Dynamic Duo

Heather Darata

Heather Darata


Heather Darata

When Emmanuel Negedu fell to the turf after lifting weights with his teammates and winning a race on the indoor football field in 2009, the 20-year-old’s teammates thought he was pulling a prank.1

But when the 6-foot-7-inch University of Tennessee (USA) basketball player didn’t stand up and laugh, things took a serious turn. Senior Associate Athletic Trainer Chad Newman and Director of Sports Medicine Jason McVeigh converged on the scene to help. Newman was unable to find a pulse and asked someone to bring the AED. McVeigh arrived on scene at the same time as the AED.

The machine was set up. It analyzed Negedu’s heart arrhythmia and shocked his heart back into a normal rhythm. Newman administered CPR until Negedu’s heartbeat and breathing stabilized. Negedu had suffered sudden cardiac arrest caused by ventricular fibrillation.

Negedu was transported to UT Medical Center where he stayed for several days before being discharged.

"It was a big shock," he said. "Still now, I don't believe that happened. But it happened. I feel great now, just like I felt before."

What is sudden cardiac arrest vs. a heart attack?

As its name suggests, sudden cardiac arrest (SCA) happens suddenly and often without any warning. It is triggered by an electrical malfunction in the heart, which causes arrhythmia (irregular heartbeat).2 Since the heart’s pumping action is disrupted, this means that the heart is unable to pump blood to the lungs, brain, and other organs. Within seconds, a person loses consciousness and doesn’t have a pulse. If no treatment is started, a person can die within minutes. More than 320,000 out-of-hospital cardiac arrests occur every year in the United States, and a number of those are from a reversible cardiac arrhythmia known as ventricular fibrillation (V-fib). It’s estimated that about 7,000 children suffer sudden cardiac arrest each year.3

A heart attack, on the other hand, takes place when a blocked artery prevents oxygen-rich blood from reaching a section of the heart.4 Unless the blocked artery is reopened quickly, the part of the heart that receives its nourishment from that artery begins to die. The longer the amount of time passes without treatment, the more damage that occurs. The heart usually keeps beating during a heart attack, unlike during sudden cardiac arrest.

Sudden cardiac arrest and heart attack share a connection. SCA can happen after a heart attack or during recovery. Heart attacks increase the risk for sudden cardiac arrest, but most heart attacks do not lead to sudden cardiac arrest. When sudden cardiac arrest does occur, heart attack can often be the cause. But other heart conditions can also disrupt the heart’s rhythm, which can lead to sudden cardiac arrest. These conditions include heart failure, thickened heart muscle, long Q-T syndrome, and arrhythmias, especially ventricular fibrillation.

What is ventricular fibrillation?

V-fib is a potentially deadly cardiac rhythm disturbance. Instead of beating (contracting) normally, disordered electrical activity makes the ventricles (the heart’s lower chambers) quiver, or fibrillate.5 This stops the heart from pumping blood, which causes collapse and cardiac arrest. V-fib is most commonly caused by damage to the heart muscle during a heart attack. It can also be caused by other heart conditions such as cardiomyopathy (heart muscle disease), congenital heart defects, and in some cases, conditions external to the heart including sepsis (severe body infection), drug toxicity, and electric shock.

What happens for a SCA patient?

Estimates say that more than 95 percent of cardiac arrest victims die before they reach a hospital.6 A victim needs defibrillation to stop V-fib, according to the European Resuscitation Council and the American Heart Association. While V-fib makes up only 18.7 percent of all out-of-hospital cardiac arrests (OHCA) in the United States,7 it is considered a reversible condition when treated immediately with a defibrillator. It is the subject of much attention in emergency medical services (EMS) and emergency dispatch because bystanders can often make a difference before trained responders arrive.

Each minute the brain goes without oxygen, the less likely a patient is to return to a normal life—even if resuscitation happens within 10 minutes.8 After 10 minutes, most resuscitation attempts are unsuccessful. If a patient receives a defibrillation shock within 5 minutes, he or she has a 50 percent survival rate.

