Surgery of Pleural Diseases Staff Members of Cardio-thoracic Surgery Departments Egypt

Definition The pleura is a thin serous membrane lined by mesothelial cells that surrounds the lungs (Visceral pleura) and lines the inside of the chest wall, diaphragm and mediastinum (Parietal pleura) . The pleural space is the potential space between visceral and parietal pleurae. It is normally at subatmospheric pressure, which keeps the lungs inflated. The pleural fluid: Only a few (10-20) milliliters of liquid, which helps lubricate the normal "to and fro" motion of the lungs during breathing.

Objectives Pleural Effusion Empyema Haemothorax (Chapter of trauma) Pneumothorax (Chapter of trauma) Chylothorax Mesothelioma Procedures

I) PLEURAL EFFUSION

PLEURAL EFFUSION Definition: It is an abnormal collection of fluid in the pleural space resulting from excess fluid production or decreased absorption.

Types: Hydrothorax: accumulation of serous fluid in pleura Haemothorax: accumulation of blood in pleura Pyothorax (Empyema thoracis): accumulation of pus in pleura Chylothorax: accumulation of chyle in pleura

Etiology of hydrothorax: The normal pleural space contains fluid, representing the balance between (1) hydrostatic and oncotic forces - plasma proteins - in the visceral and parietal pleural vessels and (2) extensive lymphatic drainage. Pleural effusions result from disruption of this balance. (3) Inflammatory process of the capillary wall results in increased exudation.

Types of Hydrothorax: Pleural effusions are generally classified as transudates or exudates, based on the mechanism of fluid formation and pleural fluid chemistry. 1. Transudates (an imbalance in oncotic and hydrostatic pressures, low in proteins, usually systemic) Congestive heart failure. Hepatic failure. Renal failure. Hypoalbuminemia.

2. Exudates (the result of inflammation of the pleura or decreased lymphatic drainage. High in proteins, usually local causes) Infections (bacterial, tuberculous, fungal, parasitic, viral). Malignancy (1ary tumour as mesothelioma, 2aries from lung cancer, metastases, lymphoma…). Collagen disease (rheumatoid Lupus,..) . Pulmonary embolus. Pseudochylothorax (chronic condition with elevated cholesterol in pleural fluid) Abdominal disease (pancreatitis, subphrenic abscess,…) . Drug induced. Miscellaneous (esophageal perforation, postoperative, radiation therapy, sarcoidosis, iatrogenic, Meig’s syndrome…). Idiopathic.

Clinical Picture: Small effusion may be asymptomatic. Large effusion may be associated with dyspnea, dry cough, chest pain (more with exudative effusion, pleuritic chest pain indicates inflammation of the parietal pleura) and low cardiac output syndrome if under tension.

Signs of the cause Local: o Inspection: Limited chest movement + chest bulge o Palpation: Decreased TVF+ mediastinal shift o Percussion: Stony dullness o Auscultation: Decreased air entry + pleural rub

Investigations: 1. Laboratory: CBC, ESR,… 2. CXR : Blunting of the costophrenic angle is an early radiologic sign. It already indicates accumulation of more than 400 ml of fluid. A lateral decubitus film confirms the presence of free-flowing (vs. loculated) pleural fluid.

CXR left pleural effusion

Hydropneumothorax

3. CT scanning and ultrasound: Assess pleural effusion, underlying lung, associated intrathoracic pathology. Localize fluid prior to thoracocentesis. Plan biopsy or surgery.

4. Diagnostic Thoracentesis: Aspiration of pleural fluid to establish the diagnosis. The aspirate is subjected to: Physical examination: colour, odour, specific gravity. Gross appearance: Bloody effusions occur with malignancy, post traumatic, after traumatic tap, with pulmonary embolus or tuberculosis. Milky fluid suggests chylothorax. Pus is diagnostic of empyema. a. Physical examination: Clear yellowish fluid in hydrothorax Microbiology: Culture and sensitivity & acid fast bacilli. : in suspected pyothorax Cytology: RBC, WBC. Malignant Cells: positive in up to 80% in 3 successive samples to detect malignant cells and its type.

