GS
General Surgery

PEARLS IN THORACIC SURGERY

March 21, 2015.
Edward Savage, MD, Chair, Cardiothoracic Surgery, Cleveland Clinic, Weston, FL

Educational Objectives

The goal of this program is to improve the surgical treatment of thoracic disorders. After hearing and assimilating this program, the clinician will be better able to:

1. Discuss the management of pneumothorax.

2. Understand the therapeutic approaches and their
complications in treating hemothorax.

3. Outline appropriate treatment strategies for the various stages of lung cancer and for pulmonary metastases.

4. Describe methods of preventing and treating tracheoesophageal and tracheoinnominate fistulas in adults.

5. Recognize the advantages and disadvantages of
partial pulmonary resection.

Summary

Pneumothorax: cause may be traumatic, spontaneous (most common in teenagers and patients with chronic obstructive pulmonary disease), iatrogenic, or catamenial (associated with menstrual cycle); tension pneumothorax — results in collapse of lung and pushing of mediastinum to opposite lung; can lead to respiratory compromise and reduction in venous return to heart; emergency; presentation — pain or shortness of breath; diagnosis by chest radiography; treatment — if small, <3 cm from apex, observation possible, but radiography should be repeated within few hours to make sure not expanding or developing tension; large or expanding pneumothorax requires therapy; if patient severely compromised (eg, hypotension, severe shortness of breath, hypoxia), needle decompression quickest solution, and immediately relieves tension; chest tube must be placed to complete expansion; if pneumothorax limited and not expanding, aspiration alone possible, but most require chest tube; recurrent pneumothorax or prolonged air leak — options include thoracoscopic resection of apical bleb or pleurodesis; site of leak can sometimes be identified intraoperatively and may be amenable to targeted stapling

Pleural effusion: classified as transudates or exudates; transudates may be caused by congestive heart failure and cirrhosis; etiologies of exudates include neoplasms, infection, pancreatitis, and autoimmune disease; distinguishing transudate from exudate — pleural protein level >0.5 of serum protein level, pleural lactate dehydrogenase (LDH) >0.6 of serum level, and pleural LDH 1.67 of normal pleural level all suggestive of exudate; helpful because transudate more likely to resolve by simple drainage or therapy

Treatment: transudate can be treated with thoracentesis; care taken not to create pneumothorax; ultrasonography sometimes useful to locate fluid; risk for pulmonary edema from re-expansion, so not advised to remove more than 1 to 1.5 L of fluid; chest tube — useful for large or recurrent effusions; ensure that effusions not complex and loculated, because attempt to drain these will be unsuccessful; surgical treatments — for loculated effusions thoracentesis useful for diagnosis, but surgery usually required to completely remove infection and reexpand lung; if etiology uncertain or effusions have been repeatedly drained, thoracoscopy for pleural biopsy or pleurodesis may be useful; tunneled indwelling catheter another option for treatment

Pleurodesis: obliterating pleural space by fusion of parietal and visceral pleura; success depends on complete inflation of lung to allow apposition of pleura; manual pleurodesis — rough material (eg, gauze or cautery cleaning pad) used to abrade pleura; most commonly used for young patients with spontaneous pneumothorax, to avoid installation of artificial substances; chemical pleurodesis — talc most commonly used; apply via thoracoscopy or as suspension via chest tube; pleurectomy — removal of parietal pleura of chest wall; not commonly used, but effective; indicated in patients with recurrent pneumothoraces even after manual pleurodesis; disadvantage of postoperative pain; may be performed thoracoscopically

Empyema: infection in pleural space; if patient presents acutely ill, drainage most important initial intervention; can often be obtained with chest tube; marsupialization — Clagett window or Eloesser flap; ribs removed and sutures used to create space that remains open to allow drainage; decortication — chest computed tomography (CT) may show complex pleural effusion with peel, which may require decortication; goal of decortication to remove tissue and fibrosis that prevents lung from fully expanding; fibrothorax — even if simple infections can be treated with drainage and antibiotics, can develop fibrothorax, which limits lung function and diaphragmatic excursion

Hemothorax: etiologies include trauma, tumor, infection, and postoperative occurrence after lung or heart surgery; bleeding from trauma usually related to laceration of intercostal or internal mammary artery; lung parenchyma can also be cause (bleeding will often stop spontaneously); diagnosis — usually diagnosed by chest radiography or CT of chest in emergency department (ED); CT useful because lung contusion may mimic fluid; treatment — complete evacuation; inadequate drainage can lead to fibrothorax and to decortication; most bleeding stops and can be managed with chest tube; if hemothorax persists after placement of 2 chest tubes or remains after 48 hr, operative drainage and clearing of clots warranted

