Month: November 2013

Bivalrudin Trumps Heparin (Or Not)(Who Knows?)

10 out of 10 physicians employed by the Medicines Company approved this message.

Straight out of Jeff Drazen’s unbiased news pipeline, a treatment you might now start seeing more of in the Emergency Department: bivalrudin (Angiomax) for anticoagulation prior to PCI in the setting of STEMI.  In this trial, 2,231 patients across Europe were randomized pre-hospital (or at non-PCI hospitals) to either bivalrudin or heparin plus optional glycoprotein IIb/IIIa inhibitor.  The primary outcome, as typical of these sorts of trials, is another muddled composite: death from any cause, re-infarction (MI), or major bleeding not related to CABG.

Oh, wait, that was the original primary outcome.  In December of 2012, over three-quarters of the way through the enrollment period, the Medicines Company dropped re-infarction (MI) from the primary outcome.  It may or may not be a coincidence re-infarction due to stent thrombosis favored the control intervention, but I will leave that speculation up to the astute reader.  Regardless, the new final composite endpoint favored bivalrudin: 5.1% to 8.5%.  However, this outcome also depends on their own unique definition of “major bleeding”, which is different from TIMI and GUSTO.  If the TIMI and GUSTO definitions are used, the trend towards reduced bleeding with bivalrudin is still there, but the absolute differences become trivial and the overall primary outcome (original or eventual) is a wash.  Finally, this may all simply be a straw-man comparison for the safety outcome, as it’s reasonable to ask whether 69% of cases ought to be receiving prehospital glycoprotein IIb/IIIa inhibitor (an AHA Class IIb recommendation).

However, better questions may be – as are a recurring theme for the NEJM – do you trust the results of an open-label trial sponsored by the manufacturer, designed by the manufacturer, with data stored and dispensed to the academic oversight group by the manufacturer?  Are you less or more convinced when four authors are employed by the manufacturer, and the manufacturer employed a scientific communications firm for “editorial support”?  Why is NEJM publishing a trial that changed its primary outcome in clinicaltrials.gov – even, as the authors claim, to “reduce the necessary sample size”?

Physicians ought to be outraged at this transparent and unbalanced pharma shill – but, such occurrences have become so commonplace, it’s hard to not just surrender to lassitude.  Bivalrudin doubtless has an advantage in some specific subgroup, but with this sort of offal clogging the evidence, we’ll never really know.

“Bivalirudin Started during Emergency Transport for Primary PCI”
www.ncbi.nlm.nih.gov/pubmed/24171490

Unicycles, Not All Fun And Games?

Finally a study on Unicycles! According to Dr. Marvin Wang, the author of the recently published article “Unicycle Injuries In the United States”, his chart review of the National Electronic Injury Surveillance System (NEISS) is the entirety of the world’s literature on unicycle injuries. To my utter disappointment there were zero cases of falls from a tight rope or burns from a mishandled flaming juggling pin. Even the author himself observes that unicycles, once exclusively ridden by professional “circus folk” and acrobats, have now become primarily an amateur endeavor.
Ironically the same inherent mechanics and “sense of danger” that made the unicycle a popular circus act, makes it far safer than its two-wheeled cousin when used by the general public. Because of its single wheel, riders are far less capable of attaining high speeds and it is therefore infrequently used as a functional means of transportation. Given this lack of functional utility, riders of unicycles seem to have escaped the more serious types of cycle accidents such as high-speed crashes and collisions with motor vehicles. Upon review of the 85 cases of documented unicycle injuries found in the NEISS database from 1991 to 2010, the author extrapolates that 168 people a year visit the emergency department for unicycle related injuries in the United States. The most common injuries acquired were extremity fractures, sprains and strains. Very few head and neck injuries occurred, and the majority of these were scraps and abrasions.
The biggest weakness of this study is that we are unable to determine a denominator. Since we do not know what percentage of the US population at any time are riding unicycles, we are unable to quantify the risk of riding such a contraption. It may be that only a small percentage of riders will sustain an injury that requires an ED visit. Conversely it is possible that the risk is much higher. If you do decide to mount one of these single wheeled cycles you may be taking your life, or at least your limb into your own hands…
“Unicycle Injuries In the United States”
www.ncbi.nlm.nih.gov/pubmed/23871477
For more nihilism, emergency medicine and the art of doing nothing see emnerd.com and @CaptainBasilEM

Unicycles, Not All Fun And Games?

