The bony thorax with its overlying muscles and integument creates a cage that protects the relatively fragile heart, great vessels, lungs, esophagus, and large lymphatics. Disruption of the thorax by trauma, tumor, congenital anomaly, infection, or surgical intervention can have potentially lethal consequences. Advances in cardiac and thoracic surgery have enabled surgeons to operate safely within these cavities. Positive pressure ventilation with the use of selective tubes and bronchial blockers permits surgeons to open the pleural spaces and continue respiration while the pleural cavity is disrupted. Advances in cardiac surgery include cardiopulmonary bypass, intra-aortic balloon pumps, and ventricular assist devices that permit continued or augmented perfusion with oxygenated blood. These advances combined with a better understanding of biomaterials,^1–3 tissue-engineered solutions, and advances in plastic and reconstructive surgery^4–6 have allowed more complex sternal and chest wall defects to be successfully reconstructed. In this chapter we will focus our efforts on the multidisciplinary approach to reconstruction of the chest and highlight the three most common flaps used for large defects: the latissimus dorsi, pectoralis major, and omental flaps.

The chest wall has a robust blood supply provided anteriorly by the internal mammary vessels that arise from the subclavian artery and are connected via intercostals to the aorta. Multiple other arteries including the thoracoacromial trunk, transverse cervical artery, and the thoracodorsal artery provide the blood supply to muscles around the upper chest, back, and shoulders. A thorough understanding of the intricacies of the chest wall vasculature, including angiosomes, will allow the surgeon to design reliable flap coverage for most defects. Occasionally, if regional flaps are insufficient or unavailable, free tissue transfer may be necessary to close selected defects.

Large chest wall defects may benefit from a stable reconstruction of the ribs or rib cartilages to maintain adequate pulmonary function (see also Chapter 137). This is generally performed with a variety of materials including synthetic and biological implants. An understanding of the biomaterial/tissue interface is critical to the proper planning of any reconstructive operation. In addition, the stiffness of the biomaterial should optimally match that of the region being replaced to avoid stress concentrations at the junction between the biomaterial and normal tissue.

Meticulous surgical technique is essential in dissecting flaps and allowing them to survive when transferred. Because of the robust blood supply to the chest skin, many wounds can be closed with moderate tension without breakdown. Many chest wall reconstructive procedures occur before or after radiation therapy. Radiated tissues can be difficult to work with because of increased stiffness and their susceptibility to infection.

Patient Selection

The reconstructive surgeon must carefully match the many possible solutions of a thoracic defect to the needs of the specific patient. Chest wall compliance is a function of age, with older patients developing stiffer costochondral junctions and barrel chests. These patients often can tolerate more options for chest wall reconstruction than a younger patient where movement can result in chest wall instability. Younger patients require careful attention to the donor site and ultimate functional and aesthetic outcome and can tolerate longer, more complicated procedures to achieve these goals. Older, more debilitated patients are better served with a more expeditious and reliable operation that might involve more visible scarring. Chest wall reconstruction is optimally performed in a multidisciplinary setting that often includes reconstructive, thoracic, and cardiac surgery, as well as an experienced anesthesia team. A team that works together often will soon develop a sense for what operations can be safely performed in which patients.

Preoperative Assessment

The reconstructive surgeon needs to evaluate these patients in conjunction with a cardiac or thoracic surgeon to coordinate each portion of the procedure. The nutritional status of the patient as defined by albumin and prealbumin levels can be an important predictor of the ability to heal wounds and achieve a successful closure.⁷ A careful history and examination of the patients with regard to previous surgeries is essential to understand which flaps may not be usable based on previous incisions. Flaps ideally should come from areas that have not been heavily irradiated, so an assessment of where radiation therapy has been given is important. Also, many cancer patients may be on chemotherapy, and operative timing should be coordinated so an operation is not required when the patient is neutropenic.

The majority of thoracic reconstructions can be accomplished with one or a combination of the latissimus dorsi, pectoralis major, and omental flaps. Flaps have an independent blood supply and can be transposed into the defect. They fill dead spaces and allow a three-dimensional vascularized surface to deliver antibiotics, heal tissue, and help prevent direct cutaneous exposure of implanted biomaterials in the event of wound separation.

Latissimus Dorsi Muscle Flap

The latissimus dorsi muscle is the largest muscle in the body. It originates from the thoracic spine and thoracolumbar fascia to the iliac crest and inserts into the humerus (Fig. 138-1). Its major blood supply comes off the thoracodorsal system. The muscle can be accessed through a vertical, horizontal, or oblique incision or endoscopically.⁸ The skin and subcutaneous tissues are dissected off the muscle, and the muscle is then dissected off the chest wall. Large perforators off the paraspinous area and thoracolumbar area can be divided with clips or ties. The thoracodorsal pedicle is identified and preserved. The nerve can be left intact, divided, or crushed depending on the desired function of the muscle. For additional pedicle flap reach, the insertion to the humerus can be divided. If the insertion is divided, care must be taken to avoid tension on the pedicle. Suturing the tendinous insertion to the chest wall at a location that provides protection from tension to the pedicle should suffice and also will avoid rotational kinking that can occur if the flap is dissected to the point that it is only attached to the neurovascular bundle. This large muscle reaches nicely into the chest cavity after removing a portion of the second rib and easily covers the hilum. It also can easily reach the anterior mediastinum to cover the heart. With a skin paddle included with the tissue, it can be a useful flap for breast reconstruction or chest wall reconstruction. The distal portion of the flap can sometimes be unreliable because of vascular insufficiency, and caution therefore needs to be taken when the flap is used for defects that are distal to the costal margin. Although loss of latissimus dorsi function results in negligible functional deficit, a split-latissimus dorsi flap can be used to preserve some of its form and function. For many patients who have undergone a standard posterolateral thoracotomy, this muscle is divided and only the superior portion can be used based on the thoracodorsal blood system. The inferior portion can be used for lower thoracic defects based on perforators near the spine. Closure of this defect is generally accomplished with deep dissolvable sutures. Quilting sutures are preferred by many surgeons to reduce the size of the cavity, thus minimizing the risk of postoperative seroma, which has been reported to occur in 20% to 80% of patients.