April 2017

09:46-17:46

Clinical Question:

• Is IV Olanzapine safe?

Title of Paper:

• A Prospective Observational Study of Patients Receiving Intravenous and Intramuscular Olanzapine in the Emergency Department

Journal and Year:

• Annals of Emergency Medicine, 2016

Lead Author:

• Jon B. Cole

Overview of study methods:

• Prospective, observational study
• ED patients receiving Olanzapine for any clinical indication via either the IV or IM route
• Research nurses observed patients for the 60 minutes (0, 5, 10, 15, 30 and 60 minutes) following administration for the primary outcome of evidence of respiratory depression (multiple criteria)
• They also observed for:
  • OAA/S Scale (5 point sedation scale)
  • Any monitoring data available
  • Any ECG performed
  • Treating physician’s assessment of drug efficacy

Summary of Results:

• 784 patients in final analysis
  • 295 in the IV group
  • 489 in the IM group
• Respiratory depression occurred in 3.7% of the IV group and 2.0% of the IM.
  • 7 patients required intubation – 2 in IV and 5 in IM group
• One episode of Mobitz I and one of bradycardia were observed, both were attributed to other reasonable factors.
• 81% of the IV and 84% of the IM group did not need additional sedation
• Median time in the ED was less for the IV group (386 vs 525 minutes)
• The IV group generally received lower doses (5mg most commonly) than the IM group (10mg most commonly)

Thoughts:

• Prospective, observational data suggesting that IV Olanzapine is pretty safe in comparison to IM.
• The peak onset in probably quicker and than the peak time of 15-45 minutes that you get with IM administration, which may lead to the higher incidence of respiratory depression.
• The need for further sedation within an hour was similar in the IV group with its largely 5mg dose as in the IM group with its largely 10mg dose, so 5mg as an initial IV dose seems reasonable.

Clinical Bottom Line:

• It’s probably safe to use IV olanzapine if you need to, just be aware that there may be a more rapid onset so as is always good with this sort of thing – start low, go slow. As with any sedative drug in the agitated patient, be aware it sometimes doesn’t take much to ‘over-cook’ them if they’ve got lots of other ‘self-delivered’ agents on board so they should be closely monitored.

Other #FOAMed Resources:

• Josh Farkas of emcrit.org includes this paper in a great summary of IV Olanzapine in sedation.

Codes: CC21

Carbon Monoxide

17:46-26:09

CO poisoning is common and there are lots of myths about CO:

1) It can’t pass through walls

CO is a tiny, colourless and odourless molecule that can spread through anything. This means that CO from next door could be the cause of your patient’s symptoms.

2) It only comes from Gas Stoves

CO is produced anywhere where combustion is incomplete. Faulty gas fires used to be common but now it could be wood burners, cold catalytic converters or charcoal BBQs.

3) It causes pathophysiology is like a functional anaemia

CO binds irreversibly to Hb, forming COHb and shifting the oxygen dissociation curve to the left. It also impairs other proteins and binds to platelets so nitric oxicde gets released. There’s some interesting research where dogs were given COHb 70% by breathing gas – they died. They then replaced 2/3 of their blood with poisoned blood and they were fine.

If you think about it from an anaemia point of view, normal Hb 150, an HB 75 is fine. That would be a COHb of 50% – which is near fatal.

4) Everyone Gets Cherry pink mucous membranes

No – bright red blood is a post mortem curiosity. You need COHb levels of 40% to be visible.

5) If your alarm is fine, you’re fine

There was a recent look at fake alarms – so make sure alarms are being bought from a reputable source. Most audible alarms sound at 50 ppm after 60 minutes which is quite a lot. We ideally need <6 ppm over 24 hours. Digital alarms are best.

Think COMA

• Cohabitees – you might not all have a virus at the same time…
• Outside
• Maintained
• Alarm

In low risk patients, who were exposed a while ago, blood tests are unlikely to be helpful. If you do need a level there is no need to do an ABG – a VBG is fine

References and Links

RCEM Learning CO poisoning

Emergency Medicine Ireland

Life in the Fast Lane

26:09-33:43

Clinical Question:

• What is the outcome for poor grade SAH

Title of Paper:

• Outcome after Hunt and Hess Grade V subarachnoid hemorrhage: a comparison of pre-coiling era (1980–1995) versus post-ISAT era (2005–2014)

Journal and Year

• Journal Neurosurgery, 2017

Author

• Konzcalla

Background

• Poor grade SAH can be defined on either H&H or WFNS scoring systems but both imply comatose patients with lots of blood in their brain. Common practice is expectant management rather than aggressive management of the aneurysm.
• H&H grade V is commonly thought to have a 10% survival rate never mind good functional outcomes.
• This group have been treating H&H V with early and aggressive aneurysm treatment for 15 years now and this is their outcome data

Patients studied

• Compared 2 groups
  • Historical data from a chart review (no methods) from H&H V patients in their centre in the 80s when they were conservative
  • Recent data from a prospective database (so much higher quality data) of their current management of SAH
• Looked to see the difference in survival and mRS 0-2 (2 = Slight disability; unable to carry out all previous activities, but able to look after own affairs without assistance)
• They also add some comparisons with data from the decompressive craniectomy and malignant MCA literature