Chemical Examination: Total protein. Exudate (>3g/dl), transudate (<3g/dl). The ratio of pleural protein/serum protein is <0.5 in transudate and >0.5 in exudate. LDH. Ratio of pleural LDH/serum LDH >0.6 suggests an exudate. Glucose. Low (<60mg/dl) suggests malignancy, tuberculosis, parapneumonic effusion or rheumatoid effusion. PH. Parapneumonic effusion with low pH (<7.0) suggests progression to empyema. Amylase. Elevated in pancreatitis, esophageal perforation, and malignant effusion. Triglycerides. High level (>110mg/dl) are diagnostic of chylothorax. Cholesterol: High in pseudochylothorax. Pleural complement, rheumatoid factor, antinuclear antibody are elevated in collagen vascular diseases. Tumor markers. (Alpha fetoprotein and Carcinoembryonic antigen)

Light’s criteria: To differentiate between transudate and exudate, if one criterion is positive it means exudative effusion: 1. Pleural protein > 0.5 serum protein 2. Pleural LDH > 0.6 serum LDH 3. Pleural LDH > 2/3 upper normal limit of serum LDH

5. Pleural biopsy:   Abrams needle pleural biopsy (blind technique). Ultrasonic guided. CT guided. Thoracoscopic (VATS). Open (mini-thoracotomy).

ABRAMS PLEURAL BIOPSY NEEDLE

Treatment:  Transudates and some exudates: treatment of underlying cause. Medical treatment:  Symptomatic treatment: anti-tussives, analgesics  Diuretics and protein supplementation Drainage with thoracocentesis or intercostal tube (thoracostomy) connected to an underwater seal for moderate and massive effusions.   Therapeutic thoracentesis: no more than 1 L to 1.5 L of fluid should be removed in one setting to avoid re-expansion pulmonary edema and post-thoracentesis shock. The maneuver can be repeated. Malignant pleural effusion: pleurodesis, surgery, home management with indwelling pleural catheter.

1. Pleurodesis: Definition: Fusion between visceral and parietal pleura. Types: Mechanical: intraoperative or thoracoscopic Chemical: by injecting sclerosing agent into chest tube as: Talc powder, Tetracycline, Blood, Betadine, cytostatic agents as Bleomycin, Viscum, cisplatinum or 5-fluorouracil . Technique: Chest tube inserted. Once all fluid is drained, a “sclerosing” agent is placed into the chest cavity. The sclerosing agents cause an inflammatory reaction that obliterates the potential space in the chest cavity (pleural symphysis). When the drainage decreases, the chest tube can be removed. is indicated in recurrent symptomatic malignant effusions.

2. Surgery: Thoracoscopic surgery (VATS): For diagnosis and management @ drainage of collections of fluid and adding a sclerosing agent @ removing the lining of the chest cavity (pleurectomy) for pleurodesis. Thoracotomy: for complicated pleural effusions. Pleurectomy and decortication. 3. Home management of an indwelling pleural catheter: The PLEURX® catheter is used; it is a soft, 16F elastic catheter with a one-way valve for safety and polyester cuff for long term placement. When the drainage ceases, the catheter can be removed.

Pleurx catheter after placement

II) Empyema Thoracis

Empyema Thoracis Definitions: Thoracic empyema is accumulation of infected fluid or pus in the pleural cavity. It may be localized or involve the entire pleural space. 

Etiology: Contamination from contiguous sources: Lung: Pneumonia (the most common cause) & Lung abscess, Mediastinitis & Mediastinal abscess (esophageal perforation). Direct inoculation: (Post traumatic): Penetrating chest injuries. Iatrogenic as complication of thoracocentesis & postoperative as post resection bronchopleural fistula. Transdiaphragmatic spread from subphrenic abscess. Hematogenous spread from distant sites.

Pathogenesis The commonest isolated organisms are: Aerobic: Gram-positive: Streptococcus, staphylococcus. Gram-negative: Coliforms, proteus, H.influenzae. Anerobic: Bacteroids.

