Clinical validation of the Deltatrac monitoring system in mechanically ventilated patients

Abstract

Objective: To evaluate a monitor of pulmonary gas exchange (Deltatrac, Datex) in a clinical setting. Design: After in vitro evaluation, comparison over 2 min between {Mathematical expression} and {Mathematical expression} values measured by the Deltatrac and the Douglas bag technique. Comparisons were also achieved over 8 h periods between the Deltatrac and a system using a mass-spectrometer. Setting: Polyvalent intensive care unit (ICU 15 beds) in a 1200 bed general hospital. Patients: Comparison with the Douglas bag technique in 10 patients undergoing controlled ventilation. Comparison with the massspectrometer system in 25 other patients undergoing controlled or pressure support ventilation. Measurements and results: Compared to the results obtained by the Douglas bag technique, the bias (±2SD) for {Mathematical expression} and {Mathematical expression} was -3.5±26.6 and 6.1±12.7 ml·min-1, respectively. By comparison with the mass-spectrometer system, the bias for {Mathematical expression} and RQ was -5.8±16.0 ml·min-1 and 0.018±0.048, respectively. No drift between the two systems was observed over time. Conclusions: The Deltatrac appears suitable for {Mathematical expression} and {Mathematical expression} measurements in ventilated patients and equivalent to a mass-spectrometer system for long term measurements. © 1995 Springer-Verlag.