The Mepilex Cesarean Delivery Trial / MEPIDEL

Surgical site infection (SSI) is one of the most common complications of cesarean delivery and can lead to added treatment, longer hospital stays, readmission, and additional procedures. Risk is higher in patients with obesity, diabetes, prolonged rupture of membranes, intraamniotic infection, or a prior cesarean delivery. Many of these risk factors are common in the patient population served by the study site, where SSI rates approaching 10% after cesarean delivery have been observed.

The postoperative dressing is a potentially modifiable part of surgical care. Standard cesarean dressings provide a physical barrier over the incision but have no antimicrobial properties and offer limited moisture or drainage control. Silver-containing dressings have been studied in several surgical fields because of the antimicrobial properties of ionic silver. However, silver dressings vary widely in design. A prior randomized trial of a silver nylon mesh dressing after cesarean delivery found no reduction in SSI compared with standard care. That dressing differs substantially from multilayer silver foam dressings with silicone adhesive, such as Mepilex Border Post-Op Ag, so its findings may not apply to foam-based products.

Mepilex Border Post-Op Ag is FDA-cleared and already used in routine clinical practice at the study institution, but prospective data on its performance after cesarean delivery are limited, particularly in higher-risk obstetric populations. Before broader use can be supported, it is important to confirm that wound outcomes are not worse than with the standard dressing. This study therefore uses a non-inferiority design. An increase in SSI of more than 5 percentage points was judged clinically unacceptable, based on clinical judgment, published cesarean SSI data, and expected baseline infection rates at the study site. If non-inferiority is shown, secondary analyses will examine whether the foam dressing offers additional benefit.

Patient experience is also an important part of postoperative recovery. Comfort, mobility, confidence in wound protection, and ease of dressing care may differ between dressings, so participant-reported satisfaction is collected alongside clinical wound outcomes.

Participants will receive a single Mepilex Border Post-Op Ag dressing applied over the cesarean incision immediately after skin closure in the operating room. The dressing is intended to remain in place until approximately postoperative day 7 (POD 7) unless earlier removal is clinically indicated or requested by the participant. If the dressing is removed early, it may be replaced at the treating physician's discretion.

Device: Mepilex Border Post-Op Ag

Participants will receive the institution's standard postoperative cesarean dressing, applied over the incision immediately after skin closure in the operating room. The dressing is typically removed on POD 1 or POD 2 according to routine institutional practice.

Device: Standard Postoperative Dressing

An FDA-cleared (510(k) K100029), self-adherent, silver-containing soft silicone foam dressing (Mölnlycke Health Care) indicated for postoperative wounds. Applied according to manufacturer labeling.

A sterile Telfa non-adherent pad (Cardinal Health) covered with sterile gauze and secured with a Primapore adhesive dressing (Smith \& Nephew). This is the institution's routine postoperative cesarean dressing.

Time frame: Up to 30 days after cesarean delivery

SSI will be defined by Centers for Disease Control and Prevention (CDC) criteria, including superficial incisional, deep incisional, and organ-space infections. SSI will be identified through provider documentation in the electronic medical record, outpatient wound evaluations, emergency department encounters, readmissions, antibiotic treatment for wound infection, wound drainage or debridement, reoperation, or participant report confirmed by clinical documentation. Data will be collected during hospitalization (POD 1-2), at the routine postoperative wound evaluation (POD 7-14, Mepilex Border Post-Op Ag arm only), and by medical record review and telephone follow-up (POD 30-40). All potential SSIs will be adjudicated by the PI or designee according to CDC criteria prior to final outcome classification. Participants with SSI occurring from cesarean delivery through POD 30 will be counted once, regardless of the number of episodes.

Time frame: Up to 30 days after cesarean delivery

Wound dehiscence will be defined as partial or complete separation of the cesarean incision documented by a clinical provider. Wound dehiscence data will be collected during hospitalization (POD 1-2), at the routine postoperative wound evaluation (POD 7-14, Mepilex Border Post-Op Ag arm only), and by medical record review and telephone follow-up (POD 30-40). Participants with wound dehiscence occurring from cesarean delivery through POD 30 will be counted once, regardless of the number of episodes.

Time frame: Up to 30 days after cesarean delivery

Wound seroma will be defined as a clinically documented localized collection of serous fluid at or beneath the incision. Wound seroma data will be collected during hospitalization (POD 1-2), at the routine postoperative wound evaluation (POD 7-14, Mepilex Border Post-Op Ag arm only), and by medical record review and telephone follow-up (POD 30-40). Participants with wound seroma occurring from cesarean delivery through POD 30 will be counted once, regardless of the number of episodes.