Pathology The evolution of parapneumonic effusion into empyema involves 3 stages: Exudative: Thin pleural fluid occurs in response to pleural inflammation. Thin fibrin is deposited over pleural surfaces. If the pleural space is drained, the lung will re-expand. Fibrinopurulent: Bacterial invasion of the pleural fluid, influx of polymorphs, and the fluid becomes turbid and purulent. Heavy fibrin deposition prevents lung re-expansion & produces loculations. Organization: Pus is very thick. Ingrowth of fibroblasts into fibrin sheet coating the visceral and parital pleura with collagen (fibrous tissue) formation. The lung is trapped in thick fibrous peel "pleural peel" causing entrapment of the lung.

Time-scale and overlapping of stages of thoracic empyema

Complications of untreated empyema: Pulmonary: fibrosis and chest wall deformities. Spontaneous drainage of pus through chest wall (empyema necessitatis) or through bronchial tree (bronchopleural fistula). Local spread of infection to pericardium or mediastinum and rare to subdiaphragmatic area. General complications of chronic sepsis: clubbing of the fingers and pulmonary osteoarthropathy, general toxemia and cachexia, amyloidosis, septicemia and septic embolization. Distant infection (osteomyelitis). Septic shock and Multi-organ failure.

Clinical Stages of Empyema Thoracis Clinical Picture Clinical Stages of Empyema Thoracis Acute empyema stage: Within the first 2 weeks of the onset. Subacute empyema: Empyema after 2 weeks till becoming chronic empyema. Chronic empyema stage: Failure of complete lung expansion (entrapment of lung with the formation of the thick peel and loculations) after proper drainage of pus (well-functioning chest tube). It is not a matter of time. Generally, after 2 weeks.

Clinical Picture Cont. 1- Clinical presentations of the cause (pneumonia) Chest pain, purulent sputum and Dyspnea. 2- Clinical presentations of infection (e.g. Fever, malaise, weight loss or toxemia. Tachycardia) 3-Clinical presentations of fluid in pleural space (depends on its amount). Small amount may have a normal physical examination. Large amount: o Inspection: decreased chest expansion. o Palpation: If a large effusion is present mediastinal shift may be detectable by tracheal deviation and displacement of the apex beat to the opposite side. o Percussion: stony dullness. o Auscultation: reduced or absent breath sounds.

Investigations: Laboratory: Leucocytosis, high sedimentation rate. 2. Imaging: CXR: Posteroanterior and lateral. 175- 500 ml needed to blunt costophrenic angle. CT: Differentiating empyema, lung abscess, or subphrenic abscess. Assess loculations, thickness of pleural peel, coexisting thoracic disease. Ultrasound: Define pleural collections and loculations, prior to percutaneous drainage.

Investigations: Cont. 3. Thoracocentesis : Pus is examined for: Physical: color, nature and odor. Pleural fluid may vary from a clear yellow liquid to thick foul-smelling pus. (Foul-smelling fluid indicates an anaerobic infection). Biochemistry: High protein (exudate > 3g/dl), high LDH (>1000 IU/l), low pH (<7.2), low glucose (<40mg/dl). Light's criteria +ve for exudate. Microbiology: Smears and cultures for organisms (Gram staining, acid-fast bacilli staining, fungal (KOH) staining, culturing and sensitivity testing for aerobic and anaerobic organisms and fungi). Cytology: pus cells.

The following criteria are accepted for the diagnosis of thoracic empyema: 1- Frank pus at tapping or organisms demonstrated on Gram stain (direct) or culture (indirect) 2- All of the tests positive for: pH ˂ 7.2 Glucose level of fluid ˂ 40 mg% LDH ˃1000 IU/ml Protein level ˃ 3 g/dl WBC ˃ 15 000 cells/mm3.

A- CXR left empyema free in pleural space (blunt costophrenic angle and the upper limit rises towards the axilla); B- Right loculated empyema.

Small amount: obliteration of costophrenic angle and rising towards the axilla. Moderate below the hilum. Massive exceeding the hilum.

