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This Post will be updated as new-information arises

 

Hospital Non-Invasive Machines can be Adapted for Invasive Ventilation

Issues:

Most machines are single tube circuits that allow exhalation from a vented mask. If hooked up to an ETT, you need an exhalation port and it must be proximal to a viral filter. Many of the companies sell circuits purpose-built for this, for example:

Respironic's Version

If not, items can be adapted to this use by Respiratory Therapy. Key is anything venting to the environment is filtered

Home BiPAP/CPAP Machines

* Same deal as above

* Sinai's Research Page on Adapting Home CPAP Machines

* Adapting the V60

Back-Up Ventilators

Many chronically vented patients have their primary ventilator and a back-up in their homes. If they want to help, their community, a loan of these back-up ventilators would be helpful.

Oxygen Powered Commercial CPAP Devices

Like the Boussignac device, Pulmodyne Go-PAP,

and similar devices

Intensive Blog's take on NHS Guidance on CPAP

Anesthesia Machines

* APSFASA Anesthesia Machines as ICU Ventilators

Oxylator

See the EMCrit Post

With a PEEP cap in place, these will replace a ventilator

EMCrit CPAP Set-Up

can be used for invasive CPAP through an ETT for patients who are awake and spontaneously breathing freeing up the ICU ventilators for patients requiring mandatory breaths.

see video describing set-up on EMCrit COVID Airway Post

This will not be as comfortable as a legit machine, but it should get the job done

Vortran Garbage Disaster Vents

* Instructional Video

 

Splitting Non-Invasive CPAP

Listen to the Wee below for more on this...

Should work on invasive CPAP as well

Helmet CPAP

* Helmet-Based Ventilation

Splitting Ventilators

This seems absolutely a last resort situation. SCCM has released a guidance document saying the same:

* SCCM Statement on Vent Splitting

* PULMCrit Retort to the SCCM Statement

* Read Jack Iwashyna take on the issue

*

This page will serve as the repository of COVID19 airway management thoughts and recommendations. Each time I post something new, it will exist as a separate post for a week and then be merged into this page.

For the Most Comprehensive Info on COVID19, go to Josh's IBCC Chapter

 

We are at Risk

Inutbations

* El-Boghdadly et al. estimated around 1 in 10 intubations would lead to infection [10.1111/anae.15170]

Non-Rebreather Masks

* First10EM

PPE - What to Wear

* N95 (add a PAPR if available to the N95)

* Surgical Mask over N95

* Goggles that surround eyes with facial contact, face shield, or full joint-replacement-hood with visor (full face coverage desperately preferred)

* Bunny suit, preferably with hood or disposable fluid-proof gown

* Something to cover your neck if not in hood

* If no hooded suit available, disposable cap

* 2 pairs gloves, 1 under sleeves of bunny suit or gown and 1 over, under-layer gloves would ideally be long cuffed

* Booties are a big doffing risk, so wear shoes you can disinfect

Preoxygenation

All of this is based on no evidence (there are no evidence-based strategies out there)

Non-Rebreather

This has been the most recommended strategy in articles/write-ups, but in my mind, it may be the worst of the viable options. To get a decent fiO2, you will need to crank it up to flush rate and I am not sure what effect that will have on the patient’s exhalations becoming aerosolized.

NIPPV

This has been panned for potential to increase risk to providers—however, that is predicated on passive exhalation systems (i.e. vents exhalation goes to the environment and has only 1 tube). However, a 2-tube system is a closed circuit. With the addition of 2 viral filters, this may be acceptable in a negative pressure room. It can also be left on during the apneic period with a jaw thrust. Place on CPAP/PSV, leave the PSV at 0, dial up PEEP only if patient’s saturations do not come up with 100% fiO2.

Critical Note: If you use the vent for preox, you MUST disconnect the vent circuit proximal to the viral filter before removing the mask. Otherwise, COVID will be sprayed all around the room!!!!! See Triple C below.

