Falls, fits, faints, and funny turns
Differential diagnosis
Syncopal
- Cardiogenic syncope: arrhythmias or structural heart disease.
- Reflex syncope (aka neurally-mediated syncope), most commonly vasovagal.
- Orthostatic hypotension.
Nonscyncopal
- Epilepsy: complex partial or generalized seizures.
- Metabolic disorders including hypoglycaemia, hypoxia, and hypercapnia.
- Drugs: medical or recreational.
Falls without loss of consciousness:
- Mechanical: extrinsic cause e.g. loose carpet.
- Neurological or musculoskeletal disorders leading to gait or balance problem: ageing, delirium, stroke, Parkinson's, peripheral neuropathy, arthritis.
- Sensory deficits: site or hearing.
- Drop attack: sudden leg weakness with quick recovery. Commoner in older women. May be due to leg weakness or vertebrobasilar insufficiency, whereby atherosclerosis or cervical arthritis causes reduced blood flow to posterior circulation on looking up or to the side.
- Cataplexy: transient muscle weakness that occurs in narcolepsy.
- Psychological: functional, panic attacks, breath-holding attack.
Other funny turns:
- Transient global amnesia.
- Migraine
- Vertigo
- Delirium
Falls history
Questions
- What happened Before, After, and During.
- Banged their head? Any injury?
- Arrythmic symptoms recently or preceding the fall: palpitations, chest pain?
- Loss of consciousness, or do they remember the fall?
- Alcohol: had they been drinking?
- New medications started recently?
- Collateral history may be needed or has been reported to them.
- Ever happened before? How many, where, and are they increasing or decreasing in frequency?
History should also cover usual level of functioning in terms of mobility and ADLs.
Typical findings
- Cardiogenic syncope: no warning, can be in any position (including lying flat), may have had chest pain and palpitations at the time or recently.
- Reflex syncope: can be standing or sitting (but not lying flat), may have presyncope (nausea, pallor, sweating, visual fields narrow). Could be triggered by physical or emotional stress.
- Orthostatic hypotension: just stood up.
- Epilepsy: aura or trigger before. Can be lying flat.
What happened during:
- Cardiogenic syncope: lasts seconds to minutes, with no incontinence. Look pale during and after. May have a few clonic jerks.
- Reflex syncope: short, may have myoclonic jerks and even urinary incontinence.
- Epilepsy: tonic-clonic seizure, can be doubly incontinent and bite tongue.
What happened after:
- Cardiogenic or reflex syncope: quick recovery.
- Epilepsy: slow recovery as post-ictal.
Falls investigations
Initial assessement
- ECG is always needed.
- Lying and standing BP if orthostatic hypotension suspected.
- Bloods: FBC (anaemia), glucose.
- Check CK if there has been a long lie after a fall (hours-days on the floor before being found), as muscle stasis can lead to rhabdomyolysis.
- Brain imaging if serious head injury suspected.
Secondary referral
- Consider referral if a serious underlying condition (e.g. cardiac) is suspected i.e. you cannot confidentially diagnose vasovagal syncope or orthostatic hypotension.
- Can refer to a falls clinic, or possibly to cardiology or neurology if a specific etiology is suspected.
- Patient should avoid driving while awaiting specialist testing, then contact the DVLA as per the specialist's advice.
First-line tests:
- Ambulatory ECG monitoring in suspected arrhythmias. 48h holter monitor if frequent, external event recorder if weekly, or implantable (subcutaneous) event recorder if infrequent (less than once per 2 weeks). Can be automatically-activated or patient-activated.
- Exercise ECG for patients with exercise-induced syncope.
- Carotid sinus massage during ECG in patients >60 years old or if carotid sinus syncope is suspected. Have resus equipment nearby. May need tilt table to bring out.
- Cardiac or brain imaging if indicated.
Tilt table test:
- A 2nd line investigation for unexplained syncope, usually done after ambulatory ECG testing.
- Can diagnose reflex syncope (quick hypotensive response) or orthostatic hypotension (progressive hypotension response).
- Sensitivity and specificity is not that high.
Further options:
- Adenosine (or ATP) ECG stress testing may help diagnose SVT or heart block.
Reflex syncope
Causes
- Commonest cause of transient loss of consciousness.
- Aka neurocardigoenic syncope, or simple/uncomplicated/common faint.
- Often due to orthostatic stress: long-standing, hot weather, and/or reduced fluid intake.
- May also be caused by emotional stress: pain, emotion, blood, needles.
- 3 P's suggestive of uncomplicated faint: Postural, Provocation, Prodrome.
Situational syncope:
- Vasovagal syncope due to a specific physical trigger.
- Triggers: cough, postprandial, post-exercise, micturition, defecation.
- A common cause of syncope after exercise, though syncope during exercise is more likely to suggest cardiac pathology.
Carotid sinus syncope:
- Altered HR and BP due to hypersensitive baroreceptors.
- Syncope on minimal stimulus of the neck e.g. shaving, tight shirt collar.
Management
- Often, no specific treatment is needed. Reassure patients that there is unlikely to be a serious underlying problem.
- Advise patients to avoid triggers.
- If they feel faint coming, lie flat with legs in air (on chair or against wall) or put head between legs.
- Leg crossing or arm tensing are other maneuvers which might help.
- No need to contact the DVLA for uncomplicated vasovagal syncope.
Specific treatment only needed if recurrent and dangerous:
- Tilt training: supervised prolonged upstanding. Effects wear off quickly, however.
- β-blockers, though there is limited evidence.
- Cardiac pacing for carotid sinus syncope.
Cardiogenic syncope
Arrythmic causes
- SVT including AF (especially paroxysmal AF).
- AV block, especially 2nd degree type 2 or 3rd degree. Resulting syncope and presyncope may be called Strokes-Adams attacks.
- Sinus bradycardia, due to sick sinus syndrome or drugs such as β-blockers.
- VT. May be secondary to structural heart disease.
- Congenital: long QT (may occur on startle), Brugada, CPVT.
Structural causes
- Valve disease, especially severe aortic stenosis.
- Cardiomyopathy, especially HCM.
- And, though less common, almost any other cardiac disease: MI, pericardial disease, atrial myxoma, congenital heart disease.
- Extra-cardiac: PE, aortic dissection.
Aortic stenosis and HCM may be exercise-induced.
Management
- Treat the underlying cause e.g. with cardiac drugs, pacemaker.
- Patient should inform the DVLA.
Orthostatic hypotension
Definition
- A fall in blood pressure ≥20 systolic or ≥10 diastolic on standing.
- Typically tested by checking BP while lying or sitting, then 1 minute after standing.
Causes
- ANS dysfunction: primary (Parkinson's, multiple system atrophy) or secondary (diabetes, amyloidosis).
- Medications: anti-hypertensives, diuretics, anti-anginals, anti-arrhythmics, sedatives, anti-depressants (TCAs).
- Hypovolaemia: dehydration, haemorrhage, Addison's. In the acute setting, consider ruptured ectopic pregnancy or AAA as rare but dangerous causes of orthostatic hypotension and syncope.
Clinical features
- Syncope or pre-syncopal symptoms on standing.
- Worse in the morning.
- May cause 'coat hanger pain' across neck and shoulders, due to neck muscle hypoperfusion.
Management
- Remove causes e.g. drug.
- Physical and lifestyle steps: good fluid intake, raise head of the bed.
- Leg crossing and arm tensing may help.
- Fludrocortisone if simple measures don't work.
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