A Randomized Controlled Trial Exploring the Ability of Negative Pressure Wound Therapy (NPWT) to Reduce Colorectal Surgical Site Infections (SSI)

The trial will commence with recruitment of participants after an assessment of their potential eligibility. Those recruited in the trial will sign informed consent either on the day of surgery or during the PAC appointment, before any study-related activities are performed.

Perioperative measures will include bowel preparation with Fleet Phospho-soda, preoperative shaving with electric clippers 1 hour before the operation, and intravenous prophylactic antibiotic administered 30 minutes before the incision, and repeated in OR if the operation lasts more than 3 hours, and discontinued within 24 h after the operation. In all procedures, chlorhexidine solution will be applied to the skin to achieve preoperative skin antisepsis, and the usual reusable or disposable surgical gowns, drapes, and gloving will be used. The type of surgical procedure will be a colorectal resection for any malignant or benign condition of the colon, rectum or anal canal via a laparotomy wound. The type of incision will either be a vertical midline or transverse abdominal incision. Laparotomy wound will be closed primarily as a mass closure technique utilizing polydioxanone (PDS) or Nylon suture. Skin and subcutaneous tissues will be approximated using stainless-steel staples.

During the surgery, assessment of eligibility (including wound classification) will be completed, and if eligible, the participant will be randomized to one of the two treatment arms - group A (conventional dressing) or group B (Prevena dressing). The randomization scheme is described later in the protocol. After the surgical wound is closed, the assigned dressing - conventional dressing (Mepore) or Prevena dressing - will be applied.

For participants in group A (conventional dressing) the wound will be inspected on an as needed basis during postoperative days 1-6 to assess for SSI (where day 0 = day of surgery). On postoperative day 7, the dressing will be removed. If the participant is in hospital, the wound care nurse or study staff will remove the dressing and examine the wound for SSI. If the participant was discharged before postoperative day 7, the home care nurse or the participant's physician will remove the dressing. The patient will have been sent home with a Post-Op Day 7 follow-up form, and will have been instructed to provide the form to the home care nurse or their physician to complete for the assessment for SSI.

For participants randomized to group B (Prevena dressing), the wound care nurse or study staff will inspect the dressing daily during postoperative days 1-6 (where day 0 = day of surgery) to assess for proper functioning of the Prevena dressing. If the participant is discharged before postoperative day 7, the wound care nurse or study staff will contact the participant daily to check for proper functioning of the Prevena dressing. On postoperative day 7, the Prevena dressing will be removed. If the participant is in hospital, the wound care nurse or study staff (residents or Surgeons) will remove the dressing and assess the wound for SSI. If the participant was discharged before postoperative day 7, the home care nurse or the participant's physician will remove the dressing. The patient will have been sent home with a Post-Op Day 7 follow-up form, and will have been instructed to provide the form to the home care nurse or their physician to complete for signs of SSI.