Malignant pleural effusion is a common clinical problem in neoplastic diseases. Approximately half of all patients with metastatic cancer develop a malignant pleural effusion as a consequence of their disease.1 Although there have been no epidemiologic studies, the annual incidence of malignant pleural effusion in the United States is estimated to be more than 150,000 cases.2 The main problem that patients who develop such effusions experience is a reduction in the quality of life owing to symptoms such as dyspnea, chest pain (primarily related to involvement of the parietal pleura and chest wall), and cough. Treatment options for malignant pleural effusions are determined by the symptoms and performance status of the patient, the primary tumor and its response to systemic therapy, lung reexpansion after pleural fluid evacuation, and expected survival. The therapeutic goal of palliative treatment is permanent resolution of the pleural effusion. For patients who are symptomatic from pleural effusions, dramatic improvement or complete resolution of symptoms with remaining or limited recurrence of the effusion can be called a partial success. It always must be remembered that controlling a malignant pleural effusion is a local phenomenon that has no effect on the underlying systemic disease. A number of different techniques have been used over the past 20 years. The most common method is pleurodesis (i.e., obliteration of the pleural space), effected by instilling a chemical sclerosant in the pleural space after the effusion has been drained completely, either during thoracoscopy (under sedation or general anesthesia) or at bedside thoracostomy.1,3 There is no single unified approach to thoracoscopy. It can be performed by using flexible or rigid scopes with or without video assistance under local, regional, or general anesthesia and with or without selective one-lung ventilation.4 It provides access to the entire pleural cavity, permits biopsy under direct visualization, and by means of a video-assisted procedure, enables optimal preparation of the pleural surface and homogeneous distribution of the sclerosing agent under visual control, thereby maximizing the chances for complete pleurodesis.5,6 |
PREOPERATIVE ASSESSMENT Malignancy always must be in the differential diagnosis of an undiagnosed unilateral or bilateral pleural effusion, and a thoracentesis must be performed. Complete drainage of the effusion is important for evaluating the underlying lung. If the lung remains collapsed after drainage, it usually indicates trapped lung syndrome. Options in cases involving trapped lung are tailored to the individual patient and include either implantation of a chronic indwelling pleural catheter (PleurX catheter, Denver Biomedical, Inc., Golden, CO),7,8 internal drainage from the pleura to peritoneum using a Denver pleuroperitoneal shunt,9 or pleurectomy (which is performed rarely for effusion control). It is important to perform bronchoscopy when endobronchial lesions are suspected with accompanying symptoms of hemoptysis and atelectasis or, for large effusions, without contralateral mediastinal shift. Moreover, is it important to exclude endobronchial obstruction before attempting a pleurodesis when the entire lung remains collapsed after therapeutic thoracentesis.2 To determine the optimal management approach, the patient must be well examined and evaluated. Because of the limited survival of patients with malignant pleural effusions,3,7 the selected treatment should have low procedure-related mortality and morbidity. |
IDEAL PATIENT CHARACTERISTICS The ideal patient for sclerotherapy has been diagnosed recently with a malignant pleural effusion and still has a free-flowing effusion without loculations. Failure of sclerotherapy is related to the inability of the lung to expand and completely fill the pleural space, and nonexpansion is usually observed with chronic effusions that have been either neglected or tapped on multiple occasions. Thickening of the visceral pleura, leading to loss of volume and trapping of the lung, will prevent successful obliteration of the cavity wherein the fluid accumulates. A large-volume pleural tumor in addition to the fluid is also associated with failure of the technique. |