Criteria for emergency exploration: immediate drainage of 1500 mL or rate of 250 to 300 mL/hr; may start exploration thoracoscopically if bleeding relatively slow, which enables identification of source of bleeding and evacuation of blood; if bleeding significant, thoracotomy may be best approach

Chylothorax: causes include injury of thoracic duct, infection, and lymphoma; diagnosis supported by presence of semiviscous milky fluid; if triglyceride level >110 mg/dL and lymphocytes constitute 90% of cell count, 99% likelihood of chylous effusion; microscopic presence of chylomicrons confirms diagnosis; management — drainage with chest tube to relieve symptoms; dietary modifications, including enteral medium-chain triglycerides and parenteral nutrition; with this approach 50% will close within 5 to 7 days; chemical pleurodesis may be applied to prevent recurrent effusion; surgical therapy — right thoracotomy approach to diaphragm, with mass ligation of tissue between azygos vein and aorta with goal to ligate thoracic duct; 90% rate of success; other options include pleuroperitoneal shunt and percutaneous embolization

Lung cancer: most common lung cancers non-small cell, including squamous cell, adenocarcinoma, bronchoalveolar, large cell, and adenosquamous; others include carcinoids, which may be benign or atypical (proclivity for nodal metastasis); presentation — sometimes cough or hemoptysis; in speaker’s practice, most present as incidental findings (eg, solitary pulmonary nodules) on CT; suggestion of malignancy include increase in size over time, spiculated margins, air bronchogram, ground-glass opacity, distortion of vascular structures, and increased enhancement with administration of contrast; risk factors — increasing age; smoking; occupational exposures to asbestos, radioactive substances, or heavy metals; living in areas where exposed to radon gas

Workup of solitary pulmonary nodule: check any previous radiography; if nodule unchanged for 2 yr, no further workup necessary; nodule of unknown duration — if low-risk patient and nodule ≤4 mm in size, follow-up probably not necessary; 4 to 6 mm, consider repeat CT in 12 mo; 6 to 8 mm, consider repeat CT in 6 to 12 mo; nodule >8 mm, consider repeat CTs at 3, 9, and 24 mo; if clinical risk high, however, even small nodules should be followed with CT in 12 mo; significant change on subsequent CT requires further evaluation; positron emission tomography (PET) — may be performed, but with caveats that infections also result in increased metabolic activity, and small cancers may yield negative result; if PET positive, needs further evaluation; if PET negative, may consider biopsy based on clinical characteristics or patient history

Staging: T aspect based on tumor size and presence of invasion into mediastinal structures or pleura; nodal status (N) based on location of lymph node involvement; N1 constitutes intraparenchymal nodes, N2 ipsilateral mediastinal nodes, and N3 involves nodes contralateral to primary tumor

Workup: after history and physical examination, usually proceeds directly to CT of chest and abdomen; perform fiber-optic bronchoscopy to ensure no endobronchial lesions; evaluation of mediastinum — with mediastinal adenopathy >1 cm or fluorodeoxyglucose-avid lymph nodes, further investigation required; approach depends on location; transbronchial needle aspiration using endobronchial ultrasonography can be used for certain level 7 nodes; cervical mediastinoscopy useful for reaching levels 2, 4, and 7; anterior mediastinoscopy or thoracoscopy useful for evaluating levels 5 and 6 on left side

Staging and treatment: surgery considered treatment of choice for stage I and II cancers; for certain stage II tumors, oncologists may recommend postoperative chemotherapy; some stage III tumors (eg, positive ipsilateral mediastinal nodes, certain large tumors with N1 disease, and tumors invading mediastinal structures) potentially resectable; in some patients with stage IIIA disease (eg, microscopic local invasion), neoadjuvant chemotherapy and radiation and subsequent resection may be advantageous; unsuspected mediastinal disease — some patients with clinical stage I or II upgraded at time of surgery when mediastinal lymph node dissection performed; resection and postoperative chemotherapy and radiation improves survival in some patients compared to chemoradiation alone; no role for surgery for stage IIIB tumors (metastases to contralateral mediastinal nodes)

Metastatic tumors of lung: common metastases to lung include colon, renal cell, breast, soft tissue sarcomas, osteogenic sarcoma, melanoma, and germ cell tumors; resection of metastatic colon and renal cell has better long-term outcomes compared to other cell types; resectability most important criterion; if disease-free interval between treatment of primary tumor and discovery of metastasis >36 mo, chance of success of metastasectomy higher; removal of >3 metastases negatively correlates with long-term survival; evaluation — obtain high-resolution CT with 3 to 5 mm slices within 4 wk of surgery to ensure no additional metastases have developed; bronchoscopy appropriate; all nodules should be identified before resection; surgical technique — mediastinal lymph nodes should be sampled (particularly important in resection of colonic metastases); operation of choice usually wedge resection with 1 to 2 cm margin; central tumors may require lobectomy, but perform only with high probability of survival benefit

