Decortication 

Updated: Feb 10, 2020
Author: Shabir Bhimji, MD, PhD; Chief Editor: Zab Mosenifar, MD, FACP, FCCP 

Overview

Background

Decortication is a surgical procedure that removes a restrictive layer of fibrous tissue overlying the lung, chest wall, and diaphragm. The aim of decortication is to remove this layer and allow the lung to reexpand. When the peel is removed, compliance in the chest wall returns, the lung is able to expand and deflate, and patient symptoms improve rapidly.[1]

In most people, the pleural space is less than 1 mm thick. When this space is violated by any number of pathologic disorders, the distribution of certain cells and fluid can be altered, with serious medical consequences.[2]  One common pathologic process that affects the pleural space is fibrothorax, which is an abnormal accumulation of fibrous tissues over the lung or visceral pleura. The deposition of fibrous tissues over the lung parenchyma can be so intense that the underlying lung fails to expand. Over time, the lung becomes entrapped or encased.[1]

Although decortication is an effective surgical procedure for this condition, its success depends on careful selection of patients. As in all thoracic surgery procedures, the preoperative workup should be thorough, and the surgery should be done at a particular timed interval. Moreover, the surgeon should also be technically skilled at entering the chest and removing the peel. In some cases, the intercostal space is fused, and it is almost impossible to enter the chest cavity.

Indications

The primary indication for decortication in a patient with fibrothorax is presence of symptoms due to lung restriction resulting from development of a thick fibrinous peel.[3]  The timing of surgery is vital for success. In many cases, the peel may spontaneously resolve, and the symptoms may subside.[4]  Most surgeons will perform a decortication for the following conditions:

  • The pleural peel has been present for more than 4-6 weeks
  • Lung symptoms are disabling
  • There is radiologic evidence of a trapped lung

Decortication is frequently necessary when other minor interventions (eg, chest tube) have not resulted in clearance of the infection or hemothorax. Tuberculous empyema is usually first treated with drugs, and decortication is only undertaken after long-term drug therapy fails.

Pleurectomy-decortication has been described in the treatment of malignant pleural mesothelioma.[5, 6, 7]  Pleurectomy-decortication may be defined as consisting of total parietal and visceral pleurectomy with sparing of the pericardium and the hemidiaphragm, whereas extended pleurectomy-decortication may be defined as the above plus resection of the pericardium and the hemidiaphragm when required.[8]

Contraindications

Other than physiologic unfitness on the part of the patient, there are no absolute contraindications for decortication. In some patients who also have underlying lung disease, removal of the peel may not help the lung expand, and thus surgery would be futile.

Other conditions that may make decortication futile include the presence of a pleural-space infection and large-airway stenosis. In such cases, the lung will not expand to fill the pleural space. A more extensive pleuropneumonectomy may be the sole available option, but only if the patient has been worked up preoperatively. Pleuropneumonectomy is a major undertaking with a very high mortality.

Decortication may not be possible in the presence of uncontrolled lung infection or contralateral lung disease or for a chronically debilitated patient. Medical optimization may be required before surgery is undertaken in these patients. Ideally, the patient's nutritional status should first be normalized (with nasogastric feedings if necessary), and sepsis should be controlled with appropriate antibiotic therapy.

Other relative contraindications include coagulopathy, severe chest-wall infection, and terminal disease.

Technical Considerations

Anatomy

The boundaries of the pleural space are the visceral pleura, which envelops the lungs, and the parietal pleura, which is the inner lining of the thoracic cavity.[9]  The goals in performing decortication are to remove all the fibrinous peel and necrotic tissue, to help the lung reexpand, and, equally important, not to leave any residual air spaces.[10]

The two most common problems encountered in performing decortication are pleural-cavity infection and fibrosis.[11]  It is difficult for the underlying lung to expand when there is a thick peel overlying the parenchyma. Consequently, there is a large residual space left in the chest cavity that almost always becomes infected. Therefore, for the surgeon to have good success with decortication, the timing of surgery is crucial.

