A key clinical finding is the presence or absence of impaired or loss of consciousness during the episode.
Conditions associated with an altered level of consciousness:
(1) vertebro-basilar transient ischemia attack
(2) intoxication
(3) seizure disorder
(4) hypoglycemia, hypoxia, hypocapnia (from hyperventilation) or other metabolic cause
Conditions not associated with an altered level of consciousness:
(1) drop attack
(2) transient ischemic attack associated with carotid artery disease
(3) cataplexy
(4) psychogenic disorder (somatization disorder such as hysteria or a conversion reaction with somatic complaints)
A patient may have more than one of these conditions so each episode should be considered separately.
If one or more of these conditions is suspected then the evaluation will focus on those. However, the patient still needs to be screened for conditions that may cause true syncope (i.e., diagnosis of exclusion).
