What does Cardiac Arrest look like?

The classic understanding of Cardiac Arrest is someone who is dead.

The initial picture would be one of someone not breathing, lying motionless on the floor.

But this is not strictly true, certainly in the first few minutes of cardiac arrest. 40% of casualties who experience cardiac arrest will display agonal breathing - an abnormal breathing pattern, often audible, characterized by deep, laboured, irregular gasps. (1) As such the 2010 UK and ERC Guidelines changed the recognition of cardiac arrest from “unconscious and not breathing” to “unconscious and not breathing normally”.

The 2015 update includes the additional advice that bystanders and emergency medical dispatchers should be suspicious of cardiac arrest in any patient presenting with seizures (2-4) and carefully assess whether the victim is breathing normally.  Although the pathophysiology is not fully understood, seizures can be a result of cerebral hypoxia and is relatively common in nearly 30% of cases (5).

So now, our view of ‘dead’ following cardiac arrest is a casualty of may be breathing, albeit abnormally, and possibly moving.

Consider these examples of casualties experiencing cardiac arrest.

Chris Solomon

Caught on camera while filming the BBC series Helicopter Heroes, Chris Solomon began to experience a serious heart attack, presenting as significant chest pain. The paramedics perform their assessment and make a plan of action.

At 2.19 of the video, one of the Paramedics states “He’s in VF, get him on the floor”. At this point Solomons is in Cardia Arrest. Shortly after being brought to the floor they begin CPR and at 2:35 he begins to seize; his right arm extends rigidly and lifts up followed by his left arm.

We typically imagine a ‘dead’ person as laying motionless or limp but this video perfectly demonstrates muscle tone and involuntary movement in the casualty.

Bondi Beach I

A 54 year old male, experiencing chest pain on the beach. There are again some more learning points here:

  • It is established right at the beginning that laying on his front is the most comfortable position for the casualty but at 0:20 they roll him onto his back. Leave the casualty in the position they feel most comfortable.

  • At 0:20 they also apply the defibrillator, whilst he is fully alert. Please don’t do that.

The casualty arrests around 1:30 and you can - albeit very briefly at 1:40 his left arm is outstretched and rigid. Excellent CPR is then performed.

Howard Abravanel

Initially believed to be a seizure, Abranavel collapsed following a game of basketball. Described by an eyewitness as “shaking, and we started seeing foam coming out of his mouth”. At 1:40 Abravanel is seen laying on the floor moving, almost rest while experiencing cardiac arrest. At 2:12 whilst being assessed by an of-duty Doctor, you can notice abdominal movements, congruent with the use of accessory muscles in agonal breathing, You also get to see some rather special CPR here.

Danny Atkinson

Cut straight to 1:20 here. Paramedics attend a classic case of heart attack. They start by asking pertinent questions but at 1:56, Atkinson is asked to “Stand up for me, turn right around and have a seat again”. Stress and exertion are both triggers to heart attack. Don’t ask anyone experiencing chest pain to do this.

At 2:00 the casualty appears to be convulsing followed by deep, audible - almost snoring - breaths. The Paramedic asks “Does he have a history of seizures?”

Bondi Beach II - Takahiro Ono

Skip to 0:55. Takahiro Ono is pulled unconscious from the water. Despite this case being cardiac arrest as a result of drowning rather than heart attack as seen in the previous videos, the pathophysiology of cerebral hypoxia is the same.

Throughout this video you clearly see agonal breathing and spasmodic movements, especially around 2:19, 2:30, 2:50 and 3:30.

Hank Gathers

On 4th March 1990 Hank Gathers collapsed on the court during an American College League match aged only 23 years old. In this video you see Gathers drop to the floor at 0:36, attempts to get up and then experience a significant seizure at 0:58.

On the assumption that this was an epileptic seizure the onlookers did exactly the right thing in leaving the casualty alone to continue the seizure, however, it was not an epileptic seizure, Gathers had suffered Sudden Cardiac Arrest. Only 3 months previously Gathers had collapsed during a game and was subsequently diagnosed with a heart condition and placed on medication.


Seizure vs Cardiac Arrest?

For agonal breathing the protocols are clear - any casualty who is unconscious and not breathing normally should be assumed to be in cardiac arrest and CPR should be started as soon as a defibrillator is summoned.

But how do we distinguish a hypoxic seizure following cardiac arrest from an epileptic seizure?

Scenario 1:

Your colleague, a slight 26 year old female with no medical conditions which she has disclosed you you or your colleagues, has been working extremely hard on a long term project which is coming up to deadline. You are aware that she, and the whole team, have been putting in extra hours in the office and at home to complete the project. She is also committed to her training and as usual, she wheels her bike into to the office, still in her cycling gear on a particularly warm august morning. As she enters you notice that her email account was active until 4am and with it being 8:30am now we can assume she has had little to no sleep.

