Category Archives: General

Why We Can’t Just Stop Anticoagulants In Trauma Patients

We’ve all been faced with injured patients who are taking some kind of anticoagulant, and it complicates their care. Why can’t we just stop them in patients at risk for injury (e.g. an elderly patient who falls frequently)?

Two major risk groups come to mind: those taking the meds who have DVT (or a propensity to get it), and patients with atrial fibrillation who take them to decrease stroke risk. I was not able to find much info (yet) on the former category. But there is a series of nicely done studies based on work from the Framingham Heart Study.

The Framingham study started in 1948, and has been following over 5,000 people for the development of cardiovascular disease. In this particular analysis, 5070 patients who were initially free of disease were analyzed for development of atrial fib and occurrence of stroke. Anticoagulants were seldom used in this group.

The authors found that the prevalence of stroke increased with age in patients with atrial fib. The percentage that could be attributed to a-fib also increased. The following summarizes their numbers:

  • Age 50-59: 0.5 strokes per 100 patients, attributable risk 1.5%
  • Age 60-69: 1.8 strokes per 100 patients, attributable risk 2.8%
  • Age 70-79: 4.8 strokes per 100 patients, attributable risk 9.9%
  • Age 80-89: 8.8 strokes per 100 patients, attributable risk 23.5%

Bottom line: The risk of having a stroke just because a patient has atrial fibrillation goes up significantly with age. So setting an age cutoff for taking an anticoagulant doesn’t make sense. Unfortunately, increasing age also means increasing risk of injury from falls. Warfarin definitely cuts that risk, and it happens to be relatively easily reversbile. However, the newer non-reversible drugs change the equation, shifting the risk/benefit ratio too far toward the dark side. We need some good analyses to see if it really makes sense to move everybody to these new (expensive) drugs just to make it easier to dose and monitor. The existing studies on them only look at stroke, but don’t take injury morbidity and mortality into account.

Reference: Atrial fibrillation as an independent risk factor for stroke: the Framingham study. Stroke 22:983-988, 1991.

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Novel Hip Reduction Technique: The Captain Morgan

I wrote about posterior hip dislocation and how to reduce it using the “standard” technique quite some time ago (see link below). Emergency physicians and orthopedic surgeons at UCSF-Fresno have published their experience with a reduction technique called the Captain Morgan.

Named after the pose of the trademark pirate for Captain Morgan rum, this technique simplifies the task of pulling the hip back into position. One of the disadvantages of the standard technique is that it takes a fair amount of strength (and patient sedation) to reduce the hip. If the physician is small or the patient is big, the technique may fail.

In the Captain Morgan technique, the patient is left in their usual supine position and the pelvis is fixed to the table using a strap (call your OR to find one). The dislocated hip and the knee are both flexed to 90 degrees. The physician places their foot on the table with their knee behind the patient’s knee. Gentle downward force is placed on the patient’s ankle to keep the knee in flexion, and the physician then pushes down with their own foot, raising their calf. Gentle rotation of the patient’s hip while applying this upward traction behind the patient’s knee usually results in reduction.

Some orthopedic surgeons use a similar technique, but apply downward force on the patient’s ankle, using the leverage across their own knee to develop the reduction force needed. The Captain Morgan technique use the upward lift from their own leg to develop the reduction force. This may be gentler on the patient’s knee.

The authors report a series of 13 reductions, and all but one were successful. The failure occurred due to an intra-articular fragment, and that hip had to be reduced in the operating room.

I’m interested in hearing comments from anyone who has used this technique (or the leverage one). And does anyone have any other techniques that have worked for them?

Related post:

Reference: The Captain Morgan technique for the reduction of the dislocated hip. Ann Emerg Med (in press) dol:1016/j.annemergmed.2011.07.010, 2011.

Liver Laceration And Liver Function Tests

Over the years I’ve seen a number of trauma professionals, both surgeons and emergency physicians, order liver transaminases (SGOT, SGPT) and bilirubin in patients with liver laceration. I’ve never been clear on why, so I decided to check it out. As it turns out, this is another one of those “old habits die hard” phenomena.

Liver lacerations, by definition, are disruptions of the liver parenchyma. Liver tissue and bile ducts of various size are both injured. Is it reasonable to expect that liver function tests would be elevated? A review of the literature follows the typical pattern. Old studies with very few patients.

From personal hands-on observations, the liver tissue itself tears easily, but the ducts are a lot tougher. It is fairly common to see small, intact ducts bridging small tears in the substance of the liver. However, larger injuries can certainly disrupt major ducts, leading to major problems. But I’ve never seen obstructive problems develop from this injury.

A number of papers (very small, retrospective series) have shown that transaminases can rise with liver laceration. However, they do not rise reliably enough to be a good predictor of either having an injury, or the degree of injury. Similarly, bilirubin can be elevated, but usually not as a direct result of the injury. The most common causes are breakdown of transfused or extravasated blood, or from critical care issues like sepsis, infection, and shock.

