Transient Loss of Consciousness (TLOC) is a very common problem affecting over 1/3 people one or more times during their lives. Two age groups are mainly affected: the young (age 15-24, mainly women) and older subjects (> 60 years of age; both men and women) (slide 1). Although patients in both groups are mainly diagnosed with vasovagal syncope (VVS) (68% of young and 34% of older subjects), older subjects also frequently suffer from carotid sinus syncope (7%), orthostatic hypotension (17%) and cardiac disorders (20%) (slide 2).
Although young subjects are mainly diagnosed with VVS, and epilepsy and cardiac syncope are rare in this age group, missing such a serious diagnosis could be lethal. Fortunately, specific elements from history can distinguish reflex syncope from cardiac syncope (slide 3) and epilepsy (slides 4 and 5). In younger subjects therefore a thorough history, physical examination and ECG are usually sufficient a make a diagnosis. Head-up tilt testing can be used to confirm the diagnosis of VVS and teach the patient about the disorder. Initial Orthostatic Hypotension is a more rare, but often missed cause of dizziness and syncope in young asthenic subjects and can be tested only by an active standing test with continuous blood pressure monitoring.
In older subjects, the diagnosis can be more difficult, since they do not only have a higher probability of suffering from other diagnoses than VVS, but also display less, and less specific symptoms. Besides cardiac causes of syncope, the diagnoses orthostatic hypotension and carotid sinus syncope should be excluded in older subjects, using active standing tests and carotid sinus massage preferably with continuous blood pressure and HR monitoring.
Since the causes of syncope differ between younger and older subjects, also treatment options differ between both groups (slide 6). In subjects with reflex syncope, counseling, lifestyle advises, raising water- and salt-intake and training in physical counterpressure manoeuvres are first line treatment options. Psychological treatment can be useful in subjects with syncope induced by blood phobia. The use of pharmacological interventions and pacemakers in young subjects is still under debate. In patients with autonomic failure, abdominal binders or pharmacological treatment can be effective. Pacemakers are recommended for patients with carotid sinus syndrome.
Unidades de síncope en Urgencias
Dr. Juan José Olalla
Empleo de fármacos. Una visión crítica
Dr. Roberto García Civera
Blog Impulso Vital - Fundación Española del Corazón