Douglas J. Mathisen and Christopher R. Morse
INDICATIONS/CONTRAINDICATIONS
Prolonged air leaks are the most common complication after pulmonary resection and a significant source of morbidity in up to 26% of patients. This often leads to an extended time for a tube thoracostomy to remain in place as well as extended lengths of stay. Various techniques have been championed to prevent air leaks in the operating room and in managing and resolving them in the postoperative period.
PREOPERATIVE PLANNING
There are thought to be several preoperative predictors of persistent air leaks. Patient characteristics such as emphysema, the prolonged use of steroids and poor pulmonary function tests, specifically a diminished FEV/VC ratio. Other risk factors that may be less obvious include preoperative chemoradiotherapy, previous ipsilateral thoracic surgery often leading to the presence of adhesions, incomplete fissures, lung volume reduction surgery, and type of lobectomy.
SURGERY
Intraoperative Techniques
There have been various intraoperative techniques used in an attempt to decrease the incidence of air leaks. At the conclusion of surgery, the lung should be inspected for air leaks by reinflating under water. Attempted repair of air leaks or raw surfaces should be undertaken. Simple horizontal mattress sutures or running sutures buttressed by strips of pleura or “surgicel” is preferred. For those patients at higher risk, multiple mechanical stapler companies have created “buttressed” stapler lines, often with a biologic addition such as bovine pericardium. These are either applied to the stapling device or come as an intrinsic part of the stapler.
Many surgeons advocate for a “fissureless” resection where minimal dissection is done in the fissures lessening the incidence of parenchymal tears. With this technique, there is no dissection in an incomplete fissure, instead the dissection starts in the hilum with the vein being taken first followed by the artery and finally the bronchus. The fissure is divided last, completing the lobectomy.
The options for visceral pleural sealants are numerous and include both synthetic- and fibrin-based products. Often pleural sealants come with the disadvantage of poor handling, cumbersome activation techniques, poor adhesion, and degradation. A recent Cochrane review determined that sealants reduce postoperative air leaks and time to chest drain removal but this reduction may not be associated with a reduction in length of postoperative hospital stay. Typically, sealants are applied at the conclusion of the case with the lung partially inflated so air leaks can be identified. Some have advocated the use of strips of “surgicel” to create a patch with sealant.
Residual space in the chest following a pulmonary resection is an issue and several techniques can help avoid this problem. All intrapleural adhesions should be divided during the operation, allowing the lung to move and fill the residual space. With upper lobe resections and large visceral pleural rents, the apical pleura can be dissected and released as a pleural tent. This is allowed to drape on the pulmonary parenchyma, creating a tissue buttress. The chest tube is placed under the tent to help “suction” the tent onto the lung. Along the same lines, for an upper lobe resection, division of the inferior pulmonary ligament is important in allowing the residual lung to expand and fill the chest. With lower lobe resections, a transient pneumoperitoneum can be induced with a temporary catheter to raise the diaphragm and achieve apposition with the lung. The catheter can be placed through the diaphragm and injected with air. Alternatively, a peritoneal dialysis catheter can be placed through the midline fascia. This can be done at the conclusion of the operation if anticipated or within the first 24 hours. Delay is associated with a less favorable result. The patient is positioned upright in bed to gain maximal result. Initially 50 cc of air is instilled sterilely. Every 15 to 20 minutes another 5 to 10 cc can be instilled until the desired result is achieved or the patient is uncomfortable. This can be repeated as needed over a 24- to 48-hour period. Although rarely used, some surgeons will induce a phrenic nerve paralysis with a local anesthetic, again allowing the diaphragm to raise and oppose visceral pleural defects.
If space and air leak are anticipated, the latissimus dorsi muscle can be harvested and transposed into the pleural cavity to obliterate the space and oppose the surface of the lung. Some advocate intraoperative pleurodesis or pleurectomy as an addition to the operative procedure for particularly troublesome situations.
POSTOPERATIVE MANAGEMENT
The management of postoperative air leaks is varied and greatly influenced by the experience of the surgeon. A prolonged postoperative air leak is defined as greater than 5 days in the Society of Thoracic Surgeons database.