Because of the time-sensitive nature, automated external defibrillators (AEDs) have been and continue to be placed in public places such as schools, casinos, airplanes, and passenger trains. This is why: The average call-to-shock time is nine minutes for a “typical community” according to Cardiac Science’s Lives Lost—The Case for AEDs in Your Organization. In a mid-sized urban community, the median response time is 6.6 minutes for EMS. Emergency response may be further delayed in cities during rush hour traffic or with crowded elevators.

Automated external defibrillators

An AED is a portable, lightweight device that delivers an electric shock through the chest to the heart. The shock has the potential to stop an irregular heartbeat and allow for a normal rhythm to begin again after SCA.9

An AED has a built-in computer that checks the heart rhythm through adhesive electrodes applied to the victim’s chest. The computer calculates if defibrillation is needed—a shock is advised only in cases of V-fib or pulseless ventricular tachycardia. When a shock is needed, the AED’s recorded voice tells the bystander to press the shock button on the AED. The shock momentarily stuns the heart and stops the heart’s activity. This gives the heart a chance to resume normal heart rhythm.

AEDs offer a quicker response in a life-threatening situation and allow non-medical personnel to help before EMS arrives on scene.

Pre-Arrival Instruction selection

When a caller reports on Case Entry that the patient is Obviously NOT BREATHING and Unconscious (non-traumatic), the EMD codes the call as a 9-E-1, goes directly to Post-Dispatch Instructions, and provides PDI-a. The EMD has several options now. If the patient is an infant who is less than 30 days old, the EMD will go to Protocol N: Airway/Arrest/Choking (Unconscious) – Newborn/Neonate < 30 Days. If the infant is older than 30 days but younger than one year, the EMD will go to either Protocol A: Airway/Arrest/Choking (Unconscious) – Infant < 1 Yr or Protocol Ya: Tracheostomy (Stoma) Airway/Arrest/Choking (Unconscious) – Infant < 1 Yr.

For patients older than one year, there are four options, depending on age and if the patient has a tracheostomy. For a stoma patient, the EMD will select either Protocol Yb: Tracheostomy (Stoma) Airway/Arrest/Choking (Unconscious) – Child 1–7 Yrs or Protocol Yc: Tracheostomy (Stoma) Airway/Arrest/Choking (Unconscious) – Adult ³ 8 Yrs. More often, the EMD will use Protocol B: Airway/Arrest/Choking (Unconscious) – Child 1–7 Yrs or Protocol C: Airway/Arrest/Choking (Unconscious) – Adult ³ 8 Yrs.

MPDS Protocol Z

Protocol Z: AED Support is used in combination with Protocols B, C, Yb, and Yc. For this CDE, we will be focusing on Protocols B and C.

Panel BC-1 states “If there is a defibrillator (AED) available, send someone to get it now, and tell me when you have it.” In an ideal situation where more than one bystander is present, one person starts CPR and the other person retrieves the AED.

However, if there is only one bystander and an AED is available, the EMD uses Panel Z-3 to direct the bystander to get the defibrillator if INEFFECTIVE BREATHING is present following Panel Z-2, which tells the EMD that the caller should perform BC-1, BC-2, and B-3 (C-3 if directed by the protocol), and then return. For agencies using ProQA®, there are AED progress markers at the top of the screen, reminding the EMD to check whether the AED has arrived on scene so Protocol Z instructions can be continued.

If the person retrieving the AED has not yet returned, the EMD will use Panel Z-3 to direct the bystander on scene to begin CPR (Panel BC-4). When the AED is on scene, the EMD will go to Panel Z-4 and begin AED administration instructions. The EMD should keep in mind Brock’s Law: The presence of an AED does not ensure its use—the EMD does.

