Oxygen Consumption Measurement: Agreement Between the Closed-Circuit PhysioFlex Anesthesia Machine and the Deltatrac II Indirect Calorimeter

Abstract

The PhysioFlex anesthesia machine (Dräger Inc., Lübeck, Germany) is a closed circuit anesthesia delivery device. The oxygen delivered by this device to maintain a steady-state inspired oxygen concentration is therefore a measure of the patient's oxygen consumption. This study was designed to evaluate the accuracy of the PhysioFlex for measuring oxygen consumption by comparing it with an established technology (Deltatrac II Calorimeter) for making this measurement.