Related Experiment Video
Updated: Apr 19, 2026

Assessing Changes in Synaptic Plasticity Using an Awake Closed-Head Injury Model of Mild Traumatic Brain Injury
Published on: January 20, 2023
History of syncope predicts loss of consciousness after head trauma: Retrospective study
Dorota Zyśko1, Richard Sutton, Dariusz Timler
1Department of Medical Emer gency, Wroclaw Medical University, Wroclaw, Poland. dzysko@wp.pl.
Background:
Head trauma may present as transient loss of consciousness (TLOC) currently classified as traumatic in origin, in contrast to non-traumatic forms, such as syncope. Whether past history of syncope predisposes to loss of consciousness after head injury has been poorly studied.
Methods:
A retrospective analysis of data obtained from 818 consecutive patients admitted to Emergency Departments was conducted. Face-to-face semi-structured interviews were performed, where patients' past history of syncope and head injury were explored. Head injury events were stratified as high- or low-energy trauma. Data regarding past syncopal events were explored in regard to number, age at the first occurrence, and syncope circumstances. Multivariate logistic regression model was applied to assess the relationship between loss of consciousness during head injury and past history of syncope.
Results:
Both past history of non-traumatic TLOC (odds ratio [OR] 3.78; 95% confidence interval [CI] 2.13-6.68, p < 0.001) and high-energy mechanism (OR 3.84; 95% CI 2.35-6.28, p < 0.001) predicted TLOC after head trauma. This relationship was even stronger when past episodes of TLOC were limited to those typical for reflex syncope (OR 4.34; 95% CI 2.34-7.89, p < 0.001). Further, the number of non-traumatic TLOC episodes in the patient's history was also predictive of TLOC after head injury (OR per 1 episode: 1.24; 95% CI 1.04-1.48, p = 0.015).
Conclusions:
Syncope in a patient's history predicts loss of consciousness after head injury. The clinical importance of this finding merits further investigation.
More Related Videos
Related Concept Videos
Traumatic Brain Injury l: Introduction
Increased Intracranial Pressure ll: Pathophysiology
Transient Ischemic Attack l: Introduction
Amnesia
The severity and duration of memory loss vary depending on the type and underlying cause. Amnesia is classified into two main types: retrograde and anterograde.
Retrograde amnesia is marked by the loss of memories formed before the onset of the condition. Patients may recall distant past events but often forget those occurring shortly before the incident.
Anterograde...
Hemorrhagic Stroke ll: Pathophysiology
Cerebral Edema ll: Pathophysiology

