Friday, June 22, 2007

Fixin' Funyun Trauma

Jes fer fun, try something --- take one of those terrible-for-your-heart Funyuns (yes, I know you've had them at some point), hold it between your index finger and thumb, and then squeeze. When it breaks and sprays crumbs all over the place, it will never break in only one place. It's a ring, and unless force is applied in an outward fashion, rings break in at least two locations. Unfortunately, in an automobile accident, your pelvis acts not unlike that cracking Funyun --- it's a ring, albeit one containing a fair amount of expensive real estate and a treasure trove of blood vessels.

Without getting too involved in the how and why of what happens with pelvic fractures -- the bony and ligamentous structure disruption in anterior-posterior and lateral shear -- suffice it to say that they range from relatively mild to very severe. Significant disruption of the pelvic ring can result in significant bleeding, which is almost exclusively venous in nature. Since veins don't have much in the way of any ability to constrict like arteries, and since there is no "limited space" compartment that would fill up and allow the bleeding to stop and develop a clot, patients with big pelvic fractures can really empty themselves of a substantial amount of blood in a short period of time.

We have learned that the best way to slow that bleeding down to a trickle in most cases is to put Humpty Dumpty back together again into a more normal configuration. A good way to do that is to put on a pelvic fixation device ("external fixator"), which resembles nothing so much as a set of Tinker Toys drilled into the iliac crests anteriorly with bars across the anterior pelvis. This technique works pretty well in most instances, and has been utilized widely for years.

The one little problem with placing an "ex fix" is that it takes time --- time to get the orthopedist to the hospital, to locate all of the Tinker Toy sets to place it, and to get the patient to the operating room where it is almost always placed. In a patient who may be bleeding not only from pelvic fractures, but possibly has a splenic injury, a femur fracture, etc., ongoing blood loss is not the best possible scenario. Uncontrolled hemorrhage leads to acidosis, consumption of coagulating factors in the blood, temperature loss......and then if not reversed, more bleeding that can't be stopped. A multiply injured patient can seem at first to be sailing rather smoothly on relatively rough seas, but in reality is a boat slowly circling the edge of a gigantic whirlpool. They can get "sucked down" and "circle the drain" quickly, and it takes a whole lotta work to get them pulled back out.

Other, quicker options to reduce the pelvic fracture started popping up, such as using MAST trousers (didn't work well) or towel clipping a sheet around the pelvis (quick, easy, but doesn't apply uniform pressure). So, some Smart GuysTM devised a string-and-velcro device to accomplish the same thing (there are actually a few on the market). The T-POD device allows rapid placement, easy access to the patient, and uniform circumferential compression of the pelvis. Here are a few photos from their web site:

But, does it work? Do these types of devices deliver superior (or at least comparable) results to external fixation? A nice study from the University of Tennessee Health Science Center in Memphis tried to compare apples to apples. Although it was a retrospective study, the authors did find the pelvic orthotic device (POD) to

  1. decrease 24 and 48 hour transfusion requirements
  2. decrease hospital length of stay
  3. decrease ventilator associated pneumonia rates (likely due to decreased transfusion needs
in comparison to external fixation. Even given the problems interpreting retrospective data, this was a good study that showed that this rapid, inexpensive technique has the potential to do some serious good in the trauma suite. Not too shabby for a simple device that resembles a corset (and don't think I would put a picture of a corset up here; this is a family blog!).