Computer-based evaluation of cardiopulmonary function for the optimization of ventilatory therapy in the adult respiratory distress syndrome

A computer based evaluation system has been developed for the assessment of respiratory pressure flow dynamics, pulmonary gas exchange and ventilation perfusion interrelationships. This system is based on the acquisition of primary data on-line from intubated and ventilated patients consisting of airway pressures, ventilatory flows and mass spectrometric quantification of inspired and expired gas concentrations. The system has been applied to the study of patients with the adult respiratory distress syndrome (ARDS) following trauma and/or sepsis. The programs developed for evaluation of these data permit an interactive graphic capability to be used by the physician or the respiratory technician in a specific patient to determine the nature of the abnormalities in respiratory function. By use of this system for quantification of the extent and complications of the ARDS condition the specific ventilatory or cardiodynamic therapy can be tailored to meet the patient's physiologic needs. Techniques for optimization of conventional ventilator therapy are described and its application to the specific instances of combined high frequency ventilation or differential lung ventilation are presented. The clinical experience with this unit in a major trauma center suggests that quantitative analysis of an individual patients' respiratory dysfunction permits a precise, accurate and more effective approach to determining corrective therapy in ARDS.