A Pilot Study Investigating the Use of Regional Oxygen Saturation as a Predictor of Ischemic Wound Healing Outcome after Endovascular Treatment in Patients with Chronic Limb-Threatening Ischemia

Objective: To determine the prognostic value of regional tissue oxygenation saturation (rSO(2)) for ulcer healing after endovascular treatment (EVT) of peripheral arterial disease (PAD). Materials and Methods: Among PAD patients, 34 patients with chronic limb-threatening ischemia underwent EVT for limb salvage. We retrospectively analyzed the cutoff rSO(2) values on postoperative day 1 to predict ulcer healing and patient prognosis. Skin perfusion pressure (SPP) and transcutaneous oxygen pressure (TcPO(2)) were also used to assess wound healing. Results: A finger-mounted tissue oximeter can easily measure rSO(2) on the dorsal foot. Among the 34 patients, the ulcer healed in 25, and no changes were observed in 2 patients at 1 month after EVT. However, 7 patients needed major amputation at the same time. Wound healing was achieved in all patients with rSO(2)≥50%. With this cutoff, the sensitivity and specificity of the new device for wound healing were 100% and 64%, respectively. In all the wound healing cases, SPP was ≥45 mmHg, and TcPO(2) was ≥40 mmHg. Conclusion: To assess limb ischemia, rSO(2) can be measured quickly and easily using this device. We suggest that an rSO(2)>50% shows good prognosis for ulcer healing.