Relationship between transpulmonary ^99mTc-MAA passage and the alveolar-arterial oxygen difference (A-aDO₂) in normoxic and hypoxic exercise.

<p>Line represents the result of a general linear model analysis in which the transpulmonary ^99mTc-MAA passage was linearly correlated with the A-aDO₂ (R² = 0.63), but this relationship was not dependent on the FIO₂ (p>0.05).</p

Arterial blood gases, respiratory quotient (R), and the alveolar-arterial PO₂ difference (A-aDO₂), measured at rest and at 85% of the maximal attainable wattage during the resting and exercise visits.

<p>^*indicates p<0.05 compared to values measured at rest on the same day.</p>†<p>indicates p<0.05 compared to normoxic exercise.</p

Change in the transpulmonary passage (%) of ^99mTc-MAA compared to resting, normoxic gas breathing.

<p>Dashed line indicates the repeatability coefficient (0.92%) Transpulmonary ^99mTc-MAA passage was noted in 6/7 participants performing exercise in normoxia and 4/7 participants performing exercise in hypoxia. Breathing hypoxic gas at rest increased ^99mTc-MAA passage in all participants relative to hypoxic exercise. ** indicates a difference compared to hypoxic rest (p = 0.001).</p

Anthropometric characteristics of the seven participants completing the study.

<p>FVC, forced vital capacity; FEV₁, forced expired volume in 1 second; DL_CO, diffusion capacity for carbon monoxide; VO₂max; relative maximal oxygen uptake.</p><p>^*indicates p<0.05. Values in parentheses are percent predicted (23–25).</p

Relationship between transpulmonary ^99mTc-MAA passage with exercise in normoxia vs. hypoxia (A) and between rest and exercise in hypoxia (B).

<p>The transpulmonary passage of ^99mTc-MAA with exercise in hypoxia was well-correlated with that measured at rest with hypoxic gas breathing. Dashed line indicates the line of identity.</p