Air fluid level: in case of pyopneumothorax

CT Scan: Right and left empyemas CT Scan: Right and left empyemas. CT scanning is superior to plain chest radiography in Identify adhesions and loculations may detect endobronchial obstruction may detect lung abscess

Ultrasonography

Basic rules for treatment Medical Management: Control of causative organisms, Aggressive physiotherapy, nutritional support in every phase of treatment Drainage: of the content of infected space. Elimination of the cavity and complete lung expansion

Treatment: I- Medical management: General: Treat underlying cause, associated medical conditions (diabetes mellitus), respiratory physiotherapy, antipyretic analgesics, fluids and nutrition. Antibiotics: Systemic antibiotics directed by thoracocentesis culture and sensitivity. Generally successful for stage I NOT stage II or III. Local irrigation with antibiotics is not recommended. Metronidazole is added for anaerobic infection. (Foul-smelling fluid indicates anaerobic infection).

II- Drainage: Treatment Cont. Thoracentesis without pleural drain placement is not recommended. Image-guided small bore pleural drain placement can only be considered in patients that are not surgical candidates. Insertion of pigtail catheter (8 fr to 14 fr) with administration of fibrinolytics such as streptokinase or urokinase until the pleural space is cleared. Closed intercostal tube drainage: Is the preferred first line for early stage acute empyema. The tube is connected to closed underwater seal drainage. It is removed when the lung re-expands.

Treatment Cont. Chest tubes Early insertion before the formation of loculated pleural effusion Position the chest tube in a dependent part of the pleural effusion Large-bore (32-36F) tubes are recommended

Treatment Cont. Causes of failure of empyema drainage: a-Non-dependent drainage, b- tube inserted too far, c- tube too small, d-peel too thick due to late drainage, e-bronchopleural fistula and f-presence of foreign body.

Treatment Cont. III- Options to manage patients with empyema who have incomplete lung expansion: 1- Open intercostal tube drainage: the tube is connected to a drainage bag (not under water seal) till lung inflation. This can be done in chronic empyema, after more than 3 weeks of closed drainage if only a small pleural pocket remains.

Treatment Cont. 2- Rib resection: This can be done for chronic cases if the patient’s general condition cannot withstand decortication. A segment (4-6 cm)of 1-3 ribs is resected subperiosteally in a dependent position. A chest tube is placed into the pleural pocket for irrigation and open drainage. The intercostal vessels running along the lower border of that rib is ligated and cut away. Ligation of the intercostal vessels will prevent their erosion by the tube if it is left for a long time. 3- Eloesser flap: It is a type of rib resection where the skin is sutured to the pleura to prevent premature closure and allow prolonged drainage of empyema cavity. The procedure will need prolonged wound care and dressing changes.

Eloesser flap

Treatment Cont. 4- Decortication: To remove all purulent fluid, fibrinous debris, thickened parietal pleura & Resection of visceral pleural peel to re-expand the lung; through: A- VATS decortication: In early cases (stage II) if the patient can tolerate single lung ventilation. B- Surgical decortication: Posterolateral thoracotomy in chronic cases with thick peel and loculations (stage III empyema), and if the patient cannot tolerate single lung ventilation.

Treatment Cont. 5- Tissue flaps: consisting of pedicled muscle flaps or omentum to fill empyema cavities where there is space created by incomplete lung expansion after decortication or to close a bronchopleural fistula.

Treatment Cont. 6- Thoracoplasty (Deroofing or Multiple rib resections): used to obliterate persistent pleural spaces after decortication and for bronchopleural fistulas when the patient will not tolerate surgical closure of the fistula. The principle behind thoracoplasty is that by removing the skeletal support, the overlying chest wall will collapse to the visceral pleura obliterating the residual infected cavity. By obliterating the infected cavity the complications of chronic sepsis mentioned above are avoided. Original Thoracoplasty (Schede): involves removal of the ribs as well as the intercostal muscles and the thickened parietal pleura over the entire cavity. The cavity is left open and packed with gauze. It is of historical interest only, as the modern thoracoplasty has largely replaced it. Modern Thoracoplasty (Alexander): Tailored subperiosteal resection of several ribs overlying the residual space is performed. The intercostal muscles and parietal pleura are not removed. This allows collapse of the intercostal and chest wall muscles to obliterate this space and close the bronchopleural fistula.

