May 2018

Clinical Question: Can we clinically predict which patients might benefit from thrombectomy for stroke?

Authors: Andy Neill and Dave McCreary

Codes: HAP 32, HAP26, 

Paper

Stroke vision, aphasia, neglect (VAN) assessment—a novel emergent large vessel occlusion screening tool: pilot study and comparison with current clinical severity indices

www.ncbi.nlm.nih.gov

Author: Teleb, 2017 (Journal NeuroInterventional Surgery)

Background:

There have been a number of studies recently that have suggested a dramatic benefit to thrombectomy for stroke in the subset of patients with a large vessel occlusion. The time windows to do this can be up to 24 hrs. There is no doubt that these patients are the minority of strokes but given the huge number of strokes is there a way we can clinically triage the right patients to the right service? Direct quote – “Effective and efficient prehospital triage of patients with ELVO is now the holy grail of stroke care delivery innovation” They describe at least 10, 4 letter algorithms that have already been studied for pre hospital stroke triage. Despite all this talk of pre hospital this is actually a study of ED triage…

Methods:

– observational data from a single centre (i think). They don’t tell us much about the centre or if the patients were all new presentations locally or transfers from outside hospitals or if they had been triaged to this hospital via EMS

– all their ED nurses were already trained in NIHSS (not even our doctors are…) and they then trained them on this new VAN screen (consisting of lateralising weakness plus one of 1) visual disturbance, 2) aphasia, 3) neglect

Results:

– 62 stroke calls

– 19 were VAN positive (NIHSS was 18 on average for these)

– 14 of these had large vessel occlusion

– they calculate a 90% specificity for their VAN score compared with a 75% specificity for an NIHSS >6  (which isn’t very high) that was previously suggested

– of note all this means that of 62 stroke calls 14 (23%!!) had large vessel occlusion (though they don’t say if they actually intervened on them)

Thoughts

– something like this is important both for pre hospital triage and in the ED as we are in no way equipped with stroke teams or radiology to provide emergent 24/7 CT and CTA for every single stroke patient within 24 hrs of onset

– I don’t think the science here is wonderful as there’s little detail about the population. BUt as many of us are working out our protocols here it’s worth having a look at the things that predict a higher chance of needing thrombectomy

– And lastly don’t expect it to be 23% of your strokes – most studies suggest around 3-4% might be eligible for this. 

Kudos

Swami’s Post on REBEL EM was where I found this

Do you know how and when to undertake a resuscitative thoracotomy in traumatic cardiac arrest?

Authors: Phil Coburn and Becky Maxwell

Codes: HMP2, HMP3, HMP 4

This is the first of a 2 part interview undertaken at the RCEM CPD event in April 2018.  This segment focuses on the management of the Traumatic cardiac arrest secondary to penetrating trauma. 

The talk by the late John Hinds can be found here and some useful videos on resuscitative thoracotomy can be found here. (Bear in mind this video is of a lateral thoractomy and not the ‘clamshell’ as described in the talk.  Please also be mindful of where you are watching the video – the child sitting next to you on the bus probably doesn’t need to watch that!) 

Should we have a geriatrician on the trauma team?  

Authors: Ian Sammy and Charlotte Davies

Codes: HAP 13, HMP3

This interview was recorded at the RCEM CPD event in Cardiff in April 2018.  Ian is an Emergency Physician with global experience, from Salford to Trinidad and via Sheffield for a PhD looking at the outcomes of elderly trauma patients.

The TARN PS tool mentioned in this segment can be found here  

Clinical Question:

Can we use higher D-Dimer thresholds to avoid imaging low-risk patients for PE?

Authors: Dave McCreary and Andy Neill

Codes: HAP8, CAP6

Title of Paper:

Multicentre Evaluation of the YEARS Criteria in Emergency Department Patients Evaluated for Pulmonary Embolism

Journal and Year:

Academic Emergency Medicine. March 2018.

Lead Author:

Christopher Kabrhel

Background:

We like (or seem unable to avoid) investigating for PE in the ED

D-Dimers…?

There has been much debate of late as to whether higher D-Dimer cut-offs can be used for certain patients with low pre-test probability for PE

The YEARS study published in the Lancet 2017 suggested imaging rates could be reduced by 14% by using three questions from the Well’s score (“Does the patient have signs or symptoms of DVT?”, “Does the patient have haemoptysis?”, “Are alternative diagnoses less likely than PE?”), and if all were negative then a D-Dimer threshold of 1000 mg/dL could be used to determine need for further imaging. 

