A validation study of the KB1-C portable metabolic measurement system using the autocalibration feature

[摘要] The purpose of this study was to determine the validity of the Aerosport KBI-C portablemetabolic measurement system (Aerosport, Ann Arbor, MI) using the autocalibrationfeature against the Quinton QMC metabolic measurement cart. Twenty healthy 18-30year old men and women volunteered to participate in this study. All subjects werestudents, faculty, or staff of the University of Wisconsin-Lacrosse. Volume and gascalibrations were completed according to the specifications of the manufacturer.Validation of the QMC ventilation measurements was determined by the subjectsperforming an exercise test on a treadmill consisting of a standard warm-up at 3.5 mphand 10% grade, followed by 3, 5 minute workloads at a self-selected speed at inclines of0,2.5, and 5% grade. During this test, exhaled air was routed into the QMC and out theexhaust port into a Tissot spirometer during the final minute of each stage. Once theminute sample was collected in the Tissot, the air was forced out the exhaust port of theTissot spirometer and through the mouthpiece of the KBl-C. Ventilation (VE) valuesmeasured by the KBI-C (STPD), QMC (BTPS), and Tissot spirometer (ATPS) were thenconverted to a standard volume (STPD) for comparison purposes. Comparison ofphysiological measures between the KBI-C and QMC was accomplished by each subjectperforming the same exercise test protocol as described above. During this test, exhaledair was routed into the QMC and out the exhaust port through the mouthpiece of theKBI-C for gas analysis. Repeated measures with appropriate post-hoc tests indicated nosignificant (p > 0.05) differences existed between the VE measures of the QMC andTissot spirometer up to 46.8 1-min; however, there were significant (p < 0.05)differences between the Tissot vs KBI -C at all workloads. When physiological measureswere compared between the KB1-C and QMC, VE data were not significantly (p > 0.05)different. No significant (p > 0.05) differences were found for measures of FE02;however, FECO2 values were significantly( p < 0.05) different with both FE02a nd FEC02values produced by the KB1-C consistently lower than the QMC. Oxygen consumptionand VCO2 data were both found to be significantly (p < 0.05) different, which producedsimilar RER values as the reference system, but cannot be termed accurate due to theerror in both VO2 and VC02. It was concluded that the KBI-C should not be utilizedusing the autocalibration procedure in a research capacity due to significant inaccuracy inmeasurements provided by the unit.

[发布机构] University of Wisconsin

[效力级别] Carbon dioxide in the body - Measurement

[关键词] Indirect calorimetry;Carbon dioxide in the body - Measurement;Oxygen in the body - Measurement;Energy metabolism