The next series of steps are for setting up the AED. EMDs should be aware of the informational panels (T1–6) that offer troubleshooting in the form of additional information and/or questions to ask the caller. Panel Z-5 says “Undo or remove any clothing from her/his chest. If her/his chest is wet (sweaty), dry it off.” T1 Remove Clothing helps clarify this by offering additional information regarding which clothing can be left on and what should be cut or removed.

Panel Z-6 says “Open the lid, if necessary, and press the ‘on’ button, if there is one.” The EMD follows up by asking if the machine is on. If the caller answers no, the EMD can read T2 Machine not on. Once the AED is ready to go, the EMD tells the caller to find the pads and plug them into the machine if necessary. The caller is then directed to peel off the backing of the pads and apply them to the patient’s bare chest. T4 directs the EMD to let the caller know to refer to the picture to clear up any confusion about where they should be placed.

Once the pads have been correctly placed, the machine will give instructions. In Panel Z-9, the blue panel (for the EMD) advises that the most likely sequence is analyze and shock. If there are problems with the analysis portion, then the EMD can troubleshoot on T5. If problems arise with the shock portion, the EMD can ask questions located on T6 to better understand what’s happening on scene. If the AED’s analysis doesn’t find a shockable rhythm or if the analyze/shock cycle is given without results, the AED will advise the caller to perform CPR.

Panel Z-10 tells the EMD to go to BC-4 and have the caller perform CPR for two minutes unless interrupted by the AED. Remember, at this point the voice prompts on the AED device are directing the bystander on what specific steps to take. The EMD fills a supportive role here, encouraging the caller to complete the steps advised by the AED device, and when CPR is advised, using the metronome to set the pace of the compressions for the caller/bystander.

After the two minutes have passed, the EMD should return to Panel Z-10; the machine should reanalyze and may administer a shock before advising more CPR.

If the AED does advise more CPR, go to Panel Z-11 where it tells the EMD to go to Protocol C-9/B-8 and have the caller perform CPR for two minutes unless interrupted by the AED. Once the two minutes of CPR are over, the EMD should return to Panel Z-11. Like Panel Z-10, the AED should then reanalyze and may shock again before advising more CPR. If more CPR is advised, the EMD will give directions from Panel Z-12, which include more CPR from Protocols C-9/B-8 and following the AED’s prompts. The EMD will repeat this panel until help arrives unless the patient begins breathing. In that case, the EMD will continue with Protocol B or C until help arrives.


  1. Edwards D. “Negedu: God Is Going To See Me Through This.” Tennessee Athletics. 2009; Oct. 6. https://utsports.com/news/2009/10/6/Negedu_God_Is_Going_to_See_Me_Through_This_.aspx (accessed March 4, 2019).
  2. “Heart Attack or Sudden Cardiac Arrest: How Are They Different?” American Heart Association. 2015; July 31. https://www.heart.org/en/health-topics/heart-attack/about-heart-attacks/heart-attack-or-sudden-cardiac-arrest-how-are-they-different (accessed March 4, 2019).
  3. “Lives Lost—The Case for AEDs in Your Organization.” Cardiac Science. www.cardiacscience.com (accessed Oct. 16, 2018).
  4. See note 2.
  5. “Ventricular Fibrillation.” American Heart Association. 2016; Sept. 30. https://www.heart.org/en/health-topics/arrhythmia/about-arrhythmia/ventricular-fibrillation (accessed March 4, 2019).
  6. See note 3.
  7. Benjamin EJ, Muntner P, Alonso A, Bittencourt MS, Callaway CW, Carson AP, Chamberlain AM, et al. “Heart Disease and Stroke Statistics—2019 Update: A Report From the American Heart Association.” Circulation. 2019; Jan. 31. https://www.ahajournals.org/doi/10.1161/CIR.0000000000000659 (accessed March 4, 2019).
  8. See note 3.
  9. “What Is an Automated External Defibrillator?” American Heart Association. 2017. https://www.heart.org/-/media/data-import/downloadables/pe-abh-what-is-an-automated-external-defibrillator-ucm_300340.pdf (accessed March 4, 2019).