Approach to transient loss of consciousness and syncope in children

Abstract

Transient loss of consciousness (TLOC) encompasses a group of disorders with four common presenting features which include loss of consciousness, that is transient in nature, self-limited, and not due to a trauma of the head and brain, when no probable cause can yet be identified. There are three main categories of TLOC in children and young people. The first is syncope: TLOC resulting from a sudden and reversible lack of oxygenated blood supply to the brain, often caused by transient impairment of cardiac output or systemic arterial hypotension. Secondly, TLOC due to an epileptic seizure, i.e. typically due to excessive and hypersynchronous cortical neuronal electrical activity in the brain. Thirdly a€œUnexplained TLOCa€ which includes cases not yet diagnosed fully and those for which a pathophysiological mechanism has not been identified despite thorough investigation, it includes episodes that may be due to emotional or psychogenic mechanisms or abnormal illness behaviour. This review will describe an approach to the diagnosis and management of children and young people with TLOC, and especially syncope.

Keywords

• TLOC, Syncope, Reflex Asystolic Syncope, Reflex Anoxic Seizure, Breath holding, Expiratory Apnoea Syncope, investigations