Dizziness

Epidemiology: 30% of 65+. Nearly all causes pathological .

Investigation

Examination:
Central & peripheral neurological system
CVS: especially postural blood pressure, must wait 2m after standing. Check for aortic stenosis, HOCM
Ear
Investigation:
CT brain (strokes), audiometry, glucose, U+Es (hydration, renal function, FBC), 24h ECG, echocardiogram
Treatment
Anti-emetics, vestibular suppressants

Benign Positional Vertigo

Claim to Fame: Most comon cause of dizziness in old age. Idiopathic.
History: Recent trauma, virus. Occurs with change in head position. Resolves quickly after. No auditory/neuro symptoms.
Examination: Rotatory nystagmus: lie the pt down & induce rapid head movement to one side (Hallpike)
Treatment: Resolves spontaneously in weeks/monthss. Exercises to provoke symptoms help some.

Labyrinthitis

Definition: Inflammation of inner ear causing dizziness & hearing loss.
History: Acute onset. Bacterial/viral infections especially URTI often precede the disease.
Treatment: Resolves spontaneously.

Meniere's

Clinical: Triad of dizziness, unilateral fluctuating hearing loss, tinnitus (but may have only one of these). Associated with syncope sometimes
Treament: Drugs to supress vestibular system (promethazine). Labyrinthectomy

Drug Related

The elderly are often on many drugs. Common culprits include:
Antihypertensives: postural hypotension
Anticonvulsants
Sedatives (benzodiazepams, antidepressants, tranquilisers)
Antibiotics
NSAIDs
Aspirin overdose: w tinnititus

Cerebrovascular Disease

Definition: Isolated dizziness not explained by stroke/TIA.
Clinical: Brainstem/cerebellar symptoms neccessary (e.g. ataxia, nystagmus)

Brain Tumours

Rare. Cerebello-pontine tumours e.g. acoustic neuroma or meningioma

Orthostatic (postural) Hypotension

Common. May be caused by anti-hypertensives.
Definition: 20mmHg difference in systolic BP between sitting & standing

Syncope

Definition: Transient loss of consciousness associated with loss of postural tone due to reductions in cerebral blood flow. Recovery is spontaneous & complete. Systolic BP falls to 70mmHg.
History: Loss of memory. 3rd party vital. May be associated with jerking of limbs and this does not necessarily imply epilepsy
Claim to Fame: Must lead to a full cardiac and neuro investigation unless obviously hypoglyacamia or vasovagal
Causes: Exclude epilepsy & hypoglycaemia

Causes

Cardiac Structure

Aortic stenosis most important (usually congenital bicuspid valves), HOCM less commonly. Both present with syncope on exertion. Also consider a massive PE and MI.
Investigation: Echocardiogram

Cardiac Conduction

In the presence of known cardiac pathology syncope will be explained by arrhythmia. Sick sinus syndrome, type II/III heart block, supra/ventricular arrythmias, failed pacemaker.
Investigation: 24h ECG or memo-ECG device

Neurally Mediated

Withdrawel of SNS tone to blood vessels (↓venous tone & ↓BP) & unopposed PS discharge (↓HR).

• Simple faint (vasovagal): stimulus
• Visceral: following e.g. micturition
• Carotid sinus hypersensitivity
• Neurocardiogenic: syncope on standing that is not the above. Due to blood pooling in legs causing bradycardia. Tilt table.
• Postural Hypotension: A number of conditions & drugs are responsible, e.g. Guillain-Barre syndrome, diuretics, dehydration, DM (denervation). Ex: postural BP
  

Treatment

The underlying cause. Cannot drive for 12m.
Postural hypotension: minimise diuretics, avoid dehydration, support stochings, ↑Na, ↑water, fludrocortisone
Neurocardiogenic syncope: Act on warning signs (lie down). Vasoconstrictors (alpha). Tilt table training.