Syncope

Question 1

Transient loss of consciousness

Answer 1

A state of real or apparent loss of consciousness with loss of awareness, characterised by amnesia for the period of unconsciousness, loss of motor control, loss of responsiveness and a short duration

Question 2

Things that transient loss of consciousness can result from

Answer 2

Head trauma, syncope, epileptic seizure, transient loss of consciousness mimics

Question 3

Syncope

Answer 3

Transient loss of consciousness due to cerebral hypoperfusion, characterised by rapid onset, short duration and spontaneous complete recovery

Question 4

3 categories of syncope

Answer 4

Reflex syncope, orthostatic syncope, cardiac syncope

Question 5

Reflex syncope

Answer 5

All types of syncope in which neural reflexes modify heart rate and/or vascular tone hence predisposing to a fall in MAP of sufficient severity to affect cerebral perfusion causing a transient period of cerebral hypoperfusion resulting in syncope or near syncope

Question 6

What type of stimulation causes cardioinhibition in reflex syncope?

Answer 6

Vagal stimulation

Question 7

When the pathway of reflex syncope is activated, what causes vasodepression?

Answer 7

Depression of sympathetic activity to blood vessels

Question 8

3 types of reflex syncope

Answer 8

Vasovagal syncope, situational syncope, carotid sinus syncope

Question 9

Most common type of syncope

Answer 9

Vasovagal syncope

Question 10

In vasovagal syncope, what is faint triggered by?

Answer 10

Emotional distress (e.g. pain, fear, phobia) or orthostatic stress

Question 11

Typical prodrome of vasovagal syncope

Answer 11

Pallor, sweating, nausea

Question 12

Main risk in vasovagal syncope

Answer 12

Risk of injury when falling

Question 13

How can vasovagal syncope be averted?

Answer 13

By adopting horizontal gravity neutralisation or leg crossing to increase venous return

Question 14

Treatment for vasovagal syncope

Answer 14

Education, reassurance, avoidance of triggers (if possible), adequate hydration

Question 15

In situational syncope, what causes faint?

Answer 15

Faint during or immediately after a specific trigger e.g. cough, micturition, swallowing etc

Question 16

Treatment for situational syncope

Answer 16

Treat the cause if possible (e.g. cough), advise patient to lie down if possible (e.g. during coughing episode), avoid dehydration and excessive alcohol, cardiac permanent pacing may be needed in some cases of situational syncope

Question 17

What causes faint in carotid sinus syncope?

Answer 17

Mechanical manipulation of the neck e.g. shaving, tight collar etc or after head and neck surgery or radiation

Question 18

Typical patient who suffers from carotid sinus syncope

Answer 18

Elderly male

Question 19

Treatment for carotid sinus syncope

Answer 19

Cardiac permanent pacing

Question 20

Risk factors for orthostatic syncope

Answer 20

Age, certain medications, certain diseases, reduced intravascular volume, prolonged bed rest

Question 21

Cardiac syncope

Answer 21

Caused by a cardiac event resulting in a sudden drop in cardiac output

Question 22

What things can cause cardiac syncope?

Answer 22

Arrhythmias, acute myocardial infarction, structural cardiac disease, other cardiovascular disease

Question 23

Features suggesting cardiac syncope

Answer 23

Syncope during excretion or when supine, presence of a structural cardiac abnormality or coronary heart disease, family history of sudden death at young age, sudden onset palpitations followed immediately by syncope, findings on ECG suggestive of arrhythmic syncope