EMCrit FOAM Feed

Podcast 63 set off some expected controversy given my take that plain films are a dead imaging modality for c-spine injuries. I wanted to briefly outline my impression of the existing evidence:

Worst Case Scenario for Sensitivity

Mathen R, Inaba K, et al. (J Trauma 2007;62:1427)

Showed a sensitivity of 45% for plain films.

Prospective study of trauma patients who could not be cleared by NEXUS. Got 3-view plain films and CT. Gold standard was evidence of injury during entire hospitalization.

Post NEXUS Prevalence was ~10%, so probably a mix of moderate and high risk patients.

Best Case Scenario for Sensitivity

Mower WR, Hoffman JR, et al. Use of Plain Radiography to Screen for Cervical Spine Injuries (Ann Emerg Med 2001;38(1):1)

It is a reanalysis of the NEXUS Data (NEJM 2000;343(2):94)

818 Patients with 1496 c-spine injuries

Missed 320 and found 498 of the c-spine injuries in those 818 patients

Of the 320 misses, 237 were deemed inadequate plain films

So 498 out of 581 patients with adequate plain films

So sensitivity of the exam is 85%; We'll assume a specificity of 100%

If you evaluate the performance by fracture instead of patient, the numbers become worse

I will say in the Mower paper, they tried to exclude SCIWORA patients, but from what I can glean from this paper (J Trauma 2002;53:1-4), these patients had their MRI without CT scans preceding it. CT may have picked up most of these injuries.

Now how can we get away with such a crappy sensitivity

The reason quoted is the NPV is excellent, they state 99.6% NPV. But NPV is a really crappy number, why...

Because as you change the prevalence, the NPV changes.

So now we need to go to a second enormous study...

Let's look at the Canadian C-Spine Studies (JAMA 2001;286(15):1841 & NEJM 2003;349(26):2510), why? Because their entry criteria are exactly the patients we want to discuss--namely, acute trauma with alert mental status, an injury within the past 48 hours, and in stable condition. The prevalence of c-spine injuries in these patients was ~2% and in the NEXUS trial it was 2.4% So now we have some numbers for a low risk cohort. However, after you get a group of patients who could not be excluded by CCR, the prevalence of the group increases to ~4%. I would argue these patients are now moderate risk. If you pursue plain film strategy in this group, from the best numbers I can gather, you will miss 1 in 100 c-spine injuries and half of these will be clinically significant injuries.

75% of your plain films will be inadequate and require a CT scan

Plain films read as normal but which have loss of lordosis or soft tissue swelling were interpreted as abnormal by NEXUS folks and demand CT scan, this will account for patients going on to CT as well

Finally, patients with persistent midline pain probably deserve a CT prior to d/c in a collar as well

Let's Put it all Together

The authors of this paper from the journal Medical Physics (Med Physics 2009;36(10):4461) attempted to take all the variables: radiation risk, cancer, missed injuries, etc. and evaluate whether plain films or CT is a better strategy. The results...in all risk levels, CT was the smarter move. This was with factoring in the putative cancer risks.

What about MRI for patients with persistent Midline Tenderness

BF asked about this in the comments

(Ann Emerg Med 2011;58:521)

44% of patients with persistent pain had an MRI abnormality

Cervical Spine Injuries in the ED

In this episode, I discuss the diagnosis of c-spine injuries. I argue that we should not send patients to imaging unless we have used the NEXUS rule and then added the Canadian C-spine Rule to the sequence. If we are imaging, it should be with a 3-view reconstructed CT scan. And even after that is done, you still need a clearance exam before removing the collar.

 The Fine Print of the NEXUS rule

You Need to Read Your Footnotes

The folks from Virginia think (J Trauma. 2011 Apr;70(4):829-31. & J Trauma2011;70(4):829-831) Nexus can't be used, but I think if you follow my advice in the podcast, you are probably going to come as close to 100% as a rule can provide. The Canadians also showed less than 100% Sens when using NEXUS (N Engl J Med. 2003 Dec 25;349(26):2510-8), but I would make the same argument--did they really do it the same as the NEXUS study advocates? Do you do it the same? If not, you may be missing injuries.

Then add the Canadian C-Spine Rule if there is Midline Tenderness, but no other NEXUS Criteria

Click on the Image for the Whole Algorithm

Plain Films Suck!