Finally a study on Unicycles! According to Dr. Marvin Wang, the author of the recently published article “Unicycle Injuries In the United States”, his chart review of the National Electronic Injury Surveillance System (NEISS) is the entirety of the world’s literature on unicycle injuries. To my utter disappointment there were zero cases of falls from a tight rope or burns from a mishandled flaming juggling pin. Even the author himself observes that unicycles, once exclusively ridden by professional “circus folk” and acrobats, have now become primarily an amateur endeavor.
Ironically the same inherent mechanics and “sense of danger” that made the unicycle a popular circus act, makes it far safer than its two-wheeled cousin when used by the general public. Because of its single wheel, riders are far less capable of attaining high speeds and it is therefore infrequently used as a functional means of transportation. Given this lack of functional utility, riders of unicycles seem to have escaped the more serious types of cycle accidents such as high-speed crashes and collisions with motor vehicles. Upon review of the 85 cases of documented unicycle injuries found in the NEISS database from 1991 to 2010, the author extrapolates that 168 people a year visit the emergency department for unicycle related injuries in the United States. The most common injuries acquired were extremity fractures, sprains and strains. Very few head and neck injuries occurred, and the majority of these were scraps and abrasions.
The biggest weakness of this study is that we are unable to determine a denominator. Since we do not know what percentage of the US population at any time are riding unicycles, we are unable to quantify the risk of riding such a contraption. It may be that only a small percentage of riders will sustain an injury that requires an ED visit. Conversely it is possible that the risk is much higher. If you do decide to mount one of these single wheeled cycles you may be taking your life, or at least your limb into your own hands…
“Unicycle Injuries In the United States”
www.ncbi.nlm.nih.gov/pubmed/23871477
For more nihilism, emergency medicine and the art of doing nothing see emnerd.com and @CaptainBasilEM

The Trauma Log Roll is Dead

Among unproven interventions, back-boarding, cervical collars, and log-rolling have been part of the dogma of trauma since Alfred Nobel invented the electric slide.  We’ve finally started to put an end to uncomfortable and unwarranted back-boarding, we’ve re-designed cervical collars, and this article takes on log-rolling.  The assertion of these authors is clinical examination of an otherwise alert major trauma patient is unreliable, does not obviate imaging, and may thereby be omitted from the initial secondary survey.

Unfortunately, this is a very specific, limited, retrospective registry review.  Only patients from the trauma registry at the Alfred Hospital were included: major trauma (ISS >15) and admitted for 24 hours, or isolated thoracolumbar injuries requiring 72 hours of hospitalization.  This identified 1,161 patients with thoracolumbar fractures, and these authors further pared it down to 538 who were GCS >15 as their proxy for potentially reliable examination.  How many of these alert, appropriate trauma patients with thoracolumbar fractures complained of pain on log-roll and spinal palpation?

60.3%.

So, yes, if the clinical examination is only 60.3% sensitive for significant thoracolumbar fractures, then we ought to stop bothering to log-roll our patients.  But, generalizing the evidence from this retrospective review in a highly selected population is grossly irresponsible.  It is reasonable, as the accompanying letter states, if the decision has already been made in a major trauma to progress to full-body computed tomography – a test more sensitive and specific for spinal fractures than clinical examination – log-roll and complete physical examination may be deferred.  The theoretical risks to log-roll – lack of true thoracolumbar stability, possibility of disturbing internal hemostasis – if there is no benefit, are appropriate considerations if physical examination does not change clinical evaluation.  It is, however, excessive to universally posit, as the letter authors do, “Log-rolling a blunt major trauma patient is inappropriate in the primary survey.”

“Can initial clinical assessment exclude thoracolumbar vertebral injury?”
www.ncbi.nlm.nih.gov/pubmed/22915226‎

“Log-rolling a blunt major trauma patient is inappropriate in the primary survey”
www.ncbi.nlm.nih.gov/pubmed/24136122‎

Guest Blogger – Rory Spiegel

A few of you might have noticed this week we had a couple guest posts from Dr. Spiegel, affiliated with Newark Beth Israel Emergency Medicine.  He’s been doing great work on his own blog site, emnerd.com, taking a deeper dive into some of the newly published medical literature.  You can also follow him on Twitter:  @CaptainBasilEM

If you’re interested in guest posting on a new or fascinating piece of the Emergency Medicine or general medical literature, send along an e-mail and we’ll chat!

Brainwashing With Oxytocin

Placebo mechanisms are well-known.  As Ken Milne of The Skeptic’s Guide is happy to tell you, the power of belief is strong.

But, it turns out it can be made stronger.

This rather fascinating study evaluates the power of oxytocin.  Oxytocin has been linked to processes of empathy, trust, and social learning.  These elements, as noted by the authors, are key to patient-physician interactions.  So, they perform a little study to see whether oxytocin can enhance the placebo effect – tapping into the elements of physician empathy and trust.

In the experiment, a technician applied either oxytocin or saline intranasally.  Then, they applied the same inert cream to two sites on each patient’s forearm, telling the patient one was the control, and one was the active drug.  Patients were tested using heat as painful stimuli on a visual analog scale.

There was, as expected, a placebo effect.  In the saline group, the mean VAS difference between the inert “control” cream and the inert “placebo” cream was 7mm.  In the oxytocin group, however, the mean VAS difference between sites was 13mm.  In their small group of patients, this result met statistical significance – and thus the authors conclude oxytocin enhances the placebo response.

Not precisely certain how this would be applied clinically, but it’s a fascinating little research letter.

“Effect of Oxytocin on Placebo Analgesia: A Randomized Study”
http://www.ncbi.nlm.nih.gov/pubmed/24150470