Spinal cord stimulation: predictive parameters of outcome in patients suffering from critical lower limb ischemia. A preliminary study.

INTRODUCTION The aim of our study is to identify the assessment of metabolic and dynamic capillaroscopy parameters that may be predictive of the outcome of spinal cord stimulation in patients affected with non-revascularisable chronic critical limb ischemia. MATERIALS AND METHODS Forty patients, 16 female and 24 male, average age 69 ± 8, underwent microcirculatory screening with transcutaneous oximetry and dynamic capillaroscopy. Microcirculatory assessment was performed before temporary implantation of the spinal cord stimulation stimulator and after one month. The following metabolic parameters were considered: TcPO2-TcPCO2 and with dependent limb, difference between dependent limb and supine values (Δ TcPO2, Δ TcPCO2), change in TcPO2-TcPCO2 after stimulation. Dynamic capillaroscopy parameters were recorded. Follow-up visits were scheduled at three, six, and twelve months after implantation. The procedure was performed placing an Octrode (St. Jude Medical, St. Paul, MN, USA) on the dorsal columns of the spinal cord. RESULTS Two groups were identified on the basis of transcutaneous oximetry measurements: group A (22 patients) and group B (18 patients), responding differently to the postural test. After one month of home testing period, there was an improvement in metabolic parameters, differing from one group to the other. The morphofunctional data provided by capillaroscopy highlighted the percentage of open capillaries poststimulation as being a significant parameter, although not mentioned in previous studies. CONCLUSIONS Spinal neuromodulation is an effective therapy option in the management of patients affected by non-reconstructable chronic critical limb ischemia.