All posts by TheTraumaPro

Best Of: Spine Immobilization in Penetrating Trauma: More Harm Than Good?

The EMS standard of care for blunt trauma patients has been to fully immobilize the spine before transporting to an emergency department. This is such a common practice that it is frequently applied to victims of penetrating trauma prior to transport.

A recent study in the Journal of Trauma calls this practice in question, and suggests that it may increase mortality! The authors reviewed data in the National Trauma Data Bank, looking at information on penetrating trauma patients. They found that approximately 4% of these patients underwent spine immobilization.

Review of mortality statistics found that the mortality in non-immobilized (7%) doubled to 14% in the immobilized group!

The authors also found that medics would have to fail to immobilize over 1000 patients to harm one who really needed it, but to fully immobilize 66 patients who didn’t need it to contribute to 1 death.

Although this type of study can’t definitely show why immobilization in these patients is bad, it can be teased out by looking at related research. Even the relatively short delays caused by applying collars and back boards can lead to enough of a delay to definitive care in penetrating trauma patients that it could be deadly. The assumption in all of these patients is that they are bleeding to death until proven otherwise.

A number of studies have suggested that a “limited scene intervention” to prehospital care is best. The assumption is that the most effective treatment can only be delivered at a trauma center, so rapid transport with attention to airway, breathing and circulation is the best practice.

While interesting, some real-life common sense should be applied by all medics who treat these types of patients. The reality is that it is nearly impossible to destabilize the spine with a knife, so all stab victims can be transported without a thought to spine immobilization. Gunshots can damage the spine and spinal cord, so if there is any doubt that the bullet passed nearby, at least simple precautions should be taken to minimize spine movement.

Reference: Spine Immobilization in Penetrating Trauma: More Harm Than Good? Haut et al, Johns Hopkins. J Trauma 68(1): 115-121, 2010.

Taking A Few Days Off?

Yes, I’m traveling today through the end of next week. Of course, I’ll be keeping my eyes open for interesting trauma stuff. If I don’t find anything really interesting, I’ll be running some “best of” columns that highlight good stuff from the past.

I’ll be attending EAST after that, and I’ll be tweeting from the meeting like a madman.

I will be checking in regularly through Twitter via FourSquare, so if you’re interested, you can track what I’m up to. 

Thanks for reading!
Michael 

Hypothermia and Massive Transfusion

Tuesday, I talked about a new notion of using profound hypothermia to save critically injured trauma patients. Since this concept is not yet ready for prime time, we still have to treat hypothermia as our enemy. Most trauma centers have established massive transfusion protocols that detail the use and ratios of specific blood components to avoid fatal anemia and coagulopathy. But do we pay enough attention to hypothermia?

A multicenter study was carried out that will be reported at the upcoming EAST meeting in January. They looked at patients who received massive transfusion (>= 10u PRBC in 24 hours) and looked at their lowest temperature during that 24 hour period. 

They found that as temperature decreased, shock parameters, coagulopathy, injury severity and transfusion requirements increased significantly. Specifically, if a temperature of <34C doubled mortality risk, and this effect was most pronounced in patients who received relatively less plasma.

Bottom line: Temperature is still very important, and hypothermia must be avoided at all costs. This is true in the ED and the OR. Allowing temperature to drop below 34C significantly increases mortality and is at least as important as giving enough FFP to correct coagulopathy from dilution.

Related post:

Reference: Hypothermia in massive transfusion: are we not paying enough attention to it? Poster 2, EAST 25th Annual Assembly, Jan 2012.

Induced Hypothermic Arrest In Patients Bleeding To Death?

Here’s an interesting note out of the University of Pittsburgh. They are preparing to engage in a study to look at the role of hypothermic arrest as a way to salvage trauma patients who are bleeding to death. Sometimes we encounter catastrophic injuries that are exceeding difficult to stop the bleeding. Some vascular injuries within the abdomen come to mind, particularly retrohepatic vena cava injuries.

So what would happen if you rapidly reinfused the patient with cold preservative instead of more blood? The idea is to stop the heart and induce profound hypothermia that would essentially put the brain and other key organs into suspended animation. This might provide a period of time to do the needed repairs, but not worry about the imminent danger of brain death.

Sam Tisherman, the principal investigator, terms this scenario EPR or “emergency preservation and resuscitation” instead of CPR. The desired temperature after cardiac arrest is 50 degrees F, or 10 degrees centigrade. Animal trials have shown promise.

Bottom line: It will be interesting to see how this goes. We’ve tried hypothermia for heart attacks, head injury, and a number of other clinical problems. Unfortunately after initial enthusiasm, they’ve generally not lived up to their billing. It seems counterintuitive to use a maneuver guaranteed to produce coagulopathy to save somebody who is bleeding. But sometimes this type of bold thinking results in life-saving breakthroughs.

Percutaneous Tracheostomy Without The Bronchoscope

It’s always nice to find an article that supports your biases. I’ve been doing percutaneous tracheostomy since the 1990’s, and have used a variety of kits and equipment. Some of these turned out to be rather barbaric, but the technique is now quite refined. 

A routine part of the procedure involved passing a bronchoscope during the procedure to ensure that the initial needle was placed at the proper level and in the tracheal midline. It was also rather frightening to watch the trachea collapse when the dilators were inserted.

I abandoned using the bronchoscope in this procedure about 10 years ago. It was an annoyance to get the bronchoscope cart and a respiratory therapist to help run it. And to find someone available to pass the scope while I did the trach. So I added a little extra dissection to the technique, directly visualizing the trachea at the desired location. From then on, I had no need to see the puncture from the inside because I could see it quite well from the outside!

An article in the Journal of Trauma this month shows that this technique works just as well without the scope. The authors looked at their own series of 243 procedures; 32% were done with the bronchoscope, 68% without. There were 16 complications overall, and the distribution between the bronch and no-bronch groups was equal.

Bottom line: In general, the bronchoscope is not needed in most percutaneous tracheostomy procedures. It adds complexity and expense. However, there are select cases where it can be helpful. Consider using it in patients in a Halo cervical immobilizer, the obese, or in patients with known difficult airway anatomy. And always do the more difficult ones in the OR, not the ICU.

Reference: Percutaneous tracheostomy: to bronch or not to bronch – that is the question. J Trauma 71(6):1553-1556, 2011.