Results of directly applied activated carbon cloth in chronic wounds: a preliminary study

Activated carbon (AC) has been used in wound therapy as an active substance inside dressings. Applying AC directly on a wound is a new concept. The aim of this study was to analyse the outcomes of chronic wounds which were managed with directly applied activated carbon knitted cloth (ACC, Zorflex) in Swiss patients.

A retrospective analysis of the records of all patients with chronic wounds treated with ACC between 1 October 2013 and 31 December 2015 in an outpatient wound clinic. Chronic was defined as a wound being present for >3 weeks. Malignant wounds were excluded. The main outcome was the time to complete closure or readiness for spilt-thickness skin grafting (STSG). Descriptive data, including nutritional status and angiology results were obtained.

There were 36 women and 34 men, median age 68 years old. The median body mass index (BMI) 28.1kg/m² and 76% (n=53) of patients had comorbidities. Angiology exam results showed signs of reduced arterial perfusion in 13% (n=9) of patients and malnutrition in 11% (n=8). Of the wounds included 34% (n=24) were on the trunk and 66% (n=46) on the extremities. The median wound size was 6.9cm² (range: 0.1-300cm²). The wounds on the trunk were larger than wounds on extremities (10 versus 2cm²). Overall, median time to wound closure was 51 days. In 94% (n=66) of patients, wounds closed without further intervention and 6% (n=4) underwent STSG. Patients with comorbidities showed longer wound healing times compared with those without. No adverse events such as allergies or skin irritation occurred. Cost analysis, including personnel and material and stratified according known wound closure times, showed ACC (US$ 1252) to be like hydrocolloids (US$ 1128), but substantially lower than white gauze (US$ 3026) and negative pressure wound therapy (NPWT) (US$ 2578).

ACC applied directly on chronic wounds of different aetiology is safe with short closure times. The cost efficiency is high. It combines the positive features of other wound dressings, such as hydrocolloids and NPWT, without their disadvantages. The dressing change of ACC is easy and non-specialised nurses or even patients themselves can be taught to perform it.