Bottom line: Don’t bother to get liver function tests in patients with known or suspected injury. Only a CT scan can help you find and/or grade the injury. And never blame an elevated bilirubin on the injury. Start searching for other causes, because they will end up being much more clinically significant.

References:

  • Evaluation of liver function tests in screening for intra-abdominal injuries. Ann Emerg Med 20(8):838-841, 1991.
  • Markers for occult liver injury in cases of physical abuse in children. Pediatrics 89(2):274-278.
  • Combination of white blood cell count with liver enzymes in the diagnosis of blunt liver laceration. Am J Emerg Med 28(9):1024-1029, 2010.

Do You Really Need To Repeat That Trauma Bay Xray?

It happens all the time. You get that initial chest and/or pelvic xray in the resuscitation room while evaluating a blunt trauma patient. A few minutes later the tech returns with another armful of xray plates to repeat them. Why? The patient was not centered properly and part of the image is clipped.

Where is the left side of the chest, and do we care?

Do you really need to go through the process of setting up again, moving the xray unit in, watching people run out of the room (if they are not wearing lead, and see my post below about how much radiation they are really exposed to), and shooting another image? The answer to the question lies in what you are looking for. Let’s address the two most common (and really the only necessary) images needed during early resuscitation of blunt trauma.

First, the chest xray. You are really looking for 3 things:

  • Big air (pneumothorax)
  • Big blood (hemothorax)
  • Big mediastinum (hinting at aortic injury)

Look at the clipped xray above. A portion of the left chest wall is off the image. If there were a large pneumothorax on the left, would you be able to see it? What about a large hemothorax? And the mediastinum is fully included, so no problem there. So in this case, no need to repeat immediately.

The same thing goes for the pelvis. You are looking for gross disruption of the pelvic ring, especially posteriorly because this will cause you to intervene in the ED (order blood, consider wrapping the pelvis). So if parts of the edges or top and bottom are clipped, no big deal.

Bottom line: Don’t let the xray tech disrupt the team again by reflexively repeating images that are not technically perfect. See if you can use what you already have.  And how do you decide if you need to repeat it later, if at all? Consider the mechanism of injury and the physical exam. Then ask yourself if there is anything you could possibly see that was not imaged the first time that would change your management in any way. If not, you don’t need it. But it certainly will irritate the radiologists!

The Impact Of Radiographic Image Sharing Systems On Trauma Transfers

There has been a big push to implement systems of trauma centers across the US, primarily at the state level. This move to get the right patient to the right hospital has resulted in an increased number of transfers, and rightly so. However, the referring hospital frequently performs some radiographic imaging before transfer.

So it is critical that both the patient and their imaging get to the receiving hospital for good continuity of care. Failure to do so results in re-imaging, additional exposure to radiation, delays in care, and potentially increased costs. Radiologists may be reluctant to read outside images because they generally will not get paid for it.

Unfortunately, there are lots of barriers to getting those images to the receiving trauma center. They may forget to send a disc. The disc may not work on the receiving hospital’s computers. A direct connection between PACS systems may be lacking, or may not work. In any case, patient care may suffer.

Cloud solutions using web-based software and an intermediary for image storage and delivery have been around for years. Their use is inconsistent around the US, mainly because they cost money. A group in Ohio looked at the impact of implementing one of these system on the incidence of cost of re-imaging at their Level I trauma center. Four years of patient transfer data were reviewed for imaging at the first hospital, re-imaging at the trauma center, and charges. The authors compared re-imaging rates before and after the availability of the cloud sharing system.

Here are the factoids:

  • 1,081 transfers occurred during the study period, and 639 (59%) had at least one CT prior to transfer
  • 345 repeat scans were performed on 222 patients (35%)
  • The most common repeats were head CT (32%) and cervical spine (23%)
  • The overall re-scan rate was significantly higher before the cloud service was available (38%) vs after (28%)
  • If patient data was available from the cloud service, the re-scan rate dropped to 23% (??!)
  • Mean hospital charges for re-CT dropped from $1046 to $589

Bottom line: This study is interesting, but could use some improvement. It is older data (2009-2012), from the early days of these cloud services. Centers were a little less facile using them, which may have contributed to some of the soft numbers above. And the use of charge data rather than costs is old-school. 

Re-scanning a quarter of the patients, even when cloud images were available, is just not acceptable. However, this paper does suggest that there are real benefits, as re-scan rates and (presumably) costs should decrease. Radiation exposure would definitely drop, too.

The key to making a cloud sharing system work, or any other system for that matter (VPN, optical discs, etc), is to make it part of your PI program. Every transfer in needs to be scrutinized, and if an image transfer issue is found, quick feedback to the referring hospital needs to occur to ensure that it doesn’t happen again.

Reference: Implementation of an image sharing system significantly reduced repeat computed tomographic imaging in a regional trauma system. J Trauma 80(1):51-56, 2016.