Efficacy of non-thermal gas plasma on sub-clinical wound infection (biofilm) in patients with diabetic ulcers

INTERVENTION: Participants are randomised to one of two groups using sealed, opaque sequentially numbered envelopes (SNOSE) Intervention group: Participants receive local standard of care wound dressing (SOCD) plus 5 minutes treatment of NTGP twice weekly over a period of 30 days (4 weeks). SOCD involves cleansing the wound with sterile water or normal saline and then dressed with the local standard of care dressing e.g. Aquacel Foam non‐adhesive, Aquacel Foam adhesive, Biatain foam non adhesive, Biatain Foam adhesive. NTGP involves a two minute treatment of argon gas plasma directly over the wound. Control group: Participants only receive local standard of care wound dressing (SOCD) twice weekly. This involves cleansing the wound with sterile water or normal saline and then dressed with the local standard of care dressing e.g. Aquacel Foam non‐adhesive, Aquacel Foam adhesive, Biatain foam non adhesive, Biatain Foam adhesive. Follow up for all study participants will occur after the 4 weeks, last samples and digital photographs will be taken at this time and participants will be informed when the results of the study will be completed and published. CONDITION: Chronic diabetic foot ulcers ; Circulatory System ; Chronic diabetic foot ulcers PRIMARY OUTCOME: Wound volume is measured using digital photographic imaging that will record, and measure the wound bed tissue type, wound dimensions and wound volume at baseline, 1, 2, 3 and 4 weeks. SECONDARY OUTCOME: 1. The effect of gas plasma in regards to accelerated healing is measured using wound tissue biopsy’s and wound slough samples taken from the 60 patients at baseline and week 4; 2. Presence of biofilms is measured as the numbers of bacteria and comparison to bacteria quantified from the wound surface, using wound tissue biopsy’s and wound slough samples, at baseline and week 4; 3. Microbial populations are measured using digital photographic imaging, at baseline week 1, week 2, week 3, week 4 as well as wound tissue biopsy and wound slough samples at baseline and week 4 INCLUSION CRITERIA: Inclusion criteria as of 04/04/2017: 1. Male or female, 2. Aged 18 years and over 3. Diabetics with HbA1c less than 10% (<86mm/mol) (Amended 12/09/2017 to Diabetics with HbA1c less than 12% (<108mm/mol)) that has been recorded within the previous 3 months 4. Foot ulcers with University of Texas grade/size A1or A2 or B1* sited below the ankle including plantar, dorsal and heel ulcers *Texas grade B1 ulcers which have symptoms consistent with mild diabetic foot infection (IDSA 2012)14 including: 4.1. Pus or inflammation 4.2. Inflammation extends less than 2cm from the wound 4.3. Infection is limited to skin/soft tissue 4.4. Systemically well 5. Ulcers with dimension 1.0cm2 – 30cm2 6. Ulcer where there is less than 40% decrease in wound surface area in the previous 4 weeks 7. Ulcer has not been present for more than 2 years 8. If foot pulses not palpable the toe brachial pressure index (TBPI) should be greater than 0.5 9