Effect of Arterial Revascularization on Transcutaneous Oxygen Tension of the Ischemic Extremity

In 20 patients (24 limbs) with peripheral occlusive arterial disease involving the lower extremities, foot and chest transcutaneous oxygen tension (tcPo₂) and ankle and arm systolic blood pressures were measured, with the patient's legs horizontal and with them in an elevated position, before and after revascularization procedures. Eighteen of the procedures were unilateral and were performed to alleviate severe ischemia; the three bilateral procedures were done to relieve intermittent claudication. Regional perfusion index (RPI) was calculated for each foot (RPI = tcPo₂ foot/tcPo₂ chest) with the legs horizontal and with the legs elevated for 3 minutes (RPI₃). The ankle/brachial index was calculated from ankle and arm systolic blood pressures. Limbs with severe ischemia had considerably decreased RPI and RPI₃ before revascularization, whereas limbs affected by claudication had only a modest decrease in RPI but a pronounced decrease in RPI₃. The tcPo₂, RPI, and RPI₃ increased substantially after revascularization.