Your colleague collapses on the floor and begins to convulse face down. Because of her agitated movements and positioning it is difficult to assess her breathing accurately. You are confident that she is breathing but not sure if her breathing is normal.

Seizure or cardiac arrest?

Scenario 2

Your colleague, a 50 year old male who is overweight and a known smoker has been manually handling equipment upstairs as the lifts are not working. As he drops off the final package he drops to the floor and begins to convulse.

Because of his agitated movements and positioning it is difficult to assess his breathing accurately. You are confident that he is breathing but not sure if his breathing is normal.

Seizure or cardiac arrest?

It is likely the casualty in Scenario 1 is experiencing a seizure possibly brought on by epilepsy which she has not disclosed or by a combination of environmental, physical and psychological stressors. It is unlikely that she has experienced sudden cardiac arrest as she does not fit the demographic; young, female and athletic. A defibrillator should be summoned for anyone who has collapsed and - if it is assumed to be her first seizure - a plan to transfer this casualty to hospital should be considered. But she probably does not need CPR and Defibrillation yet, rather the standard management plan for seizures.

Further Reading: Epilepsy

It is likely the casualty in Scenario 2 is in cardiac arrest given the history of exertion and the demographics; male, overweight and a known smoker. This casualty requires immediate defibrillation and good quality CPR whilst an Ambulance is called.

Using this approach you will not always get it right - take the example of Hank Gathers above, a 23 year old athlete who does not fit the demographic or, more famously, Fabrice Muamba, who collapsed on a football pitch on 17 March 2012, also a professional athlete aged 23. Or Christian Eriksen, a Danish football player, suffered a cardiac arrest while playing in a European Championship match in 2021 aged 29. But these exceptions are notable because they are exceptions.

Looking at the casualty, you will make a better decision on whether they should be left to recover or to begin resuscitation rather than being based simply on whether they are in seizure or not. But if something just doesn’t feel right, always maintain that suspicion of Cardiac Arrest even in cases where the casualty is known to have epilepsy (6, 7).

Casualty History

If you have been with the casualty for some period before - a colleague, close friend or family member - this is easier than attempting to collect a history at the scene from the casualty but a history may be obtained from their colleagues, friends or family members.

It is very likely that the casualty has preexisting cardiac or respiratory disease (81.5%) and experienced warning symptoms before the event (51-91.4%), typically chest pain and dyspnea. In most symptomatic patients (93%), symptoms recurred within the 24 hours preceding Sudden Cardiac Arrest (8, 9).

References

  1. Clark JJ. Larsen MP. Culley LL. Graves JR. Eisenberg MS. (1992). "Incidence of agonal respirations in sudden cardiac arrest". Annals of Emergency Medicine. 21 (12): 1464–1467.

  2. Perkins GD, Handley AJ, Koster RW, Castrén M, Smyth MA, et al (2015) “European Resuscitation Council Guidelines for Resuscitation 2015 Section 2. Adult basic life support and automated external defibrillation”. Resuscitation. 95. 81-88

  3. Breckwoldt J, Schloesser S, Arntz HR. (2009) “Perceptions of collapse and assessment of cardiac arrest by bystanders of out-of-hospital cardiac arrest (OOHCA)”. Resuscitation 2009;80:1108–13.52.

  4. Stecker EC, Reinier K, Uy-Evanado A, et al. (013) “Relationship between seizure episode and sudden cardiac arrest in patients with epilepsy: a community-based study. Circulation: Arrhythmia and Electrophysiology. 6:912–6.

  5. Lybeck A, Friberg H, Aneman A, Hassager C, Horn J, Kjærgaard J, Kuiper M, Nielsen N, Ullén S, Wise MP, Westhall E, Cronberg T (2017) “TTM-trial Investigators. Prognostic significance of clinical seizures after cardiac arrest and target temperature management”. Resuscitation. 114:146-151.

  6. Nurmi J, Pettila V, Biber B, Kuisma M, Komulainen R, Castren M. (2006) “Effect of protocol compliance to cardiac arrest identification by emergency medical dispatchers”. Resuscitation. 70:463–9.62

  7. Clawson J, Olola C, Heward A, Patterson B. (2007) “Cardiac arrest predictability in seizure patients based on emergency medical dispatcher identification of previous seizure or epilepsy history”. Resuscitation. 75:298–304.

  8. De Maio VJ, Stiell IG, Wells GA, Spaite DW (2000) "Cardiac arrest witnessed by emergency medical services personnel: descriptive epidemiology, prodromal symptoms, and predictors of survival". Annals of Emergency Medicine. 35(2). 138-146.

  9. Marijon E, Uy-Evanado A, Dumas F, Karam N, Reinier K, Teodorescu C, Narayanan K, Gunson K, Jui J, Jouven X, and Chugh SS (2016) “Warning Symptoms Are Associated With Survival From Sudden Cardiac Arrest “. Annals of Internal Medicine. 164:1, 23-29