Cardiopulmonary Interactions

An understanding of the interactions between the respiratory and circulatory systems is essential for the optimal care of the critically ill patient. In this review, the physiological underpinnings of these interactions will be discussed, demonstrating that not only does the respiratory system profoundly impact circulatory performance but also reciprocal influences exist whereby the circulation powerfully influences respiratory mechanics. It will be shown how these reciprocal interactions are mediated not only through local mechanical influences originating with the thorax but also through centrally mediated neural mechanisms, and some of their important clinical implications will be described.