Physiologic Considerations in the Diagnosis and Treatment of Ventilatory Insufficiency

Fig. 1.  —Some of the structures whose integrated activity is required for efficient and easy breathing."Ventilatory insufficiency" is a brief expression used to indicate a complex situation that exists when an abnormality in the mechanical aspects of breathing is accompanied by dyspnea at moderate levels of physical activity.The numerous structures contributing to breathing (Fig. 1) emphasize the complexity of the actual mechanics of breathing. Fenn ¹ has aptly stated, "... the mechanics of breathing is a problem requiring on one hand the detailed knowledge of a classical anatomist and on the other hand the analytic understanding of an engineer." It may be permissible to add that much remains to be accomplished in the synthesis of understanding of (1) how the integrated activity of the breathing structures is maintained in health or lost to varying degrees in disease and (2) the basis and mechanism of dyspnea.In recent years, however,