Chapter 25 - Thoracic++ Flashcards
What is the path of the azygos vein?
Runs along the right side and dumps into superior vena cava in the superior chest
What is the path of the thoracic duct?
Runs along the right side, crosses midline and dumps into left SCV at junction with IJ
Which mainstem bronchi is longer?
Left
Which pulmonary artery is longer?
Right
Which nerve runs anterior to hilum? Which runs posterior to hilum?
Anterior – phrenic; posterior – vagus
What percentage of total lung volume is the right lung volume? What is the left lung volume?
55%; 45%
What percent of the work is done by the diaphragm during quiet inspiration?
80%
What are the accessory muscles of respiration?
Sternocleidomastoid, levators, serratus posterior, scalenes
What is the function of type I pneumocyte? Type II pneumocytes?
Type I: gas exchange; type II: surfactant production
What is the purpose of pores of Kahn?
Direct air exchange between alveoli
What FEV1 is needed before surgery?
Greater than 0.8L or 40% of predicted value
What value of pCO2 or CO2 is needed prior to resection?
pCO2 greater than 45, CO2 less than 50. This is not an absolute contraindication in itself, but it likely correlates w/ a poor FEV1 or poor exercise performance.
Persistent air leak is most common after what operation?
Segmentectomy, wedge
Symptoms of lung cancer?
Most common symptom is persistent cough.
Asymptomatic with findings on routine chest x-ray, pneumonia, pain, weight loss.
What is the most common cause of cancer related death in the United States?
Lung cancer
What aspect of lung cancer has the strongest influence on survival?
Nodal involvement
What is the single most common site of lung cancer metastasis?
Brain
How does lung cancer recurrence present? What percent of recurrences are within the first three years?
Most commonly appears as disseminated metastases; 80%
What is the overall five-year survival rate of lung cancer? With resection?
10%; 30%
Which stages of lung cancer are resectable?
Stage I and II
What is the most common lung cancer?
Adenocarcinoma
What percent of lung cancer is non-small cell carcinoma?
80%
What type of non-small cell carcinoma is associated with more peripheral lesions and distant metastases?
Adenocarcinoma - described as ground-glass and hazy appearing
What type of non-small cell carcinoma is associated with local recurrence and more central lesions?
Squamous cell carcinoma - spiculated and irregular appearing, cavitation with resultant central scar
What percent of lung cancer is small cell carcinoma?
20%
- bulky nodal disease can be a diagnostic clue
- often has distant mets
- more commonly have paraneoplastic syndromes
- manage like NSCLC if presents as SPN
What is the overall five-year survival rate for small cell carcinoma?
- Very poor, less than 5% are candidates for surgery.
- 10-13% for limited disease and 1-2% for extensive disease.
What paraneoplastic syndrome is associated with squamous cell carcinoma?
What two are associated with small cell carcinoma? Which is most common?
Squamous cell – PTH related peptide
Small cell – ACTH (most common), ADH
What is the most malignant lung tumor?
Mesothelioma
- extrapleural pneumonectomy best achieves local control
- higher recurrence-free survival
- no difference in overall survival, however
- chemo or radx is not a first choice tx
Chemotherapy used for non-small cell carcinoma stage II or higher?
Carboplatin, Taxol
What chemotherapy is used for small cell lung cancer?
Cisplatin, etoposide
What findings would prompt use of mediastinoscopy?
Centrally located tumors, patients with suspicious adenopathy, ipsilateral and contralateral mediastinal nodes
What is the Chamberlain procedure?
- mediastinoscopy through L 2nd rib cartilage
- aortopulmonary window nodes (station 5/6)
- LUL cancers go through these nodes, but cannot often be reached by other MIS methods
- used to stage these cancers if suspected nodes in this area
- EBUS is first for central tumors/nodes
- percutaneous is first for peripheral
What is a Pancoast tumor (aka superior sulcus tumor)?
Tumor invades apex of chest wall and patients have Horner’s syndrome or ulnar nerve symptoms
- eval for brachial plexus involvement: contraindx to surg if extensive
- mediastinoscopy: eval for mediastinal nodes
- nodes involved: no resection (N2)
- uninvolved: en-bloc resection, don’t resect brachial plexus, ok to resect sympathetic chain, chest wall involvement likely (often involves ribs 2-4)
Which cancers’ mets to the lung may be resected if isolated and not associated with any other systemic disease?
Colon, renal cell cancer, sarcoma, melanoma, ovarian or endometrial cancer
What are the characteristics of a carcinoid tumor?
