Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
A colloquial term for an episode of severe hypoxia and cyanosis in a child with tetralogy of Fallot. During a spell, blood from the right ventricle flows across the defect in the child's interventricular septum, bypassing the pulmonary artery and lungs, thus depriving the child of oxygen.
Medical Dictionary, © 2009 Farlex and Partners