120: Thoracoscopy with Intrapleural Sclerosis for Malignant Pleural Effusion

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 200,000 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.²

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 must always 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 to treat malignant pleural effusion.³ 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.^1,4 There is no single unified approach to thoracoscopy. It can be performed by using flexible or rigid thoracoscopes, with or without video assistance, under local, regional, or general anesthesia, and with or without selective one-lung ventilation.⁵ 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 guidance, thereby maximizing the chances for complete pleurodesis.^6,7

Malignancy must always 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,^8,9 internal drainage from the pleura to peritoneum using a Denver pleuroperitoneal shunt,¹⁰ 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 if the entire lung remains collapsed after therapeutic thoracentesis.¹¹

To determine the optimal management approach, the patient must be thoroughly examined and evaluated. Because of the limited survival of patients with malignant pleural effusions,^4,8 the selected treatment should have low procedure-related mortality and morbidity.

The ideal patient for sclerotherapy has been recently diagnosed 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 reexpand and completely fill the pleural space, and nonexpansion is usually observed with chronic effusions that have been either neglected or drained on multiple occasions. Thickening of the visceral pleura, leading to loss of volume and trapping of the lung, will prevent successful obliteration of the pleural cavity. A large volume pleural tumor is also associated with increased failure of the technique.⁴

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.^5,12 However, in some patients with poor cardiac output and increased risk for general anesthesia, conscious sedation consisting of local or locoregional anesthetics and administration of systemic analgesic and sedative medications can be used.¹³

After placing the patient in the lateral decubitus position and instituting selective one-lung ventilation under general anesthesia, the table should be flexed to 30 degrees to widen the intercostal 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, a smaller 2-mm mini thoracoscope can be used for diagnostic procedures. For general exploration, the first (camera) port is often made in the midaxillary line in the seventh intercostal space. The first port site tunnel is always created bluntly, with digital exploration 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 directed 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, chemical pleurodesis is performed by instilling a chemical irritant such as talc, doxycycline, silver nitrate, or iodopovidone into the pleural space to promote adhesion of the parietal and visceral pleurae.³ Five grams of sterile purified talc powder (most commonly used) is insufflated through a talc atomizer under video-thoracoscopic vision to ensure that talc covers the entire visceral pleura (Fig. 120-1). At the end of the procedure, usually one or two 28 F chest tubes are inserted. This practice is recommended to maintain complete expansion of the lung after the thoracoscope is withdrawn. Of note, if the pH values decrease below 7.3, the success of thoracoscopic pleurodesis decreases.¹⁴ Also, if the patient undergoing pleurodesis is receiving corticosteroid therapy, the medication should be stopped or the dose, if possible, should be reduced because it may reduce the efficacy of pleurodesis.¹¹

Suction is maintained on the chest tubes for a period of 24 to 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 per day.^5,12,15,16 For postoperative pain management, nonsteroidal anti-inflammatory drugs can be used,¹⁷ 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%).⁴ The success rate for VATS pleurodesis (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) is greater than 90%.^4,15,17 In a large randomized study by Dresler et al.¹⁸ 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 respect to complete lung reexpansion (p = 0.045). Respiratory complications (atelectasis, pneumonia, or respiratory failure) of thoracoscopic pleurodesis were observed more commonly in patients undergoing thoracoscopic pleurodesis as opposed to talc slurry (14% vs. 6%, respectively, p = 0.007), and were the most frequent causes of treatment-related deaths (2% to 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 of malignancy. The latter is seen in some mesothelioma patients, and controversy remains as to whether these recurrences can be prevented by postoperative local radiotherapy.⁴ 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, however, bedside talc slurry injection is a simpler and less invasive technique.

Indwelling Pleural Catheter

The PleurX Catheter System (CareFusion Corp., San Diego, CA) is a soft Silastic chronic indwelling catheter. It is a 66-cm-long, 15.5 F 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 then 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. 120-2A).

After localization of the pleural fluid by needle and administering a local anesthetic, the catheter is inserted using a modified Seldinger technique as follows. A flexible wire is passed through the needle into the thorax, and a 1.5-cm horizontal incision is made at this site (Fig. 120-2B). A counter-horizontal 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 within the tunnel, 1 cm 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 then withdrawn leaving the catheter in situ. The two skin incisions are closed with interrupted nonabsorbable sutures, and the catheter is secured to the skin. After insertion, 1000 to 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. Complications of indwelling pleural catheter placement include local cellulitis, catheter obstruction, and pleural infection. Tumor seeding can be seen in some patients.

At home, patients should drain no more than 1000 to 1500 mL at a time to prevent reexpansion pulmonary edema. Drainage should be performed at a frequency that will prevent or relieve their dyspnea. If over time the output diminishes to less than 50 mL per day for three 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 nondraining effusion. By using this method, spontaneous pleurodesis can be achieved in 46% to 70% of patients.^3,8,19,20

The clinical course in a patient with mesothelioma receiving palliative care for a malignant pleural effusion is depicted in Figure 120-3.

Pleuroperitoneal Shunt

Pleuroperitoneal shunt (Denver Biomedical, 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 dramatically. This procedure can be done under local or general anesthesia with either VATS or open thoracotomy depending on 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 are then 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.¹⁰ Palliative efficacy should be monitored by chest x-ray films.

Common complications of pleuroperitoneal shunting 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.^10,20,21

Available data suggest that thoracoscopic pleurodesis with talc may be the optimal technique for pleurodesis in patients with malignant pleural effusion.^1,4,18 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 of thoracoscopic pleurodesis in patients with malignant pleural effusion can be as high as 90%; however, success rates vary with the type of primary malignancy and patient factors such as concomitant steroid use or decreased pleural fluid pH. If pleurodesis fails, indwelling pleural catheters or pleuroperitoneal shunts can provide symptomatic relief.

Malignant pleural effusions are a common problem. Long-term indwelling pleural catheters have become the most common treatment of malignant pleural effusions. Thoracoscopy with intrapleural sclerosis, however, continues to play a strong role as a consequence of the benefits of the procedure. One advantage of a pleural catheter is that it can be placed at the bedside with local anesthesia and obviates the need for general anesthesia in the frail patient. If the patient is not frail, I believe thoracoscopy should be offered. My standard procedure under general anesthesia is flexible bronchoscopy, exploratory thoracoscopy, drainage of effusion, removal of loculations, pleural biopsy under direct vision, testing of the ability of the underlying lung to expand and fill the chest, placement of the sclerosis agent or pleural catheter (if lung is entrapped), and intercostal nerve block. Although pleural drainage catheters have become popular for a quick and easy way to control the effusion and slowly expand an entrapped lung, there remain several advantages to the thoracoscopy. Thoracoscopy can be combined with single lung anesthesia or a single-lumen endotracheal tube with low tidal volumes or short periods of apnea with lung collapse if a large unilateral effusion allows clear visualization. Thoracoscopy allows for breakdown of loculations, complete drainage of the effusion, and uniform distribution of the sclerosant. If I find an entrapped lung, I leave a pleural catheter. If no entrapment, I add a sclerosant. Although the efficiency of pleural catheters and thoracoscopy are similar, patient satisfaction is higher with the thoracoscopic approach.