Research and Reviews in the Fastlane 144

Research and Reviews in the Fastlane

Welcome to the 144th edition of Research and Reviews in the Fastlane. R&R in the Fastlane is a free resource that harnesses the power of social media to allow some of the best and brightest emergency medicine and critical care clinicians from all over the world tell us what they think is worth reading from the published literature.

This edition contains 6 recommended reads. The R&R Editorial Team includes Jeremy Fried, Nudrat Rashid, Soren Rudolph, Justin Morgenstern, Anand Swaminathan and, of course, Chris Nickson. Find more R&R in the Fastlane reviews in the R&R Archive, read more about the R&R project or check out the full list of R&R contributors

This Edition’s R&R Hall of Famer

Cardiology
R&R Hall of Famer - You simply MUST READ this!
Ortiz M, et al. Randomized comparison of intravenous procainamide vs. intravenous amiodarone for the acute treatment of tolerated wide QRS tachycardia: the PROCAMIO study. European heart journal. 2016. PMID: 27354046

  • The evidence for amiodarone has always been on the weak side. This is a good paper that should be practice changing for some people. It is a multicenter, randomized trial comparing amiodarone (5mg/kg over 20 minutes) to procainamide (10mg/kg over 20 min) in 74 adult patients with hemodynamically stable ventricular tachycardia. Procainamide was better. The primary outcome of cardiac adverse events (mostly hypotension requiring cardioversion), occurred in 9% of the procainamide group and 41% of the amiodarone group (odds ratio 0.1, 95%CI 0.03-.06, p=0.006). In terms of stopping the v.tach, procainamide worked 67% of the time as compared to only 38% with amiodarone (OR = 3.3; 95% CI 1.2-9.3; P = 0.026). Unfortunately, the trial was originally designed to include 300 patients, but they stopped it early because of slow recruitment. However, this comparison may not be all that relevant to you if, like me, you prefer to go straight to electricity in these patients.
  • Recommended by Justin Morgenstern
  • Further reading The Case of the Dysrhythmic Heart (EM Nerd)

The Best of the Rest

Education
R&R Hot Stuff - Everyone’s going to be talking about thisR&R Hot Stuff - Everyone’s going to be talking about this
Wray CM, Loo LK. The Diagnosis, Prognosis, and Treatment of Medical Uncertainty. Journal of graduate medical education 2015. PMID: 26692960

  • This is an nice editorial reviewing uncertainty in medicine that is worth reading. They point out that no matter how much information we are able to gather, the inherent complexity of human life, the variability of presentations, and the fact that we cannot predict the future will always leave us with an intrinsic uncertainty. They point out the problem in medical education in that we value certainty from our students, and present them with black and white multiple choice exams that don’t well represent the grey of real life medicine. They close with an excellent quote from Sir William Osler: “A distressing feature in the life of which you are about to enter … is the uncertainty which pertains not alone to our science and art, but the very hopes and fears which make us men. In seeking out the absolute truth we aim for the unattainable, and must be content with finding broken portions.’’
  • Recommended by Justin Morgenstern

Emergency Medicine

Bijur PE, et al. Temperature measurement in the adult emergency department: oral, tympanic membrane and temporal artery temperatures versus rectal temperature. Emerg Med J 2016. PMID: 27334759.

  • Does your patient have a fever? This seemingly simple question can oftentimes be difficult to answer. These authors attempted to answer which of the various non invasive methods (oral, tympanic, temporal artery) best answers that question when compared with rectal temperature as the gold standard. Surprisingly, tympanic membrane measurement was the most precise with a cutoff of 37.5C (99.5F) having high specificity and sensitivity. Previously, I have asked for an oral temperature when I question the accuracy of the tympanic membrane measurement. It seems time to let go of that practice and simply move to the more invasive measurement if the temperature is going to have clinical import in the patient’s care.
  • Recommended by Jeremy Fried

