May 26, 2025

Good morning,

This month we continue our focus on cardiac arrest care. After staying on scene to provide aggressive resuscitation to the patient, we were able to achieve the return of spontaneous circulation (ROSC) successfully. Great! Today, we will review the steps we should take after we obtain ROSC. 

Post-arrest patients are stay and play 

Once we obtain ROSC, there is often a lot of inertia to immediately extricate and transport. However, the best thing we can do is stay on scene a little longer to continue resuscitation. The reason for this is that we have two major goals for post-arrest patients: 

1. Prevent re-arrest 

2. Prevent further brain injury 

When we get ROSC, we likely have not corrected the underlying reason for the cardiac arrest. This means that the process is still active and can cause the patient to re-arrest. We should look for reversible causes and try and correct these ASAP. In addition, post-arrest patients are often hemodynamically unstable. Drops in blood pressure and oxygen sats can also cause the patient to re-arrest. 

The post-arrest brain often has anoxic brain injury from decreased blood flow during the arrest. Hypotension and hypoxia are each associated with further brain injury in this setting. The more severe and longer the duration of the hypotension and hypoxia, the more severe the brain damage. In addition, when these both occur at the same time, they are synergistic, meaning the total brain injury is worse than the sum of each individually.  

The way that we achieve our main two goals is to immediately get a full set of vitals after obtaining ROSC and aggressively correct any vital sign derangement. In addition, we want to re-check vitals often to make sure we are identifying hypotension and hypoxia as soon as possible. We want to correct hypoxia with hi flow oxygen, use of positive end-expiratory pressure (PEEP) valves, and use of advanced airways. We want to correct hypotension with fluids and push dose epinephrine (PDE). We want to correct arrhythmias with antiarrhythmics and electrical cardioversion. The key is that re-arrest and further brain damage are more likely to occur from unaddressed vital sign abnormalities. If we extricate the patient before doing this, the patient is more likely to be in arrest when we get to the ambulance. 

Use of a post-arrest ROSC check list 

I recommend having a checklist to use as a reminder of all the things we should be doing before extricating post-arrest patients. This checklist should include: 

1. Obtain a full set of vitals: This will address abnormalities (discussed above). 

2. Obtain a 12-lead EKG: This is to look for STEMI since this might guide transport destination. If present, we would want to call the receiving facility to activate their cath lab right away to give them time to mobilize resources. Ideally, we should transmit the EKG and call it in prior to extrication to give them as much time as possible to prepare.

3. Ensure good vascular access: If we only have an IO, we should consider upgrading to an IV for better access. In addition, we should consider placing a second line as a backup since it is easy to lose one during extrication. 

4. Ensure the airway is managed based on the patient’s needs: Some patients will already have an advanced airway. For those that do not, if they are awake enough that they are protecting their own airway, great! For those that are not, we should consider placing one before extrication since it is hard (if not impossible) to adequately bag a patient using a BVM while we are carrying a patient to the rig. If a supraglottic airway is currently in place, consider escalating to an endotracheal tube, especially if the patient is still hypoxic. 

5. Prepare for hypotension: If your patient is not already hypotensive, assume he/she will be soon. Post-arrest patients often receive a dose of epinephrine just before ROSC which is rapidly metabolized out of the blood stream. We can prepare for hypotension by spiking a bag of fluids and mixing a vasopressor. For us that means we will mix PDE if we have not already done so. Given how bad hypotension is, we should assume it is coming and be ready to treat it.

6. Use of antiarrhythmics: This is not routinely needed. It should only be administered if the patient is having large amounts of ventricular ectopy or recurrent episodes of ventricular tachycardia or ventricular fibrillation.  

Once the patient is as stable as possible, then we should proceed with extrication. 

We work very hard for our patients in cardiac arrest. Once we get ROSC, our work is not done! We should continue to provide aggressive EMS care on the scene to decrease the patient’s chance of re-arrest and give them their best chance of a good outcome.  

Be safe and keep up the awesome work!

