Pilot study to test the clinical efficacy of FlowOx™ home treatment compared to standard care in patients with critical limb ischemia and lower limb ulcers

Introduction: Case study data on the effects of intermittent negative pressure (INP) therapy have shown improved haemodynamic outcomes; ulcer healing and reduced rest pain in patients with peripheral arterial disease (PAD). This pilot study will test the effects INP home treatment (trade name FlowOx™) on lower limb chronic ulcers in patients with critical limb inschaemia (CLI) compared to standard clinical care (SCC). Objective outcome measures will include:  ulcer healing rates; effective (and pragmatic) INP doses; quality of life outcomes and health economics data. Subjective opinions of the treatment and device will be sought via patient and clinician focus group discussions. 

Methods and analysis: This multicentre randomised controlled trial will recruit 15 participants with CLI and tissue loss from NHS vascular clinics in the Northwest region of the UK. Specifically, patients where surgical and pharmacological interventions have failed will be invited to take part. Strict inclusion and exclusion criteria will be used (and presented at the meeting). Participants will be randomised 2:1 to the intervention group (FlowOx™ home treatment) and the control group (SCC), respectively. The primary outcome is change in ulcer size after 3 months of treatment. Secondary outcome measures (at 1, 2 and 3 months) include: ABPI; TBPI;  ulcer size; rest pain; amputation incidence; VascuQol; EQ-5D-5L; PSQI; adherence to treatment; QUEST; comfort; ICECAP. A cost-effectiveness analysis of the FlowOx™ treatment versus SCC will be carried out from the perspective of health services. Focus group data will be collected after clinical data collection is complete. Thematic analysis will be conducted to gain understanding of clinician opinions and patient opinions and experiences of the FlowOx™ treatment.

Ethical approval has been obtained from the South Central – Oxford C Research Ethics Committee (17/SC/0089)
Trial registration number: ISRCTN51433523

Presented by:
Professor Chris Nester
Research Programme Leader |  School of Health Sciences PO 32, Brian Blatchford Building, University of Salford, Salford  M6 6PU