Hyperventilation Syndrome

THE HYPERVENTILATION syndrome is a common, often disabling, and frequently inadequately treated clinical problem. Diagnosis is often missed, perhaps because physicians are not sufficiently aware of it or because patients rarely demonstrate the classic textbook picture of obvious overbreathing, paresthesia, and tetany. More commonly, symptoms are subtle and often mimic those of other clinical conditions, either organic or functional. Indeed, many patients with this affliction wander from one physician to another either vainly undergoing increasingly complex diagnostic procedures or being dismissed as anxious or neurotic. The purpose of this brief review is to emphasize the clinical importance of this syndrome, its common clinical signs and symptoms, and its metabolic and physiologic consequences, and to define effective management. DEFINITION AND INCIDENCE Hyperventilation is defined as ventilation in excess of that required to maintain normal blood Pao₂and Paco₂. It may be produced either by an increase in frequency or