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Numerous benign, infectious, and malignant diseases lead to recurrent pleural effusions. Patients with cancer often develop current malignant pleural effusions secondary to their underlying disease. These malignant pleural effusions (MPE) frequently cause dyspnea and functional impairment. After other causes of dyspnea have been excluded, drainage of the MPE by simple thoracentesis can improve dyspnea and assist in improving ambulation and general activities. Malignant pleural effusion often recurs, challenging the physician, the patient, and the patient’s family in balancing the benefits of symptomatic improvement with the risk and inconvenience of therapy. In addition, most patients with MPE will have a median life expectance of 90 days (range, 3–9 months) depending upon the histological subtype of the primary tumor.

The management of spontaneous pneumothorax (SP) is complicated by the many clinical settings in which it occurs and the lack of accepted guidelines for management. Primary spontaneous pneumothorax (PSP) occurs in persons without obvious underlying lung disease with a reported incidence of 7.4 to 18/100,000 per year for men and 1.2 to 6/100,000 per year for women. Secondary spontaneous pneumothorax (SSP) complicates an underlying lung disease, most often chronic obstructive pulmonary disease (COPD), with a reported incidence similar to that of PSP. Because of the additional presence of the patient’s underlying lung disease, SSP is considered a potentially life-threatening event, while PSP is rarely life threatening. In this chapter, we will focus on the possible role of video-assisted thoracic surgery (VATS) as first-line therapy for patients presenting with their first episode of PSP, in contrast to the traditional approach of initial nonoperative management with surgical therapy reserved only for recurrent PSP. We will also briefly discuss the limited role of VATS as initial therapy for patients presenting with their first episode of SSP.

Pleural space infection (complicated parapneumonic effusion and empyema) is common and causes significant morbidity and mortality of up to 10%. The incidence of community-acquired pneumonia in the United States is estimated at 3.5 to 4 million cases per year with about 20% of patients requiring hospitalization. A parapneumonic effusion develops in approximately half of hospitalized patients with pneumonia, translating into 300,000 to 350,000 parapneumonic effusion annually. Most are small and resolve with antibiotics alone without pleural space sequelae. However, the effusion can progress to a complicated parapneumonic effusion (CPE) or empyema. Management ranges from observation to thoracotomy with decortication. The use intrapleural fibrinolytics, such as streptokinase, urokinase, and tissue plasminogen activator (tPA) to augment chest-tube drainage of a CPE and empyema is widespread; however, case series, cohort studies, and small randomized, controlled trials have conflicting conclusions.

Diffuse malignant pleural mesothelioma (MPM) is an aggressive tumor with dismal prognosis that has largely been associated with exposure to asbestos. As a disease of industrialized nations predominantly, it is expected to have its peak incidence around year 2020. In the United States alone, 2500 to 3000 new cases of MPM are diagnosed annually and its incidence is increasing. Based on a 20- to 50-year latency period between exposure and disease manifestation, there might still be another surge in incidence in the mid 21st century associated with asbestos exposure from the unfortunate events of September 11, 2001, at the World Trade Center in New York City. Despite important advances in our understanding of this disease, long-term survivors are rare due to delay in diagnosis and rapid disease progression. Malignant pleural mesothelioma poses a significant healthcare problem not only for patients and their caregivers, but also for industry and government in terms of the enormous cost of compensation.

Malignant pleural mesothelioma (MPM) is a rare but highly aggressive tumor of the pleura that has defied standard approaches to treatment. Left untreated, the disease carries a grave prognosis, with median survival ranging from 4 to 12 months. Surgery serves as the mainstay of treatment: the strategy with resectable tumors is to widely remove all gross disease and apply adjunctive treatments for maximal local and systemic control. This approach is necessarily aggressive, with the goal of prolonging survival and the hope of cure for patients who are treated early in the course of the disease. Extrapleural pneumonectomy (EPP), the en bloc resection of the lung, visceral and parietal pleura, pericardium, and ipsilateral diaphragm, represents the most radical surgical approach to eradicate all macroscopic tumor burden. Other surgical options, such as pleurectomy and decortication, serve to debulk tumors but inevitably leave gross residual disease within the hemithorax.

Myasthenia gravis (MG) is a disorder caused by abnormal neuromuscular transmission and can be either congenital or acquired. Acquired MG is an autoimmune disease mediated by acetylcholine receptor antibodies (AChrab) or antibodies to muscle-specific tyrosine kinase (anti-MusSK antibodies) directed against the acetylcholine receptor region of the postsynaptic membrane. Blocking and accelerated degradation of acetylcholine receptors lead to impaired neuromuscular transmission. When the safety factor for normal neuromuscular transmission is exceeded, then clinical weakness is apparent. Myasthenia gravis has a predilection for the ocular and bulbar muscles, but generalized somatic muscle weakness, particularly of proximal groups, is also common. Fatigable weakness is the hallmark of MG and the disorder is diagnosed by the clinical presentation, abnormal electrodiagnostic findings on single-fiber electromyography and repetitive nerve stimulation tests, and elevated AChrab or anti-Musk antibodies in the patients’ sera.

Perhaps one of the longest unresolved issues in thoracic surgery is the role of thymectomy in the treatment of myasthenia gravis (MG). Persistent questions and issues involve not only the surgical approach to thymectomy, but even the role of thymectomy itself in the treatment of myasthenia gravis. Many of these issues remain unclear because there is no level 1 evidence, and even level 2 evidence available to compare and analyze comparable study populations is limited. Results of many studies are as well not reported using appropriate Kaplan-Meier methodology, making analysis of the results even more challenging or ineffective. Additionally, myasthenia gravis is an entity in itself with varying degrees of severity, time courses, and self-remissions. Alfred Blalock, who pioneered and helped introduce thymectomy for myasthenia gravis beginning in 1939, was even noted in a comment in 1947 to show his doubts about the usefulness of thymectomy: “I thought we had an answer to the thymus in MG, but such does not appear to be the case” unfortunately this prophetic statement is still relevant.

Primary mediastinal nonseminomatous germ cell tumors (PMNGCT) are rare, representing less than 6% of all germ cell tumors (GCT) and 10% to 20% of all anterior mediastinal masses. These tumors can be biologically aggressive, with regional involvement of adjacent structures and a high metastatic potential. The biology of extragonadal GCT is often different than their gonadal counterparts, despite having similar histological features (Table 58.1).

The optimal treatment of patients with symptomatic pericardial effusion remains controversial. The goals of treatment are complete drainage of the effusion and acquisition of tissue and fluid for pathological analysis and microbiologic culture. Ideally, this should be performed using a method with minimal morbidity and a low risk for recurrence of the effusion. Therapeutic options include pericardiocentesis, percutaneous catheter drainage, open subxiphoid pericardial drainage (with or without the creation of a pericardioperitoneal window), and transthoracic drainage with creation of a pericardiopleural window. The choice of drainage procedure is significantly influenced by the physiological reserve of the patient and the need for a definitive diagnosis of the cause of the effusion.

Pericardial cysts are congenital lesions of the mediastinum that are usually detected using chest imaging in the absence of symptoms. Historically referred to as spring-water cysts due to their clear fluid content, the majority of published literature has suggested that surgical resection, traditionally via thoracotomy, be utilized only in symptomatic cases, with observation being sufficient for incidental, asymptomatic lesions.