If the disease has been chronic, the rib spaces are often fused, and the chest cavity is severely constricted. Entry into the chest can be very difficult. If the peel is very thick and adherent, injury to the lung parenchyma can occur with moderate air leak. If the lung has an inherent disorder, the possibility of reexpansion may not occur. Finally, decortication is not a trivial procedure and can be very bloody; thus, the patient must also be physiologically fit enough to undergo the procedure. All these factors must be considered in planning a decortication.[12]

Moreover, once the chest cavity has been entered, no lung may initially be visible because of the thick fibrous peel. The peel can vary in thickness from a few millimeters to few centimeters. One may also find necrotic debris and abscess along the chest cavity. It is important to avoid dissection along the medial border of the lung because the heart chambers are close by. The dissection should be started on lateral aspects or near the fissures. In most cases, the lower lobe is fused with the diaphragm, and one can easily enter the abdominal cavity if the dissection is too deep.

For safe decortication, the chest cavity is best entered at the fifth or sixth intercostal space and dissection should be started where the peel is the thinnest and easily removed. It is important to reassess the anatomy every few minutes to prevent injury to the organs. Blind digital peeling should be avoided, especially near the apex of the lung. This area is best approached when the upper lobe can be retracted inferiorly and the lung apex is visible. Severe bleeding from injury to the subclavian vessels and pulmonary artery has been reported.

Because extensive decortication or radical pleurectomy can be associated with air leaks, methods have been described for reconstructing the diaphragm so as to help lower the incidence of postoperative complications.[13, 14, 15]

When performing video-assisted thoracoscopic surgery (VATS), one must be aware of the adjacent structures to avoid injury. On the superior aspect, the subclavian vessels can be found lying deep to the pleura but clearly visible. Along the medial border, one may come across the thymus, the trachea, the heart, the phrenic nerve, the aorta (on the right), the vena cava (on the left), and the esophagus (posteriorly). In the posterolateral chest, one may come across the sympathetic chain, the azygos vein, and the diaphragm (inferiorly).[1, 9]

Procedural planning

Decortication gives the best results in patients who seek early treatment. Fibrothorax is a time-dependent process and can be prevented. Depending on the cause, insertion of a chest tube to remove an effusion or hemothorax may prevent the development of fibrothorax.

Among patients with chest trauma who suffer a hemothorax, placement of a chest tube and complete drainage usually prevents development of fibrothorax. Numerous studies have shown that early and complete evacuation of clotted hemothorax and parapneumonic effusions leads to decreased morbidity and mortality.

Some of the reasons that may explain an incomplete return of lung volume include elevation of the diaphragm, mediastinal shift, intercostal muscle fibrosis, or decrease in size of the thoracic cavity. Some experts believe that the longer the empyema is allowed to progress, the lower the likelihood that lung function will return back to normal. Although some authors report an association between shorter course of disease and improved outcomes, this is not a universal finding among all surgeons.

Although studies have not explained failure of the lung to expand after so-called successful decortication, the most likely reason is either technical difficulties or incomplete removal of the peel. In many cases, the plane of dissection can be difficult. Too much persistence in removing the thin peel can also injure the underlying lung parenchyma and result in massive air leaks.

Inability to define the plane of dissection between the peel and the visceral pleura is an especially troublesome technical challenge that can adversely affect results. If visceral pleurectomy is performed, air leakage and postoperative hemorrhage may compromise pulmonary function. Care must be taken throughout the operation to protect the phrenic nerve from injury; fortunately, this usually is not an issue, because the mediastinal pleura is rarely involved in the inflammatory process. Incomplete parietal pleurectomy or inability to free the diaphragm may also compromise results.

If patients are appropriately selected, complete reexpansion of the lung after decortication can usually be achieved. Occasionally, however, an issue related to residual pleural space might arise after an otherwise technically satisfactory decortication. If this space is not obliterated, failure is inevitable.

