Hypoxia, hypoglycaemia | Should be picked up in primary survey |
Do not forget the glucose |
Epilepsy* | Previous history, postictal period |
Affective (psychological) | History of anxiety or panic disorder, hyperventilation |
Dysfunction of brain stem—for example, vertebrobasilar transient ischaemic attack, basilar migraine | Cerebellar signs on neurological examination |
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Heart—for example, ischaemic heart disease | Recent chest pain, history of myocardial infarction |
Emboli—pulmonary embolism | Pleuritic chest pain, dyspnoea, calf pain, or swelling |
Aortic obstruction—for example, stenosis, hypertrophic obstructive cardiomyopathy (HOCM)† | Precipitated by exertion, cardiac murmur on auscultation |
Rhythm disorders—for example, sick sinus syndrome, complete heart block | May be picked up on primary survey if heart rate <50, history of ischaemic heart disease |
Tachydysrhythmias—for example, SVT, VT, long QT syndrome | History of palpitations, may be picked up on primary survey if heart rate >100, <5 s prodromal period |
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Vasovagal* | Prodrome of nausea, dizziness, yawning, sweaty |
ENT—for example, Ménière’s disease, acute labyrinthitis, benign paroxysmal positional vertigo | History of vertigo, deafness, tinnitis. nystagmus on neurological examination |
Situational—for example, fright, micturition, deglutition, defaecation | May be apparent from history |
Sensitive carotid sinus | Precipitated by head movement |
Ectopic pregnancy** | History of abdominal pain, amenorrhoea, PV bleeding, positive pregnancy test |
Low vascular tone | |
Subclavian steal** | Precipitated by upper arm exertion |
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DRUGS—for example, antihypertensives, sympathetic blockers causing postural hypotension* | Elderly patient on multiple drugs |
Postural fall in blood pressure |