Category Archives: General

Trauma Mythbusters: NSAIDs And Fracture Healing

Trauma hurts like hell. Over the years, we’ve developed quite a few ways of combating this pain. A number of drug classes have been developed to reduce it. One of the more common non-narcotic drug classes are the NSAIDs. As I’ve mentioned before, every drug has dozens of effects. Drug companies market a particular medication based on one of the predominant effects. All the others are considered side effects.

NSAIDs are not unique; they have lots of side effects as well. In 2003, several papers brought to light possible interactions between these drugs and fracture healing. Specifically, there were questions about these drugs interfering with the healing process and of increasing the number of delayed unions or nonunions. But once again, how convincing were these papers, really?

It would seem to make sense that NSAIDs could interfere with bone healing. This  process relies heavily on the regulation of osteoblast and osteoclast function, which itself is regulated by prostaglandins. Since prostaglandins are synthesized by the COX enzymes, COX inhibitors like the NSAIDs should have the potential to impair this process. Indeed, animal studies in rats and rabbits seem to bear this out.

But as we have seen before, good animal studies don’t always translate well to human experience. Although a study from 2005 suggested that NSAID administration in older patients within 90 days of injury had a higher incidence of fracture nonunion, the study design was not a very good one. It is equally likely that patients who required these drugs in this age group may have been at higher risk for nonunion in the first place.

In fact, there are no large, prospective randomized studies that have explored the effect of short-term or long-term NSAID administration on fracture repair. But there have been several smaller studies that showed absolutely no effect on nonunion with short-term administration of this drug class. Yet the dogma that leads us to avoid giving these drugs persists.

A recent analysis looked at the quality of the published research, both for and against NSAID usage in fracture patients. They used the Coleman Methodology Score, which evaluates study size and type, mean followup, detailed description of treatment, subject selection, outcomes, and outcome assessment. The maximum score was 100. 

Here are the factoids:

  • There were 4x as many total subjects in the “NSAIDS are okay” papers than in the “avoid NSAIDS” papers
  • The quality of the “NSAIDS are okay” papers were significantly higher than “avoid NSAIDS” group (59 vs 40)
  • Interestingly, the “avoid NSAIDS” papers are cited twice as often
  • All of the reviews ended with my pet peeve catch phrase “further (good) research is needed”

Bottom line: Once again, the animal data is clear but the human data is not. Although there are theoretical concerns about their use, there is not enough solid risk:benefit information to abandon short-term NSAID use in patients who really need them. NSAIDs can and should be prescribed in patients with short-term needs and simple fractures.

References:

  1. Effects of nonsteroidal anti-inflammatory drugs on bone formation and soft-tissue healing. J AM Acad Orthop Surg 12:139-43, 2004.
  2. Effect of COX-2 on fracture-healing in the rat femur. J Bone Joint Surg Am 86:116-123, 2004.
  3. Effects of perioperative anti-inflammatory and immunomodulating therapy on surgical wound healing. Pharmacotherapy 25:1566-1591, 2005.
  4. Pharmacological agents and impairment of fracture healing: what is the evidence? Injury 39:384-394, 2008.
  5. High dose nonsteroidal anti-inflammatory drugs compromise spinal fusion. Can J Anaesth 52:506-512, 2005.
  6. Nonsteroidal Anti-Inflammatory Drugs and Bone-Healing: A Systematic Review of Research Quality. JBJS Rev 4(3), 2016.

Ever Wonder Where The Golden Hour Came From?

Everywhere you turn in the trauma and EMS world, you run into the concept of the “golden hour.” Basically, it refers to the idea that it’s important to get an injured patient to definitive care promptly, or mortality begins to rise. It has been used to justify a lot of what we do in trauma care and trauma systems. But where did this come from? And is it true?

The BTLS course attributes the term to R Adams Cowley from the ShockTrauma Center in Baltimore. Unfortunately, no references are given. A biography of Cowley entitled Shock-Trauma names him the author of the term, basing it on dog research. No references were given.

A review of Cowley’s research reveals a few tidbits. A case series of patients implies that speed is good, but does not analyze time to definitive care. It does reference older work by other authors, but once again, no relationship between timing and outcome is evaluated.

A textbook edited by Cowley contains a reference to an article about “Cowley’s golden hour.” This article contains a statement that “patients are assumed to be dying and much of the golden hour has passed.” It goes on to state that the first 60 minutes after injury determines the patient’s mortality. It, in turn, refers to another of his earlier articles. This one states that “the first hour after injury will largely determine a critically injured person’s chance for survival.” No data or reference is given.

Bottom line: The concept of the “golden hour” has taken on a life of its own. Yes, it’s a good idea. And yes, there is some actual data to support it, although the quality is somewhat lacking. But this does point out the need to question everything, even some of our most deeply held beliefs. They are not always what they seem to be.

Reference: The Golden Hour: scientific fact or medical urban legend? Acad Emerg Med 8(7):758-760, 2001.

The Rectal Exam In Trauma Continues to “Pass”?

This topic continues to come up from time to time. I still see trauma programs that perform the good, old-fashioned digital rectal exam on nearly every trauma patient. But is it really necessary?

In the not so distant past, it was standard operating procedure to perform a digital rectal exam in all major trauma patients. The belief had always been that valuable information about blood in the GI tract, the status of the urethra, and the neuro exam (rectal tone) could be gleaned from this exam.