High-Flow Nasal Cannula

Aerosol risk seems no greater than standard NC and is mitigated by surgical mask (https://ccforum.biomedcentral.com/articles/10.1186/s13054-021-03512-w)

BVM with Viral Filter

* If you don’t have a vent available

* Turn BVM flow up to flush rate, higher flows do not translate to patient end of the bvm

* Place viral filter between BVM stem and mask

* Ideally, a NIPPV mask should still be placed to allow good seal with you away from the patient or just hold two hands on the mask in a thumbs-forward grip

from Safer Airways

* Addition of nasal cannula underneath will allow CPAP with PEEP valve if needed. I would only turn NC up to 4-6 lpm if this used. Often NC fits with no mask leak. More preferable is porting the oxygen through a luer or pressure connection port.

 

Optimal Preoxygenation

The first video uses a nasal cannula, the second avoids the NC leading to even less mask leak:

The Nasal Cannula Video (Next Video avoids using Nasal Cannula)

EMCrit CPAP Set-Up without the NC

Here is a Pict

"Triple C" Circuit Disconnects

May be even higher risk than intubation if you do it wrong

Confer

Preplan with your partner

Clamp

Either non-marring clamp or clamp around 4x4 or tape on ETT (if disconnecting proximal to viral filter, than you can ignore the clamp)

Cut Flow

Put the vent in standby or disconnect the inspiratory limb

EMCrit CPAP Set-Up without the NC

See the Video

Here is a Pict

Here is a Pict with the 22mm OD Male-to-Male Connector and Corrugated Tubing

Better way to use the 3-way Stopcock

I showed in the video that you can use O2 tubing with 3-way stopcock but there is a clean oxygen leak. Bill Murphy, medic extraordinaire, wrote me with a better way. Cut off the fat part of the O2 line. You need to test with your hospital's lines to find out the best place to cut, but once you get rid of protrusion, you can make a tight connection without the multipurpose tube to luer adaptor.

Video Proving that BVM alone doesn't supply enough forward flow

and that even on flush-rate doesn't provide dangerous flow to patient to cause aerosol

Cardiac Arrest

Your safety then their safety

Safer Airway Society Guidelines

By all my SMACC airway buddies

Prepress Version

There is also a link to the article as well as printable infographics at the SaferAirways Site

Now on to the Podcast...

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Michael Patterson FCICM FANZCA

Mike is an intensivist anaesthetist in Melbourne. He has spent years thinking about disasters seen in anaesthetics and ICU--most of them are hemodynamic ones. His original interest in this problem stemmed from the death of a young lady having elective gynae surgery, in the setting of anaphylaxis. She had an easily palpable central pulse and reassuring EtCO2 throughout. He was involved late due to issues with arterial access. She died of a hypoxic brain injury solely because her pressure was too low for too long. He has been reflecting on this over the last few years and building up a picture of the problems and the solutions. Subsequently, he had been involved in one patient that died in the setting of a POCUS pulse but inadequate pressure and another young lady who lived despite nearly the same problem occurring as the lady that died.

Central pulses are almost meaningless

- We are mostly just feeling a change in pressure

- Hence 50/10 might feel similar to 120/80

Central pulses are particularly dangerous in distributive shock where the pulse will be felt strongly below 50/-. This has been my repeated experience. It is easily palpable even in hypovolaemic shock with BP < 60 on occasion - You can’t measure pressure from a central pulse until you place an arterial line

POCUS Pulse as a Representation of Adequate Pulse

The use of POCUS to confirm flow in the femoral artery or palpation of a femoral artery pulse is problematic, as you discussed. In your hands (and proper resuscitationists), there will be an arterial line in place very quickly so it is a non-issue. Obviously, those involved in resuscitation should fix their system to achieve this but for lots of reasons that is a problem in many parts of the world (including most Melbourne ED’s/ICU’s).