Outcomes

The results after decortication are often fruitful. Morbidity and mortality after this procedure are dependent on patient age, underlying comorbidities, and development of complications from the surgery. In general, decortication has an excellent outcome in young people.

In younger patients with benign causes of fibrothorax, outcome is typically excellent and quality of life much improved.[16]  Most patients begin to feel relief of symptoms soon after surgery. In elderly patients with multiple comorbidities, recovery is often slow, but symptom relief is also better. The majority of patients regain their previous exercise endurance and are able to return to their original work.

However, when the procedure is done in patients with compromised lung function, morbidity can be high. Besides surgery itself, the thoracic incision and general anesthesia also carry a high morbidity in people with no lung reserve. Older data suggest that overall mortality in healthy people is less than 1% but may run as high as 4-6% in individuals with underlying lung disease. With VATS, however, mortality figures have tended to be slightly lower.[17, 18, 15]

To avoid complications, the surgeon must pay attention to detail. The peel should be removed with great care, and injury to nearby organs should be avoided. If the decortication is done adequately, lung function improves remarkably. However, the ultimate return of lung function depends on preoperative lung disease.

If the lung parenchyma was normal prior to surgery, then complete reexpansion of the lung and obliteration of the pleural space is certainly possible. In most cases, lung volumes improve after decortication, but it is rare to see a return to preoperative values.

 

Periprocedural Care

Patient Education and Consent

Informed consent should be obtained from all patients. The possibility that a video-assisted thoracoscopic surgery (VATS) procedure may have to be converted to an open thoracotomy should be included in the discussion.

Preprocedural Planning

In the preoperative workup, it is important to find out the cause of the fibrothorax.[1]  The two most common causes that lead to fibrothorax in North America are traumatic hemothorax and parapneumonic effusion.[19, 20, 21]

All thoracic surgery procedures carry definite risks as well as benefits. Preoperative identification and amelioration of these risks will enhance postoperative outcomes. Factors that increase postoperative risk include the following:

If any of the above issues are present, it is important to work up the patient to avoid unnecessary complications. Important details in the preoperative workup should include the following:

  • Thorough history and physical examination
  • Pulmonary function test
  • Spirometry
  • Cardiopulmonary exercise test

Routine pulmonary function tests that must be done for all patients undergoing thoracic surgery include lung volume, lung mechanism, airflow, and gas exchange. These tests can help define the degree of lung dysfunction and help the surgeon stratify the risk.

Pulmonary function testing may reveal moderate-to-severe lung function in patients with fibrothorax. However, these values should not be a contraindication for surgery, because the majority of patients will improve once the peel is removed.

Cardiac workup

It is also important to assess the cardiac risk factors in patients undergoing decortication. Thoracic surgical procedures have the highest incidence of associated postoperative congestive heart failure, arrhythmias, and myocardial reinfarction. A thorough cardiac history is vital in the preoperative valuation of patients, and the findings should be correlated with appropriate physical findings and results of laboratory testing.

Patients who are completely asymptomatic and have no cardiac risk factors for CAD, regardless of age, do not need testing. Patients with symptomatic heart disease or laboratory evidence of a cardiac dysfunction suggestive of cardiac disease need further assessment. If symptoms of cardiac disease are present, stress testing should be considered.

Preoperative education of the patient should include techniques for maintaining good bronchial hygiene. The patient must be taught how to generate an effective cough. Pillows should also be provided to help the patient forcefully exhale.

Diagnostic imaging

The first imaging modality in a patient with suspected fibrothorax or empyema is always chest radiography (see the first image below). However, computed tomography (CT) of the chest (see the second image below) is routine because it offers better resolution and localization and defines the fibrous peel and disease process. CT can also assess the presence of any associated lung disease (eg, pneumonia, bronchiectasis, or cancer).

A 23-year-old man with a stab to the right chest p A 23-year-old man with a stab to the right chest presented 1 week later with fever, chills, and dyspnea. The radiograph shows an inflammatory process that did not drain via a needle.
CT scan showing a large collection in the right ch CT scan showing a large collection in the right chest. The collection is surrounded by a thick peel that is typical of empyema.

