Microcirculatory Flux and Pulsatility in Arterial Leg Ulcers is Increased by Intermittent Neuromuscular Electrostimulation of the Common Peroneal Nerve.

BACKGROUND: Neuromuscular electrical stimulator (NMES) devices increase blood flow to the lower limb by a process of intermittent muscular contraction initiated by a transdermal stimulus to the common peroneal nerve. However, its effects on localized microvascular blood supply to lower limb wounds are unknown. This study is a single-center open label study measuring the effect of neuromuscular stimulation of the common peroneal nerve on the microvascular blood flow within the wound bed of arterial leg ulcers. METHODS: Eights patients with ischemic lower limb wounds had an NMES (geko™) applied to the common peroneal nerve. Baseline and intervention analysis of blood flow to the wound bed and edge was performed using Laser Speckle Contrast Imaging. Mean flow (flux) and pulse amplitude (pulsatility) were measured. RESULTS: Stimulation of the common peroneal nerve with the NMES resulted in a significantly increased flux and pulsatility in both the wound bed and the wound edge in all 8 patients. CONCLUSIONS: Neuromuscular electrical stimulation immediately increases microcirculatory blood flow to the wound bed and edge in patients with ischemic lower limb wounds. These data may provide mechanistic insight into the clinical efficacy of NMES in healing wounds. www.clinicaltrials.gov NCT03186560.

Perineural local anaesthetic catheter after major lower limb amputation trial (PLACEMENT): results from a randomised controlled feasibility trial.

OBJECTIVES: To determine the feasibility of undertaking a randomised controlled effectiveness trial evaluating the use of a perineural catheter (PNC) after major lower limb amputation with postoperative pain as the primary outcome. DESIGN: Randomised controlled feasibility trial. SETTING: Two vascular Centres in South Wales, UK. PARTICIPANTS: 50 patients scheduled for major lower limb amputation (below or above knee) for complications of peripheral vascular disease. INTERVENTIONS: The treatment arm received a PNC placed adjacent to the sciatic or tibial nerve at the time of surgery, with continuous infusion of levobupivacaine hydrochloride 0.125% for up to 5 days. The control arm received neither local anaesthetic nor PNC. Both arms received usual perioperative anaesthesia and postoperative analgesia. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcomes were the proportion of eligible patients who were randomised and the proportion of recruited patients who provided primary effectiveness outcome data. Secondary outcomes were: the proportion of recruited patients reaching 2 and 6 month follow-up and supplying pain data; identification of key cost drivers; development of an economic analysis framework for a future effectiveness trial; identification of barriers to recruitment and site set-up; and identification of the best way to measure postoperative pain. RESULTS: Seventy-six of 103 screened patients were deemed eligible over a 10 month period. Fifty (64.5%) of these patients were randomised, with one excluded in the perioperative period. Forty-five (91.3%) of 49 recruited patients provided enough pain scores on a 4-point verbal rating scale to allow primary effectiveness outcome evaluation. Attrition rates were high; 18 patients supplied data at 6 month follow-up. Costs were dominated by length of hospital stay. Patients and healthcare professionals reported that trial processes were acceptable. CONCLUSIONS: Recruitment of patients into a trial comparing PNC use to usual care after major lower limb amputation with postoperative pain measured on a 4-point verbal rating scale is feasible. Evaluation of longer-term symptoms is difficult. TRIAL REGISTRATION NUMBER: ISRCTN: 85 710 690. EudraCT: 2016-003544-37.