Is it syncope? Differential diagnosis of transient loss of consciousness in the emergency department

Introduction. To define with certainty syncope, global cerebral hypoperfusion is needed. However, in the Emergency Department (ED), syncope can be sometimes hardly distinguished by other causes of transient loss of consciousness (TLOC), thus making global cerebral hypoperfusion an ineffectual criterion. The aim of the present study was to evaluate how frequently, in the ED setting, doctors are unconfident of a syncopal etiology. Matherials and Methods. Among a period of three months all consecutive patients evaluated in a single city hospital ED for possible syncopal events were selected. Among those, the authors have analyzed the ones for which the ED physician was not confident with the possible etiology of the loss of consciousness. Results. 213 patients with possible syncopewere enrolled. Among 45 of those, the ED physicianwas not sure of a syncopal etiology. In further 34 cases he was doubtful if the patient had had a definite TLOC, while for 11 patients he could not be decide between syncope or another cause of TLOC (mainly epilepsy). Conclusions. For roughly 20% of patients evaluated in the ED for possible TLOC the ED physician cannot surely differentiate between syncope and other TLOC. The limits of the present syncope definition should be recognized and a consensus for a new syncope definition to be used in the ED could be useful.