In regard to chest tube management, the balance of evidence suggestion that transitioning a patient to water seal rather than active suction may lessen the duration of air leaks. This should be done in the absence of a large, increasing pneumothorax or increasing subcutaneous emphysema. The majority of air leaks that allow the transition to water seal will resolve without further intervention. Those that do not resolve in several weeks time can be transitioned to a Heimlich valve, which allows for the discharge of patients with the chest tube remaining in place and with the patient returning to the office for removal. Caution should be exercised if a pleural space exists with the air leak as the Heimlich valve will serve as a foreign body and predispose to infection.
With a larger leak that does not tolerate water seal, a chemical pleurodesis after major pulmonary resection is described, typically performed with the installation of talc. Sclerosants are known to incite a vigorous inflammatory response in the pleura providing substrate for symphysis and obliteration of the pleural space and cessation of air leak. Our standard protocol for talc pleurodesis is an initial 5 to 7 days of suction to allow the lung to adhere to the chest wall. A water seal film is obtained and if the lung remains inflated, 4 g of talc slurry is injected after sterilely preparing the rubber tubing connecting the chest tube. The tube is not clamped, but draped over an IV pole 30 to 40 cm above the level of the heart to allow air to be expelled, but not allow the talc to drain (Fig. 52.1). The patient is turned in multiple positions to help uniformly distribute the talc in the chest. After 30 to 60 minutes the chest tube is returned to suction. The procedure can be repeated once. Failure to control the leak typically then requires transposition of a pectoralis major flap (Figs. 52.2 and 52.3) for apical leaks or the use of a Heimlich valve. In the same context, an autologous “blood patch” has been described with the instillation of blood via the chest tube.
Figure 52.1 With talc pleurodesis in the management of an air leak, the chest tube is not clamped, but draped over an IV pole 30 to 40 cm above the level of the heart to allow air to be expelled, but not allow the talc to drain.
Finally, in extremely rare cases, air leaks that are unable to be managed but any of the above techniques will require reoperation. We advocate for bronchoscopy to rule out a bronchial dehiscence. The remaining lung can occasionally be “restapled” to address the leak, often in conjunction with a pleurectomy or decortication. Residual space can be addressed with a muscle flap (described above and elsewhere in text) or rarely mobilization of the omentum, also described elsewhere in the textbook.
Figure 52.2 Mobilization of pectoralis major muscle. Note skin incision to mobilize muscle and blood supply is the pectoral branch of the thoracoacromial artery. Muscle is detached from humerus and mobilized from the clavical to give the most freedom.
Figure 52.3 Mobilization of the muscle into the pleural space is best accomplished resecting a segment of the second rib.
COMPLICATIONS
Prolonged air leaks are a significant cause of morbidity, increased hospital stay, cost, and even death after pulmonary surgery and have been reported to occur in up to 26% of patients after pulmonary resection. Furthermore, air leaks of greater than 7 days have been associated with an empyema rate of 8.2% compared with 0% in patients without prolonged air leaks, leading to significant morbidity and occasionally mortality.
RESULTS
Several reports of the various management options for air leaks have been published. Cerfolio et al. described a comprehensive algorithm for the management of postoperative chest tubes including sequence of removal and the use of Heimlich valves, leading to a decrease in hospital stay. Multiple reports of various sealants are available, with varying rates of success. Finally Liberman et al. published a recent report of the use of pleurodesis with talc in the management of persistent air leaks leading to a greater than 90% success rate.
Recommended References and Readings
Cerfolio RJ, Bass C, Katholi CR. Prospective randomized trial compares suction versus water seal for air leaks. Ann Thorac Surg. 2001;71:1613–1617.
Liberman M, Muzikansky A, Wright CD, et al. Incidence and risk factors of persistent air leak after major pulmonary resection and use of chemical pleurodesis. Ann Thorac Surg. 2010;89(3):891–897.
Merritt RE, Singhal S, Shrager JB. Evidence-based suggestions for management of air leaks. Thorac Surg Clin. 2010;20:435–448.
Singhal S, Ferraris VA, Bridges CR, et al. Management of alveolar air leaks after pulmonary resection. Ann Thorac Surg. 2010;89:1327–1335.