Hypothermia was first introduced in 2002 by two studies, Bernard et al and The Hypothermia After Cardiac Arrest (HACA) trial.1,2 The latter, although a small trial, showed improved neurologic outcomes at six months when patients were cooled to 32-34oC. For a long time, a temperature of 33oC was the widely accepted standard of therapy for out-of-hospital cardiac arrest.1 In recent years, a trial aptly named the Targeted Temperature Management (TTM) Trial challenged this notion,3 finding that a temperature of 33oC did not confer any benefit over 36oC.4 Since then, not only has the overall benefit of the therapy remained in question, but many institutions were also left on their own to decide the most appropriate temperature to target. Fever has been proposed as a risk factor for unfavorable outcomes, but the available data only gives us association, not causation. The authors of the TTM trial have now come out with their subsequent study looking to assess the benefit of avoiding fever versus targeting a specific temperature in critically ill patients following cardiac arrest.
Background: Head up (HUP) CPR is an emerging concept. The theory behind HUP is it allows for venous blood to drain from the brain to the heart thereby decreasing intracranial pressure and lowering the arterial/venous pressure waves which concuss the brain with each compression. Additionally, conventional CPR increases vascular pressure in both the venous and arterial sides of the heart simultaneously which in turn increases intrathoracic and intracranial pressure which can impede cerebral blood flow and compromise coronary circulation. All of these theories were evaluated and confirmed in animal models with very limited human trials.
In order for HUP to work however, we have to be able to effectively pump blood up to the brain which is not typically achieved with conventional CPR (C-CPR). Active Compression Decompression with Impedance Threshold Devices (ACD-ITD) are one way to improve C-CPR. They can theoretically help by reducing intracranial pressure (ICP), reduce the potential for concussion with every compression, increase cerebral perfusion pressure (CerPP) and coronary perfusion pressure (CorPP). However, with any new approach, we should always temper enthusiasm, as the realities of implementing them may actually not be helpful, and maybe even harmful....Read More
Background: A major challenge during the COVID pandemic is balancing personal protection and communication. Being heard while wearing a surgical mask or N95 isn't too much of a challenge, communication can be significantly impaired while wearing a respirator mask. There are a number of fixes to this problem. Here, we share one simple, inexpensive option via Whit Fisher, MD (https://www.procedurettes.com/)...Read More
Background: Despite medical advances, survival after out of hospital cardiac arrest (OHCA) is still largely dependent on high-quality CPR. Many of these events are due to a primary cardiac event, likely coronary artery occlusion. Current guidelines recommend reperfusion therapy following cardiac arrest with signs of acute coronary occlusion on EKG. But this only applies when return of spontaneous circulation (ROSC) is achieved. What about those in refractory arrest? Is there a way to increase survival in those patients? Keeping in mind that achieving ROSC may be impossible without reperfusion and reperfusion will likely not occur without ROSC....Read More