Syncope

Question 1

What is syncope

Answer 1

The brain requires a constant supply of blood, oxygen and glucose to maintain function.

Syncope is caused by cerebral hypoperfusion and is associated with both transient loss of consciousness and loss of postural tone.

Question 2

What causes syncope

Answer 2

Postural hypotension
- sitting to standing / prolonged episodes of standing still

Vasovagal syncope
- overstimulation of the vagus nerve causes a bradycardia episode
- pain / fear common causes of vagus nerve stimulation

Cardiac syncope
- sudden arrhythmia / structural changes such as pulmonary embolism or coronary thrombosis

Question 3

ABCDE assessment syncope

Answer 3

Airway - normal

Breathing - increased respiratory rate / hypoxia may be signs of cardiac related syncope

Circulation -
- high heart rate, resolves quickly as pt recovers (normal compensatory mechanism)
- persistent bradycardia, tachycardia, arrhythmia (cardiac related syncope)
- persistent low blood pressure / capillary refill times (cardiac related syncope)

Disability - If low capillary blood glucose, treat as hypoglycaemia
Brief unresponsiveness
Pain from possible injury

Exposure - pale skin / possible injury

Question 4

Rule out syncope red flags

Answer 4

• most are benign (postural hypotension / vasovagal)
• if episode is prolonged / recovery incomplete, consider hypoglycaemia / hypoxia
• syncope not associated with erratic muscle movement

Question 5

Benign syncopal episode

Answer 5

Duration - 20-30 seconds
Recovery - spontaneous / complete
Warning - pre syncopal warning signs (dizzy, faint, nausea, visual disturbances)
Recurrence - no returning when returning to upright position
Cardiac history - no significant cardiac history
Position - syncope from seated or standing

Question 6

Red flag syncopal episode

Answer 6

Duration - in excess of 4 mins (check capillary blood glucose (CBG) and pulse oximetry)
Recovery - remains drowsy/vague (check capillary blood glucose (CBG) and pulse oximetry)
Warning - no warning signs
Recurrence - recurrence when returning to upright position
Cardiac history - significant cardiac history
Cardiac symptoms - cardiac symptoms preceding syncopal episode (chest pain, bradycardia, palpitation)
Position - syncope when supine

Question 7

Syncope management

Answer 7

1. Postural manoeuvres (lay flat, elevate legs)
2. Identify red flags / offer complex carbs, water / administer first aid if required
3. Discharge / escalation
   - if red flags identified, call 999
   - if no red flags, plan for safe discharge on pt recovered