Effects of ambulation on foot oxygen tension in limbs with peripheral atherosclerosis

As walking a few steps increases the arteriovenous pressure difference for blood flow through the feet, we studied the effect of a brief period of walking on transcutaneous oxygen tension (tcPO2). Foot tcPO2 was measured using Clarke type electrodes before, during and after a brief period of repetitive walking on the treadmill in 15 patients with various degrees of arterial obstruction. TcPO2 was significantly higher during walking, than while standing on the treadmill, in limbs with severe disease manifested by toe systolic pressure <30 mmHg (mean change 0.7 kPa or 5 mmHg, P=0.001). Also, supine tcPO2 was significantly higher following periods of walking than before in limbs with toe pressure both below and above 30 mmHg (mean change 1.5 kPa or 11 mmHg, P<0.001). The results indicate that a brief period of walking increases skin oxygenation. Regimens of such exercise may promote healing in some limbs with arterial disease.