Prevena Incision Management

Study Overview
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Brief Summary
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The question this research project wants to explore is whether using the Prevena Incision Management System (Prevena) will improve sternal wound edge oxygenation in patients undergoing Coronary Artery bypass surgery with Bilateral Internal Mammary Artery grafts.

Detailed Description
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Coronary artery bypass is the gold standard surgical treatment of patients with complex coronary disease. It is a common operation and more than 16000 procedures per year are carried out in the UK. Recent publications suggest that during the bypass procedure both left and right internal mammary arteries should be used to bypass coronary stenoses. It was noted that using both internal mammary arteries will result in even better long term survival with improved freedom from cardiac events such as myocardial infarction or further coronary intervention than using. The major drawback of using both internal mammary arteries is the increased risk of sternal wound infection and breakdown. The investigators will use Near Infra-Red Spectroscopy (NIRS) to assess the wound edge oxygenation delivery. The NIRS INVOS system the investigators use within Sheffield Teaching Hospitals can measure oxygenation of soft tissue to a certain depth making it suitable for the assessment of wound edge oxygen delivery. Prevena is commercially available and has a CE mark. The Prevena wound management system differs from conventional wound dressings, it applies negative pressure to the closed wound for 7 days. Wound complications/infections are decreased when this type of wound management system is used. Studies suggest that Prevena achieves these outcomes because of an increase of perfusion in the wound edges and keeping the wound dry. Patients will be randomised to either the Prevena wound management or their standard of care NHS wound management for their procedure. The oxygenation and outcomes of the wounds will be compared through data collection and the patients followed up during their routine inpatient care and 6 week outpatient appointment.

Official Title
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Effect of the Prevena Incision Management System on Sternal Wound Edge Perfusion in Patients Undergoing CABG With Bilateral Mammary Artery Grafts

Conditions
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Cardiac Event, Arrest; Cardiac, Complicating Surgery, Coronary Bypass Graft Stenosis, Complication of Coronary Artery Bypass Graft

Intervention / Treatment
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* Device: Bilateral Internal Mammary Artery grafts
* Device: Prevena


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Eligible patients are those who require isolated coronary artery bypass surgery, who need at least 2 bypass grafts, and who are deemed suitable by the operating surgeon to have both right and left internal mammary arteries harvested as conduits Exclusion Criteria: Require additional procedures in addition to the coronary bypass or need for internal mammary artery harvest for feasibility study Who are deemed by the operating surgeon as unsuitable for bilateral internal mammary artery harvest because of Age (75 or older where prognostic benefit of using both internal mammary arteries has been questioned), Obesity with a BMI which is higher than 35 (increased risks of wound infection) Diabetes (of any type) (increased risks of infection.)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Bilateral Internal Mammary Artery grafts<br>Standard care wound dressings used as part of coronary artery bypass graft operation | Device: Bilateral Internal Mammary Artery grafts<br>* Sternal Wound Edge Oxygenation in patients undergoing Coronary Artery bypass surgery with Bilateral Internal Mammary Artery grafts<br>|
| Experimental: Prevena<br>Prevena dressing used as part of coronary artery bypass graft operation. | Device: Prevena<br>* The Prevena wound management system applies negative pressure to the closed wound for up to 7 days and is associated with lower rates of surgical site infection.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| NIRS measurement of the inferior third of the parasternal region and left forearm assessment | NIRS assessment of the left forearm will also be performed at the same time acting as a control to take into account factors other than wound perfusion that influence oxygen delivery. The difference of the two readings will be the final measurement used for comparison. | Measurements taken up to 6 weeks post sternotomy wound dressing | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Wounds will be scored according to the ASEPSIS scoring system | This will be done by an observer who is blinded to the dressing used. | On the day of dressing removal and at the 6 week postoperative outpatient visit. |