March 31, 2020

I have been thinking a lot about patients with COVID-19 and the pulmonary pattern that they develop.  This disease process has been categorized like ARDS, but the reality is it is not like "typical" ARDS.  Lung compliance is often normal in these patients, and many patients are not in respiratory distress despite low O2 saturations.  Patients can have a bizarre hypoxemia that does not correlate with their symptoms.  I have even read reports of patients looking comfortable and speaking in full sentences with oxygen saturations in the 40 – 80% range.  There are also more traditional patients in respiratory distress with similar oxygen saturations.  This is a situation where we cannot treat a patient based solely on a number - pulse oximetry may not be a reliable marker of respiratory compromise.

Approaches to oxygen supplementation have stressed minimizing aerosolization of viral particles by avoiding HFNC and NIV.  This appears to be a fear-based statement as opposed to an evidence based one.  If we go straight from nasal cannula to intubation, we will simply run out of ventilators.  Then, more challenges present themselves like rationing mechanical ventilation and trying to figure out how to split ventilators due to the lack of resources.

Finally, I have yet to find a study that shows a mortality rate <50% once a patient is intubated.  Maybe a better way to deal with these patients is an intermediary step using HFNC or CPAP while proning patients while they are awake, before considering intubation.  In this post, I want to review some evidence to support my thoughts on this and, just assume that in every scenario we are discussing full PPE (eye protection, N95/PAPR, gown, gloves, and face shield).

March 30, 2020

The American Heart Association (AHA) released a focused update in 2019, for advanced cardiovascular life support (ACLS) guidelines, to addend those published in 2017 and 2018 for cardiopulmonary resuscitation (CPR) and emergency cardiovascular care.  These recommendations were based on evidence identified by the 2019 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations (CoSTR) from the International Liaison Committee on Resuscitation (ILCOR).  This ACLS Update addresses three main concerns:
  1. Advanced Airway management
  2. Vasopressors in cardiac arrest
  3. Extracorporeal CPR (ECPR) during cardiac arrest

March 26, 2020

Background Information: Refractory ventricular fibrillation (RVF) is a complication of cardiac arrest defined as ventricular fibrillation (VF) that does not respond to three or more standard defibrillation attempts.1,2 Patients with RVF during their cardiac arrest have a mortality of up to 97%.3,4 Double external defibrillation (DED) involves the use of a second defibrillator providing an additional shock in a sequential or simultaneous manner. The left ventricle (LV), being the most posterior part of the heart and the furthest away from the anterolateral electrode pads, have led some to hypothesize that utilizing an anterior-posterior pad placement (ie. Changing the vector) is what accounts for DED’s success. Some theorize that the increase in amount of energy from two defibrillations as opposed to one is what’s needed to reach the LV. There are also theories suggesting that the sequential administration of the shocks, more effectively lowers the defibrillation threshold of the cardiac myocytes and thus leads to a more successful conversion of VF. In spite of these many theories, the intervention of DED has been studied for decades in the electrophysiology lab and widely discussed in the literature through case reports and meta-reviews. These case reports have shown success and a recent meta-review of 39 patients who received DED showed that 25% of them were discharged neurologically intact with Cerebral Performance Category (CPC) scores of 2 or less indicating normal recovery/mild disability or moderate disability but able to independently perform activities of daily living.5-10 While this literature is promising, DED is a highly variable intervention and there are still many unknown factors which continue to cause debate and controversy. The role of vector direction via pad placement, the role of a pulse interval in energy deliverance and the efficacy in method of delivering DED sequentially vs simultaneously continues to remain unclear. 6-11 The authors of this pilot RCT (DOSE VF) wished to answer some of these questions by first determining the feasibility and safety of performing a full RCT.  In doing so, they used alternate defibrillation strategies such as vector changes and double external sequential defibrillation (DSED) in treating RVF.12

March 25, 2020

Take-Home Points
  1. Before starting a neonatal resuscitation, take some deep breaths to calm yourself
  2. Call in your friends - get a second team to manage the mother, call OB, call the NICU - all hands on deck
  3. Anticipate the equipment you'll need, get it to the bedside and don't forget to turn the warmer on
  4. Assign roles so everyone knows what they're supposed to do
  5. Initiate transfer to a NICU as soon as possible

March 19, 2020

Background: Vasopressors are often used to improve hypotension and perfusion in an effort to decrease mortality of patients with septic shock. Mean arterial pressure (MAP) of >65mmHg has typically been used to guide vasopressor therapy in most patients and higher targets have been recommended for patients with chronic hypertension or coronary artery disease. Results from the Sepsis and Mean Arterial Pressure (SEPSISPAM) [2] and Optimal Vasopressor Titration (OVATION) [3] pilot trials suggested that increased exposure to vasopressors targeting higher MAPs in older patients (≥65mmHg) may be associated with increased risk of death. We now have the 65 trial [1] which is a randomized clinical trial testing the hypothesis that reducing vasopressor exposure through permissive hypotension (Targeting a MAP of 60 – 65mmHg) among patient ≥65 years of age with vasodilatory hypotension versus usual care in the ICU.