Comparison of Prevena Negative Pressure Incision Management System vs. Standard Dressing After Vascular Surgery

Complications such as surgical site infections, deep wound infections, prosthetic graft
infections, and non-infections problems such as wound dehiscence continue to cause
significant morbidity for patients undergoing arterial reconstruction for peripheral arterial
disease. Patients undergoing leg bypass surgery for limb salvage are at particular risk due
to their medical problems such as diabetes and renal failure and location of incisions along
the groin area. Surgical site infections (SSI) are estimated to occur in 5-40% of patients
undergoing arterial bypass for lower extremity arterial occlusive disease. The in-hospital
SSI rate is 5% across the Vascular Study Group of New England, a regional quality improvement
registry. Factors contributing to wound infections include patient factors such as advanced
age and comorbidities such as obesity, diabetes and renal insufficiency and surgical factors
including the division of local lymphatics in the groin, placement of a prosthetic graft and
inherent difficulty in keeping an incision across the groin crease covered, dry and
protected.

Despite the use of standard sterile technique and perioperative preventative antibiotics
infections these complications continue to cause patient morbidity. In addition these
complications increase the intensity and cost of care with an added estimated expense of
$11,000 per incident. New strategies are needed to reduce these complications. Negative
pressure wound therapy has the potential to prevent a variety of wound complications. One
innovative strategy that has shown promise is the application of the Prevena dressing system
over the closed surgical incision. The dressing consists of a sterile sponge that is placed
over the incision followed by a plastic adhesive covering that is used to secure it to the
skin forming an air-tight seal. The sponge is then connected by tubing to a vacuum that
applies negative pressure to the closed system. This allows fluid to drain from the wound and
into a container connected to the dressing. When compared to surgical dressing with sterile
gauze and tape, the Prevena dressing system has the advantages of providing a sterile
barrier, reducing tension on the incision, and removing fluid from the incision. Please refer
to patient brochure for an illustration and further description of the Prevena dressing
system.

Negative pressure wound therapy has been applied for many years to enhance healing of a
variety of open wounds including pressure wounds, diabetic ulcers, venous stasis ulcers, open
infected surgical to traumatic wounds and burns with variable success. The treatment is based
on evenly distributed local negative pressure applied to the wound surface. The open wound is
filled with a sponge and covered with an occlusive dressing which is then connected by means
of a set of suction tubes to a device which applies negative pressure on the surface of the
wound that can be adjusted either cyclically or continuously. The fluid from the wound is
collected into a container. The benefits of negative pressure wound therapy have been
reported to include removal of infectious material, reduction in edema and improved perfusion
to tissue.

The success of negative pressure wound therapy with open wounds has been extrapolated to
intact surgical incisions. Recently a negative pressure wound therapy dressing has been
developed for use over closed surgical incisions.

The investigators aim to study the ability of a negative pressure wound therapy dressing to
prevent wound complications after vascular surgery involving incisions in the groin.

The aim of this study is to compare the Prevena dressing system to standard surgical dressing
in patients undergoing leg bypass surgery or femoral endarterectomy with or without patch
angioplasty involving the common femoral artery and/or profunda and/or proximal superficial
femoral artery. The index groin may have undergone prior procedures (may be inflow or outflow
for existing grafts), but the patient must have fully healed from the prior operation. May
include patients with concomitant proximal and/or distal peripheral vascular intervention.
The patch may be autogenous venous or arterial or prosthetic material such as bovine
pericardium, dacron or polytetrafluoroethylene (PTFE) as well as bilateral femoral
endartectomies are eligible for enrollment. The right and left groin incision would be
randomized to the same dressing which is consistent with routine clinical practice. for
vascular disease involving their legs in a multicenter randomized trial. All other aspects of
the procedure are the part of standard vascular surgery practice. Patients undergoing
vascular surgery with an incision in the groin will be treated with a standard gauze dressing
or the Prevena wound management system which will be applied in the operating room and left
on the wound for 5-7 days. Follow-up visits to assess the surgical wound are already standard
of care. The two groups will be compared based on the primary and secondary endpoints listed
in these documents. Quality of life will be compared by a patient survey and a cost analysis
will be performed.

Inclusion Criteria:

1. Age ≥ 18

2. Patient undergoing vascular surgery that would include a groin incision as a standard
part of the operation. Infrainguinal bypass including femoral popliteal/tibial/pedal
artery bypass with autogenous or prosthetic conduit.

3. femoral endarterectomy with or without patch angioplasty involving the common femoral
artery and/or profunda and/or proximal superficial artery. The index groin may have
undergone prior procedures (may be inflow or outflow for existing grafts), but the
patient must have fully healed from the prior operation. May include patients with
concomitant proximal and/or distal peripheral vascular intervention. The patch may be
autogenous venous or arterial or prosthetic material such as bovine pericardium,
dacron or polytetrafluoroethylene (PTFE). Bilateral femoral endarterectomies are
eligible for enrollment. The right and left groin incision would be randomized to the
same dressing which is consistent with routine clinical practice.

4. Willing to comply with protocol, attend follow-up appointments, complete all study
assessments, and provide written informed consent.

Exclusion Criteria:

1. Any groin incision on index leg within 12 weeks prior to treatment initiation.

2. Infrainguinal bypass without a groin incision including popliteal-tibial or pedal
bypass.

3. Supra inguinal procedures such as open or endovascular abdominal aortic aneurysm
repair or aorto-femoral/bi-femoral bypass for occlusive disease.

4. Undergoing current chemotherapy or radiation therapy.

5. Pregnancy or lactation.

6. Inability or refusal to provide informed consent.

7. Patients who received an investigational drug for peripheral arterial disease within 4
weeks of screening or who participated in another non-observational clinical trial in
the prior 30 days.

8. Surgical incision in the groin without primary closure including previously open or
infected wounds.

9. Sensitivity or allergy to silver.

10. Prior enrollment in this randomized controlled trial.