The presence of other lung diseases, such as tuberculosis or mesothelioma, may play a significant role in surgical decision-making.[1]  It is important to rule out cancer in the differential diagnosis of fibrothorax because the treatment approach for a malignant mesothelioma is quite different from that for a benign fibrothorax.[23]

The improvement in shortness of breath, reexpansion of lung, and parenchymal function may be estimated on the basis of the lung function tests and the CT scan. Eventually, it is the surgeon's clinical judgment that plays a key role in the decision whether to perform surgery or to undertake a conservative medical approach.

The majority of early parapneumonic effusions are thin and readily aspirated. In the fibropurulent stage, the fluid becomes viscous, and a chest tube may not always work, especially if the fluid is loculated or there is clotted blood. In such cases, cleaning of the chest can be performed by means of VATS. The thin peel can be removed along with all the debris. This allows the underlying lung to reexpand.[24]

Patient Preparation

The patient is positioned in the lateral decubitus position with the affected side up. An axillary roll is essential, and a sandbag may be used for support. Great care should be taken to pad all pressure points. Both the front and the back of the patient should be supported with a sandbag. Pillows should be placed in between the legs. The patient's entire chest is prepared with povidone-iodine and draped. The draping should be wide enough just in case there is a need for a thoracotomy.

 

Technique

Approach Considerations

As with all thoracic surgical procedures, bronchoscopy is performed before patient positioning. It is essential to identify any large-airway pathology (eg, bronchial stenosis, broncholith, malignancy, or mucus plug) that may be the cause of lung collapse.

The patient is intubated, and the operation is done with the patient under general anesthesia. Single-lung ventilation is rarely necessary, because the lung on the affected side is already compressed from the fibrothorax. In fact, surgery becomes easier when the lung is expanded.

Thoracoscopic Approach

Video-assisted thoracoscopic surgery (VATS) is an option for most patients with thoracic pathology. Various studies have found VATS to be associated with better outcomes, less pain, and quicker recovery than the open approach.[25]

VATS is currently the gold standard for early cases of empyema. There is some evidence to suggest that it may also be an effective and safe choice for late-stage empyema in selected cases.[26, 27, 28]  However, a systematic review and meta-analysis by Sokouti et al did not find VATS decortication to be clearly superior to open decortication in the treatment of empyema thoracis.[29]

VATS is a better alternative to thoracotomy and is typically done with general anesthesia, using a camera and two trocar ports. (A uniportal approach has also been described.[30, 31] ) The VATS technique is very similar to the open technique, except for the instruments used to retract and dissect.[32]

Local anesthetic is injected into the skin sites where the ports are to be inserted into the chest cavity. In general, the camera is usually in the midaxillary line, and the two additional ports are placed on either side of the camera. The entire oepration can be performed through these three ports; rarely, a fourth port may be required for retraction of the tissues or for suctioning of smoke, pus, or blood.

During the early disease process, the peel is usually thin and easily removable from the lung parenchyma; in such cases, VATS is the ideal treatment modality. The thoracoscopic approach can help remove the peel, clean the necrotic debris, and break up any loculations. When the disease process becomes chronic, thoracoscopy is often difficult because the ribs may be fused and the peel may be very thick. The risk of injury is very high in chronic cases; thus, thoracoscopy is best avoided.

The fibrin peel is removed in a piecemeal fashion from the parietal and visceral pleura. Great care is required in removing thin peel from the visceral pleura because this can lead to air leaks. During the procedure, the scope may be switched to a different port to yield a better view of the lung. The peel may be removed with a grasper or peanut dissector.

Once the peel has been removed and the pus suctioned out, the chest cavity is irrigated. Two chest tubes are inserted via the port sites. The scope is removed, and the underlying subcutaneous tissues and skin are closed.

