is some likelihood that a vascular injury is present. If the API is higher, there is virtually no chance of injury.

The final test that must be performed before discharge is a function test. If the injured extremity is too painful to use or walk on, the patient may need to be admitted for pain management and therapy. Patients managed in this way can avoid arteriography, CT angiography or admission and save thousands of dollars in hospital charges.

Reference: Journal Am Coll Surgeons 2009;209:740-5.

A Better Concussion Test?

Concussions from sports activities are all over the news these days. This injury is particularly important when dealing with the developing brains of student athletes. Most organized sporting activities take advantage of existing concussion testing on the sidelines, such as the Standardized Assessment of Concussion test (SAC, a cognitive test), and the tandem gait test (balance). 

However, sports concussions frequently involve the visual pathways as well. In an effort to improve concussion recognition, a New York group studied the addition of a visual test (King-Devick test, K-D) to their concussion battery. A large group of youth and collegiate hockey and lacrosse players were evaluated at their baseline with K-D, SAC, and tandem gait. During games, athletes with potential concussions were tested on the sidelines. They were compared to non-concussed athletes who were also tested on the sidelines.

Here are the factoids:

  • 243 student athletes were studied, average age 11
  • 12 athletes sustained concussions, and their performance on the K-D test worsened significantly
  • The K-D test identified concussions better than the cognitive and balance tests

Bottom line: The addition of the King-Devick test appears to improve concussion identification in young athletes. In fact, it may be possible to use just this test alone. But practically speaking, it is probably better to use as part of a battery of tests to identify possible concussion after a significant impact. This enables coaches to minimize the number of players that might sustain additional injury and develop the risk for later sequelae of concussion. 

Related posts:

Reference: Adding vision to concussion testing: a prospective study of sideline testing in youth and collegiate athletes. J Neuro-opthalmology 2015 Feb 18, epub ahead of print.