NFC Dressing for Skin Graft Donor Sites
Condition: Skin Transplantation
Study type: Interventional

Summary: 
      The aim of this single center clinical investigation was to optimize nanofibrillar cellulose
      (NFC) wound dressing and to investigate final product FibDex in the treatment of split
      thickness skin graft donor sites. Performance of NFC dressings Type 1, Type 2, Type 3 and
      Type 4 (final product, FibDex) was compared with that of Suprathel®.
    

Detailed description: 
      The aim of this study was to investigate the suitability of FibDex for the treatment of skin
      graft donor sites. The study results will help to 1) ensure that the performance of the study
      product corresponds to product definition, 2) estimate the study product suitability for use
      and 3) determine the potentially emerging adverse effects of the study product.

      During the clinical investigation the study product has been in normal use, as defined by the
      manufacturer in the intended use. Those members of the study team who work at the study
      location gave their assessment on the suitability of the NFC dressing for treating the
      patients using their clinical assessment and experience.

      The NFC dressing was used during the study to protect the skin graft donor sites, and its
      effect on the skin graft donor site healing was compared to Suprathel® (PolyMedics
      Innovations GmbH, Germany). Suprathel® is the most commonly used skin graft donor site
      material for the treatment of large burns at the Helsinki Burn Centre. Suprathel® has similar
      indications and applications as the NFC dressing.

      The clinical study was performed according to the Clinical Investigation of medical devices
      for human subjects, good clinical practice (ISO 14155:2011) at Helsinki Burn Centre, Helsinki
      University Hospital, Finland. The study was approved by the Research Ethics Committee at the
      Helsinki University Hospital (99/13/03/02/2014 and HUS/1166/2016), and enrolled burn patients
      or patients requiring skin graft donor site treatment with exclusion criteria of pregnancy
      and age under 18 or over 75 years. Subjects or their legal representatives were informed of
      procedures and provided written informed consent. Altogether 24 patients were treated with
      FibDex, having a comparison to Suprathel® with 17 patients. It was hypothesized that, due to
      the inherent characteristics of NFC, treatment of donor sites with FibDex would expedite
      wound healing.

      A Zimmer® air dermatome (Zimmer Inc., USA) was used to harvest 6/1000 inch (0.15 mm)-12/1000
      inch (0.30 mm) thick split-thickness skin grafts. The separate donor sites were covered with
      FibDex or with FibDex and Suprathel® except in one patient whose single donor site was
      divided into two parts and treated with both dressings. Experimental dressings that were left
      in place for the entire treatment period were covered by Jelonet® (Smith & Nephew, UK) and
      fixed with staples. When compared to Suprathel®, anatomically equivalent areas were chosen
      for donor sites. The dressings were randomly selected for treatment of each donor site.

      The healing time of the donor site was determined as the self-detachment day of FibDex or
      Suprathel® + Jelonet® dressings. Both donor site materials behave similarly detaching from
      the wound bed when new epithelium is regenerated. Postoperatively, the experimental dressings
      on skin graft donor sites were checked by visual observation when changing the overlaying
      dressings at interval of a few days on average on postoperative days (POD) 4, 7, 10, 14, 20
      and 28, or when clinically relevant (±1-3 days), until self-detachment. During observations,
      skin quality, the epithelialization percentage of the donor site skin and the possible
      adverse effects were evaluated by a plastic surgeon. In addition, subjective pain experience
      was questioned from the patients using scale 0-10 (0 representing no pain and 10 the worst
      possible pain). Donor sites and wound dressings were photographed during the examinations
      throughout the clinical study period. Skin elasticity, viscoelasticity and TEWL were measured
      after discharge, one and six months postoperatively. In addition, scar quality was evaluated
      using the POSAS that was translated to Finnish but not validated in Finnish language. The
      POSAS consists of two numerical scales, the patient and the observer scar assessment scale
      that scores six parameters on a 10-point rating scale, in which the highest score represents
      the worst imaginable scar.

      Elasticity, viscoelasticity and TEWL were measured from patients' epithelialized skin treated
      with FibDex dressing or Suprathel® during follow up examination at one and six months after
      commencement of the treatments using DermaLab® Skinlab COMBO (Cortex Technology, Denmark),
      which is a reliable instrument for objective measurements of skin elasticity and TEWL. The
      elasticity of the skin was assessed in terms of elastic modulus and viscoelasticity. TEWL was
      expressed as g/m2/h to assess the epidermal barrier function. Transepidermal water loss
      increases when the skin barrier is damaged and is therefore an important parameter to
      evaluate the efficiency of the human skin barrier. For measurements, a single (in case of
      TEWL measurement) or 4-5 (in case of elasticity measurements) successive readings were taken
      at the same site. Control measurements were taken on healthy, not operated skin of the same
      subject at equal location.
    

Intervention name(s): FibDex wound dressing; NFC wound dressing Types 1-3; Suprathel (comparator)
Intervention type(s): Device; Device; Device
Intervention description(s): Treatment of donor sites of 24 patients with the dressing Type 4 (final product i.e. FibDex) until the self-detachment of the wound dressing i.e. epithelialization; Treatment of donor sites of 9 patients with the NFC dressing's (proto)Types 1-3 until the self-detachment of the wound dressing i.e. epithelialization; Treatment of donor sites of 22 patients with Suprathel dressing, which was used as a reference (comparator) product, until the self-detachment of the wound dressing i.e. epithelialization
Other intervention name(s): NFC wound dressing
Intervention model: Single Group Assignment
Intervention model description: Single center clinical investigation with patients selected by the clinicians. The donor sites were treated and compared intra-individually in the same patients.
Masking: None (Open Label)
Primary purpose: Treatment