Assessment of lung function in the intensive care unit.

Tests of pulmonary function have become more accurate and less invasive in recent years. Our ability to monitor patients continuously with pulse oximetry, transcutaneous and end-tidal CO2, and intraarterial blood gas monitors has greatly enhanced ICU care. In intubated patients in the PICU detailed lung function studies can be performed, and in general they can be carried out with minimal disruption of routine management. Much work remains to be done to define the changes seen in various disease processes and the effects of therapeutic interventions on functional parameters. Many of the available techniques have already been developed to a point that allows them to be employed in clinical decision making. We expect that assessment of lung volumes, compliance, and resistance will become a routine part of management in children with life-threatening pulmonary diseases in the near future, and that a more intimate knowledge of the pathophysiology of respiratory disorders treated in PICU will lead to improved outcomes.