TECHNICAL PRINCIPLES Video-Assisted Thoracoscopic Surgery For video-assisted thoracoscopic surgery (VATS) procedures, general anesthesia with selective one-lung ventilation via a double-lumen endotracheal tube is commonly preferred.4,10 However, in some patients with poor cardiac workout and increased risk for general anesthesia, conscious sedation consisting of local or locoregional anesthesia and administration of systemic analgesic and sedative drugs can be used.11 After placing the patient in the lateral decubitus position and instituting selective one-lung ventilation under general anesthesia, the table should be flexed at 30 degrees to widen the rib spaces on the operative side. The skin is prepared and draped as for a standard posterolateral thoracotomy. In adult patients, 5- or 10-mm thoracoscopes are often used; however, recently a 2-mm minithoracoscope also has been recommended for diagnosis.12 For general exploration, the first (camera) port is often made in the midaxillary line at the seventh intercostal space. The first port is always made bluntly, and digital exploration is performed to detect and release adhesions around the port site before the camera is inserted. Additional trocars are inserted under video guidance. After the pleural fluid has been drained, the pleural cavity is inspected, and guided biopsy specimens are taken. In the presence of adhesions or trapped lung syndrome, adhesiolysis or limited decortication can be done to achieve complete lung reexpansion. After the lung has been observed to expand and fill the hemithorax, 5 g sterile purified talc powder is insufflated through a talc atomizer under videothoracoscopic vision to ensure that talc covers the entire visceral pleura (Fig. 101-1). At the end of the procedure, usually one or two 28F chest tubes are inserted. This practice is recommended to confirm complete expansion of the lung before the scope is withdrawn.
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POSTOPERATIVE MANAGEMENT Suction is maintained on the chest tubes for a period of 24-48 hours. The drains are removed after radiologic evidence of lung expansion has been obtained and the fluid drainage level diminishes to less than 100 mL/day.4,10,13,14 For postoperative pain management, nonsteroidal anti-inflammatory drugs can be used,10 or an epidural catheter can be placed at the time of the operation. Assessment of Results Thoracoscopy is a safe and well-tolerated procedure with a low perioperative mortality rate (0.5%).3 The success rate for VATS pleurodesis is greater than 90%3,13,15 if one uses the standard criteria for success, namely, 30-day freedom from radiographic evidence of malignant pleural effusion and equal to or greater than 90% expansion of the lung at the time of the procedure. The most recent data regarding efficacy have been reported with the results of a large randomized study of talc poudrage (n = 251) versus talc slurry (n = 250). Between 68% and 73% of the patients were able to have complete expansion of their lungs at the time of the procedure. Although there were no differences in recurrence among all the patients in the study, there was a slight improvement in the thoracoscopic success of talc poudrage (67%) compared with talc slurry (56%) with complete lung expansion (p = 0.045). Respiratory complications of thoracoscopic pleurodesis are observed more commonly in patients undergoing thoracoscopic pleurodesis as opposed to talc slurry (14% versus 6%, respectively, p = 0.007). They are the most frequent causes of treatment-related death (2-3%). Dyspnea and pain are the most common complications of the procedure. Others include postoperative fever, persistent air leak, bleeding, subcutaneous emphysema, reexpansion pulmonary edema, deep vein thrombosis, and port-site recurrence. The latter is seen in some mesothelioma patients, and controversy remains as to whether these recurrences can be prevented by postoperative local radiotherapy.3 In general, it is thought that thoracoscopic pleurodesis has the advantage of assessing lung expansion at the time of the operation and is associated with better results in breast and lung cancer effusions, yet bedside talc slurry is a simpler and less invasive technique. Indwelling Pleural Catheter The PleurX catheter (Denver Biomedical, Golden, CO) is a soft Silastic chronic indwelling catheter. It is a 66-cm-long 15.5F flexible silicone rubber catheter with fenestrations along the distal 24 cm. A valve at the proximal end prevents inadvertent leakage of pleural fluid or entry of air. A polyester cuff is situated approximately 14 cm from the proximal end and lies within a subcutaneous tract to decrease bacterial dislocation and to anchor the catheter in position. Insertion of the PleurX catheter can be accomplished in the outpatient setting under local anesthesia. With careful monitoring, it is possible to accomplish complete drainage of the effusion at the time of placement. The patient or caregiver drains the pleural fluid periodically by connecting the tubing to a disposable vacuum container to provide relief of dyspnea and potentially achieve spontaneous pleurodesis (Fig. 101-2A).
