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 22, 2020

Background: The Surviving Sepsis Campaign published their recommendations for the management of patients with COVID-19 on March 20th, 2020 (though as of the date of this blog post, the document has not been peer reviewed).  36 experts from 12 countries attempted to answer 53 questions that are relevant to the management of COVID-19 patients in the ICU. 54 recommendations were made of which 4 are best practice statements, 9 are strong recommendations, and 35 are weak recommendations.  Finally, no recommendations were provided for 6 of the questions.  The document is divided into 5 sections:
  1. Infection Control
  2. Laboratory Diagnosis and Specimens
  3. Hemodynamic Support
  4. Ventilatory Support
  5. COVID-19 Therapy
Below is the list of recommendations and I will interject my thoughts on the ones that need them.

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.

March 16, 2020

Traditionally, endotracheal intubation has been the gold standard for airway management in cardiac arrest. However, more recent data suggests that maybe less is more (i.e. supraglottic airways and/or bag valve mask ventilation).  The AHA guidelines have also de-emphasized airway management as the old acronym of ABC's has now been changed to CAB's.  In this talk from Rebellion in EM 2019, Dr. Chris Hicks, MD discusses the optimal airway management in OHCA.

March 5, 2020

Welcome back to REBEL Cast, I am your host Salim Rezaie.  In this episode we are going to review a recent focused 2019 update to the American Heart Association (AHA) pediatric advanced life support (PALS) guidelines from 2018-19. This 2019 PALS Update addresses 3 concerns:
  1. Pediatric advanced airway management in pediatric cardiac arrest
  2. Extracorporeal cardiopulmonary resus (ECPR/ECMO) in pediatric cardiac arrest
  3. Pediatric targeted temperature management (TTM) during post-arrest care