Open Approach

The patient should be placed in the lateral decubitus position. The chest is entered at the premarked intercostal space (usually the fifth or sixth intercostal space). An axillary thoracotomy also may be performed, but this exposure is only good for apical disease and does not give great exposure to the lower chest. (See the image below.)

Image shows approach to a patient with empyema. Th Image shows approach to a patient with empyema. Thoracotomy is usually required for longstanding empyema since the ribs are often fused and the fibrosis is intense.

Although some surgeons prefer to spare the latissimus dorsi and the serratus, this is sometimes difficult to do in patients with empyema. Often, the muscles are edematous or contracted and hard to dissect off the chest wall. However, every effort must be made to preserve the muscles because they may be needed to cover residual airspace or air leak.

In many cases of chronic empyema, the procedure can be made easier by first resecting a rib in a subperiosteal fashion. This maneuver also provides an intercostal muscle flap, avoids breaking another rib during chest opening, and facilitates good exposure of the entire chest.

In most chronic cases, the pleura are fused, and it is simply easier to perform pleurectomy. If the adhesions between the visceral and parietal pleura are not dense, then one may proceed with sharp dissection of the adhesions.

Once the correct plane of dissection is visualized, the peel can be removed relatively easily. In most cases, however, the peel is removed in segments. The entire lung must be checked to confirm that the peel has been fully removed; otherwise, the lung may fail to reexpand.

A pleurectomy that is too deep may cause parenchymal injury with resulting air leaks. These air leaks can prolong hospital stay. The anesthesiologist should be asked to inflate the lung gently during the procedure. This allows the peel to become more prominent and more easily detachable from the lung surface. Traction and countertraction are key. Of course, it is inevitable that some minor injury to lung parenchyma will result, but the resultant air leaks usually seal over very quickly.

Sometimes, it may be necessary to use a scalpel to make an incision in the thick peel and define the plane of dissection. The peel can be grasped with a hemostat and then dissected with a peanut dissector or the back end of a DeBakey forceps.

Patience is essential in performing decortication. Proceeding too quickly simply increases the chance of injury to the lung parenchyma and consequent air leakage. The peel should be followed laterally, medially, and superiorly over the lung surface. It is vital to remove the peel from the lung fissures and all the way down to the diaphragm.

In most cases, the thickest segment of the peel is along the costodiaphragmatic surface. Most of the peel here can be removed with finger dissection, but care should be exercised in placing the fingers along the medial border. In this are, it is possible to injure the phrenic nerve, the blood vessels, or the diaphragm. If the peel thins out or is difficult to remove, one should not persist but should move to another site. Some segments of the peel should be sent for pathologic and microbial analysis.

Once the peel is removed, the lung is checked to confirm that it is capable of complete reexpansion. Any large parenchymal air leaks that are noted may be oversewn, but this step often is not necessary. There are several pulmonary sealants now commercially available that can reasonably be used to close air leaks.

One chest tube is placed along the base of the diaphragm, and one is placed in the apex. The chest should be irrigated, and all blood should be suctioned because it can be a nidus for infection.[33]

Alternative Approaches

For some patients, neither VATS nor an open thoracotomy may be appropriate; in such cases, there are other options.

On rare occasions, thoracoplasty with multiple rib resections may be considered to obliterate any infection in the residual space by bringing the chest wall down to fill the space. One may leave a chest tube for prolonged periods; remove a segment of the rib in the most dependent position to allow for drainage.

These secondary options are only for frail and ill patients. For most patients with diffuse pleural disease, decortication is still the criterion standard.[34]

Postoperative Care

The management of a patient who has undergone decortication is essentially the same as that of a patient who has undergone lobectomy. However, recovery of lung function is faster after decortication than after lobectomy.

The decision to initiate or continue mechanical ventilation is usually based on an assessment of gas exchange, impending respiratory failure, and the ability to protect the airways. Some patients have an indwelling arterial line placed by the anesthesiologist in the operating room (OR) to facilitate one-lung anesthesia. Arterial blood gas sampling should be frequently done to assess both arterial oxygen tension (PaO2) and arterial carbon dioxide tension (PaCO2). Most patients do well with oxygen delivery by a face mask or nasal cannula. The majority of patients can be extubated in the OR.

