Spinal cord stimulation in the treatment of non-reconstructable stable critical leg ischaemia: results of the European Peripheral Vascular Disease Outcome Study (SCS-EPOS).

OBJECTIVE: To determine the effect of spinal cord stimulation (SCS) on limb survival in patients with non-reconstructable critical leg ischaemia, and the value of patient selection on the basis of transcutaneous oxygen pressure (TcpO2) measurements and trial screening. DESIGN: A prospective, controlled, European multicentre study. METHODS: Non-reconstructable patients with stable critical leg ischaemia were divided into three groups. The SCS-Match group comprised patients with a baseline forefoot TcpO2 of < 30 mmHg and both sufficient pain relief and sufficient paraesthesia coverage (> 75%) after a test stimulation period of at least 72 h. If baseline TcpO2 was < 10 mmHg, the TcpO2 should have exceeded 20 mmHg after test stimulation. The SCS-Match group was compared with patients not meeting these criteria, who were treated either with SCS (SCS-No-Match) or without SCS (No-SCS). RESULTS: At baseline, the mean (+/- SD) supine TcpO2 was 14.9 +/- 8.3 mmHg in the SCS-Match group (n = 41), 11.3 +/- 13.3 mmHg in the SCS-No-Match group (n = 32) and 15.3 +/- 17.1 mmHg in the No-SCS group (n = 39). In the SCS-Match group a significant improvement in pain relief (p < 0.005) and TcpO2 (p < 0.001) was seen. After 12 months, cumulative limb survival of patients treated with SCS was significantly better than that of patients not treated with SCS (p < 0.03), and limb survival in the SCS-Match group was significantly higher (p < 0.03) than that in the SCS-No-Match and No-SCS groups (78, 55 and 45%, respectively). CONCLUSION: SCS treatment of non-reconstructable critical leg ischaemia provides a significantly better limb survival rate compared with conservative treatment. Patient selection based on TcpO2 and the results of trial screening further increase the probability of limb survival after SCS therapy.

The best TcpO(2) parameters to predict the efficacy of spinal cord stimulation to improve limb salvage in patients with inoperable critical leg ischemia.

AIM: Spinal cord stimulation (SCS) is available as an alternative therapy for patients suffering from inoperable critical limb ischemia (CLI). Selection of patients is essential to achieve the best treatment effect. For this purpose transcutaneous oxygen (TcpO(2)) measurements have frequently been applied. So far, it is unclear which TcpO(2) parameters serve this purpose best. METHODS: Studies in which inoperable CLI patients were treated with conservative treatment with or without SCS, and in whom various TcpO(2) measurements were performed before and during treatment were pooled to investigate which TcpO(2) parameter(s) were best to detect patients who benefit most from SCS treatment as to limb salvage. RESULTS: TcpO(2) in the supine position increased significantly (p<0.001) in patients after a short period of SCS treatment (from 9 to 22 mmHg), but not in those treated conservatively (from 7 to 7 mmHg). Baseline supine TcpO(2) (using a cut-off value of 10 mmHg), the baseline sitting-supine TcpO(2) difference (cut-off value: 17 mmHg), and the difference in TcpO(2) before and after test stimulation (cut-off value: 4 mmHg) were related to a significantly increased limb salvage. SCS patients with a sitting-supine TcpO(2) difference of >17 mmHg had a 1-year limb salvage of 83% vs 68% in the whole SCS-treated group irrespective of TcpO(2) selection. CONCLUSION: The TcpO(2) parameters mentioned above are capable of detecting the effect of SCS treatment. Selection using (a combination of) TcpO(2) measurements substantially improves limb salvage of patients treated with SCS for inoperable CLI.