Jordan Singer, MD

EMS Medical Director, UH EMS Training and Disaster Preparedness Institute

Emergency Physician, UH Cleveland Medical Center

Emergency Physician, UH Elyria Medical Center

Assistant Professor, CWRU School of Medicine

May 19, 2025

Good morning, 

This month, we are focusing on cardiac arrest care. Over the last two weeks, we discussed the two cornerstones of cardiac arrest care: chest compressions and defibrillation. This week, we will focus on where we should be delivering this care.

Cardiac arrest = stay and play

In most medical situations, the sicker the patient, the more we need to do before extrication. Patients don't get sicker than when they are in cardiac arrest. In cardiac arrest, the earlier interventions are performed, the more effective they are. The patient is more likely to respond to defibrillation, return of spontaneous circulation (ROSC) patients are less likely to have devastating brain injury, etc. If we delay these interventions to extricate a patient (even if extrication is short), we are not using interventions when they are most likely to be effective. In addition, the process of extrication takes focus. No matter how good you are at cardiac arrest care, you are better when you are not distracted by extrication. If an advanced life support crew is on scene, the advanced cardiac life support (ACLS) care provided in the field is often the same ACLS care provided in the hospital (some rare exceptions to this). For this reason, the default should be that medical cardiac arrest patients are worked on completely in the field. In EMS, we bring the care to the patient, not the patient to the care. 

Reasons to transport a patient in cardiac arrest or to extricate early

There are some reasons where it would be reasonable to pursue extrication and transport before the ROSC is achieved. These are discussed below:

1. Public arrest: Pronouncing a patient in a very public place is not always the best (i.e., at a large sporting event or in the middle of a supermarket). In these situations, we should still stay and play and work the patient on scene. This gives the patient his/her best chance of a good outcome. However, if we have done all the major interventions and not yet achieved ROSC, we should extricate and transport while still in arrest, since this would not be a venue for field termination of resuscitation.

2. EMS responder safety concern: If we are providing cardiac arrest care and notice that the scene is becoming unsafe, we should immediately extricate the patient. While we should never enter an unsafe scene, sometimes we become aware of safety concerns that were not initially noticed. While it is not optimal for the patient to be extricated before key interventions have been performed, our safety is the priority.

3. Patient meets criteria for extracorporeal membrane oxygenation CPR (ECPR): Some hospitals offer ECPR as a treatment for patients in cardiac arrest who have specific criteria present that indicate they could benefit from this limited intervention. This is a time-sensitive intervention, so patients must be able to be transported to centers that can do ECPR within a very short timeframe. For patients who meet the specific inclusion criteria and can be brought to the ECPR center within the specified time, patients can have fantastic outcomes. This would be a very good reason to prioritize extrication over on-scene care since the hospital would offer a time-sensitive treatment that we cannot offer on-scene.

4. High suspicion for specific causes of cardiac arrest that we cannot treat: This includes arrest from hyperkalemia, pulmonary embolism (PE), pericardial tamponade, and hypothermia. In an arrest from hyperkalemia, patients often need much more calcium than we have on-scene. It would be reasonable to transport this patient to get additional calcium in the hospital. For an arrest from a PE, the patient would need a very strong blood thinner known as tPA, or tissue plasminogen activator, to attempt to break down the clot and achieve ROSC. If the patient arrested from pericardial tamponade, the patient would need a pericardiocentesis, which is not within the scope of practice for EMS. For patients who arrested from hypothermia (not to be mistaken with patients who arrested and then became hypothermic), we often need to perform CPR until the patient is warmed to 32 degrees Celsius, which can take hours. It might not be possible to warm the patient up to this temperature in the field, so transport while in arrest would be indicated. While any of the above COULD be possible, we should only prioritize extrication and transport if we have objective evidence that one of the above is actually likely.

Cardiac arrest patients are as sick and critical as they come. The mainstay of treatment for critically ill medical patients is to resuscitate as soon as possible. This means we bring the care directly to the patient and provide as much cardiac arrest care as possible before extrication.

