Breath-holding Spells and Reflex Anoxic Seizures

Breath-holding spells (BHS) and reflex anoxic seizures are nonepileptic paroxysmal events. They are benign but can be frightening to parents and others observing the episodes. They are involuntary events with an incidence of 4.6% to 4.7%. The age of onset is typically between 6 and 18 months. BHS are classified by the color change manifested in the child during an event. Cyanotic episodes are more common than pallid, and mixed episodes have features of both cyanotic and pallid BHS. Pallid episodes are often provoked by fright or sudden pain, while cyanotic episodes are more often triggered by anger or frustration. The pathophysiology of cyanotic spells is complex and not completely understood but likely is at least in part due to autonomic dysfunction. Excessive vagal tone leading to cerebral hypoperfusion is the underlying cause of pallid spells. The diagnosis is made by the history. Reflex anoxic seizures result from cardiac asystole of vagal origin. They may be characterized by opisthotonic posturing and brief myoclonic jerks, but electroencephalograms during the events do not show epileptic discharges. Treatment of both BHS and reflex anoxic seizures focuses on explaining the nature of the events to the parents and reassuring them that the episodes are not epileptic seizures and do not need treatment with antiepileptic medication. BHS generally decrease in frequency during the second year of life, and by 4 years of age 50% will no longer be having episodes. Almost all BHS stop by age 7 to 8 years.