Shair Ahmed and Allan Pickens
Introduction
Originally described by Hippocrates over 2,000 years ago, the clinical signs and symptoms of an empyema were recorded, including the implication for abscess drainage, in order for the patient to improve. In the early 1900s, Samuel Robinson from the Mayo Clinic reviewed techniques of thoracoplasty for empyema cavity obliteration known during the early 1900s; however, he advocated for open pleural drainage with rib resection and subsequent muscle interposition as the treatment for chronic nontuberculous empyema. Following this, two pinnacle papers served as the foundation to the current management of chronic empyema. First in 1935, Eloesser introduced a “U”-shaped flap for the treatment of tuberculous empyema; subsequently, Clagett and Geraci from Mayo Clinic reported on their experience with a two-stage procedure for the treatment of postpneumonectomy empyema in 1963. Modifications of both procedures have led to the current treatment termed the open thoracic window (OTW) for chronic empyemas and postpneumonectomy empyema.
Thoracic empyema is defined as an inflammatory process between the visceral and parietal pleura. Empyema is diagnosed by one or more of the following methods: (1) the visualization of frank pus by aspiration, tube thoracostomy, or at time of surgery; (2) biochemical evidence of inflammation defined as white blood cell count greater than 500/mL, protein level greater than 2.5 g, glucose level less than 40 mg/dL, lactate dehydrogenase level greater than 1,000 IU/L, or pH less than 7.1; or (3) positive culture from fluid-aspirated pleural fluid. The most common etiology of an empyema is parapneumonic infection, while less than 30% originates from thoracic operations. Less than 5% of cases of empyema result from thoracic trauma. Table 23.1 below lists all the modalities of treatment that exist for dealing with empyema, the main focus of this chapter will describe the technical aspects of the Eloesser flap and Clagett procedure.
INDICATIONS
The indications for an OTW (Eloesser flap or Clagett window) are as follows:
Chronic empyema
Patients with significant comorbidity and prohibitive surgical risk who are not able to tolerate decortication.
TABLE 23.1 Treatment Modalities for Thoracic Empyema
Patients waiting for a more radical procedure (allows for nutritional buffering)
No response to conventional therapy
Patients who are unresponsive to treatment modalities, which include tube thoracostomy and decortication.
Patient too debilitated for a major thoracic procedure
Expectation of long-term drainage
Discomfort from tube drainage placed posteriorly
Patients who are noncompliant
Postpneumonectomy empyema (with or without bronchopleural fistula)
SURGERY
Original Description of Eloesser Flap
The original procedure was described using local anesthesia. A U-shaped flap of skin and subcutaneous tissue is initially marked before making incision (Fig. 23.1). This U-shaped flap is half way between the posterior axillary line and the line at the inferior most portion of the scapula. The base of the flap is 2-in wide and is one rib space above the lower extent of the empyema cavity. The length of the flap is equivalent to the length of two rib spaces to ensure the flap reaches the pleural space. The rib and associated intercostal muscle directly beneath the flap is resected to the length of the flap itself. The tip of the flap is placed into the chest and the flap is sutured to the pleura at the apex and laterally using absorbable suture (Fig. 23.2). The wound is subsequently packed. As the lung parenchyma expands, the cavity collapses. The flap acts as a one way valve as an increase in intrapulmonary pressure creates negative pressure within the empyema cavity allowing the lung to re-expand and obliterate the space (Fig. 23.3).
Modified Eloesser Flap (MEP)
This technique was introduced into the literature in 1971 by Symbas et al. Essentially the principles are the same as the original technique described by Eloesser in 1935. Again, the procedure can be performed with local or general anesthesia. The location of the MEP is dependent on the location of the empyema cavity. In contrast to the original technique, an inverted U flap is incised over the empyema cavity. The flap includes skin and the subcutaneous tissue. The base of the flap is directly over the lower most extent of the empyema (in contrast to the original EF where the base of the flap is two rib spaces over the lower extent of the empyema cavity). The length of the flap is approximately two ribs including intercostal spaces. A segment of the underlying rib is resected, or multiple segments of one or more ribs may be resected depending on the size of the empyema and the body habitus of the patient. The flap is then sutured to the base of the cavity using large absorbable suture (Fig. 23.4A–F).
Figure 23.1 Flap of skin outlined.
Figure 23.2 Cross section of chest wall showing skin flap turned into chest and attached to pleura.
