Which infection-prevention strategies reduce mediastinitis after CABG?

• A. Strict glycemic control, timely antibiotic prophylaxis, meticulous sterile technique, proper sternal closure, and diligent wound care.
• B. Rely solely on postoperative antibiotics; no glycemic control needed.
• C. Avoid prophylactic antibiotics to prevent resistance.
• D. Sterile technique is unnecessary.

Answer: (A)

Preventing mediastinitis after CABG relies on a bundled, multi-faceted approach that starts with how the patient is managed before, during, and after the operation. Each element targets a different aspect of infection risk, and together they provide the strongest protection.

Strict glycemic control matters because high blood glucose impairs immune cell function and collagen synthesis, slows wound healing, and increases susceptibility to infection. Keeping blood glucose levels in a near-normal range around the time of surgery reduces the likelihood that bacteria can take hold in the sternotomy site and promotes better healing of the sternal wound.

Timely antibiotic prophylaxis reduces the initial bacterial load at the operative field. Administering the right antibiotic before incision and ensuring proper dosing and timing (with redosing during longer surgeries as needed) helps prevent bacterial contamination from becoming an established infection in the mediastinal space.

Meticulous sterile technique during the operation minimizes the chance that skin or environmental bacteria contaminate the wound. This includes proper skin preparation, draping, instrument handling, and adherence to aseptic protocols throughout the procedure.

Proper sternal closure contributes to reducing infection risk by ensuring stable fixation and minimizing dead space or micromotion that can harbor bacteria or impair healing. Adequate closure helps prevent wound dehiscence and mediastinal contamination.

Diligent postoperative wound care continues the infection-prevention effort after surgery. Sterile dressing changes, careful monitoring for early signs of infection, and prompt management of any wound issues help prevent progression to mediastinitis.

The other approaches fall short because relying on antibiotics alone without addressing glycemic control or sterile technique, or ignoring prophylaxis entirely, does not sufficiently reduce risk. A comprehensive, evidence-based bundle like this tackles multiple pathways by which mediastinitis can develop, making it the most effective strategy.