The impact of smoking on absolute toe pressures in patients with active foot ulcers

Toe systolic pressures will be assessed by a podiatrist on patients attending Blacktown High Risk Foot Service. Patients will be asked when their last cigarette was and measures of toe pressures recorded. We will then ask them not to smoke 12 hours prior to their next appointment (usual treatment time for foot ulcers, 1-2 weeks) and toe pressures will be measured again. This will allow us to assess if there is any difference between toe pressures when a patient has smoked within the last 12 hours or not. We will be able to assess whether this has a direct impact on microcirculation and in turn, healing of foot ulceration This will all be done during their regular appointments to Blacktown High Risk Foot Service. The appointments are usually of 30-60 minute duration each (depending on the extent of their foot ulceration) and will involve measurement of bilateral toe systolic pressures which takes approximately 5 minutes in total to complete plus a smoking history questionnaire which will also take 5 minutes to complete at the beginning of each appointment. There will need to be two of these appointments for the purpose of the study, although all their usual care is provided during this time. Participants will be monitored for 2 years post-enrolment for any changes in ulcers, arterial disease or lower limb amputations. This data will be collected from medical records without active participation required.