ABSTRACT
INTRODUCTION Breathing difficulty is a common medical problem. The initial part of this chapter consid ers the related questions “ What is dyspnea?” and “ What causes dyspnea?” The three types of dyspnea based on the temporal features (acute onset, development with specific body positions, and chronic nature) are described. Guidelines are presented to help the health care provider apply information obtained from the medical history and physical examination so as to select appropriate tests to diagnose the cause of dyspnea. Diagnostic testing directed at the most likely cause of dyspnea is recommended, rather than a “ shot gun” approach.
