Abstract
The heart, lungs and hemoglobin form the body's gas transport system, which links the atmosphere and its supply of O 2 with tissue, while simultaneously providing for the elimination of the metabolic end-product, CO 2, into the atmosphere. The transport of these respiratory gases must be in accordance with metabolic need. This is particularly evident during the physiologic stress of isotonic exercise, when the O 2 requirements and CO 2 production of skeletal muscle are increased. The monitoring of these respiratory gases during exercise, referred to as cardiopulmonary exercise testing (CAR-PET), can be used to assess heart and lung function in patients with cardiovascular or lung disease or both. Chronic cardiac failure (CCF) may be defined in physiologic terms as that circumstance in which the heart fails to provide tissue with O 2 at a rate commensurate with aerobic requirements. In patients with CCF, CAR-PET represents a noninvasive means to determine aerobic capacity (that is, maximal O 2 up-take) and anaerobic threshold during incremental treadmill exercise. It can also provide an objective measure of the severity of failure, the functional status of the patient and the heart's pump reserve. By using additional measurements of ventilation, arterial O 2 saturation and, in selected cases, hemodynamic monitoring, the nature and severity of cardiovascular and pulmonary disease may be evaluated.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call