Predictive Value of Skin Perfusion Pressure After Endovascular Therapy for Wound Healing in Critical Limb Ischemia

Purpose: To determine the predictive value of skin perfusion pressure (SPP) for wound healing after endovascular therapy (EVT). Methods: Between May 2004 and March 2011, 113 consecutive patients (84 men; mean age 71.5 +/- 12.5 years) with CLI (123 limbs) underwent successful balloon angioplasty +/- stenting (flow from >1 vessel to the foot without bypass) and were physically able to undergo SPP measurement before and within 48 hours after EVT. The status of wound healing was recorded over a mean follow-up of 17.4 +/- 12.4 months. Results: The wound healing rate was 78.9% (97 limbs of 89 patients). SPP values after EVT were significantly higher in these patients than in the 24 patients (26 limbs) without wound healing (44.2 +/- 15.6 mmHg vs. 27.5 +/- 10.4 mmHg, p<0.001). Receiver operating characteristics analysis of SPP after EVT to predict wound healing had an area under the curve of 0.81 (95% CI 0.723 to 0.899, p<0.001). The optimal cutoff for predicting wound healing was 30 mmHg, with a sensitivity of 81.4% and a specificity of 69.2%. Binary logistic regression analysis demonstrated SPP after EVT to be an independent predictor of wound healing (p<0.001). The probability of wound healing with SPP values >30 mmHg, 40 mmHg, and 50 mmHg were 69.8%, 86.3%, and 94.5%, respectively. Conclusion: SPP after EVT is an independent predictor of wound healing in patients with CLI. In our study, an SPP value of 30 mmHg was shown to be the best cutoff for prediction of wound healing after EVT.