Assessment of accuracy of the Vacu-Med 17053 calibrator for ventilation, oxygen uptake (V(O(2))), and carbon dioxide production (V(CO(2))).

BACKGROUND Few have examined the accuracy of mechanical calibrators used to calibrate metabolic monitors. OBJECTIVE To evaluate the Vacu-Med 17053 motorized syringe calibrator for accuracy against the accepted standard method: the Douglas bag. METHODS We tested oxygen consumption values (V(O(2))) of 522-3,210 mL/min. We mixed room air and calibration gases in the pumping syringes of the Vacu-Med 17053 and evacuated those gases into a Douglas bag, measured the Douglas bag volumes and concentrations, and converted to pulmonary ventilation, V(O(2)), and carbon dioxide production (V(CO(2))). RESULTS The Vacu-Med 17053 calibrator overestimated V(O(2)) by a mean 28.6 mL/min (1.3% error), underestimated V(CO(2)) by 6.9 mL/min (-1.7% error), and underestimated pulmonary ventilation by 0.98 L/min (-1.4% error). The V(O(2)) and V(CO(2)) differences between the calibrator and the Douglas bag were larger at higher V(O(2)) levels. CONCLUSIONS The V(O(2)) and V(CO(2)) differences might be attributable to fluctuations of the calibrator settings. The Vacu-Med 17053 calibrator was accurate with the application of a mathematical correction.