If a monitored bed on the surgical floor is not available, an overnight stay in the intensive care unit (ICU) is recommended. The majority of patients who undergo thoracic procedures are observed in the ICU or in a stepdown unit for 12-24 hours. If the course is uneventful, the patient may be discharged to a monitored surgical floor. To reduce fluid overload, most thoracic patients are kept on the dry side. Unless the patient is not eating at all, intravenous (IV) fluids are maintained at a minimum.

Postoperative management of the chest tube is dictated by culture results, intraoperative findings, and the patient's clinical status. Chest tubes are monitored for both air leakage and fluid drainage every 8 hours. Blood work is usually done once on the following day to assess hemoglobin and renal function. Postoperative chest radiography is routine. Unless the patient has a problem, some physicians only order radiographs before and after removal of a chest tube.

Judicious use of analgesia is necessary. Patient-controlled analgesia (PCA) is routinely available in most hospitals and helps ease the pain for the next several days. Once the chest tubes are removed, the patient can be placed on transdermal fentanyl, augmented by nonsteroidal anti-inflammatory drugs (NSAIDs). Whenever possible, surgeons should attempt an intercostal block. Very fine catheters can be placed along the posterior rib angles. Bupivacaine and epinephrine can be infused intermittently via these catheters.

Other factors in postoperative care include chest physiotherapy, tracheal suctioning, and ambulation. To prevent atelectasis, incentive spirometry is vital and should be apart of preoperative teaching. The cardiovascular system also must be closely monitored after surgery. Arrhythmias and myocardial infarction can occur; thus, cardiac monitoring for the first 48 hours is required. The incidence of cardiac complications is higher in the elderly and those with preexisting cardiac risk factors.

Most patients remain in the hospital until the chest tubes have been removed and they are able to tolerate oral feeding. Physical therapy is a vital component of postoperative care and should be encouraged. Deep vein thrombosis (DVT) prophylaxis is highly encouraged, even if patients are ambulatory. Because patients may be present or past smokers, oxygen and nebulizer therapy is often administered. The average stay after a thoracotomy procedure ranges from 3 to 5 days, but patient who undergo VATS may be able to go home within 48-72 hours.

Numerous series show that VATS allows for rapid recovery, significantly less pain, and reduced postoperative complications. Irrespective of the type of surgery performed, most patients need a prescription-strength pain pill for a few days at home. Others may benefit from a fentanyl patch.

All patients are seen within 5-7 days after discharge. At the first postoperative visit, the staples may be removed, and a wound check is performed. Chest radiography is done to assess for the presence of full lung expansion, pneumothorax, or pleural effusion. All patients are encouraged to continue with physical therapy.

Complications

Decortication is associated with a wide range of complications, including infections (perioperative sepsis syndrome), bronchopleural fistulas, bleeding, and persistent air leakage. Prolonged air leakage or bronchopleural fistula may necessitate a second surgical procedure in some cases.

Most air leaks seal within a few days, but large leaks may persist for weeks.

Bleeding can occur from the lung or the pleural surface or from lysis of adhesions. Thus, it is vital to ensure good hemostasis before leaving the OR. Most surgeons secure blood vessels with a suture as well as a clip.

Residual air space is a frequent problem and can occur when there is injury to the lung parenchyma.

Infection of the pleural space can occur when a residual air space persists. In some cases, the patient may need a muscle flap or an apical tent to close off the residual space and eliminate the infection.

Respiratory failure is not a direct complication of surgery. Patients who have borderline lung function are more likely than healthy people to develop respiratory distress in the postoperative period. If the preoperative workup was not adequate or if a high-risk patient underwent surgery, tha patient may require prolonged ventilation and even a tracheostomy.

Cardiac complications may include acute myocardial infarction and arrhythmias.