Breath-holding spells.

Two particularly common, and frequently frightening, forms of syncope and anoxic seizure in early childhood are pallid and cyanotic breath-holding spells. Pallid breath-holding spells result from exuberant vagally-mediated cardiac inhibition. Cyanotic breath-holding spells are of more complex pathogenesis, involving an interplay among hyperventilation, Valsalva maneuver, expiratory apnea, and intrinsic pulmonary mechanisms. The history is the mainstay of diagnosis; videotape documentation may be possible. Performance of an electrocardiogram to evaluate for prolonged QT syndrome should be strongly considered. In patients with pallid breath-holding spells, a characteristic sequence of changes may be documented on an electroencephalogram with ocular compression, if this study is performed. Spontaneous resolution of breath-holding spell, without sequelae, is anticipated. Reassurance is the mainstay of therapy. Occasionally, pharmacologic intervention may be of benefit.