Neurology
R&R Hot Stuff - Everyone’s going to be talking about thisR&R Hot Stuff - Everyone’s going to be talking about this
Carpenter CR et al. Spontaneous Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis Describing the Diagnostic Accuracy of History, Physical Exam, Imaging, and Lumbar Puncture with an Exploration of Test Thresholds. Acad Emerg Med 2016. PMID: 27306497

  • This is an excellent systematic review and meta-analysis looking at the test characteristics of different components of the history, physical exam and testing in suspected SAH. The critical findings are:
    Neck Pain: (+)LR = 4.1
    Neck Stiffness: (+)LR = 6.6
    NCHCT < 6 hours: (+)LR = 230, (-)LR = 0.01
    NCHCT > 6 hours: (-)LR = 0.07
    Overall, the group concludes that an LP is only useful when the post-NCHCT probability of SAH is > 5% which corresponds to a pre-NCHCT probability of ~ 20%. Basically, high risk patients should have strong consideration for an LP after a negative NCHCT even within 6 hours. For the low-risk patients, perhaps NCHCT is enough.
  • Recommended by Anand Swaminathan

Critical Care
R&R Hot Stuff - Everyone’s going to be talking about this
Quill TE, et al. Discussing treatment preferences with patients who want “everything”. Annals of internal medicine 2009. PMID: 19721022

  • “When asked about setting limits on medical treatment in the face of severe illness, patients and their families often respond that they want “everything.” ” If you struggle with an approach to this common and difficult situation, this article will help you.
  • Recommended by CPN

Emergency Medicine
R&R Hot Stuff - Everyone’s going to be talking about this
Hermann LK, et al. Comparison of frequency of inducible myocardial ischemia in patients presenting to emergency department with typical versus atypical or nonanginal chest pain. Am J Cardiol 2010 PMID: 20494662.

  • Great paper from Mount Sinai in NYC: they analyzed HPIs for all 2500 ED stress tests done from 2004-2008 and found the rate of positives is the same, regardless of whether the patient had “typical” chest pain, “atypical” chest pain, or no chest pain (non-chest pain anginal equivalents). Most useful for convincing the skeptical “well it’s atypical…”
  • Recommended by Seth Trueger

The R&R iconoclastic sneak peek icon key

Research and Reviews The list of contributors R&R in the FASTLANE 009 RR Vault 64 The R&R ARCHIVE
R&R in the FASTLANE Hall of Famer R&R Hall of famer You simply MUST READ this! R&R Hot Stuff 64 R&R Hot stuff! Everyone’s going to be talking about this
R&R in the FASTLANELandmark Paper R&R Landmark paper A paper that made a difference R&R Game Changer 64 R&R Game Changer? Might change your clinical practice
R&R Eureka 64 R&R Eureka! Revolutionary idea or concept R&R in the FASTLANE RR Mona Lisa R&R Mona Lisa Brilliant writing or explanation
R&R in the FASTLANE RR Boffin 64 R&R Boffintastic High quality research R&R in the FASTLANE RR Trash 64 R&R Trash Must read, because it is so wrong!
R&R in the FASTLANE 009 RR WTF 64 R&R WTF! Weird, transcendent or funtabulous!

That’s it for this week…

That should keep you busy for a week at least! Thanks to our wonderful group of editors and contributors Leave a comment below if you have any queries, suggestions, or comments about this week’s R&R in the FASTLANE or if you want to tell us what you think is worth reading.

Last update: Jul 28, 2016 @ 11:12 am

The post Research and Reviews in the Fastlane 144 appeared first on LITFL: Life in the Fast Lane Medical Blog.

EKG Challenge No. 16: Time to Shock or Block?

EKG Challenge No. 16: Time to Shock or Block?

A 76 year-old male with a history of severe ischemic cardiomyopathy with an ejection fraction of 15%, atrial fibrillation on coumadin, coronary artery disease, and chronic kidney disease is brought in by paramedics from a skilled nursing facility with confusion, somnolence, and vomiting. Per EMS report, the patient has been vomiting for two or three days.


