The Pentagon and the University of Pittsburgh have developed a new technique for growing functional muscle in vivo. The process starts with insertion of an extracellular matrix containing growth factor proteins from pig bladders. Stem cells move to the area and begin the process of wound repair and tissue growth, which normally does not occur in mature muscle.
The really interesting thing about this process is that, after intensive rehab begins, not only does the muscle grow back, but also tendons and nerves to innervate the muscle! The process has been used successfully in four patients so far.
Bottom line: This may become a new standard of care in the next few years. It will simplify soft tissue reconstruction in mangled extremities and motorcycle injuries, to name a few.
Yesterday I wrote about one reader’s experience with a trauma patient on Dabigatran. 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.
Following is a comment I received about one reader’s experience with this drug. Why don’t we just set some hard parameters or age limits on the use of such drugs? I’ll provide the opposing view tomorrow.
“So far, one clinical trauma experience- 70+ yo male cut his fingers working with a model airplane engine; on dabigatran. Blood loss nearly 1 L., no control of bleeding w. 2 hours of tourniquet time. Required microvascular ligation of digital vessels. Impressively powerful anticoagulant.
You have to be aware of dosing times to know how long anti-coag effect is likely to endure. Lab tests of little help. No demonstrated efficiacy of Factor VIIa or PCC; in fact, PCC has been shown not to help in one trial. It is effective with Xarelto, though.
Our blood bank stays up at night worrying about this drug, with good reason, since we do our own collections.
Clinicians prescribing this drug should look at bleeding risk scoring systems (HEMORR2HAGE, HAS-BLED) as well as the CHADS2 score before deciding to use this drug.
I suspect it will be ultimately replaced by the Factor Xa inhibitors. N.B- New Zealand has been reporting a myriad of bleeding issues with this drug. Since it is a relatively closed system, their experience should be a bellweather.”
“If a tree falls in a forest and no one is around, does it make a sound?”
There is a clinical corollary to this question in the field of trauma:
“If an injury exists but no one diagnoses it, does it make a difference (if there would be no change in treatment)?”
Here’s an example. On occasion, my colleagues want to order diagnostic studies that won’t make any clinical difference, in my opinion. A prime example is getting a chest CT after a simple blunt assault. A plain chest xray is routine, and if injuries are seen or the physical exam points to certain diagnoses, appropriate interventions should be taken. But adding a chest CT does not help. Nothing more than the usual pain management, pulmonary toilet, and an occasional chest tube will be needed, and those can be determined without the CT.
Trauma professionals need to realize that we don’t need to know absolutely every diagnosis that a patient has. Ones that need no treatment are of academic interest only, and can lead to accidental injury if we look for them too hard (radiation exposure, contrast reaction, extravasation into soft tissues to name a few). This is how we get started on the path to “defensive medicine.”
Bottom line: Think hard about every test you order. Consider what you are looking for, what you might find, and if it will change your management in any way. If it could, go ahead. But always consider the benefits versus the potential risks, or what I call the “juice to squeeze ratio.”
George Berkeley, A Treatise Concerning the Principles of Human Knowledge, 1734, section 45.
paraphrased by William Fossett, Natural States, 1754.
The ED is a fast-paced environment where things must happen quickly at times. This makes it a ripe environment for errors. A recent study looked at one possible way of decreasing the number of medication errors in a Level I trauma center.
A prospective observational study was carried out in the ED, where pharmacists were on duty and attended all trauma activations for 10 hours each day. No pharmacist was present the rest of the time. The potential errors that were identified consisted of any of the following:
medication ordered but not given
medication given but not ordered
delay in administration
Nearly 700 patient encounters were evaluated, with about one third seen when the pharmacist was present, and two thirds when they were away (makes sense given their coverage hours). The demographics of the patient groups were the same.
There was a huge difference in the number of medication errors! Only 6 errors (3%) occurred when pharmacists were present, but 137 occurred (30%) when they were not. An odds-ratio calculation showed that medication errors were 13.5 times more likely to occur on shifts when pharmacists were not present in the ED.
Bottom line: It’s helpful to have another set of eyes, not focused on the patient’s injuries, looking after critical medications. The error rate is so much lower with a pharmacist present that it must be cost effective to provide them 24/7. Time for another study!
Reference: On-site pharmacists in the ED improve medical errors. Am J Emerg Med Jun 10, 2011 (epub ahead of print).
Home of the Trauma Professional's Blog
Do you want to get a daily email every time there’s a new post? See what I’m up to.