Modifications in transcutaneous oxygen pressure in ischemic limbs after successful PTA

Abstract

Foot and chest transcutaneous oxygen pressure (TcPO₂), the regional perfusion index (RPI = foot TcPO₂/chest TcPO₂), and the ankle/brachial systolic blood pressure index (ABI) were calculated before and after successful percutaneous transluminal angioplasty (PTA) in 36 limbs with intermittent claudication and in 8 with rest pain. In patients affected by intermittent claudication pain-free (PFWT) and maximum walking times (MWT) and the half-recovery time (HRT) to TcPO₂ basal values after an induced ischemia were also determined. After PTA, rest pain disappeared in the 8 severely ischemic lower limbs and significant differences were observed in the RPI, which increased by 215% from 0.19 ± 0.10 to 0.60 ± 0.13 (p<0.0001). In patients with intermittent claudication the RPI and the TcPO₂ HRT in particular improved significantly (p<0.0001) (RPI: from 0.68 ± 0.18 to 0.85 ± 0.20; HRT: from 120 ± 27 to 75 ± 37 s). These modifications were associated, in the 24 patients who performed a standard treadmill test, with the disappearance of claudication or with a significant improvement in their walking capacity. The ABI was not calculated in 12 limbs because the arteries could not be compressed but it significantly improved in the other limbs in the stage II peripheral arterial occlusions disease (PAOD) patients.

These results indicate that substantial increases in TcPO₂ parameters can be observed after successful PTA and that these measurements are an appropriate noninvasive method of assessing the results of revascularization procedures.