The problems with ROSC in the setting of PEA or profound hypotension in general are:

POCUS pulse has the same problems as a central pulse unless applied to the brachial artery where you can place a manual cuff and visualize the occlusion pressure

Normal EtCO2

A normal EtCO2 is not reassuring that the pressure is adequate, as you mention - It is useful to suggest ROSC when it kicks up - It is dangerous as any reassurance in distributive shock where pulmonary perfusion is maintained and EtCO2 often doesn’t drop at all despite BP’s < 50/- - In the cardiac arrest setting, PaCO2 has often risen significantly so an EtCO2 in the 30’s may still represent inadequate perfusion let alone pressure I like your step-wise summary of the progression to ROSC. It is brilliant.

 

The yellow zone is where all the badness is happening in the anaesthetic world and I wonder if that is true in ED and ICU but we just don’t recognize it (as the patients are sick beforehand so any bad outcome isn’t attributed to the haemodynamic management).

You explained the problems with this zone excellently but I wonder if people will appreciate the dangers of a POCUS pulse or a palpable central pulse for that matter. I am concerned they will be misused and prolong periods of hypotension. I know you were only talking PEA but the issues are the same in profound hypotension.

My approach is as follows in the setting of profound hypotension = POCUS pulse:

Radial Pulse?

Identify that the radial pulse is rapidly and easily felt before you have a problem - This is obviously irrelevant for those presenting in cardiac arrest - In most other circumstances, if you knew it was strong and easily palpable prior, you can’t end up with confirmation bias - convincing yourself there is no problem. Occasionally it is difficult to locate prior,

Today I talk with my RACC partner, Brian Wright about the airway management of COVID-19.

Resources

* IBCC on COVID-19

* Peng et al. for Anesthesia

* https://jamanetwork.com/journals/jama/pages/coronavirus-alert

* https://www.esicm.org/resources/coronavirus-public-health-emergency/

* https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance

* https://www.who.int/publications-detail/clinical-management-of-severe-acute-respiratory-infection-when-novel-coronavirus-(ncov)-infection-is-suspected

* https://criticalcarereviews.com/index.php/covid-19

* https://www.nejm.org/coronavirus?query=main_nav_lg

* https://www.cdc.gov/coronavirus/2019-ncov/hcp/index.html

* EM Cases

* Crit Care and Anesthesia Recs

* SARS Packet

Unanswered ?s

* Best PPE

* How to disinfect equipment (e.g. CMAC cart)

Now on to the Wee...

Today on the podcast we discuss High Sensitivity Troponins with Dr. Louise Cullen...

Professor Louise Cullen

Louise Cullen is a Senior Staff Specialist in the Department of Emergency Medicine, Royal Brisbane and Women’s Hospital, and an active clinician-researcher with particular interests in acute cardiac diseases, syncope, and cardiac biomarkers. She is widely published in numerous peer-reviewed journal including the Lancet. Her mantra is that “You do not do research for research sake” and as such, clinical redesign and translational research is a key part of her endeavours.

 COI

Dr. Cullen reports receiving grants from Roche; grants, consultancy fees, and personal fees from Abbott Diagnostics; personal fees from AstraZeneca; and personal fees from Novartis outside of the submitted work.

We have resolved these conflicts by:

1. Not speaking of any individual manufacturer's assays

2. In the US, the manufacturers are eliminating prior assays, thereby obviating the conflict of discussing hsTN (i.e. there will be no purchasing decision on your part--you're getting 'em whether you like it or not)

High Sensitivity Troponins

IFCC has released a lab spec sheet on troponins

Troponin values must be individualized based on your hospital's assay

ACS Decision Aides

* IMPACT Trial

* Comparison of four decision aids for the early diagnosis of acute coronary syndromes in the emergency department

* MDCalc TMACs

* MDCALC EDAC

* HsTNi with decision rules

Other FOAM

* EM Topics

* Hennepin High-Sens Troponin Algorithm

Now on to the Podcast...