Unfortunately, a finger in the bum also serves to antagonize or even further traumatize some patients, especially those who may be intoxicated to some degree. On a number of occasions I have seen calm patients become so agitated by the rectal exam that they required intubation for control.

So is it really necessary? A study in 2001 conducted over a 6 month period (1) showed that the rectal exam influenced management in only 1.2% of cases. The authors felt that there was some utility in 3 special cases:

  • Spinal cord injury – looking for sacral sparing
  • Pelvic fracture – looking for bone shards protruding into the rectum
  • Penetrating abdominal trauma – looking for gross blood

A more recent 2005 study (2) was also critical of the rectal exam and found that using “other clinical indicators” (physical exam and other diagnostic study information) was at least equivalent, changing management only 4% of the time. They concurred with the first two indications above as well.

Bottom line: For most major trauma patients, the rectal exam is not worth the patient aggravation it causes. I still recommend it for the 3 special cases listed above, however, as there are no equivalent exams for these potentially serious patient problems. And remember, DON’T do it while the patient is in the logroll position. No patient likes a rectal exam, so they’ll do their best to defeat your puny attempt at spine precautions if you have them on their side. Supine, frog-leg only.

References:
1. Porter, Urcic. Am Surg. 2001 May;67(5):438-41.
2. Esposito et al. J Trauma. 2005 Dec;59(6):1314-9.

Orthopedic Hardware And TSA Metal Detectors

Many trauma patients require implantable hardware for treatment of their orthopedic injuries. One of the concerns they frequently raise is whether this will cause a problem at TSA airport screening checkpoints (Transportation Safety Administration).

The answer is probably “yes.” About half of implants will trigger the metal detectors, and these days that usually means a pat down search. And letters from the doctor don’t help. It turns out that overall, 38% are detected when the scanner is set to low sensitivity and 52% at high sensitivity.

Here is a more detailed breakdown:

  • Lower extremity hardware is detected 10 times more often than upper extremity or spine implants
  • 90% of total knee and total hip replacements are detected
  • Upper extremity implants such as shoulder, wrist and radial head replacements are rarely detected
  • Plates, screws, IM nails, and wires usually escape detection
  • Cobalt-chromium and titanium implants trigger alarms more often than stainless steel

If your patient knows that their implant triggers the detectors, they have two options: request a patdown search, or volunteer to go through the full body millimeter wave scanner. This device looks at everything from the skin outwards, and will not “see” the implant and is probably the preferred choice. If they choose to go through the metal detector and trigger it, they are required to have a patdown. Choosing to go through the body scanner after setting off the detector is no longer an allowed option.

Reference: Detection of orthopaedic implants in vivo by enhanced-sensitivity, walk-through metal detectors. J Bone Joint Surg Am. 2007 Apr;89(4):742-6.

Liquid Plasma vs FFP: Impact On Your Massive Transfusion Protocol

In my last post, I discussed the growing number of choices for plasma replacement. Today I’ll look at some work that was done that tried to determine if any one of them is better than the others when used for the massive transfusion protocol (MTP).

As noted last time, fresh frozen plasma (frozen within 8 hours, FFP) and frozen plasma (frozen within 24 hours, FP) have a shelf life of 5 days once thawed. Liquid plasma (never frozen, LQP) is good for the 21 days after the original unit was donated, plus the same 5 days, for a total of 26 days.

LQP is not used at most US trauma centers. It is more commonly used in Europe, and a study there suggested that the use of thawed plasma increased short term mortality when compared to liquid plasma. To look at this phenomenon more closely, a group from UTHSC Houston and LSU measured hemostatic profiles on both types of plasma at varying times during their useful life.

All products were analyzed with thromboelastography (TEG) and thrombogram, and platelet count and microparticles, clotting factors, and natural coagulation inhibitors were measured. They chose 10 units of thawed FFP and 10 units of LQP, and assayed them every 5 days during their useful shelf life.

Here are the factoids:

  • Platelet counts were much higher in day 0 LQP (75K) vs day 0 thawed plasma (7.5K). Even at end of shelf life, the LQP was 1.5x higher than thawed (15K vs 10K).
  • Thrombogram showed that LQP had higher endogenous thrombin production until end of shelf life
  • TEG demonstrated that LQP had a higher capacity to clot that gradually declined over time. It became similar to thawed plasma at the end of its shelf life.
                         (TEG MA for liquid (LQP) and thawed (TP) plasma
  • Most clotting factors remained stable in LQP, with the exception of Factors V and VIII, which slowly declined

Bottom line: Liquid plasma sounds like good stuff, right? Although there are a few flaws in the collection aspect of this study, it gives good evidence that never frozen plasma has better coagulation properties when compared to thawed plasma. Will this translate into better survival when used in the MTP for trauma? One would think so, but you never really know until you try it. Our hospital blood bank infrastructure isn’t prepared to handle this product yet, for the most part. What we really need is a study that shows the survival advantage when using liquid plasma compared to thawed. But don’t hold your breath. It will take a large number of patients and some fancy statistical analysis to demonstrate this. I think we’ll have to look to our military colleagues to pull this one off!

Reference: Better hemostatic profiles of never-frozen liquid plasma compared with thawed fresh frozen plasma. J Trauma 74(1):84-91, 2013.