Want the evidence, check out the Spinal Cord Injury chapter at CrashingPatient

Injuries Missed on CT scan

Cervical spine magnetic resonance imaging in alert, neurologically intact trauma patients with persistent midline tenderness and negative computed tomography results. (Ann Emerg Med. 2011 Dec;58(6):521-30)

Computed tomography alone for cervical spine clearance in the unreliable patient--are we there yet? (J Trauma. 2008;64:898 –904.)

Update: this article is hot off of the presses: JAMA Surg. 2014 Sep;149(9):934-9. doi: 10.1001/jamasurg.2014.867. Clinical relevance of magnetic resonance imaging in cervical spine clearance: a prospective study.

Guidelines

Check out the c-spine guidelines from the Eastern Assoc of Surgeons for Trauma (EAST)

And now to the podcast...

EMCrit's favorites from 2011

An Ultrasound Podcast

The Emergency Ultrasound Podcast is some of the best emergency medicine podcasting out there. Matt and Mike have a fabulous teaching style and I can't get enough of their ultrasound education.

A New Blog on EM Evidence

EM Literature of Note provides concise and incisive commentary from Ryan Radecki

EM Posts with Care Pathways and some Ketamine

My friend Reuben Strayer doesn't post often, but when he does, it is pure gold: Emergency Medicine Updates

A Flying Doctor who seems to love Airway

Minh Le Cong is brilliant and I hope he posts on the EMCrit blog as much as he likes.

An Intensive Care Blog with Lectures

The Intensive Care Network is a fantastic blog with lectures, videos, and board preparation resources.

A Surgeon who can communicate--Who would have thunk it?

The Trauma Professionals Blog is the fantastic perspective of a trauma surgeon, Dr. Michael McGonigal.

For more of my favorite things, check out the

Want more Best of?

* Sexy Six for 2014

* Eight is Enough for 2013

* Natural Seven for 2012

* Dirty Dozen from 2010

 

One of the best new podcasts of the year is certainly the Emergency Ultrasound Podcast with Matt Dawson and Mike Mallon. If you haven't checked it out yet, I am replaying their wall motion abnormality talk here on the podcast, because it is so damn good.

If you like it please subscribe to these guys at their website: http://ultrasoundpodcast.com

Here is the handout from the lecture.

Audio only would not be helpful for this lecture.

 

 

Needle vs. Knife Part II

In this podcast, I explain why I don't think needle compression is such a clever idea. Main points are: most people can't find anterior target, most angiocaths won't reach, and if used diagnostically you may not be in the pleura leading to an unidentified pneumo or hemothorax. Also, when used diagnostically, if the chest was negative you just caused a pneumothorax.

If you haven't already, you should listen to Needle vs. Knife Part I with Minh. Also, may of the issues discussed here are also mentioned in the finger thoracostomy episode and the traumatic arrest episode.

Why the standard approach to needle decompression sucks

Normal IV catheters do not reach in up to 65% of the cases

Can J Surg. 2010 Jun;53(3):184-8.

Prehosp Emerg Care. 2009 Jan-Mar;13(1):14-7

J Trauma. 2008 Jan;64(1):111-4

J Trauma 2008 Oct;65(4)":964

Accid Emerg Med 1996;6:426–7

Injury 1996;5:321–2.

Brand New Study state failure in 42% of cases (Radiologic evaluation of alternative sites for needle decompression of tension pneumothorax Arch Surg. 2012 Sep 1;147(9):813-8)

 

Anterior Approach is not Where You Think it is

Emerg Med J 2003;20:383-384

ED Docs got it wrong a lot! (Emerg Med J 2005;22:788)

Use the Lateral Approach if you are going to do Needle Thoracostomy

ANZ J Surg. 2004 Jun;74(6):420-3

Study says Anterior is closer, but (smooth concept here) the patients had their arms in the air

(Acad Emerg Med 2011;18:1022)

Even if you get it right, Cannula may kink, occlude, or compress

Emerg Med J 2002;19:176-177

Traumatic Arrest is not Dismal until Tension Pneumo is Ruled Out

Emerg Med J. 2009 Oct;26(10):738-4

This device makes much more sense to me

Evaluation of ThoraQuik: a new device for the treatment of pneumothorax and pleural effusion (Emerg Med J 2011;28:750-753)

Michelle Lin did a great blog post about the stuff in this podcast on her Academic Life in EM Blog.

