Respiratory system mechanics in ventilated patients: techniques and indications.

For the past 50 years, basic research has provided valuable insights into the concepts of respiratory system mechanics, but clinical application in the critical-care arena remains in its infancy. On the basis of the limited information that is available on critically ill patients, we believe that physicians who are responsible for the care of mechanically ventilated patients must understand the mechanical interactions between humans and machines. With measurements of flow, volume, and pressure, a more precise quantitative evaluation of the respiratory system can be obtained than with clinical assessment alone. In this article, we discuss the principles, techniques, and clinical applications of measurements of respiratory system mechanics in ventilated patients and suggest directions for further research that may prove to be clinically relevant.