Surgical site infection is an infection at a place in the body where surgery has taken place, and has been reported in around 5% of people undergoing an operation. In vascular surgery, infection rates are as high as 30%. Methods to reduce this rate of infection should be investigated thoroughly for their effectiveness and cost-effectiveness.

The investigators aim to conduct a research trial examining one such method. Leukomed Sorbact is a wound dressing coated with a chemical (DACC) derived from spider-silk that interacts with, and binds bacteria, causing them to be mechanically removed from a wound when the dressing is changed. The trial aims to compare the effectiveness of this dressing to a standard, non-coated dressing, in the reduction of surgical site infection.

718 patients from a number of centres across the UK will be recruited to this study. Adult patients who are having a vascular surgery operation will be approached for entry into the trial. The trial will be explained to them, as well as an explanation that participation is voluntary and their operation or other aspects of their care will not be impacted in any way should participants not wish to participate.

Participants will be randomised by computer into one of two groups - one group whose wounds are dressed with Leukomed Sorbact, and the other whose wounds are dressed with a standard dressing. Patients will be followed up at 30 days post-operatively. At the follow up, their wounds will be inspected for infection, and participants will be asked to complete short questionnaires measuring quality of life. Quality of life will also be assessed at 3 months post surgery.

The trial will aim to answer a number of questions, with the primary question being does a DACC coated dressing applied after an operation reduce the risk of an infection at the surgery site? It will also ask whether this treatment is cost-effective and whether it promotes satisfactory healing and evaluate the overall carbon footprint impact of each intervention.

Studies Within a Trial will be conducted to validate a remote diagnostic measure for detecting surgical site infection using wound images and the Bluebelle Wound Healing Questionnaire, evaluate feasibility of novel hair removal methods such as epilation and waxing, carbon footprint modelling within randomised controlled trials.

Inclusion Criteria:

In order to be eligible for inclusion in the study the participants must meet the following criteria:

• Adults ≥18 yrs undergoing clean or clean-contaminated lower limb vascular surgery, with wounds closed by primary intention.
• Able to understand the Patient Information Sheet and supplementary materials and capable and willing to give informed consent and follow the protocol requirements (including attending all follow-up visits and completing written questionnaires).

Exclusion Criteria:

Patients will not be included in the study if they meet any of the following exclusion criteria:

• Patients on antibiotics for other conditions at the time of surgery or in the follow up period.
• Patients undergoing any procedure that does not include lower limb incisions.
• Allergies to any component of either the DACC-coated dressing or the control dressing.
• Inability to give informed consent due to incapacity (as defined by the MCA 2005)
• Aged under 18 years at the time of recruitment
• Use of investigational drug/device therapy within preceding 4 weeks that may interfere with this study.