Be safe and keep up the awesome work!

Jordan Singer, MD

EMS Medical Director, UH EMS Training and Disaster Preparedness Institute

Emergency Physician, UH Cleveland Medical Center

Emergency Physician, UH Elyria Medical Center

Assistant Professor, CWRU School of Medicine

May 12, 2025

Good morning, 

This month, we will be focusing on cardiac arrest care. The two most important aspects of cardiac arrest care are: 1) minimizing pauses in chest compressions and 2) defibrillating early and often if a patient is in a shockable rhythm. While we focused on chest compressions last week, we will concentrate on defibrillation this week.

Why is defibrillation important? 

If the patient is in cardiac arrest due to ventricular tachycardia (VT) or ventricular fibrillation (VF), defibrillation can correct the rhythm, leading to the return of spontaneous circulation (ROSC). Every minute a shock is delayed is associated with a ~10% greater chance of death. Given the importance of defibrillation, we want to shock every opportunity we have. This means we must perform rhythm checks every 2 minutes, so we never miss an opportunity to defibrillate.  

Use anterior-posterior pad placement as the default in cardiac arrest 

We have two options for pad placement: anterior-lateral (AL) and anterior-posterior (AP). Recent evidence supports the AP position having higher odds of ROSC over the AL position. A potential explanation for this is that the vector for the energy is directed more directly through the left ventricle when we defibrillate in the AP position. In addition, many of our patients are obese with large chest walls, so if we use the AL position, the energy might be directed too anteriorly and miss the heart entirely. For this reason, I recommend using the AP position as the default in cardiac arrest. When using the AP position, remember that both pads are placed to the left of the midline. We do not want to place the front pad underneath where we compress and the back pad directly over the spine. Please see the picture below for more details. 

Ways to optimize defibrillation 

We are always looking for ways to enhance how we perform cardiac arrest care. Here are some ways to optimize the process of defibrillation. 

1. Pre-charge the monitor BEFORE pulse/rhythm check. This allows us to shock the patient right after we see that the patient has a shockable rhythm. If we are doing manual CPR, this means we would not need to pause compressions a second time to deliver the shock after charging. If no shock is delivered, the energy will be dissipated automatically (often after the 60s), or the charge can be canceled manually. 

2. Perform compressions while charging the monitor. One of our main goals is to minimize pauses in chest compressions. If we see that the patient is in a shockable rhythm and we have not pre-charged the monitor, we should resume compressions while we charge the monitor and only pause again long enough to deliver the shock. 

3. If using a mechanical CPR (mCPR) device, do not pause compressions to shock. These devices are designed to perform compressions while defibrillations are delivered. For this reason, we should not pause compressions to deliver shocks when these devices are used.

4. Restart compressions immediately after shocking without re-checking pulse/rhythm. We should not delay restarting compressions after a shock to look for a rhythm change or feel for a pulse. The reason for this is it just prolongs the pauses in compressions. Our post-shock pause in compressions should ideally be <1 second if manual CPR and non-existent if mCPR, since we shock through compressions. The first time we re-check a pulse/rhythm after shocking is 2 minutes later at the next planned check. 

5. If the patient remains in VT/VF after 3 cycles of CPR with 3 consecutive shocks, we should consider using either vector change (VC) defibrillation or double sequential external defibrillation (DSED). The recent dose VF trial (Cheskes et al., NEJM 2022) was a randomized, controlled trial that found that DSED and VC each performed better than the standard of care in patients who failed to convert from VT/VF after 3 shocks. VC is where the pad orientation is changed (AP to AL or AL to AP) and only requires one monitor. DSED would require two monitors with two sets of pads attached to the patient (one in AP position and one in AL position). For DSED, both monitors shock in quick succession. These options are allowed in our protocol, and we should consider using these options when our standard shock has failed, since it would be the definition of insanity to keep trying the same thing, hoping for different results. 

Defibrillation is one of the cornerstones of cardiac arrest care. Understanding ways in which this process can be optimized helps us provide the best possible care for our cardiac arrest patients. 

