Clinical evaluation of a continuous oxygen consumption monitor in mechanically ventilated patients

Abstract

SummaryWe measured oxygen consumption using a new noninvasive modular metabolic monitor, M-COVX TM , in ventilated critically ill patients. Oxygen consumption was measured continuously as part of routine monitoring for up to 24 h following mechanical ventilation in 27 patients admitted to a general intensive care unit. We explored several possible sources of error. Most errors related to inaccurate tidal volume measurement, which resulted in rejection of a median 14% (interquartile range 8-34%) of data. Water accumulation in the pneumotachograph was responsible and occurred more frequently with water bath humidifiers. After manual removal of erroneous data mean oxygen consumption values were virtually identical to calculated values in 24 of 27 patients. We conclude that in most ventilated patients averaging of continuous oxygen consumption data with the M-COVX module results in small errors.

Increase of Oxygen Consumption during a Progressive Decrease of Ventilatory Support Is Lower in Patients Failing the Trial in Comparison with Those Who Succeed

“…We used a commercial device, based on the principle of indirect calorimetry to measure V O 2 in our patients; this system has the advantage of being noninvasive (requiring only a small connector at the circuit Y) and of providing continuous measurements of V O 2 . In our study we found a good reproducibility of the V O 2 measurements obtained during two different study phases; the system has been validated mainly by comparisons with the previous Deltatrac monitor, 14,28,29 showing a good reliability. Although the different inspiratory flow profiles have not been found to affect measurement reproducibility, 30 no data are available on the potential effect of different tidal volumes or respiratory rates.…”

Isocapnic hyperventilation shortens washout time for sevoflurane – an experimental in vivo study

“…[12][13][14] Data were continuously collected by dedicated software (Collect S5, GE Health Care, Finland). Body temperature was monitored by a rectal probe and kept normal by heating pads (38.5-39°C in pigs).…”

“…Measurements of oxygen consumption (VO 2 ) and CO 2 production (VCO 2 ) were also provided by the monitor (COVX Module, GE Health care, Finland). [12][13][14] Data were continuously collected by dedicated software (Collect S5, GE Health Care, Finland). 12…”

Intravenous Thiamine Is Associated with Increased Oxygen Consumption in Critically Ill Patients with Preserved Cardiac Index

“…The NICOM uses bioreactance to estimate cardiac index by interpreting signal from adhesive sensors attached to the patient's torso, and has been validated in prior studies (12). The GE compact anesthesia monitor measures V : O 2 using a pneumotachograph and a rapid paramagnetic analyzer attached in-line with the ventilator tubing, and has been validated in critically ill, mechanically ventilated patients (10,11,13)…”