High Flow Nasal Cannula (HFNC) to prevent intubation in COVID patients with respiratory failure?
High Flow Nasal Cannula (HFNC), (set at lowest flow to maintain adequate oxygen starutation), while thought to aerosolize virus particles, are being used in the US in patients with COVID-19 who cannot maintain oxygen saturations ≥90% with a NRB, and are included as weak recommendations in the WHO guidelinesas well as the Surviving Sepsis Guidelines (our quick summary of surviving sepsis guidelines).
Here are some ideas on how to use High Flow Nasal Cannula (i.e. optiflow, airvo, etc) safely, that we’d like community feedback on:
What about using a NRB mask over HFNC AND putting suction on the port you would normally put the 02 tubing? Any virus suctioned out will get trapped in suction bag for disposal.
What about combining a BiPAP Mask, feeding the HFNC through the 02 entry and then adapting the suction from an ordinary vacuum with a HEPA filter to the exhalation port?
We know that BVM can aerosolize virus particles, especially when bagging (which is generally not recommended in the COVID era), however BVM (as reviewed in Episode 140 COVID Part 4 Protected Intubation) is recommended as an option for pre-oxygenation and re-oxygenation after a failed first attempt. A key aspect of the technique to minimize the chances of aerosolization is the type of grip. The “CE” grip is the one handed grip which is not recommended and the “VE” 2-handed grip (with aggressive jaw thrust and the thenar eminences almost touching) is recommended (see image). Note that the majority of the force should up from the fingers directly up towards the provider (as apposed to pushing down with the thumbs)
Left: “CE” one handed grip not recommended. Right” 2 handed “VE” grip with thenar eminences almost touching is recommended for BVM in the protected RSI
Convalescent Plasma for critically ill patients with COVID-19?
In a tiny uncontrolled study in JAMA of only 5 critically ill vented patients with COVID-19 they transfused 400mL of ABO compatible plasma from patients who recovered from COVID-19 and found that at 12-14 days, they had lower SOFA scores, increased PaO2/FiO2 ratio, 3 out of 5 patients were extubated and 4 out 5 patients’ ARDS resolved. Certainly not ready for prime time and further study is needed, but keep your eyes open for further developments. Thanks to FOAMcast for the heads up on this one.
False negative rate of nasopharyngeal swabs
We still have zero reliable information on false-negative rate of nasopharyngeal swabs. We will know once we pair it with serological testing, or have some other comparator. As the prevalence and incidence of disease rises, the negative predictive value of a negative test will decline, so we will be jumping to just treating everyone as COVID+, test + or not.
Best predictors of survival in patients with COVID-19
We are learning increasingly that Case Fatality Rate is impossible to pinpoint, but as the disease rolls through the world, the best predictors of survival are
c) if your healthcare system is overwhelmed or not
Shorter shifts…or at least breaks?
Health care workers can and will catch SARS Co V2 in the community, but the risk is always greater where the viral load is higher and duration of exposure is longer (on shift).
They have the manpower to do this. Many EDs don’t, but perhaps we could up-staff and schedule shift breaks?
Suggested algorithm for triaging patients in the COVID era
From CAEP ED flow in the era of COVID-19
First triage into stay or go
Second triage into respiratory or not
First and second triage are decision points (not separate areas or people); define criteria for discharge ahead of time
Scaleable dirty and clean zones
Clean area must be able to accommodate all levels of care (monitors, lab, procedures), and patients should all be masked
Defined triggers to scale up and down
Care protocols (delegated tasks)
Are young people COVID-19 at risk for severe morbidity/mortality?
CDC data suggests that patients 20-44 years of age are not as immune to significant disease as previously reported and have up to a 20% hospitalization rate and comprise 12% ICU admissions. While mortality increases with age, among adults aged 20–64 years mortality is as high as 20% of hospital admission. However, children aged < 19 years generally have a good prognosis.
Coronavirus disease 2019 (COVID-19) hospitalizations,* intensive care unit (ICU) admissions,† and deaths,§ by age group — United States, February 12– March 16, 2020
End of life care for COVID-19 patients
Infographic from EM Ottawa Blog
Original article from CJEM https://caep.ca/wp-content/uploads/2020/03/EOL-in-COVID19-v5.pdf
Contributors to this COVID update: Daniel Kollek, Laurie Mazurik, Andrew Morris, Anton Helman
This blog post is based on Level C evidence – consensus and expert opinion. Examples of protocols, checklists and algorithms are for educational purposes and require modification for your particular needs as well as approval by your hospital before use in clinical practice.
Dr. Anton Helman is an Emergency Physician at North York General in Toronto. He is an Assistant Professor at the University of Toronto, Division of Emergency Medicine and the Education Innovation Lead at the Schwartz-Reisman Emergency Medicine Instititute. He is the founder, editor-in-chief and host of Emergency Medicine Cases.