CXR showing right sided thoracoplasty

III- CHYLOTHORAX

CHYLOTHORAX Definition: Abnormal accumulation of chyle in the pleural space due to either disruption or obstruction of thoracic duct. High content of triglycerides, and chylomicrons. Right > left (since most of the duct is within the right hemithorax). Pseudochylothorax (cholesterol pleurisy) occurs with long-standing fluid in fibrotic pleura. The fluid has a high content of cholesterol but no triglycerides or chylomicrons.

Anatomy of the thoracic duct From cisterna chyli >>> Passes through the aortic hiatus of diaphragm >>> Continues in a rightward position between the aorta and azygos vein >>> At level of fifth thoracic vertebra, it crosses over the vertebral column behind the esophagus >>> To left posterior mediastinum >>> Arches over the subclavian artery in the superior mediastinum >>> Empty near junction of left internal jugular and subclavian veins.

Anatomy of the thoracic duct Cont. Thoracic duct crosses the mediastinum at fifth thoracic vertebra. Lymphatic injury or obstruction below this level results in a right–sided pleural effusion. Disease above this level usually leads to a left–sided effusion.

Anatomy of the thoracic duct

Etiology Congenital: birth trauma or thoracic duct abnormalities. Traumatic: Blunt trauma: Spinal hyperextension results in direct rupture of the duct above the diaphragm. Penetrating injury: Iatrogenic: During surgery of the aortic arch, PDA, subclavian artery, and esophagus as transhiatal esophagectomy. Neoplastic: Extrinsic compression >>>Thoracic duct obstruction (lymphoma). Direct invasion of the duct with lung or esophageal cancer. Intrinsic benign tumors (lymphangioma, mediastinal hygroma). Infections: Tuberculous lymphadenitis, filariasis, or ascending lymphangitis.  Spontaneous: Violent coughing or vomiting may result in shearing at the right diaphragmatic crus. Venous thrombosis: SVC, left subclavian or jugular veins. Idiopathic.

Clinical Picture: Postoperative: Milky chest tube drainage, usually on resumption of oral intake (24-72 hours). Nonoperative: Dyspnea, physical and radiological evidence of pleural effusion.  

Investigations: Thoracocentesis: Gram stain: Lymphocytosis, no bacteria. Sudan III stain: Fat globules. Fat content > plasma. Lipid analysis: Cholesterol/triglyceride ratio<1. Lipoprotein electrophoresis: Chylomicrons.  Radionucleide scanning: 99Tc antimony sulfide colloid demonstrates the level of thoracic duct obstruction and site of leakage.   Lymphangiography: Demonstrates the site of obstruction and leakage. CT scanning: Define associated thoracic pathology (mediastinal tumors).

Treatment: Conservative: Within 2 weeks, 50% would close spontaneously. Intercostal tube drainage. NPO. TPN. Operative: Daily drainage of 1000 ml (adults) or 100 ml/year of age (children) over 7 days is an indication of surgical intervention. Right thoracotomy (or thoracoscopy) and mass ligation of the thoracic duct above the right hemidiaphragm in the azygo-esophageal recess. Direct ligation at the site of leak (open or thoracoscopic ) is less effective . Other procedures include: Anastomosis of the thoracic duct to the azygous vein, fibrin glue, radiotherapy, Pleurodesis with talc.

IV) Pleural Mesothelioma

III) Pleural Mesothelioma Mesothelioms is a rare cancer that develops in the mesothelium. Pleural mesothelioma is the most common type of mesothelioma. Associated with asbestos exposure with a latent period of at least 20 years and up to 40 years. Difficult diagnosis by cytology, Therefore, usually a biopsy is recommended.