Results

• 50 patients in the early group (8% of all SAH)
  • Intervened on 25% of patients
  • Everyone did badly (mRS 0-2 = 0)
• 200 in the recent group (17% of all SAH)
  • They intervened on the aneurysm in 75% of patients (over half within 12 hrs, half got clipped, half got coiled)
  • A quarter did well (mRS 0-2 = 23%)
• They compare with the DC and malignant MCA data and suggest the H&H V guys do better

Thoughts

• All kinds of issues with the comparisons here (lots of apples and oranges) but the bottom line figure of mRS 0-2 of 23% in H&H V is a take home. Whether or not you can provide this in your centre is a different question but the knee jerk, “extubate and comfort care” is being challenged here
• The therapeutic nihilism is not just the neurosurgeons and we need to lost the tribalism and note we’re all guilty of this
• We also need to be cognisant that although as HCPs we’re often very negative about outcomes resulting in disability that does not mean that our patients feel the same way.

Codes: CC21

Broad Complex Tachys

33:43-42:01

Tachyarrhythmia management is the bread and butter of the Emergency physician

In this new section of the podcast we pick out an RCEMLearning reference section and discuss a small part of it’s content.

This month we pick out broad complex tachycardias (BCT), authored by Elizabeth Docherty and Francis Morris and focus on the section relating to supraventricular tachycardia’s with aberrant conduction.

Being able to differentiate between a true BCT and an SVT with aberrancy is significant both in the acute phase and also longer-term with regards to pharmacology and the need for an ICD.

The reference section itself contains some fantastic notes, so make sure you have a look at them here.

Related Resources:

• RCEMLearning; Broad Complex Tachycardia
• LITFL; VT versus SVT with aberrancy
• Rebel EM; SVT With Aberrancy Versus VT
• Smith’s ECG Blog; Wide Complex Tachycardia:VT or SVT with Aberrancy?

 

Codes: CMP2

Geriatrics

42:01-54:18

There’s an increasing number of geriatrics resources available online and many have them are directly relevant to us. This is by no means a comprehensive list but it’s a good place to get started

• MDTea Podcast
• GEM Podcast
• RCEM Silver Book
• EAST trauma guideline
• HECTOR – Heartlands Manual
• London Trauma Service Geriatric Guidelines

 

Codes: HAP35

54:18-1:01:26

Clinical Question:

• What does the patient’s smile tell you about their chance of having a PE?

Title of Paper:

• Role of physician perception of patient smile on pretest probability assessment for acute pulmonary embolism

Journal and Year:

• EMJ, 2017

Lead Author:

• Jeff Kline

Overview of study methods:

• Patients Studied:
  • anyone undergoing CTPA in two EDs in the states ask to take part.
  • the doc looking after them had to do a structured questionnaire pre CT including a “gestalt” pre test probability and a direct question “did the patient smile”
  • the patient sat in front of a laptop and viewed a series of images and videos while the web camera on it recorded their responses to the images. (of note they have a control video of a cat getting angry and a dog falling in the pool from America’s funniest home movies as a way to make sure the patient did smile at some point)
  • A software programme then “reads” the facial expressions
  • They wanted to know whether the perception of smile affected the pre test probability of disease in either direction

Summary of Results:

• 208 patients, 13% rule in rate
• the doc was more likely to recall a smile the patients who ruled in for PE (63 v40%)
• the software agreed with this (PE positive patients were more likely to demonstrate a happy affect while watching funny cat videos…)

Thoughts:

• this is the second of Kline’s papers looking at this, the first looked at chest pain overall using similar facial recognition software. it found somewhat different results in that patients with less emotional response were more likely to have pathology (though it covered a large range of pathologies not just PE)

Clinical Bottom Line:

• that “gut” feeling you have about patients likely has some validity and emotional response and its perception is part of that. But we’re not yet at a place we can use it clinically.

Other #FOAMed Resources:

• Jeff is on Twitter and a must follow
• Go read the first paper too
• And if you haven’t go read Kahneman too and listen to Gary Klein on EMCrit for the alternative.

Guideline Section 2

1:01:26 – End

Imaging

Use validated decision tools – Ottawa knee in over 2s, Ottawa ankle in over 5s.

Nothing too controversial there. A group to watch out for with Ottawa ankle rules are kids with Tillaux fractures – often Ottawa negative but ankle looks massive. (check out Radiopaedia here for a starter case)

Sometimes you just have to go with your gut and X-ray if you believe something is wrong – this is something you often find you do as the senior doc in the department – learning what the guidelines/rules are is one thing, learning when to go off guidance is another-this is probably where your gestalt kicks in.

The guideline recommends Hot reporting: A report should be available from a radiographer or radiologist before the patient leaves the ED – this happens sometimes at places we work, but not out of hours. What happens at your place? let us know if you’ve managed to implement this!!

NICE talk about MRI as first line test for possible scaphoid fracture. Martin Burns from Edinburgh made a comment and posted a paper he’d been involved with about the potential resource implications of this

Codes: C3AP2A, C3AP2B