Syncope toolkit: Initial assessment of the syncope patient

Initial assessment of the syncope patient

In this section:

History taking

Things to ask the patient (and preferably a witness)

Circumstances or triggers	Medical procedure Stress, pain, fear Ask about situational syncope, for example micturition, defaecation Relationship to exercise Relationship to meals or alcohol.
Posture	Standing, sitting or lying flat
Prodrome	Sweating Feeling hot Palpitations Chest pain Breathlessness Visual and hearing disturbances.
Appearance	Eyes open or closed, pallor, sweating or cyanosis Movement - limb jerking (brief irregular jerky limb movements are common in vasovagal syncope and may be misinterpreted as seizure-like. These movements commence within 10 seconds of loss of consciousness) Tongue biting – typically tip in vasovagal, lateral tongue in epilepsy Injury Duration of episode Unilateral weakness Post-event confusion (more common and prolonged in epilepsy, but can be seen after severe vasovagal syncope).
History of syncope	First event or number and frequency of previous episodes.
Past medical history
Family history	Premature sudden cardiac death at age of under 40 years, inherited heart disease.
Medication

The 3 P’s of vasovagal syncope

The presence of the following features would suggest vasovagal syncope:

Posture – prolonged standing, or similar episodes that have been prevented by lying down
Provoking factors (such as pain or a medical procedure)
Prodromal symptoms (such as sweating or feeling warm/hot before TLoC).

Examination of patient

Cardiovascular examination
Neurological examination if indicated by the history
Other systems as appropriate
Active stand test.

Within a 10-minute consultation, it may be impossible to conduct all aspects of the assessment and it may be necessary, after risk assessment, to arrange a follow-up consultation.

Red flags in syncope

Refer urgently, anyone with transient loss of consciousness (TLoC) who also has any of the following:

ECG abnormality
TLoC during exertion (syncope after stopping exercise is mostly vasovagal)
Family history of sudden cardiac death in people aged younger than 40 years and/or an inherited cardiac condition
Heart failure (history or physical signs)
New or unexplained breathlessness
Undiagnosed heart murmur
Anyone aged older than 65 years who has experienced TLoC without prodromal symptoms
Presence of severe structural heart disease or coronary artery disease
Syncope when supine
Sudden onset palpitation immediately followed by syncope
When preceded by chest pain, abdominal pain or headache
Short prodrome
Unexplained systolic BP below 90 mmHg
Suggestion of gastrointestinal bleed
Bradycardia 40 (awake and in absence of physical fitness).

Referenced from NICE Blackouts guidance 2010 and the 2018 ESC Guidelines for the diagnosis and management of syncope.

Risk stratification tools

Risk stratification tools are of limited value and have not been shown to perform better than good clinical judgement in identifying patients at high risk of serious short-term outcomes. Most risk assessment tools were developed for use in the emergency department and no risk assessment tools have been validated in primary care.

Syncope educational resources for healthcare professionals

Transient loss of consciousness ('blackouts') in over 16s - clinical guideline [CG109], last updated: 01 September 2014
European Society of Cardiology - Guidelines on diagnosis and management of Syncope, 2018
2015 Heart Rhythm Society expert consensus statement on the diagnosis and treatment of Postural tachycardia syndrome, Inappropriate sinus tachycardia, and Vasovagal syncope
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