 

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This ECPR interview was origianlly published on edecmo.org. The interview was conducted by my buddy, Zack Shinar. I wanted to expose a broader audience to the episode, so I am reposting it here:

ECPR 2.0

The Patient

1. OOH Cardiac Arrest Patients are Different

Cannulation

2. Ultrasound-Guided Percutaneous Placement

3. Wire choices

4. Wire Location Verification

5. Small arterial cannulae

6. Simpler Circuits

Post-Pump Critical Care

7. Find the Injuries

8. Mandatory leg perfusion

9. Lower Anticoagulation Goals

10. Lower Flow Goals

11. Try to avoid venting – Truby et al. PMID:28422817, less is more

12. Understanding Cardiac Prognostication / Stunning

13. Understanding Neuro Prognostication

14. Protection/Ownership

15. In it for the Long Haul

16. Lower Anticoagulation and Hb targets

17. Parade your Successes to every person in the chain

Now on to the Podcast...

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Here is part 2 on midlines.

See Part 1 for the shownotes and introduction. Also, go to part 1 to comment on midline stuff.

Part 1-Primer on Midlines

Now on to the Podcast...

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Today, we discuss a case of a patient who 45 mintues prior to arrival took took 150 Labetalol 100mg and 70 Amlodipine 10mg.

Prior EMCrit Podcast

* EMCrit Podcast - Calcium Channel Blocker Overdose

Hemodynamically Neutral Intubation

* See this EMCrit Podcast

3 Presentations for CCB or BB OD

* Vasodilatory

* Negative-Inotropy (& Chronotropy)

* Combined Picture

Vasopressor-Only Management

For me this is only appropriate for primarily vasodilatory shock (PMID 23642908, Skoog et al., Levine et al.)

Tum-E-Vac Commercial Device for Gastric Lavage

If you believe in lavage...

from manufacturer site

Prior Post on Calcium Channel Blocker OD

* EMCrit Podcast 27

Extrip on CCB

Both dialyzability and clinical data do not support a clinical benefit from ECTRs for CCB poisoning. The EXTRIP workgroup recommends against using extracorporeal methods to enhance the elimination of amlodipine, diltiazem, and verapamil in patients with severe poisoning. [10.1080/15563650.2020.1870123]

Tox & Hound on Mechanism of Insulin

* Insulin for CCB/BB OD

Now on to the Podcast...

[featimage]

Today, we discuss the VEXUS Score. One of the big philosophical mistakes of early EMCrit was my approach to fluids in sepsis. It is no excuse that I was in good company--as in most of the intensivists in the US. I've come to my senses in the past 8 years or so and now I am actively fighting to avoid the drowning of our patients. One of the stalwarts in that fight is my buddy Phillipe Rola. He is an intensivist in Montreal, EMCrit team member, and creator of the Thinking Critical Care Blog.

He, along with Rory Spiegel and Korbin Haycock, has created the VEXUS score to evaluate your patient for fluid overload.

VEXUS Article

VEXUS Article

VEXUS Score

Hepatic Vein

Look at the IVC in the sub-xiphoid

Phased Array Probe may be easiest, but Curvilinear works as well

S wave should be larger than D wave

TR may be a confounder

S just after QRS if you have ECG leads

Portal Vein

Mid-Ax Line on Right Side with probe longitiduinal or R Costal Margin

Use curvilinear

Flow should move towards probe (red)

Normal is continuous flow

If it becomes pulsatile, there is backpressure

If it drops below baseline that is bad

PF <=0.5 (same thing as resistive index)

may be abnormal in pts with low BMI

Renal Artery

Curvilinear with Abd preset

Use color doppler to find vessels

Pick a vessel and look at the PW wave

RRI

0.55-0.7 is normal

Approaches 1 when there is an absence of diastolic flow

IRVF

Look for vein in parenchyma

 

from JACC HF 2016;4(8):683

 

Katie Wiskar Tutorial

Katie's Slide of Confounding Factors

Venous Excess Chapter from Phillipe's Book

venous-congestion-chapter

More from Phillipe on this Topic

* EMCrit Podcast 240- Renal Compartment Syndrome It's all about the Venous Side and We've Been Fracking it up for Years

* Posts on Thinking CC

* Vexus Lite

* VEXUS Mini-Tutorial with Live Vid of a Scan

Literature

* Tang Editorial JACCHF 2016

* VEXUS 2020

Resus Crisis Manual

Now on to the Podcast...