The Use of Wound Protectors to Prevent Surgical Site Infection for Whipples (Pancreatoduodenectomy) With Intrabiliary Stents: A Randomized Controlled Trial.

Introduction

The Department of Surgery at the University of Calgary has a long and proud tradition of research surrounding surgical site infections (SSI). More specifically, former surgeon and Department Chair Dr. Peter Cruse prospectively studied 23,649 surgical wounds following operative intervention. This massive study remains unmatched in size by a single institution publication. Dr. Cruse and Ms. Rosemary Foord demonstrated a decrease in SSI rates with the pre-surgical use of hexachlorophene wash and by not shaving the surgical site1. They observed an increase in SSI rates with advanced age, use of drains, prolonged hospital stay before the operation, and longer operative times. Dr. Cruse is directly responsible for confirming the validity of the wound classification system currently in use throughout the world (clean, clean-contaminated, contaminated, and dirty). We propose to carry on the tradition of this line of investigation, reinforcing Calgary as a world leader in SSI research.

SSI are a frequent and costly source of post-operative morbidity. They are the most common complication following gastrointestinal and biliary tract surgery, occurring in 5-30% of patients. SSI are associated with a two-fold increased risk of in-hospital mortality, a 50% increase in intensive care admission, a 6-day mean increase in hospital stay, and a five-fold increased rate of readmission. SSI also have additional and highly negative consequences in the treatment of oncology patients. More specifically, medical oncologists wait until all operative wounds are entirely healed prior to beginning adjuvant chemotherapy. This delay is both oncologically concerning, as well as psychologically destructive to highly stressed patients with poor associated survivals. Furthermore, with a significant SSI, this delay often leads to a total omission of adjuvant therapies as a whole. The estimated increased cost per SSI ranges from $1,300 to $5,000 in the United States. In Canada, a 1998 study estimated $3,937 per infection, resulting from increased hospital stay, as well as emergency department and clinic visits. The implications of these costs have now become paramount given that both U.S. Medicare and Medicaid currently deny any reimbursement for patients who obtain an SSI while admitted to hospital. In addition, patients who develop SSI experience psychosocial distress, loss of income, and loss of productivity. Prevention of SSI is therefore a vitally important goal in delivering quality care to patients. The SSI rate is 40-50% in patients undergoing pancreatoduodenectomy with intrabiliary stents, the population of interest for this study.

Wound protectors are devices designed to protect the abdominal wound tissue edges from contamination and trauma during laparotomy. A major reason for their conception and use is a theoretical reduction in risk of SSI. Various devices with similar intent have been described since the 1960s, falling into two main design categories: (1) Those with an internal and external ring connected by impervious plastic, and (2) Those with a single, internal ring connected to a drape which extends outward, over the wound edges and onto the abdomen where they are affixed with adhesive or clips.A recent meta-analysis of randomized controlled trials was conducted by a team led by the Principal Investigator to evaluate whether impervious plastic wound protectors reduce the risk of surgical site infection following gastrointestinal and biliary surgery. Six studies representing 1,008 patients were included. Wound protectors were associated with a 45% decrease in SSI (p = 0.04). The Alexis Wound Protector, a ring based model, had evidence of superiority to other products and has been selected for this study based on this finding.

Methods