Friday, February 10, 2012

Ketamine For Acute Pain Control

So, there's effective.  And then there's effective, but insane.  I am aware that low-dose continuous infusions of ketamine are excellent adjunctive therapies to decrease narcotic use in trauma and orthopedic patients, but I have never seen ketamine used in bolus form to treat acute pain in the out-of-hospital setting.

But, that's what we have.  After an initial 5mg IV bolus of morphine, patients were randomized to receive either additional morphine or ketamine boluses - 1 to 5mg of morphine every five minutes, or 10 to 20mg of ketamine every three minutes.  Pain medication was given per protocol until relief or adverse events.  And, the ketamine group was superior - pain scores dropped 5.6 points on the numerical verbal scale with ketamine and 3.2 with morphine.

However, the ketamine group also had a 39% incidence of adverse effects, compared with 14% of the morphine group.  The morphine group had mostly nausea, with one patient exhibiting a change in level of consciousness.  However, the ketamine group had multiple patients with decreased consciousness, disorientation, and emergence phenomena.  So, while the editor capsule summary states "Supplementing out-of-hospital opiods with low-dose ketamine is an effective strategy to mitigate trauma pain" he is technically correct, but the insanity of this strategy is trying to make an evidence-based decision about intracranial imaging after iatrogenically altering your patients prehospital.

What I appreciate best about this paper is how aggressive the paramedics were with treating pain - the patients receiving morphine averaged 14.4mg, with a standard deviation of 9.4mg!  I see my residents ordering 2mg at a time and it drives me nuts.

"Morphine and Ketamine Is Superior to Morphine Alone for Out-of-Hospital Trauma Analgesia: A Randomized Controlled Trial"

Wednesday, February 8, 2012

Finally, A Useful TPA Concept

Frequent readers of this site will be familiar with my distaste for TPA in stroke - not because I think it's a therapeutically invalid option, but mostly because its use is being promoted beyond its original scope, too many stroke mimics are receiving TPA, and the published literature supporting new "innovations" in TPA have a skewed interpretation of "safe".

This paper from Stroke is the first I've seen that finally tries to determine whether a patient will actually benefit from TPA in acute ischemic stroke, rather than chaining together studies in a logical fallacy to extend treatment to a larger population.  These authors have developed the "iScore" (no affiliation with Apple Computer), which was developed by logistic regression to predict outcomes in patients with ischemic stroke not treated with TPA.  The components include age, stroke severity, stroke subtype, and medical comorbidities in a scoring system that defines low (>50% good outcome), moderate (10-50%), and high-risk (<10%) groups.

These authors then apply the iScore in a retrospective fashion to their stroke database, looking both at their TPA recipients as well as propensity-matched patients in their non-TPA group.  Now, it's not exactly prospective, randomized, controlled, but it's an interesting trick that provides a limited comparison.  The stroke patients in the low-risk group had ~12% absolute outcomes benefit from TPA, the, the moderate group ~10% benefit, and the high-risk group ~2.6%.  There were no statistically significant benefits (or harms) from TPA in the high-risk group, but those patients were >90% disabled or dead at 30 days, regardless of therapy.

One weakness the authors point out in their study - it is sometimes clinically difficult to determine stroke subtype in the acute setting based solely off clinical presentation, particularly when baseline functional status is not perfect.  Regardless, it's nice to see a paper that looks at better individualizing the risk/benefit equation for TPA - seems as though the 400 patients in the high-risk group did not benefit from spending $2000 on alteplase or the associated increased DRG billing associated with it.  Money isn't free, after all....

"The iScore Predicts Effectiveness of Thrombolytic Therapy for Acute Ischemic Stroke"

Monday, February 6, 2012

Would Free Medications Help?

It's too bad this study doesn't actually look at what I would have hoped it would - but it's interesting, nonetheless.  One of my hospitals is a true safety-net hospital and we see, repeatedly, repeatedly, repeatedly, the complications of neglected chronic disease.  One of our frequent laments is whether the costs of recurrent acute hospitalization wouldn't be prevented a hundred times over if we'd simply sink some costs into preventative maintenance care, free medications, etc.

This study almost looks at that.  This is from the NEJM which compared the outcomes of patients following myocardial infarction, and they follow a group which receives completely free medication and a group that does not.  Unfortunately, the group that does not receive free medications is still receiving heavily subsidized medication support, and is only responsible for a co-pay.

Despite only needing to come up with a co-pay, there's a significant difference in medication compliance, with an average absolute difference in full adherence with medications of ~5-6%.  With this minimal absolute difference in adherence, the full adherence group had significantly fewer future vascular events - mostly from stroke and myocardial infarction - approximately a 1% absolute decrease.  There was a non-significant decrease in total costs associated with the patients who were on the full-coverage medication plan.

Now, they don't follow-up any medication-related adverse events, so this is the most optimistic interpretation of benefits of full-coverage, but it would seem that it is overall cheaper and more beneficial to supply medications for free.  And, it makes me wonder what the results of a similar cost/health-benefit study would show in our safety-net population.

"Full Coverage for Preventive Medications after Myocardial Infarction"