Picture the scene…
You are working in the ED. The next patient is sitting up in bed and looks well, and as you introduce yourself he says “Nothing to worry about Doc, I just fainted. Can I go home?…”
To learn about the management of the patient with syncope.
Task 1 – Read
Read this short induction blog post from RCEM Learning1.
Task 2 – Listen
Task 3 – Discuss
This part of the teaching session should be lead by an experienced clinician. The cases provided are merely examples and if possible the learners should be encouraged to discuss patients they have seen in their clinical practice.
Case 1 – A elderly patient who’s fallen
An 80 year old attends the ED with facial injuries, telling you she tripped over the cat.
1, What in her brief history already makes you suspicious about this patient’s “fall”?
Generally when fall over (and don’t lose consiousness) we are able to put out our hands to save us. Occasionally this isn’t possible – if you are carrying shopping for example, but you should specifically ask exactly what the patient was doing when they “fell”.
2, What features are you especially looking for on examination?
We need to make sure this patient hasn’t had a cardiac cause for her syncope. Listen particularly to her heart for the murmur of aortic stenosis and feel her pulse for its rate and rhythm. You also need to look carefully at her ECG.
3, What does her ECG show? And what would you do next?
Her ECG shows “trifasicular block3“.
Trifascicular block (TFB) refers to the presence of conducting disease in all three fascicles:
- Right bundle branch (RBB)
- Left anterior fascicle (LAF)
- Left posterior fascicle (LPF)
In this case the patient’s heart’s electrical system is really struggling and she may have had an asystolic pause during her collapse.
4, What next?
The patient should be referred to the cardiology team for further management. They may decide to offer her a pacemaker or perform further monitoring.
Case 2 – A young patient with a blackout during exercise
A 35 year old woman presents a collapse whilst playing football.
1, Why is this presentation particularly concerning?
During exercise the body is doing all it can to increases oxygen delivery to the tissues: the heart rate increases and the stroke volume increases, both increasing the blood pressure and cerebral perfusion pressure. A syncopal epsiode is a drop in cerebral perfusion pressure – the exact opposite of this physiological effect, so something pretty bad must be happening!
2, What questions are particularly important when taking the history?
In a young person with syncope we need to focus on the potential cardiac causes. Thinking about the physiology, this could be due to a tachyarrthymia (and a drop in stroke volume), which may cause palpitations prior to the collapse. These conditions may be inherited so a history of sudden cardiac death in first degree relatives would be incredibly concerning. Also ask about previous history of “faints and funny turns” that maybe haven’t ended up in the ED4.
This is the patient’s ECG…
3, What does this ECG show?
This ECG shows voltage criteria for left ventricular hypertrophy with deep lateral Q waves. This would fit with the patient having Hypertrophic Obstructive Cardiomyopathy5.
4, What would you do next?
This patient should be referred to the cardiology team. She needs an echocardiogram to look for septal hypertrophy, and if this is normal a Cardiac MRI. She may need an implantable defibrillator and advice about further exercise.
Task 4 – Summary
In this session we have learned about the clinical assessment of the patient with syncope and thought about the features in the history, examination and ECG that help differentiate between the potential causes.
A transient loss of consiousness is an important presenting complaint to consider carefully, after all if the cause isn’t diagnosed it may progress to a non-transient loss of consiousness (which is called coma or death!).
Consider these questions based on your learning today
1, What are the three physiological variables that make up cerebral perfusion pressure?
Cerebral perfusion pressure is proportional to heart rate x stroke volume x total peripheral resistance, so a reduction in one or more of these may cause a drop in “global cerebral perfusion” and a transient loss of consiousness
2, What are the “three Ps” that make an uncomplicated “faint” a more likely cause?
1, Prodrome – sweating or a feeling of warmth with pallor before the syncope.
2, Provoking factors – something that has caused a vagal stimulus: pain, fear, or perhaps coughing or micturition
3, Posture – prolonged standing, or an episode is [revented by lying down.
NOTE – Palpitations is not one of the Ps!
Task 5 – Reflect
In order to embed today’s learning further, reflect on what you have learnt and record in your portfolio whether it has had any impact (or is expected to have any impact) on your performance and practice.
Was this a topic that you were confident you knew already? Which parts were new to you? Were there elements that you will use on your next clinical shift.
Dscuss this session with your colleagues – were there people who missed it who you can share the highlights with?
References and Further Reading
- 1.Minns T. Induction – TLoC. RCEM Learning. Published February 8, 2018. Accessed June 6, 2020. https://www.rcemlearning.co.uk/foamed/induction-tloc/
- 2.May N. Syncope at St Emlyn’s. St Emlyns. Published August 22, 2014. Accessed June 6, 2020. https://www.stemlynsblog.org/induction-syncope/
- 3.Burns E. Home | ECG Library | Trifascicular Block Trifascicular Block. Life in the Fast Lane. Published April 30, 2019. Accessed May 28, 2020. https://litfl.com/trifascicular-block-ecg-library/
- 4.Albassam OT, Redelmeier RJ, Shadowitz S, Husain AM, Simel D, Etchells EE. Did This Patient Have Cardiac Syncope? JAMA. Published online June 25, 2019:2448. doi:10.1001/jama.2019.8001
- 5.Burns E. Hypertrophic Cardiomyopathy (HCM). Life in the Fast Lane. Published March 16, 2019. Accessed June 6, 2020. https://litfl.com/hypertrophic-cardiomyopathy-hcm-ecg-library/