Evaluation of the M-COVX metabolic monitor in mechanically ventilated adult patients

SummaryBackground & aimsIndirect calorimetry is commonly used for energy expenditure studies. However, older metabolic carts can be cumbersome and difficult to use. This study was aimed at validating the new M-COVX indirect calorimeter.MethodsThis prospective study was performed in all ventilated critically ill adults, with a Fractional Inspired Oxygen <60%, respiratory rate below 35 breaths-per-minute and endotracheal tube leak <10%. Patients were studied in steady-state only. Repeated, sequential measurements were performed comparing Deltatrac II NMN-200 to the new M-COVX. For each instrument, 5 consecutive, 1 min measurements of volume of oxygen and carbon dioxide, respiratory quotient and energy expenditure were recorded.ResultsOf the 20 patients enrolled in the study, the data of 11 patients was used for analysis. Bland Altman plots indicated clinically significant differences between the 2 indirect calorimeters for volume of oxygen (19.2%) and carbon dioxide (17.6%) and energy expenditure (15.3%).ConclusionThe results show that the M-COVX metabolic monitor might not provide measurement within a clinically accepted range in certain ventilation modes and in non-sedated patients. Further research has to be performed to confirm our findings.