Design issues of a randomised controlled clinical trial on spinal cord stimulation in critical limb ischaemia. ESES Study Group.

Abstract

Review of the design of a clinical study to evaluate of the efficacy of epidural spinal cord electrical stimulation (ESES) as compared to best medical treatment in patients with nonreconstructible critical limb ischaemia. Randomised controlled clinical trial of pragmatic type, which will be analysed according to the intention-to-treat principle. The treatment strategies are ESES, in addition to best medical treatment, and best medical treatment alone. Patients are followed-up for at least 18 months. The ESES-trial is an ongoing multicentre trial in 17 hospitals in The Netherlands. Patients with critical limb ischaemia, nonsuitable for either primary intervention or reintervention after failing reconstructions. Limb survival, patient survival, quality of life and cost-effectiveness. From November 1991 until May 1994 120 patients had been enrolled. Using life-table analysis, at one year 76% of these randomised patients were alive: 41% without amputation and 35% with amputation. Quality of life of the trial patients was low, even compared to other severely ill patient groups, such as liver and heart transplant candidates. Considering the high incidence of death and amputation, 18 months of follow-up seems adequate to detect a clinically relevant outcome improvement from ESES-treatment, if present. We hope to present the results of this study at the end of 1995.