Method of Securing Skin Graft: A Comparison of Vacuum Assisted Closure Device Versus Bolster Dressing
Condition: Skin Graft Detachment
Study type: Interventional

Summary: 
      The goal of this randomized controlled trial is to compare the outcomes of vacuum assisted
      closure device versus conventional bolster dressing in securing split thickness skin graft in
      traumatic wounds; with emphasis on percentage of graft take and postoperative complications
      like hematoma, seroma and infection of graft site. Two groups were formed with 70 patients in
      each group. Patients were randomly allocated either to group A(VAC group) or group B(bolster
      dressing group) and outcomes were assessed on 5th post-operative day when first dressing
      change was done
    

Detailed description: 
      This randomized controlled trial was conducted at the Department of Plastic and
      Reconstructive Surgery at Dr. Ruth K.M. Pfau Civil Hospital Karachi from 21st October 2021 to
      20th June 2022. Before conducting the study, ethical approval was obtained from Dow
      University of Health Sciences (DUHS) (IRB-2125/DUHS/Approval/2021/637).

      All patients were enrolled via non-probability consecutive sampling. The sample size for the
      current study was calculated as follows:

      Mean graft take for VAC group = 96 ±6 Mean graft take for conventionally treated group =
      89±20 (10) Level of confidence = 95% Power = 80% A sample of 140 patients (70 per group) was
      required to detect mean difference of 7 in graft take between two groups as estimated by
      using the above parameters through online available calculator Open Epi.

      Patients visiting outpatient department and requiring skin graft were admitted to Plastic
      surgery and recruited into the study with their consent. Study purpose and risk and benefits
      associated with the procedure were explained to the patient to obtain their consent. Total 70
      patients in each group, meeting the inclusion criteria were enrolled. Patients were randomly
      allocated either to the conventional group or new technique group. Random allocation of
      patients was done using the SNOSE (sequentially numbered opaque sealed envelope) protocol.
      Total 140 sequentially numbered opaque sealed envelopes was prepared enclosing the group name
      with half of the envelop will be enclosing name of group A (VAC group) and other half
      enclosing the group b (bolster dressing group) and after that envelops was shuffled to ensure
      randomization.

      Skin grafting was performed under general anesthesia. Humby's knife was used to harvest skin
      graft from donor site. Skin graft was hand meshed and secured to the recipient site
      circumferentially with absorbable sutures, followed by Tincture of benzoin soaked paraffin
      gauze layer. For the bolster dressing group, the recipient site was bolstered with wet bulky
      cotton gauze dressing and wrapped with cotton bandage. 0.9% normal saline was used for
      moisture. For the Vacuum assisted closure (VAC) Group, two sheets of sterilized VAC sponge
      that was cut to fit the wound contour were placed with a fenestrated tube between the two
      layers that was secured to the surrounding skin using tincture of benzoin spray and an
      adhesive dressing (OPSITE). The VAC was placed at -125mmHg suction and checked for any air
      leak. Any loss of suction was treated by reinforcing the adhesive dressing over the air leak.
      The VAC was decompressed and clamped till the patient is shifted back to the ward. Once in
      ward, The VAC was placed to intermittent -125 mmHg suction for 2 hours and then decompressed
      for next 2 hours. Bed rest, sling or splint was used for immobilization depending on the
      location of injury.

      Patients were permitted for slight movement for personal hygiene reasons. First dressing
      change was done on 5th post-operative day. They underwent early change of dressing in case
      excessive soakage of dressing with blood, serous fluid or foul smelling discharge or pus was
      present. Dressing of patient was opened on 5th operative day by researcher and then assessed
      by supervising consultant for percentage of skin graft take and post-operative complications.
      A pre-designed proforma was designed to collect the data. Patients' data was kept
      confidential. Medical record no. of patients was tagged with other serial number to assure
      the confidentiality of the data and only principal investigator had an access to original
      data.

      Data was entered and analyzed by using SPSS version 21. Qualitative variables like gender,
      socioeconomic status, place of residence, smoking status, medical comorbidities (such as
      diabetes mellitus and hypertension), graft site, donor site, post-operative complications
      were presented as frequency with percentages. Quantitative variables such as age, height,
      weight, BMI, graft size, length of stay in the hospital, percentage of graft take were
      summarized in terms of mean standard deviation. Effect-modifiers such as age, gender, BMI,
      smoking status, graft site, graft size, diabetes and hypertension will be controlled through
      stratification. Post-stratification independent t-test or Mann Whitney U test will be applied
      to compare percentage of graft take among two treatment groups. Post-stratification
      chi-square test will be applied to assess difference of post-operative complications among
      two treatment groups. P-value <0.05 was considered as statistically significant.
    

Intervention name(s): VAC and bolster dressing
Intervention type(s): Other
Intervention description(s): Bolster dressing- Moist bulky cotton gauze dressing and wrapped with cotton bandage.
Vacuum assisted closure (VAC) dressing- A fenestrated tube placed between two sheets of sterilized foam secured to the surrounding skin using adhesive dressing (OPSITE).
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: A two arm parallel assignment, where group A will be VAC group and group B will be bolster dressing group.
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: Graft take, vacuum assisted, Bolster dressing