This is an independent validation study of the YEARS criteria in a United States population

Study Design:

Prospective, follow-up study of consecutive ED patients with suspected PE

15 Emergency Departments in the United States

Patients Studied:

Adults presenting to ED with clinical suspicion of PE having objective investigation as such (i.e. had to have minimum D-Dimer testing rather than ruled out at the PERC stage)

Excluded:

High pre-test probability (Wells >6)

Pregnant women

Anti-coagulated

Method:

Treating clinicians provided answers to complete the Well’s score (and therefore the YEARS criteria) as part of initial work up

Non-interventional – patients all underwent standard diagnostic workup for PE (either negative D-dimer of <500 mg/dL or imaging in case of positive D-dimer)

Patients with PE excluded were then followed up for three months

Charts retrospectively analysed:

YEARS criteria – yes/no to the three questions as above

Yes to any = +ve by YEARS criteria and D-dimer <500 required for rule out

No to all three = -ve by YEARS criteria and D-dimer <1000 required to rule out

Outcome:

Proportion of patients who would have been referred for imaging and patients who would have had a missed PE when YEARS criteria applied

Summary of Results:

1789 patients tested for PE

Prevalence of PE 4% on index presentation

Standard workup (Well’s ≤6 & D-dimer <500 = rule out complete):

940 patients (53%) ruled out

2 (0.2%) missed PE

1 on index visit (had CTPA anyway)

1 on follow up (sub-segmental)

With YEARS criteria applied (-ve & D-dimer <1000 or +ve & D-dimer <500 = rule out complete):

982 patients (55%) were YEARS -ve, D-dimer <1000

222 patients (12%) were YEARS +ve, D-dimer <500

Total of 67% patients would have beenruled out without imaging

6 (0.5%) missed PE

5 on index presentation (2 subsegmental)

1 on follow up

14% absolute reduction in imaging with application of YEARS criteria – same as original study with 5% absolute increase in missed PE (2% to 7%).

Clinical Bottom Line:

A reasonable first validation of YEARS but as it’s an observational trial its unlikely that the imaging reduction would be the same in real-life.  I like YEARS as a concept though, so it would be good to see it studied further.

Other Links:

REBELem have a nice summary of the original YEARs study

Ryan Radecki provides this brief summary of this paper on EM Lit of Note 

And then there’s the actual original study, of course

Do you open the chest in blunt trauma?  Do you know the basics well and do you rehearse and deliver the simple interventions quickly and effectively in traumatic arrest?

Authors: Phil Coburn and Becky Maxwell

Codes: HMP2, HMP3, HMP 4

This is the second of a 2 part interview undertaken at the RCEM CPD event in April 2018.  This segment focuses on the management of the traumatic cardiac arrest secondary to blunt trauma and also highlights some controversies in the management of the traumatic cardiac arrest patient. 

How do you make end of life decisions in the trauma bay?  How do you avoid opiate overuse in elderly trauma patients?

Authors: Ian Sammy and Charlotte Davies

Codes: CAP 23, HAP 13, HMP3

This interview was recorded at the RCEM CPD event in Cardiff in April 2018.  Ian is an Emergency Physician with global experience, from Salford to Trinidad and via Sheffield for a PhD looking at the outcomes of elderly trauma patients.

Authors:  Dave McCreary and Andy Neill

Clinical Question

Does a greater occipital nerve block help with the treatment of migraine

Code: HAP 17

Paper

The efficacy of greater occipital nerve block for the treatment of migraine: A systematic review and meta-analysis

www.ncbi.nlm.nih.gov

Author

Zhang, Feb 2018, Clinical Neurology and Neurosurgery

Background

Migraine is weird. No doubt about it. We’re not entirely sure how it works but we do have lots of really good (and often underused) treatments for it. Greater occipiptal nerve block for migraine is probably new to most but was published as part of Ben Friedman’s migraine protocol in an expert opinion piece in annals last year (10.1016/j.annemergmed.2016.06.023). Turns out there is some actual evidence behind it and this SRMA puts it all together. In case you’re wondering how to do it it’s a landmark technique where you find the occipital protruberence and go 2 cm lateral and 2 cm down and robert is your father’s brother

Methods

– Systematic Review Meta Analysis

– Included only RCTs but not neccesarily in ED patients

Results

– 7 RCTs found with 23-72 patients 

– total 320 patients

– in their Jadad score most were considered high quality

– All studies had some kind of sham injection, some compared local and steroid v steroid alone

– When analysed they found the block significantly reduced pain intensity 

Thoughts

– I have been itching to try this for 6 months now but because we have so many other good treatments for migraine (prochlorperazine, metoclopramide, NSAIDs, triptans…) all of my patients have got better before i’ve had a chance to use this!!

– How does it work “The mechanisms of GON block may include the changes in brain nociceptive pathways and the diffuse noxious inhibitory control [32,33]. It is well known that the trigeminocervical complex is connected to the nucleus salivatorius with raphe nucleus, locus coeruleus, and hypothalamus. Painful stimulus of cranial structures is transmitted through trigeminal nerve and superior cervical nerve to the trigeminocervical complex and then upper centers [25,34]. There is important functional connection between the sensory occipital segments and the trigeminal nociceptive system in humans.”

– So hopefully that’s as clear as mud…

Kudos

– The University of Maryland’s EM pearls were the source for this one