In our area we have access to many physicians who are willing to present to EMS. One system neurologist is a big supporter of our program and an advocate for improving neurological outcomes from sudden cardiac events. He also consulted as we created our protocol and procedure for inducing TH. He was the perfect presenter to explain the science behind post-cardiac arrest syndrome and how proper care can salvage brain ganglia and neurons both during an arrest and following ROSC.
The neurologist explained the theory of slowing metabolism in a suboptimal environment of high lactic acid, and discussed the potential damage fevers and seizures can bring to the brain in this chilled state and during the rewarming process. This lecture was important because it explained what happens in the intensive care unit after EMS hands off the patient.
Improving cardiac arrest survival takes coordination with at least one tertiary cardiac care center. To address the continuum of care inside the hospital, we recruited the manager of our STEMI and stroke system. Her lecture covered operation of the Arctic Sun temperature management system from the emergency room into the catheterization lab. Since roughly 25% of cardiac arrests are STEMI in origin, this was a good time to emphasize the importance of early recognition in the ROSC patient. She also reviewed how the Arctic Sun stays in place even during the catheterization process. This supported the importance of EMS beginning hypothermia in the field.
In the spirit of being a part of a grander mission in North Carolina, we invited the state RACE CARS manager to present. RACE CARS stands for Regional Approach to Cardiovascular Emergencies-Cardiac Arrest Regional System. RACE is an effort to organize better systems of STEMI care, and it has produced dramatic results. This speaker shared cardiac arrest data from across the state. A key take-away was that the more EMS systems that reported their data, the greater the evidence base to support best practices, and the more they could be embraced to improve outcomes. The data we compiled from our charting clearly had meaning. And, by entering it into the CARES (Cardiac Arrest Registry to Enhance Survival) platform, we could be part of the same thing on a national scale. This topic showed our providers how important our documentation and review of cardiac arrest is and that better patient outcomes could come from evidence-based practice.
The afternoon consisted of four breakout sessions designed to apply the morning’s information: Operational Questions, Inducing Therapeutic Hypothermia, The Pit Crew Process and Dealing With the Living.
The operational session, led by a senior battalion chief, was designed to address questions surrounding logistical demands of the new approach and the issues of conducting resuscitations in public. He discussed the increase in manpower the pit crew model required and how a busy system could have six medical personnel on a cardiac arrest scene for up to 30 minutes.
The American Heart Association now classifies induction of mild hypothermia as a Class IIa intervention, and our session on inducing it was led by two FTOs who explained the clinical management of patients following ROSC. EMS begins the process based on a set protocol that prevents delays in definitive care. Because TH may be harmful if patients are allowed to rewarm prematurely, coordination with our tertiary care hospital is essential. After reviewing different options for initiating TH, our system chose to use a 4ºC saline fluid bolus (30mL/kg, max 2 liters) and application of cold packs to the groin and armpits.
Questions about the new protocol focused on when to initiate the saline and other care required following ROSC, including the rapid acquisition of a 12-lead ECG and aggressive airway management.
For the session on the pit crew process, we introduced and broke down each position. Our process assigns roles to arriving providers as follows:
Arriving first would be ideally three EMTs on an engine. Position 1 is on the patient’s right side; this provider checks pulse and responsiveness, then begins compressions. Position 2 is on the patient’s left side and prepares the AED, including placement of pads around the compressor. Position 3 manages the airway, preparing a King LT (see sidebar) and inserting it without disturbing compressions. Positions change at two-minute intervals to keep the compressor fresh and check the AED rhythm.