Figure 23.3 Skin flap turned into chest cavity; edges of defect approximated by sutures.
Figure 23.4 A–F: Creation of MEP.
Original Description of Clagett Procedure
The Clagett procedure is a two-stage procedure. If the patient has a previous thoracotomy, the anterior most portion of the thoracotomy is opened and the underlying rib is exposed. Approximately 7 to 9 cm of rib is exposed and resected including the associated intercostal muscle and neurovascular bundle. The pleura is then opened and the empyema cavity is drained and thoroughly irrigated. The superficial fascia is sutured to the periosteum of the resected rib. No drainage tubes are required. The cavity is irrigated daily and the quality of infected drainage should improve to a serous composition.
The original time recommended between phase one and phase two was 6 to 8 weeks. This time span allows the empyema cavity to reduce due to the ipsilateral shift of the mediastinum and the elevation of the diaphragm. At this point, the cavity should have a fibrotic lining free of any purulence. The edges of the wound should be debrided sufficiently and the underlying muscle and fascia should be mobilized. The cavity is irrigated with an antibiotic solution. Following thorough irrigation, antibiotic solution should be placed in the cavity to fill the entire space. Debridement antibiotic solution (DAB, 500-mg neomycin, 100-mg polymixin B sulfate, and 80-mg gentamicin per liter of saline) has been described for this purpose. Care should be taken to not overfill the pleural space with antibiotic solution. The muscle and fascia are closed over the cavity in multiple layers with no drainage tube.
Modifications to Both the Eloesser Flap and Clagett Procedure
Over time, there have been several modifications to both procedures. Consequently, the operation is now referred to as an OTW. An Eloesser flap usually implies a one-stage procedure and is performed in patients who have significant comorbidity that precludes multiple procedures or general anesthesia. Multiple approaches to the incision used over the empyema cavity have been described including the original U shape, the inverted U shape, an H shape, and triradiate. The surgical principle is to create musculocutaneous flaps in a window that is large enough to drain the cavity and prevent spontaneous closure of the cavity. When the window is marsupialized and anchored to the pleura, the chance of spontaneous closure is reduced by assuring that epithelial skin is sutured to the parietal pleura. The large epithelialized fistula into the chest allows free drainage of the empyema. Dressing changes are frequent at the creation of the window; however, the frequency gradually decreases to once daily. Over time, the cavity decreases in size and reepithelializes with minor-to-moderate chest wall deformity. If the cavity is too large, a second procedure is required to close the defect. Contraindications to closure include persistent infection, communicating bronchopleural fistula, or disseminated carcinoma.
Two other important concepts exist in management of chronic empyemas, especially ones due to a bronchopleural fistula. First, the bronchopleural fistula must be closed. BPFs are controlled by debridement and reclosure of the bronchial stump, reresection of the stump with carinal closure, or muscle flap transfer. The second concept involves those circumstances where the pleural cavity remains too large and requires obliteration. Muscle flap transfer for obliteration of residual plueral cavity has been well described in the literature and muscle flaps used include latissimus dorsi, serratus anterior, pectoralis major, omentum, and rectus abdominus. Figure 23.5 demonstrates the commonly used muscle flaps for thoracomyoplasty.
Key principles in muscle flap closure include tailoring antibiotics specific to the cultures from the empyema, reopening the original incision with debridement of the empyema cavity to ensure a healthy granulation tissue base, addressing a BPF if present, using indicated muscle flaps to fill the pleural space and to ensure the entire pleural cavity is filled. Entry sites for latissimus dorsi flaps include the second or third rib (with segment of rib resected) to cover the superior mediastinum, or the fifth/sixth rib for coverage of the middle to inferior mediastinum. Serratus anterior and pectoralis minor usually require removal of a segment of the second or third rib in the midaxillary line and provide coverage for the mediastinum. Rectus abdominus and omental flaps are both transposed through the diaphragm. In the case of rectus abdominus, the flap is transposed specifically through the anterior portion of the diaphragm. Omentum is particularly useful in the buttressing and closure of a bronchial stump.
Figure 23.5 Commonly used muscle flaps for thoracomyoplasty.