After finding the exact location of the pleural fluid by needle and administering a local anesthetic, the catheter is inserted using a modified Seldinger method. A flexible wire is passed through the needle into the thorax, and a 1.5-cm horizontal incision is made at this site (see Fig. 101-2B). A counterhorizontal incision is made approximately 5 cm inferiorly and medially to the wire, and a subcutaneous tunnel is created for the pleural catheter. The catheter is drawn through the tunnel, and the Teflon cuff is placed 1 cm within the tunnel, away from the skin edge. A peel-away sheath over a removable stylet (dilator) is inserted over the wire and placed into the thorax. The stylet is withdrawn, and the catheter is threaded through the sheath into the thorax. The peel-away sheath is withdrawn. The two skin incisions are closed with interrupted nonabsorbable sutures, and the catheter is secured to the skin. After insertion, 1000–1500 mL pleural fluid should be drained. A chest x-ray is obtained to confirm the position of the catheter and to rule out a pneumothorax, after which the patient is sent home. Detailed written and oral instructions for home catheter care and drainage should be provided to patients and their caregivers. The complications are local cellulitis, catheter obstruction, and pleural infection. Tumor seeding can be seen in some patients. At home, patients should establish a pattern of draining no more than 1200 mL at a time at a given frequency that will prevent or relieve their dyspnea. If over time the output diminishes to less than 50 mL on 3 consecutive days, the catheter can be removed. If the catheter does not drain but the patient is still dyspneic, chest x-ray or CT scan should be performed to rule out a nonfunctional catheter. By using this method, spontaneous pleurodesis can be achieved in 46–70% of patients.7,16,17 The clinical course in a patient with mesothelioma receiving palliative care for a malignant pleural effusion is depicted in Figure 101-3.
Pleuroperitoneal Shunt Pleuroperitoneal shunt (Denver Biomedicals, Inc., Golden, CO) insertion can provide effective and safe palliation for malignant pleural effusion when associated with the trapped lung syndrome. Since the development and manufacture of the PleurX catheter, use of this shunt has decreased remarkably. This procedure can be done under local or general anesthesia with either VATS or open thoracotomy, especially if there have been multiple previous interventions in the pleura, which may cause pleural adhesions. After the fluid has been drained and the entire pleura thoroughly examined, the degree of lung expansion is assessed. If it is not adequate to fill the entire hemithorax, pleuroperitoneal shunt can be an option for palliation. A 3-cm transverse incision is made in the ipsilateral rectus sheath to expose the peritoneal cavity. The pleuroperitoneal shunt is tunneled under the skin from the chest to the abdomen, with the pumping chamber lodged in a subcutaneous pocket overlying the costal margin. The pleural and peritoneal limbs then are introduced into the respective cavities under direct vision. Normal saline can be introduced into the pleural space to prime the pump and check shunt function. The site of the pump can be marked on the skin to facilitate pumping by the nurse or the patient.9 The patient's condition should be monitored by chest x-ray films. The common complications are shunt occlusion and wound infection. Other complications are owing to surgical technique and anesthesia. Tumor implantation into the peritoneal cavity is rare but can occur.9,16,18 |
SUMMARY Recent reviews suggest that thoracoscopic pleurodesis with talc may be the optimal technique for pleurodesis in patients with malignant pleural effusion.1,3,19 The optimal treatment option depends on the patient's situation and whether the patient is fit enough to undergo sedation or general anesthesia. The success rate in thoracoscopic pleurodesis in patients with malignant pleural effusion can be as high as 90%; however, it depends on the primary malignancy. If the pH values decrease below 7.3, the success of thoracoscopic pleurodesis also decreases.20 If the patient undergoing pleurodesis is receiving corticosteroid therapy, the drug should be stopped or the dose, if possible, should be reduced because it may reduce the efficacy of pleurodesis.2 |
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