Pulmonary Pathophysiology and Lung Mechanics in Anesthesiology

The practice of thoracic anesthesia involves not only patients with impaired pulmonary function, it also necessitates dynamic changes in ventilation with resulting impact on perfusion and ventilation/perfusion matching. Thus it is imperative that the thoracic anesthesiologist has a thorough understanding of the normal pulmonary physiology, as well as states of pathophysiology. Further, he or she must have an intimate familiarity with the impact of mechanical ventilation on both normal and injured lungs, so he or she is equipped to manipulate ventilation in a way that responds to the dynamic needs of thoracic surgery, as well as the evolution of lung injury. Lung mechanics is the expression of lung function through measures of pressure and flow. In this chapter, we review normal lung structure and physiology, an overview of lung mechanics, clinical testing of lung function, and the implications and effects of anesthetics on these factors.