Be safe and keep up the awesome work!

Jordan Singer, MD

EMS Medical Director, UH EMS Training and Disaster Preparedness Institute

Emergency Physician, UH Cleveland Medical Center

Emergency Physician, UH Elyria Medical Center

Assistant Professor, CWRU School of Medicine

May 5, 2025

Good morning, 

This month, we will focus on cardiac arrest care. Our number one goal in the treatment of cardiac arrest is for the patient to have a neurologically intact recovery. Our brain is everything we are, and we must preserve the brain to have the patients walk out of the hospital. There are two ways that we can achieve this goal: by minimizing pauses in chest compressions and by ensuring high-quality post-arrest care. Today, we will review why minimizing compressions is so critical and discuss ways we can minimize pauses.  

Why are pauses in compressions harmful? 

The purpose of chest compressions is to circulate blood to deliver oxygen to vital organs. The most important organs we are trying to preserve are the heart and brain. It takes time to build arterial pressure with this pressure dropping rapidly with even a few seconds of pause. For this reason, any pause in compressions (even if only for a few seconds) can be harmful to the brain and heart. It is also important to remember that the damage is cumulative. Therefore, even short pauses can add up to significant injury if there are enough of them. 

The impact of compression pauses on the heart 

We know that outcomes are often better for patients in a shockable rhythm because it is something that we can rapidly correct. However, without chest compressions, the heart is less likely to respond to a shock. In addition, if the pause in compressions is long enough, the rhythm might degenerate to a non-shockable rhythm. The picture below shows a potential scenario where a patient was in a shockable rhythm at the time of the initial call to 911. The patient did not receive bystander CPR, and by the time EMS arrived, the patient was no longer in a shockable rhythm. 

The impact of compression pauses on the brain 

Brain damage from lack of oxygen is irreversible. After four minutes without oxygen, the brain begins to be injured. After 5 minutes, brain cells die rapidly. If enough brain injury occurs, the patient might never wake up or be independent, even if we can get the heart beating again.  

If pauses in compressions are so bad, why do we pause every two minutes (or at all)? 

While chest compressions are critical, defibrillation for a shockable rhythm is equally important. This is because every minute a shock is delayed, it is associated with a ~10% greater chance of death. We need to balance shocking as early and often as possible with wanting to minimize compression pauses.  

What are ways that we can minimize pauses in compressions? 

1. Bystander CPR: This is debatably the single most important aspect of out-of-hospital cardiac arrest care. If this is not present, most of the damage might have already occurred prior to EMS arrival on the scene. Emergency medical dispatchers play a pivotal role if they can identify cardiac arrest over the phone and get the caller (or another bystander) to perform chest compressions, which can absolutely save a life. While many in EMS are not directly involved in dispatch, we still play an important role in bystander CPR. This is because local leaders lean on fire and EMS for expertise in prehospital care. We should use this as an opportunity to promote policies that can increase rates of bystander CPR. 

2. Do not pause compressions for placing advanced airways: if unable to place an endotracheal tube through compressions (which is not easy), place a supraglottic airway. 

3. Practice placing a mechanical CPR device in under 10 seconds. 

4. Pre-charge the monitor: this allows us to shock the patient the moment we confirm that the patient has a shockable rhythm. If we have not pre-charged the monitor, we should continue compressions while the monitor is charging and only pause to deliver the shock if doing manual CPR. As a reminder, we can defibrillate patients while mechanical CPR devices are running and should not pause them to shock. 

Understanding why pauses in compressions are so harmful helps us understand our specific priorities in cardiac arrest care. We should always focus on ways to further minimize pauses in compressions to achieve the best possible outcomes for our patients. 

Be safe and keep up the awesome work!

Jordan Singer, MD

EMS Medical Director, UH EMS Training and Disaster Preparedness Institute

Emergency Physician, UH Cleveland Medical Center

Emergency Physician, UH Elyria Medical Center

Assistant Professor, CWRU School of Medicine