Emergency Medicine

ACUTE NEUROLOGICAL CONDITIONS

88 General Medical Emergencies

2 A faint may be difficult to distinguish from a seizure or acute vertigo, so an

eye-witness account is vital. Always interview ambulance crew or accom-

panying adults.

3 Causes vary from benign to imminently life threatening. The aim is to

always exclude the most serious conditions such as cardiac-related, hypo-

volaemia or subarachnoid haemorrhage:

(i) Cardiac

(a) arrhythmia, either a tachycardia or a bradycardia ‘Stokes–

Adams attack’

(b) myocardial infarction

(c) stenotic valve lesion (especially aortic stenosis)

(d) hypertrophic cardiomyopathy

(e) drug toxicity or side effect

• prolonged QT from sotalol, tricyclics, erythromycin, etc.


• calcium-channel or -blocker.
  (ii) Postural (orthostatic) hypotension
  (a) haemorrhage or fluid loss:


• vomiting and or diarrhoea, with dehydration


• haematemesis and melaena


• concealed haemorrhage (such as an abdominal aortic aneu-
  rysm or ectopic pregnancy)


• hypoadrenalism (Addison’s), hypopituitarism, pancreatitis
  ‘third spacing’
  (b) autonomic dysfunction


• Parkinson’s disease (multiple systems atrophy), diabetes
  (c) drugs:


• antihypertensives, e.g. angiotensin-converting enzyme
  (ACE) inhibitors, prazosin


• diuretics


• nitrates


• levodopa


• phenothiazines


• tricyclic antidepressants.
  (iii) Vascular
  (a) pulmonary embolism
  (b) carotid sinus hypersensitivity.
  (iv) Neurological
  (a) subarachnoid haemorrhage
  (b) vertebrobasilar insufficiency, as part of a transient ischaemic
  attack (TIA).
  (v) Cough, micturition or defecation syncope.