RESULTS
Once an OTW has been created, management involves daily dressing changes to sterilize the cavity over time. A recent study from Cleveland Clinic demonstrated a median time to closure of 454 days, (range: 90 days to 3 years). Zaheer et al. in 2006 reviewed their 16-year experience with the Clagett procedure for postpneumonectomy empyema in which 89.5% of patients had successful closure of the Clagett procedure. A literature review in 2002 reviewed all reported results of the Clagett procedure from 1972 to 1990 with nearly 79% success; the majority of failures resulting from a recurrent or persistent BPF. An institutional review described factors that affected closure of an OTW. An immediate decision for an OTW had significantly less closure time of 3 months compared with delayed timing and a median time to closure of 11 months. Early empyemas were associated with longer closure times as opposed to empyemas that developed late. With the more frequent use of vacuum-assisted closure (VAC) device for chronic wounds, an application to OWT has been reported. The largest study known from Palmen et al. in 2009 compared VAC to the contemporary management of OWT. Patients excluded from VAC therapy included patients with esophageal fistula, postpneumonectomy fistulas, and large bronchopleural fistulas. The use of VAC devices allowed for re-expansion of the pulmonary parenchyma and establishment of granulation tissue. All wounds were subsequently closed using pedicled latissimus dorsi or rectus abdominus flaps. There were no associated VAC complications reported in this study.
CONCLUSION
OTW includes the Eloesser flap and the Clagett procedure with subsequent modifications that have been introduced in the literature. This largely remains the treatment for chronic empyema and postpneumonectomy empyema. Key concepts include early recognition and treatment. The underlying etiology of the empyema should be identified. While this remains a long-term chronic surgical issue with relative morbidity to patients, this is an entity that can be managed with successful outcomes as demonstrated in the literature since the 1970s.
Recommended References and Readings
Adams F. The Genuine works of Hippocrates. New York, NY: W. Wood and Company; 1886:248–249.
Clagett OT, Geraci JE. A procedure for the management of postpneumonectomy empyema. J Thorac Cardiovasc Surg. 1963; 45:141–145.
Deslauriers J, Jacques LF, Gregoire J. Role of Eloesser flap and thoracoplasty in the third millennium. Chest Surg Clin N Am. 2002; 12:605–623.
Eloesser L. An operation for tuberculous empyema. Surg Gynecol Obstet. 1935;60:1096–1097.
Harris SU, Nahai F. Intrathoracic muscle transposition. Surgical anatomy and techniques of harvest. Chest Surg Clin N Am. 1996; 6:501–518.
Massera F, Robustellini M, Pona CD, et al. Predictors of successful closure of open window thoracostomy for postpneumonectomy empyema. Ann Thorac Surg. 2006;82:288–292.
Miller JI Jr. The history of surgery of empyema, thoracoplasty, Eloesser flap, and muscle flap transposition. Chest Surg Clin N Am. 2000;10:45–53.
Molnar TF. Current surgical treatment of thoracic empyema in adults. Eur J Cardiothoracic Surg. 2007;32(3):422–430.
Palmen M, van Breugel HN, Geskes GG, et al. Open window thoracostomy treatment of empyema is accelerated by vacuum-assisted closure. Ann Thorac Surg. 2009;88(4):1131–1136.
Puskas JD, Mathisen DJ, Grillo HC, et al. Treatment strategies for bronchopleural fistula. J Thorac Cardiovasc Surg. 1995;109(5):989–996.
Reyes KG, Mason DP, Murthy SC, Su JW, Rice TW. Open window thoracostomy: Modern update of an ancient operation. Thorac Cardiovasc Surg. 2010;58:220–224.
Robsinon S. The treatment of chronic non-tuberculous empyema. Surg Gynecol Obstet. 1916;22:557–571.
Shamji FM, Ginsberg RJ, Cooper JD, et al. Open window thoracostomy in the management of postpneumonectomy empyema with or without bronchopleural fistula. J Thorac Cardiovasc Surg. 1983;86:818–822.
Symbas PN, Nugent JT, Abbott OA, Logan WD, Hatcher CR Jr. Non tuberculous pleural empyema in adults. Ann Thorac Surg. 1971; 12:69–78.
Thourani VH, Lancaster RT, Mansour KA, Miller JI. Twenty-six years of experience with the modified Eloesser flap. Ann Thorac Surg. 2003;76:401–406.
Zaheer S, Allen MS, Cassivi SD, et al. Postpenumonectomy empyema: Results after the Clagett procedure. Ann Thorac Surg. 2006;82:279–287.