Background: Transcutaneous oxygen pressure (tcpO2) reliability is blunted by an unpredictable transcutaneous gradient through the skin. We hypothesized that the "Decrease from Rest of Oxygen pressure (DROP: subtraction of limb-changes from chest-changes from the respective starting values) would show a good to excellent reliability during Exercise -tcpO2 investigations.
Methods: In three different experiments we tested: The intra-test variability at the peripheral level (Experiment A: 32 patients, 16 at each location), at the chest level (Experiment B: 45 patients) and the test-retest reproducibility within 3 months (Experiment C: 67 patients).