Pleural Mesothelioma, cont. Three histological subtypes: i) Epithelial, ii) Sarcomatous, and iii) Mixed. Median survival from time of diagnosis is 12-18 months.

Pleural Mesothelioma, cont.

Pleural mesothelioma, cont. Treatment: Chemotherapy, surgery, irradiation, immunotherapy have all been used with limited success. Pleurodesis gives symptomatic relief of pleural effusion.

MESOTHELIOMA Definition Types of Pleural Mesothelioma Tumor arising from mesothelial surfaces (pleura, peritoneum or pericardium). Types of Pleural Mesothelioma 1. Localized Arises from mesothelial lining of the lung. Well-defined encapsulated tumor, not associated with asbestos exposure, may be benign or malignant. May be asymptomatic discovered incidentally on CXR, or symptomatic presenting with cough, chest pain and dyspnea. Treatment is complete surgical resection. 2. Diffuse Always malignant, associated with asbestos exposure.

Pathologic types Epithelial, sarcomatoid, mixed. Differentiated from metastatic adenocarcinoma with electron microscopy and immunohistochemistry.

Investigations Clinical Picture Dyspnea, chest-wall pain, weight loss, weakness, anorexia, fever. Investigations Radiography (CXR, CT, MRI and PETscan): Pleural effusions, pleural thickening, mediastinal lymph nodes and distant metastases in advanced tumors. Thoracocentesis. Pleural needle biopsy. Thoracoscopy and pleural biopsy. Open pleural biopsy.

CXR left mesothelioma

CT of left mesothelioma

Treatment Radiation: Palliate chest-wall or mediastinal involvement. Chemotherapy: Response is disappointing. Immunotherapy: Promising with interferon. Surgery : Thoracoscopy and talc pleurodesis for effusion. Pleurectomy and decortication is difficult and palliative. Extrapleural pneumonectomy: En bloc resection of pleura, lung, ipsilateral hemidiaphragm and pericardium. Mortality is high. Combined modality therapy: Surgery combined with radiotherapy and / or chemotherapy.

Surgical procedures

Thoracentesis. The patient sits upright and leans on a table Thoracentesis. The patient sits upright and leans on a table. After local anesthesia, the needle is introduced above the upper border of the lower rib (Avoid the neurovascular bundle). Excess fluid from the pleural space is drained into a bag.

Intercostal chest tube Indications: To drain abnormal contents of the pleural space as in cases of hemothorax, pneumothorax, hemopneumothorax, empyema, chylothorax, and some cases of effusion. At the end of any thoracotomy. With other modalities as pleurodesis in spontaneous pneumothorax and malignant effusions, and fibrinolytic therapy in loculated empyema.

Compliations: Pain, wrong insertion, empyema, prolonged air leak, and pneumothorax.

Chest tube insertion Insertion Site In the fifth intercostal space between the anterior and mid-axillary lines, behind pectoralis major. This region is termed the “safety triangle”. The safety triangle is outlined by the anterior border of the latissimus dorsi muscle, the lateral border of the pectoralis major muscle, and a horizontal line at the level of the nipple. At 5th space since on expiration diaphragm rises Count down from manubriosternal junction (2nd rib)

Important Landmarks

How to insert an intercostal tube?

Underwater Seal It is an effective one way valve allowing air and fluid to go out of the pleural cavity. All attachments should be secure and leak free. The intercostal tube should be clamped if the bottle needs to be disconnected. The bottle must be kept below the level of the thorax.

Under water seal: @Below the level of the chest Under water seal: @Below the level of the chest. @The tubes should be clamped before disconnection.

Mobilization

When to remove the tube? Clinically: Equal air entery on both sides. Minimal oscillations in the tube (no air leak, pleural drainage < 150cc/day). Radiologically lung expanded.

Thoracoscopy

Thoracoscopy Video Assisted Thoracoscopic Surgery (VATS)

Thoracotomy RIB SPREADER

RIB APPROXIMATOR or CONTRACTOR Used to approximate the ribs at the end of thoracotomy operations.

LUNG RETRACTOR Used to retract the lungs during thoracotomy .