Reply: The Split Pectoralis Flap
Similar to the authors, we agree with the initial treatment of sternal wounds with surgical débridement and negative-pressure therapy, allowing bacteria reduction, increased microcirculation, and wound bed preparation.1 As described, patients are initially treated by meticulous débridement, which often requires removal of necrotic tissue and sternal bone.2 We often use negative-pressure therapy after initial débridement and before definitive closure. However, in some cases, purulent mediastinitis requires daily monitoring and mechanical débridement. Evaluation of wounds is limited by negative-pressure therapy, as dressing changes occur less frequently and lack transparency to allow wound monitoring. Therefore, we do not rely on negative-pressure therapy alone before definitive closure.
We find the cranial and caudal approximation of flaps an interesting solution to the coverage of the distal sternum and xiphoid area. This solution delivers well-vascularized tissue to allow for coverage of the wound, which may require complete release of the pectoralis major muscle.3 Our technique allows coverage of the lower xiphoid and filling of mediastinal dead space resulting from débridement of necrotic tissue and bone, especially in obese patients. Furthermore, the cosmetic appearance and the function of the pectoralis major are maintained, by leaving the superior portion of the pectoralis attached to the humeral head.
We have found closure of the superficial planes to be challenging, especially in the xiphoid area in all sternal closures, as undermining laterally of fasciocutaneous flaps at the xiphoid does not yield significant advancement and can result in skin necrosis in this watershed area. However, we have not had difficulty of skin closure over the pectoralis turnover flap, as the area where the turnover contains its greatest bulk is between the nipple and inframammary fold where skin laxity is available.2 Similarly, elevating and undermining a fasciocutaneous flap for women with macromastia presents a challenge in disruption to the blood supply to the breast and can cause medial skin necrosis.
Our experiences have demonstrated that the benefit of well-vascularized tissue coverage of mediastinal dead space without the morbidity of an omentum flap outweighs the initial superficial bulky appearance, which decreases with time. Lastly, we have used negative pressure over the incisional closure of pectoralis flaps to reduce final closure tension with excellent results.