PT - JOURNAL ARTICLE AU - Smallwood, Craig D AU - Kheir, John N AU - Walsh, Brian K AU - Mehta, Nilesh M TI - Accuracy of Oxygen Consumption and Carbon Dioxide Elimination Measurements in 2 Breath-by-Breath Devices AID - 10.4187/respcare.05115 DP - 2017 Apr 01 TA - Respiratory Care PG - 475--480 VI - 62 IP - 4 4099 - http://rc.rcjournal.com/content/62/4/475.short 4100 - http://rc.rcjournal.com/content/62/4/475.full AB - BACKGROUND: Although accurate quantification of oxygen consumption (V̇O2) and carbon dioxide elimination (V̇CO2) provides important insights into a patient's nutritional and hemodynamic status, few devices exist to accurately measure these parameters in children. Therefore, we assessed the accuracy and agreement of 2 devices currently on the market using a pediatric in vitro model of gas exchange.METHODS: We utilized a Huszczuk simulation model, which simulates oxygen consumption and carbon dioxide production using gas dilution, to examine the accuracy of two FDA-cleared respiratory modules (E-COVX and E-sCAiOVX-00). V̇O2 and V̇CO2 were set at 20, 40, 60, and 100 mL/min, ranges typical for infant and pediatric patients. Bland-Altman analysis was used to calculate the bias and limits of agreement of each device relative to simulated values for V̇O2 and V̇CO2.RESULTS: The E-COVX mean percentage bias (limits of agreement) was −26.3% (−36.1 to −16.6%) and −39.3% (−47.5 to −31.1%) for V̇O2 and V̇CO2, respectively. The mean bias (limits of agreement) for the E-aCAiOVX-00 was −0.5% (−13.3 to 12.3%) and −6.0% (−13.8 to 1.7%) for V̇O2 and V̇CO2, respectively.CONCLUSIONS: The E-COVX demonstrated bias and limits of agreement that were not clinically acceptable; therefore, application of this module to pediatric patients would not be recommended. The new module, E-sCAiOVX, demonstrated acceptable bias and limits of agreement for the V̇O2 and V̇CO2 in the range 40–100 mL/min (which corresponds to patients in the range of ∼5–16 kg).