Update:

Hot off the press is this swine simulation demonstrating that even when a 14G catheter reached, it may not be sufficient to drain a tension pneumo (Journal of Trauma and Acute Care SurgeryIssue: Volume 73(6), December 2012, p 1410–1415)

A Video Demonstrating Finger Thoracostomy by Cliff Reid

Additional References

Deakin, C., Davies, G., & Wilson, A. (1995) Simple thoracostomy avoids chest drain insertion in prehospital trauma. The Journal of Trauma: Injury, Infection, and Critical Care. 39(2). 373-374.

Masarutti, D., Trillo, G., Berlot, G., Tomasini, A., Bacer, B., D’Orlando, L., Viviani, M., Rinaldi, A., Babuin, A., Burato, L., & Carchietti, E. (2006) Simple thoracostomy in prehospital trauma management is safe and effective: a 2-year experience by helicopter emergency medical crews. European Journal of Emergency Medicine. 13. 276-280

Want a recorded lecture on the topic?

Michael McGonigal had me to his Trauma Conference for this lecture on the finger

Updates

See these observations from the military

I recently spoke at a symposium at the Greater NY Hospital Assoc's with the title: Controversies in Critical Care. I debated Paul Mayo, MD on the topic of whether paralytics should be used for ICU emergent intubations. Of course, I took the pro side of the debate. Dr. Mayo based his con side on an amazing study that came out of his ICU at LIJ hospital in NY.

Here is the abstract of that study:

Seth Koenig, MD; Viera Lakticova, MD*; Abhijeth Hegde, MD; Pierre Kory, MD; Mangala Narasimhan, DO; Peter Doelken, MD and Paul Mayo, MD

The Safety of Emergency Endotracheal Intubation Without the Use of a Paralytic Agent

Here is some literature you may want to cast a more informed vote:

Mort on Complications of Repeated Laryngoscopic Attempts

Here is the article I wrote with Rich Levitan on Preoxygenation for Intubation:

* Weingart, S. Levitan, R. Preoxygenation and Prevention of Desaturation During Emergency Airway Management (In Press, For Review Only)

Update

* Annals ATS. First published online 26 Feb 2015 as DOI: 10.1513/AnnalsATS.201411-517OC Neuromuscular Blockade Improves First Attempt Success for Intubation in the Intensive Care Unit: A Propensity Matched Analysis Jarrod M Mosier , John C Sakles , Uwe Stolz , Cameron D Hypes , Harsharon Chopra , Josh Malo , and John W Bloom    Read More: http://www.atsjournals.org/doi/10.1513/AnnalsATS.201411-517OC#.VPN3bOFGxsk

* BMC Anesthesiol. 2014 Jan 1;14:39

Need an audio only version:

Mp3 of the Paralytic Debate (right click and choose save as)

Now on to the Podcast...

Richard Levitan and I just got our preoxygenation article accepted to Annals of EM. This video describes one of the concepts in the paper.

Email me if you need further explanation.

Here's the Video:

 

Today I am joined by toxicology master, Leon Gussow to discuss a new quasi-legal class of drugs: Bath Salts. I saw my first OD of this a month ago; despite the drug's name, this patient was neither clean nor pleasantly refreshed. He was violent, agitated, and overheated.

This class of drugs are chemically altered hallucinogenic stimulants. Depending on which chemical is used in the salts, the patient can look like they took meth or ecstasy. They will present with a sympathomimetic toxidrome including hyperadrenergic vitals and profound hyperthermia.

How many folks out there have ever used the Bellevue-style metal tub to immerse these patients in ice baths? Let me know in the comments.

Here is a link to Leon's bath salt article in EM News.

This Part II of an interview with Cliff Reid of the amazing blog, resus.me. Cliff is truly a doc after my own heart as you will hear from the cast.

If you haven't already, please listen to Part I of Cliff's interview as well.

He is currently an EMS physician and Director of Training at the New South Wales Ambulance Service.

Cliff's blog, resus.me is an incredible collection of timely articles on emergency medicine, ems, critical care and resuscitation.

Here are some details on what Cliff carries on a mission.

Prehospital Amputation

One of the topics we discuss is prehospital amputation. For more information on this topic, check out the deep-dive page on prehospital amputation.

Come visit me at ACEP and AOCEP Scientific Assemblies.

Now to the Podcast...