Chest and Abdominal Wall Reconstruction

THORACIC RECONSTRUCTION

What is the most common intrathoracic problem that requires intervention by a plastic surgeon?

Empyema (collection of pus within the pleural space). This can be secondary to problems such as bronchopleural fistula or esophageal perforation, and a thoracic surgeon may enlist the help of a plastic surgeon in managing these difficult problems.

What is a bronchopleural fistula, and what is the cause?

A bronchopleural fistula is a communication between a bronchus and the pleural cavity that is usually caused by postoperative necrosis of the bronchial stump following lung resection. A bronchopleural fistula can also result from necrotizing pneumonia or necrosis of the bronchial wall secondary to radiation.

What are the important principles in the successful management of an empyema resulting from a bronchopleural fistula or esophageal perforation?

1. Assessment and optimization of the patient’s overall medical condition and nutrition status.

2. Appropriate antibiotics based on culture and sensitivity data.

3. Resection and/or debridement of the bronchopleural fistula or esophageal perforation back to healthy tissue, and closure.

4. Obliteration of dead space and reinforcement of any bronchial or esophageal repairs with well-vascularized tissue. Typically a flap is required.

5. Adequate drainage after reconstruction.

How do you obliterate intrathoracic dead space?

Larger, bulkier muscle flaps (pectoralis major, latissimus dorsi) or omentum is used to fill the hemithorax. Often, an intercostal muscle flap is used to bolster a bronchial or esophageal repair, and a muscle flap can be transposed into the chest through the intercostal muscle flap donor site. Alternatively, a rib resection can be performed to allow transposition of the muscle into the chest.

What are the common acquired chest wall problems that require intervention by a plastic surgeon?

Chest wall defects resulting from tumor resection, trauma, or wounds resulting from radiation, severe infection, and surgical complications.

What are the important goals and principles in the successful management of these chest wall problems?

1. Resection of the tumor with adequate margins.

2. Debridement of all devitalized/damaged issue.

3. Optimization of respiratory mechanics by the creation of an airtight pleural space with a stable chest wall such that negative intrathoracic pressure can be generated during inspiration.

4. Protect intrathoracic organs and prevent problems such as lung hernia and diaphragmatic hernia.

5. Recruitment of well-vascularized soft-tissue coverage of the defect that will allow for adjuvant radiation therapy if indicated.

6. Re-establish a cosmetically acceptable chest wall contour.

Describe the differences between nonrigid, semirigid, and rigid reconstruction of the chest wall.

Nonrigid methods of reconstruction include soft-tissue flaps such as muscle and musculocutaneous flaps. While this method does recruit well-vascularized tissue, there is minimal contribution to the structural integrity of the chest wall. Paradoxical chest wall motion may be a significant problem to these patients postreconstruction.

Semirigid methods typically refer to a situation where mesh is used to span a skeletal defect, and the mesh is sutured in place under tension. Synthetic (polypropylene and polytetrafluoroethylene [PTFE]) or bioprosthetic mesh can be used depending on the clinical situation.

Rigid fixation involves the use of foreign bodies such as polymethylmethacrylate “sandwiched” between synthetic mesh such as polypropylene. Autologous forms of rigid fixation can include rib and fascia grafts, but these have largely been replaced by synthetic products. Absence of bacterial contamination, and well-vascularized, nonradiated soft-tissue coverage is critical when using foreign material for rigid fixation of the chest wall because infection will require removal of the construct with loss of the entire reconstruction.

When is rigid reconstruction of the chest wall indicated, and when is nonrigid reconstruction sufficient?

Universally accepted guidelines based on high-quality data do not exist, but various authors have provided the following guidelines:

Size-based criteria: chest wall defects larger than 5 cm, or defects involving 4 or more ribs should undergo rigid reconstruction.

Location-based criteria: chest wall defects involving the apex and posterior chest wall do not require rigid fixation, except when the tip of the scapula may become impacted in the defect. In this case, semirigid fixation should be considered. Anterior and lateral defect should be considered for rigid reconstruction.

What are the problems associated with rigid reconstruction of the chest wall?

Rigid fixation is associated with higher rates of surgical site infection. When infection occurs, reoperation and removal of foreign material are indicated, either acutely, or after a delay period to first allow for fibrosis. In either case, this may lead to a delay in any planned chemotherapy or radiation therapy. Rigid reconstruction may also result in more chronic pain. The risks and benefits of rigid fixation of the chest wall must be carefully considered for each individual patient.

How does radiation therapy impact reconstruction of the chest wall?

Radiation-induced fibrosis may result in enough stiffening of the chest wall to prevent paradoxical respiratory movement so that rigid reconstruction may be unnecessary. It is also prudent to avoid placement of a foreign body in a radiated field. Radiation therapy also mandates the use of well-vascularized healthy tissue for reconstruction.

What are the common flaps used for thoracic reconstruction?

The latissimus dorsi, pectoralis major, rectus abdominis, and serratus anterior muscles are commonly used. The omental flap also has several applications. Intercostal muscle flaps play a role in re-enforcement of bronchial, tracheal, and esophageal repairs. Free tissue transfers are less commonly used, but may be required.

What is the blood supply of the latissimus dorsi muscle?

The thoracodorsal artery, arising from the subscapular artery, is the primary blood supply of the latissimus dorsi muscle. The latissimus dorsi flap can also be based on posterior intercostal perforators and used as a turnover flap to address defects in the mid-back region. For thoracic surgery patients who have previously undergone a posterolateral thoracotomy, the latissimus dorsi muscle is often divided, making the distal portion of the muscle unusable for reconstruction unless a muscle-sparing thoracotomy was used.

What is the blood supply of the serratus anterior muscle?

The serratus branch off the thoracodorsal artery from the subscapular system supplies the serratus anterior muscle.

What is the blood supply of the pectoralis major muscle?

The pectoral branch of the thoracoacrominal artery is the primary blood supply of the pectoralis major muscle. The pectoralis major muscle can also be based on internal mammary artery (IMA) perforators and used as a turnover flap for sternal wound closure.

What is the blood supply of the rectus abdominis muscle?

Although the primary blood supply of the rectus abdominis muscle is the deep inferior epigastric artery, for chest wall reconstruction, this flap is typically based on the superior epigastric artery, originating from the IMA. In cases where the IMA has been divided, a rectus abdominis muscle flap can be raised based on intercostal and subcostal vessels. A previous subcostal incision, however, is a contraindication to a superiorly based rectus abdominis flap.

What is the blood supply of the greater omentum?

The right and left gastroepiploic arteries supply the greater omentum. The omental flap can be based on either the right or left gastroepiploic artery.

STERNAL RECONSTRUCTION

How frequently does dehiscence of median sternotomy wounds occur?

1% to 5% of median sternotomy wounds will dehisce.

What are the common sternal and mediastinal problems that require intervention by a plastic surgeon?

Infection: Postoperative complications such as poststernotomy infections and mediastinitis. In addition, the sternoclavicular joint may become infected from hematogenous seeding from a distant source.

Exposures: Major vessels, pericardium and its contents, vascular grafts, and other critical hardware such as ventricular assist devices may become exposed and require coverage.

What are some risk factors for sternal wound infection?

Diabetes, COPD, obesity, smoking, renal failure, peripheral vascular disease, IMA harvest (bilateral harvest is higher risk than unilateral harvest), prolonged hospital course, ICU course or ventilator support, and use of intra-aortic balloon pump.

What are the different presentations of sternal wound infections?