Background: Epinephrine(adrenaline) has been used in advanced life support in cardiac arrest since the early 1960s. Despite the routine recommendation for its use, evidence to support administration is less than ideal.  Although it is clear from multiple observational studies that epinephrine improves return of spontaneous circulation (ROSC) and short-term survival, most evidence suggests an absence of improvements in survival with good neurologic outcomes.  In cardiac arrest we want to take advantage of the alpha effects of epinephrine, including peripheral vasoconstriction, and therefore increasing aortic diastolic pressure, which in turn helps augment coronary and cerebral blood flow.  On the other hand, we want to avoid the potentially detrimental beta effects including dysrhythmias, decreased microcirculation, and increased myocardial oxygen demand all of which increase the chances of recurrent cardiac arrest and decreased neurologic recovery.  The only two interventions in cardiac arrest that have shown improve survival with good neurologic outcomes continue to be high-quality CPR and early defibrillation. The debate over the utility of epinephrine in OHCA has been ongoing for several years now and many providers have been awaiting the results of the PARAMEDIC-2 trial that was just published in the NEJM 2018. 

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

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

Background:There is a lack of high quality RCTs  investigating optimal airway management in patients with out-of-hospital cardiac arrest (OHCA).  The majority of evidence comes from observational studies and expert opinion. The observational trials have consistently favored basic airway management (i.e. BVM) over tracheal intubation [3]. Supraglottic airway(SGA) devices offer an alternative advanced airway management technique to endotracheal intubation (ETI) during OHCA. SGA devices may offer an advantage over ETI as they are simpler and faster to placeAdditionally, proficiency  with SGAs requires less training and ongoing practice. Although there have been several recent studies published on airway management in OHCA, this post/podcast will focus on the recently published AIRWAYS-2 trial.

The focus of this talk is on how to cognitively offload our minds as we are running a resuscitation. ACLS provides us with a framework in treating adult victims of Cardiac Arrest (CA) or other cardiopulmonary emergencies. This helps get providers who don't commonly deal with CA, to improve things, such as the quality of CPR, minimizing interruptions during CPR for pulse checks, and the timing/dosing of epinephrine. Emergency Medicine (EM) and the prehospital world are different than many environments in medicine. We get minimal information at the time of patient arrival while at the same time the disease process that is taking place has not quite defined itself.  We are constantly expected to acutely manage and resuscitate anyone who comes in our doors 24-7-365, many times without crucial information. Our job therefore should be to ensure coronary and cerebral perfusion are at their highest quality, but also simultaneously putting the pieces of the puzzle together to figure out why our patient is in CA. It can be very difficult to do both and many times we sacrifice one for the other. It is therefore important to cognitively offload ourselves during the resuscitation of our patients in CA and focus our attention on why they are in CA. As a disclosure for this lecture I did state that some of the recommendations made have evidence to support them and others are more theoretical and certainly up for discussion.
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