Spiroergometric measurements under increased inspiratory oxygen concentration (FIO2)-Putting the Haldane transformation to the test

TY - JOUR

T1 - Spiroergometric measurements under increased inspiratory oxygen concentration (FIO2)-Putting the Haldane transformation to the test

AU - Lang, Stephan

AU - Herold, Robert

AU - Kraft, Alexander

AU - Harth, Volker

AU - Preisser, Alexandra M

PY - 2018

Y1 - 2018

N2 - Spiroergometric measurements of persons who require oxygen insufflation due to illness can be performed under conditions of increased inspiratory oxygen concentration (FIO2). This increase in FIO2, however, often leads to errors in the calculation of oxygen consumption ([Formula: see text]). These inconsistencies are due to the application of the Haldane Transformation (HT), an otherwise indispensable correction factor in the calculation of [Formula: see text] that becomes inaccurate at higher FIO2 concentrations. A possible solution to this problem could be the use of the 'Eschenbacher transformation' (ET) as an alternative correction factor. This study examines the concentration of FIO2 at which the HT and the ET are valid, providing plausible data of oxygen consumption corresponding to the wattage achieved during cycle ergometry. Ten healthy volunteers underwent spiroergometric testing under standard conditions (FIO2 = 20.9%), as well as at FIO2 = 40% and 80%. When compared with the predicted values of [Formula: see text], as calculated according to Wasserman et al. (2012), the data obtained show that both the HT and ET are valid under normal conditions and at an increased FIO2 of 40%. At FIO2 concentrations of 80%, however, the [Formula: see text] values provided by the HT begin to lose plausibility, whereas the ET continues to provide credible results. We conclude that the use of the ET in place of the HT in spiroergometric measurements with increased FIO2 allows a reliable evaluation of stress tests in patients requiring high doses of supplemental oxygen.

AB - Spiroergometric measurements of persons who require oxygen insufflation due to illness can be performed under conditions of increased inspiratory oxygen concentration (FIO2). This increase in FIO2, however, often leads to errors in the calculation of oxygen consumption ([Formula: see text]). These inconsistencies are due to the application of the Haldane Transformation (HT), an otherwise indispensable correction factor in the calculation of [Formula: see text] that becomes inaccurate at higher FIO2 concentrations. A possible solution to this problem could be the use of the 'Eschenbacher transformation' (ET) as an alternative correction factor. This study examines the concentration of FIO2 at which the HT and the ET are valid, providing plausible data of oxygen consumption corresponding to the wattage achieved during cycle ergometry. Ten healthy volunteers underwent spiroergometric testing under standard conditions (FIO2 = 20.9%), as well as at FIO2 = 40% and 80%. When compared with the predicted values of [Formula: see text], as calculated according to Wasserman et al. (2012), the data obtained show that both the HT and ET are valid under normal conditions and at an increased FIO2 of 40%. At FIO2 concentrations of 80%, however, the [Formula: see text] values provided by the HT begin to lose plausibility, whereas the ET continues to provide credible results. We conclude that the use of the ET in place of the HT in spiroergometric measurements with increased FIO2 allows a reliable evaluation of stress tests in patients requiring high doses of supplemental oxygen.

KW - Journal Article

U2 - 10.1371/journal.pone.0207648

DO - 10.1371/journal.pone.0207648

M3 - SCORING: Journal article

C2 - 30540773

VL - 13

SP - e0207648

JO - PLOS ONE

JF - PLOS ONE

SN - 1932-6203

IS - 12

ER -