Tracheoesophageal fistulas in adults: most common causes tumors (trachea, bronchi, or esophagus) and prolonged intubation; presentation includes acute abdominal distention, difficulty with ventilation, loss of return of ventilated breaths, and bilious secretions; diagnosis made by bronchoscopy (important in determining anatomic location) and esophagoscopy; treatment — stabilize and protect airway; decompress gut; determined by location and etiology; if caused by malignancy, poor short-term survival and usually not treated surgically, but may be treated by insertion of stent of esophagus which can prevent contamination of airway; surgical repair may require resection of trachea and esophagus; for fistulas secondary to prolonged intubation, repair performed before removal from mechanical ventilation carries high chance of failure; if associated with tracheostomy, may attempt removal of tracheostomy, placement of longer endotracheal tube, and then weaning from mechanical ventilation before repair; prevention of fistulas during prolonged ventilation — use low-pressure broad cuffs and soft nasoenteric tubes

Tracheoinnominate fistulas: anatomy of innominate artery predisposes to fistula (artery originates anterior to trachea, crosses over it and to right, with minimal soft tissue separation); factors leading to fistula include balloon compression of tracheostomy tube and tracheostomy made too low; usually occurs few weeks after tracheostomy and heralded by sentinel bleeding, although most bleeding from tracheostomy caused by erosions of tracheostomy tract; however, after few weeks, tract should be healed, and bleeding should arouse suspicion of fistula; ideally diagnosed by bronchoscopy before massive bleeding (best performed in operating room [OR]); if presents with massive bleeding, every attempt should be made to control bleeding to allow transport to OR; measures include hyperinflation of cuff or removal of tracheostomy and placement of orotracheal tube with manual compression of artery through tracheostomy hole; treatment — involves division and ligation of artery and repair of trachea (often requiring resection); repair may need to be performed on cardiopulmonary bypass; generally no role for stenting; prevention — tracheostomy should not be placed below third tracheal ring; adequate soft tissue should be preserved above sternal notch; avoid excessive traction and overinflation of cuff

Indications for surgical exploration of the traumatized thoracic cavity: in general, thoracotomy in ED not productive; however, in select circumstances may be life saving (eg, pericardial tamponade); indicated for laceration of lung if unable to ventilate patient; may require resection, oversewing, or stapling; tracheobronchial injury — consider diagnosis in presence of large air leak or difficulty ventilating patient; perform bronchoscopy to confirm injury prior to performing any intervention; esophageal injury — should be repaired primarily; injuries to heart, great vessels, or mediastinum — require sternotomy

Approaches to exploration of thorax: more procedures now performed with minimally invasive approaches; open approach more appropriate for large tumors and with difficulty obtaining vascular control; if performing thoracotomy for trauma, best approach probably lateral or posterolateral incision in fifth intercostal space, which can be carried behind scapula

Partial pulmonary resection: segmentectomy or wedge resection may be appropriate for diagnosis or for treating metastases; resection for cancer — preserve lung tissue without violating oncologic principles (eg, strive for 2 cm parenchymal margin); wedge resections may be appropriate therapy for some patients with poor pulmonary function and peripheral nodules; segmentectomy able to capture lymphatic drainage; sentinel lymph node at apex of parenchymal triangle should be biopsied to ensure absence of metastatic disease; lobectomy required if nodal metastasis present; for small tumors, survival after segmentectomy similar to that with lobectomy; wedge resection may have slightly higher chance of local recurrence; partial pulmonary resection carries higher incidence of air leak, because cutting across parenchyma rather than fissures; segmentectomy generally good option for small tumors, particularly in patients with limited lung function

Pericardial effusion: most not life-threatening and can be followed and observed; progression to tamponade primary problem; symptoms of tamponade include hemodynamic compromise, and may be subtle, eg, fatigue, dyspnea, tachycardia, reduced urine output; diagnosis by echocardiography; treatment — percutaneous drainage sometimes useful, but may have higher incidence of recurrence; surgical approaches either subxiphoid or thoracoscopic; should include removal of square of pericardium to prevent recurrence

Readings

Disclosures

In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning committee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial interest. For this program, Dr. Savage and the planning committee reported nothing to disclose.

Acknowledgements

Dr. Savage was recorded from Audio Digest General Surgery Board Review. For more information about Audio Digest General Surgery Board Review, please visit our website, Audio-Digest.org. The Audio Digest Foundation thanks the speaker for his cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

GS620601

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.

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