The acute surgical management of BPF depends not only on the etiology but also on the clinical presentation. In general, the main tenets of therapy are treatment of systemic infection, if present; drainage of infected fluid, if present; reexpansion of the lung; and treatment of the underlying cause, if at all possible. Specific management is discussed according to etiology.
Nonresectional Benign BPF
The most common nonresectional etiology for BPF is infection. BPF may be a complicating factor in necrotizing pneumonia or a lung abscess that ruptures into the pleural cavity. While bacterial infections are now more common, nonbacterial infections, such as Aspergillus or Mycobacterium tuberculosis, also have been reported to cause BPF. Clues to the development of a lung abscess with possible BPF include a nonresolving pneumonia that is refractory to antibiotics, fever, weight loss, and failure to thrive.1 Clinical presentation may range from a cough that is productive of infected sputum to frank sepsis from empyema. A pneumothorax may be present as well. Initial management relies on good drainage of the pleural space with a chest tube, broad-spectrum antibiotics to treat the underlying infection, and chest physiotherapy to aid drainage. Culture of the drainage fluid permits identification of the offending organism and specific treatment. Rarely, pulmonary resection is required. It should be noted that pulmonary resection for inflammatory diseases does carry a higher incidence of postresectional BPF.
Malignant BPFs generally are the result of necrosis of large tumors. These may be primary lung carcinomas or metastatic cancers such as sarcomas. Patients may experience shortness of breath as a result of a pneumothorax or possibly even tension pneumothorax. Management includes insertion of a chest tube to treat the pneumothorax. Depending on the stage and location of the tumor, resection may be an option, but usually malignant BPFs signal advanced disease. In patients with advanced disease, pleurodesis is sometimes effective.
Both penetrating and blunt chest trauma may result in a BPF. Laceration of pulmonary parenchyma and sublobar bronchi often can be managed by chest tube drainage alone. Failure to reexpand the lung after insertion of multiple chest tubes is an indication for surgery. Injury to the lobar or main stem bronchi may necessitate thoracotomy with primary repair or pulmonary resection in some cases.
BPFs also may result after radiation therapy, rupture of bullae, or in patients who are mechanically ventilated for acute respiratory distress syndrome. Again, in these situations, chest tube insertion generally is required if a pneumothorax exists. In patients with bullous disease, a limited pulmonary wedge resection or “bullectomy” may be indicated in those whose pneumothorax is refractory to chest tube management. In patients on mechanical ventilation for acute respiratory distress syndrome, a number of treatment options have been suggested, including jet ventilation and conventional ventilatory settings.2
Postresectional Benign BPF
With improved surgical technique and understanding of bronchial healing, the incidence of BPF after pulmonary resection has decreased dramatically over the past several decades.3 The incidence of BPF ranges from 1.5% to 11.1% after pneumonectomy and 1.5–2% after lobectomy. Mortality from BPF has been reported to range from 25% to 71% in the literature.
Through univariate and multivariate analyses, several variables have been identified that increase the risk of developing BPF. These include age, previous chemotherapy and radiation, postoperative mechanical ventilation, pneumonectomy, and right-sided procedures. Algar and colleagues4 studied 242 patients who underwent pneumonectomy for lung cancer. The incidence of BPF was 5.4%. Univariate analysis identified chronic obstructive pulmonary disease, hyperglycemia, hypoalbuminemia, previous steroid use, poor predicted postoperative forced expiratory volume in 1 second (FEV1), long bronchial stumps, and mechanical ventilation as risk factors. Multiple logistic regression modeling identified bronchial stump coverage and length, side, predicted postoperative FEV1, chronic obstructive pulmonary disease, and mechanical ventilation as variables affecting the development of BPF.
In a study of 767 patients undergoing lobectomy, 12 (1.6%) developed BPF. Five of twelve (41.7%) died as a result of the BPF. Multivariate analysis identified squamous cell carcinoma, preoperative chemotherapy, lower lobectomy, and middle/lower lobectomy as risk factors for BPF.5
The clinical presentation of a patient with a postresectional BPF may range from asymptomatic to subtle symptoms of dry cough or failure to thrive to fulminant sepsis from empyema. BPFs occur most commonly 8–12 days postoperatively,6 although they can be apparent by the first or second postoperative day to several years later.7
After pneumonectomy, the pleural space will fill with fluid. A decrease in the fluid level in the postoperative period should raise suspicion for a BPF. Some patients will complain of a dry, nonproductive, persistent cough resulting from irritation of the bronchial mucosa by the pleural space fluid. Development of pulmonary consolidation and infiltrate on the contralateral side consistent with aspiration also should raise suspicion of a BPF. Symptoms of failure to thrive (e.g., malaise, weight loss, and decreased energy) may be the only complaints of a patient with a BPF. Finally, signs and symptoms of sepsis owing to empyema also may be present in a patient with BPF.
In a patient with suspected BPF after pneumonectomy, the first step is to rule out empyema by thoracentesis under sterile conditions. Patient positioning is crucial to avoid contamination of the “good” lung. The patient should be sitting up or lying with the postpneumonectomy space down. If a stat Gram stain on the pleural fluid is positive or the fluid is grossly suspicious for infection, a chest tube should be inserted immediately to drain the postpneumonectomy space. Broad-spectrum antibiotics should be started until culture and sensitivity results are available.
The patient then should be taken to the OR, where a bronchoscopy may be performed. The bronchial stump should be examined for good apposition of the cartilaginous and membranous walls. A defect may or may not be visible. The length of the bronchial stump also should be noted. If a defect is not identified, there are several maneuvers that can help to identify a fistula. First, saline can be inserted, submerging the staple or suture line. Then air can be inserted via the chest tube in the pleural space and the staple or suture line observed for air bubbling. Others have described instillation of methylene blue through the bronchoscopy and detection in the chest tube, indicating a BPF.
CT scanning may have a role in the diagnosis and certainly in the evaluation of a peripheral BPF.8 A ventilation/perfusion scan also may be a helpful noninvasive test, especially in a patient with subacute presentation of failure to thrive.
The choice of management depends on the timing and presentation. A BPF diagnosed within the first 48 hours following lobectomy or pneumonectomy is caused by a technical error. The bronchial stump generally should be revised unless very small and amenable to endoscopic treatment. Endoscopic treatment with the use of fibrin glue, cyanoacrylate glue, cellulose, Gelfoam, silver nitrate, and coils has been reported with varying degrees of success. Stents also have been used with some success. For BPF diagnosed beyond 48 hours, traditional teaching has advocated drainage alone. Once the pleural space infection has resolved, the bronchial stump should heal. Wright and colleagues have suggested that all BPFs occurring within 1 month with minimal pleural contamination should be revised.3 Most would recommend buttress of the stump with pericardium, thymic fat pad, omentum, or muscle flap. The use of omentum is thought to enhance vascularity and provide fibroblasts to aid in healing. Other options include thoracoplasty and Clagett window. These procedures are discussed in Chapter 72.