On arrival, the patient’s blood pressure is 128/78 with a heart rate of 130 and oxygen saturation of 99% on room air. On exam, he is oriented to self only. He is slightly agitated but following commands. He has some mild garbled speech and is moving all extremities well. He denies chest pain, dyspnea, or abdominal pain. His extremities are well perfused with intact peripheral pulses and preserved capillary refill. A full set of labs are drawn and pending. A head CT is performed and shows an intracranial hemorrhage and small subarachnoid hemorrhage.

 

A routine 12-lead EKG is performed:

Based on this EKG and the patient’s medical history, what are your diagnostic considerations? What should you do next to address the findings on the EKG?

Check back next week for the case conclusion and teaching points!

All bleeding stops — but does idarucizumab (Praxbind) make it stop faster?

PraxBind3.5 out of 5 stars

Persistent life-threatening hemorrhage after administration of idarucizumab. Alhashem HM et al. Am J Emerg Med 2016 June 30 [Epub ahead of print]

Reference

Dabigatran (Pradaxa) is a direct thrombin inhibitor approved for stroke and embolism prophylaxis in patients with non-valve-related atrial fibrillation. When it was first released in 2008, a major disincentive to widespread use was the lack of a reliable reversal agent to treat major bleeds, or to administer before necessary invasive procedures.

In October 2015, the U.S. Food and Drug Administration approved idarucizumab (Praxbind), a monoclonal antibody that avidly binds to dabigatran. under its accelerated approval program. As described by an FDA release, this program:

. . . allowed drugs for serious conditions that filled an unmet medical need to be approved base on a surrogate endpoint.”

In the case of idarucizumab, the surrogate end-points involved normalization of laboratory parameters of anticoagulation. As far as I can determine, there have been no studies that demonstrate convincingly any clinical patient-oriented benefit. In fact, in the major study addressing this issue,  it took a median of 11.4 hours to restore hemostatis after administration of idarucizumab. There was not control group, so we have no idea if this is better than simple watchful waiting. Clearly, it seems far too long to be useful in true life-threatening hemorrhage.

This case report illustrates the point.

A 65-year-old man recently started on dabigatran for atrial fibrillation presented to the emergency department weakness and dyspnea that started approximately 1 hours before. He gave a history of melena for 3 days. On arrival he ws tachycardia (122 ppm) and hypotensive (BP 74/52 mmHg.)

Digital rectal examination confirmed the presence of melena, and a nasogastric tube returned 300 ml bright red blood that did not clear with irrigation. The patient remained unstable despite administration of fluids and packed red blood cells.

The authors note that a markedly elevated thrombin time (120 sec, reference 15-19 sec) indicated significant dabigatran activity. After idarucizumab (5 gm) was administered intravenously. the coagulation tests improved but the patient remained unstable. Upper endoscopy revealed ongoing hemorrhage from a vessel in the duodenum. Several attempts to control the site of bleeding failed, and the patient ultimately underwent angiography with embolization of the gastroduodenal artery. This successfully stopped the bleeding and the patient was discharged after a 4-day hospital stay.

According to Wikipedia, the hospital acquisition cost of a 5 gm dose of idarucizumab is $3500. Although it clearly improves coagulation lab values, it is not clear if if stops significant or life-threatening hemorrhage, or allows for safer procedures such as hemodialysis.

An excellent post at REBEL EM discussed many of the problems with the major study of idarucizumab mentioned above, including industry sponsorship, lack of power, dicey inclusion criteria, and poor study design without blinding or randomization.

Bottom line: idarucizumab had accelerated approval by the FDA as a reversal agent for dabigatran because of biological plausibility. There is still no real proof of its effectiveness. However, in cases of truly life-threatening hemorrhage, many clinicians will no doubt administer the drug if no other treatment options seem available.

Related points:

Case report: hemodialysis for dabigatran overdose

The many potential problems with using dabigatran

Case series: four patients with dabigatran-associated bleeding

Review: the bleeding patient on dabigatram

Dabigatran and the elderly