Time frame: Up to 30 days after cesarean delivery

Wound hematoma will be defined as a clinically documented collection of blood at or beneath the incision. Wound hematoma data will be collected during hospitalization (POD 1-2), at the routine postoperative wound evaluation (POD 7-14, Mepilex Border Post-Op Ag arm only), and by medical record review and telephone follow-up (POD 30-40). Participants with wound hematoma occurring from cesarean delivery through POD 30 will be counted once, regardless of the number of episodes.

Time frame: Up to 30 days after cesarean delivery

The number of participants with at least one emergency department (ED) or triage visit for a wound-related concern will be assessed. Data will be collected by medical record review and telephone follow-up (POD 30-40). Participants with at least one wound-related ED or triage visit occurring from cesarean delivery through POD 30 will be counted once, regardless of the number of visits.

Time frame: Up to 30 days after cesarean delivery

The number of participants with at least one unscheduled outpatient evaluation for a wound-related concern will be assessed. Data will be collected by medical record review and telephone follow-up (POD 30-40). Participants with at least one wound-related outpatient evaluation occurring from cesarean delivery through POD 30 will be counted once, regardless of the number of evaluations.

Time frame: Up to 30 days after cesarean delivery

The number of participants who were readmitted to the hospital for a wound-related concern or postoperative infection will be assessed. Data will be collected by medical record review and telephone follow-up (POD 30-40). Participants with at least one readmission occurring from cesarean delivery through POD 30 will be counted once, regardless of the number of readmissions.

Time frame: Up to 30 days after cesarean delivery

The number of participants who returned to the operating room for a wound-related complication will be assessed. Data will be collected by medical record review and telephone follow-up (POD 30-40). Participants with at least one reoperation occurring from cesarean delivery through POD 30 will be counted once, regardless of the number of reoperations.

Time frame: Up to 14 days after cesarean delivery; Postoperative day 1-2 (target Postoperative day 2) for the standard postoperative dressing arm; Postoperative day 7-14 (POD 7-14) for the Mepilex Border Post-Op Ag arm

Patient-reported dressing satisfaction will be assessed using the study-specific Dressing Satisfaction Questionnaire (DSQ). Items 1-8 of the DSQ are individually rated using a 5-point Likert scale ranging from 1 ("Strongly Disagree") to 5 ("Strongly Agree"). Item 7 (itching or discomfort) is reverse scored. A summary score will be calculated by summing Items 1-8, after reverse-scoring Item 7, yielding an overall possible score ranging from 8-40, with higher scores indicating greater overall dressing satisfaction. Participants whose dressing was removed early will answer based on the time it was in place. DSQ will be administered on postoperative day 1-2 (target day 2) for the standard dressing arm and on postoperative days 7-14 for the Mepilex Border Post-Op Ag arm.

Time frame: Up to 14 days after cesarean delivery; Postoperative Day 1-2 (target Postoperative day 2) for the standard postoperative dressing arm; Postoperative day 7-14 (POD 7-14) for the Mepilex Border Post-Op Ag arm

Patient-reported overall dressing satisfaction will be assessed using Item 9 of the DSQ. Item 9 assesses overall dressing satisfaction on a 0-10 scale rated from 0 ("Not at all satisfied") to 10 ("Extremely satisfied"), such that higher scores are indicative of greater overall satisfaction. Participants whose dressing was removed early will answer based on the time it was in place.

Time frame: Up to 7 days after cesarean delivery

The number of participants in the Mepilex Border Post-Op Ag arm with removal of the study dressing before the end of the intended wear period (POD 7) for any reason (e.g., participant request, discomfort, displacement, saturation, concern for infection, skin reaction, provider preference, or other clinical indication) will be assessed. Data will be collected by medical record review during hospitalization (POD 1-2) and at the routine postoperative wound evaluation (POD 7-14). Participants with premature removal occurring from cesarean delivery through POD 7 will be counted once, regardless of the number of removals or dressing replacements. This outcome will be reported for the Mepilex Border Post-Op Ag arm only, because the standard dressing is routinely removed on POD 1-2.

Time frame: Through study completion, up to 40 days after cesarean delivery

The number of participants with at least one adverse event attributed to the postoperative dressing (e.g., skin irritation, rash, blistering, contact dermatitis, allergic reaction, discomfort, wound maceration, or other provider-documented dressing-related concern) will be assessed. Dressing displacement and premature removal are dressing-performance outcomes and are not adverse events in isolation; an associated clinically significant event (e.g., skin injury, allergic reaction, or wound complication) will be evaluated as an adverse event. Data will be collected through inpatient documentation, the routine postoperative wound evaluation, participant report, telephone follow-up, and medical record review. Attribution to the dressing will be determined by the PI or designee. Participants with at least one dressing-related adverse event occurring from randomization through completion of follow-up will be counted once, regardless of the number of events.

A Randomized Controlled Non-Inferiority Trial of Mepilex Border Post-Op Ag Versus Standard Postoperative Dressing Following Cesarean Delivery