Influence of clinical findings, positional manoeuvres, and systolic ankle arterial pressure on transcutaneous oxygen tension in peripheral arterial occlusive disease

. The mutual effects of systolic ankle arterial pressures, positional manoeuvres, and calf artery occlusions on transcutaneous oxygen partial pressures (tcpO 2 ) were studied in 388 legs of 258 patients with peripheral arterial occlusive disease (PAOD). The tcpO 2 ‐vs‐perfusion pressure relationship could be satisfactorily fitted by a non‐linear regression model deduced from the tcpO 2 theory. Flow‐insensitive ranges of tcpO 2 ‐vs‐flow hyperbolas were reduced by both leg lowering and moving the electrode towards proximal measuring sites. Lower tcpO 2 values were found in case of occluded compared to patent calf arteries at ankle arterial pressure indices below 0.4. The tcpO 2 positional variability increased with worsening hemodynamic compensation and was most pronounced in critical limb ischaemia (ischaemic rest pain, non‐healing ulcerations). According to a retrospective analysis, a critical ischaemia could be assumed if supine and sitting tcpO 2 ‐values exceed neither 10 nor 45 mmHg, respectively.