Neuroendocrine tumor, central, 50% with symptoms
What is the five-year survival of a typical carcinoid? Atypical carcinoid?
90%, 60%
What bronchial adenomas are malignant?
Adenoid cystic adenoma, mucoepidermoid adenoma, mucous gland adenoma
What is the spread of adenoid cystic adenoma?
Spread along perineural lymphatics, beyond endoluminal compartment; slow-growing, can get 10 year survival with incomplete resection
What is the most common benign adult lung tumor?
- Hamartomas - 75% of all benign tumors. Men > women.
- PSX: SPN w/ very slow growth
- DX: well-circumscribed nodule w/ popcorn calcification; needle aspx
- TX: if symptomatic, resect
What do hamartoma lesions look like on chest CT?
Have calcifications, appear as popcorn lesion, with fat within the lesion
Do hamartomas require resection?
No; repeat chest CT in six months to confirm diagnosis
What is the most common mediastinal tumor in adults and children?
Neurogenic
What is the most common site for mediastinal tumor?
Anterior
What tumors can be found in the anterior mediastinum?
Lots of “Ts”:
- Thymoma
- Thyroid cancer
- paraThyroid adenoma
- T-cell lymphoma
- Teratoma
What is the number one anterior mediastinal mass in adults?
Thymoma
What tumors can be found in the middle mediastinum?
Lots of cysts:
- bronchiogenic cyst
- pericardial cyst
- enteric cyst
- lymphoma
What tumors can be found in the posterior mediastinum?
Enteric cyst, neurogenic tumor, lymphoma
What percent of thymomas are malignant? What percent have symptoms? What percent are associated with myasthenia gravis?
50%, 50%, 50%
What percent of patients with myasthenia gravis have thymomas?
10%
Treatment of thymomas?
- All need resection (may include pericardium or lung)
- Neoadj chemo if not/potentially resectable
- Stage II or III requires postop RT
- (thymic cancer always requires PORT)
- If myasthenia gravis, tx preop: anti-cholinesterase medications, plasmapheresis, steroids
What is the most common type of lymphoma?
T cell non-Hodgkin’s lymphoma
What type of Hodgkin’s lymphoma is most common?
Nodular sclerosing
What is the treatment for lymphoma?
Chemo and radiation
What is the most common germ cell tumor in the mediastinum? What is the most common malignant germ cell tumor in the mediastinum?
Teratoma, seminoma
Treatment for germ cell tumors?
- Sx: due to mass effect
- Dx: AFP, b-HCG; CT
- Tx mature teratoma: resection (sternotomy or post/lat thoracotomy); relatively insensitive to chemo/radx
- Tx immature teratoma: neoadj chemo and resx
- Tx seminoma: platinum based chemo and radx, can resect small ones
What percent of nonseminoma tumors have elevated beta hCG and alpha-fetoprotein?
90%
What are bronchiogenic cysts? Where are bronchiogenic cysts? What is their treatment?
- Arise from anomalous budding of the foregut.
- Psx: 20 yr w/ hard to tx coughing, wheezing, PNA
- Dx: CXR shows air-fluid lvl if infx, CT demonstrates cystic nature; do not communicate w/ bronchial tree
- Posterior to carina in middle medx`iastinum
- Tx: Partial or total lobectomy - likely to be symptomatic, can become malignant
Where are pericardial cyst found? What is their treatment?
- At right cardiophrenic angle
- Psx: SoB, R HF; asx incidental finding
- Tx: resection if sx or unsure of dx, can be observed if found incidentally and asx
What is the most common neurogenic tumor? Treatment?
Neurolemmoma, resection
Paragangliomas produce what?
Catecholamines
Nerve sheath tumors are associated with what syndrome?
- Von Recklinghausen’s, AKA NF1
- cafe-au-lait spots, cutaneous neurofibromas, Lisch nodules, axillary/inguinal freckling
- autosomal dominant, neurofibromin
- mediastinal neurofibromas are very rare
What percent of symptomatic mediastinal masses are malignant?
50%
What percent of asymptomatic mediastinal masses are benign?
90%
What are benign tumors of the trachea in adults? children?
Adults – papilloma, children – hemangioma
What are malignant tumors of the trachea?
Squamous cell carcinoma
What is the most common early complication after tracheal surgery? Late?
Laryngeal edema; granulation tissue formation
Where is post-intubation stenosis?
At stoma site with tracheostomy, at cuff with ET tube
Where does a tracheostomy need to be placed so as not to risk tracheoinnominate fistula?
Between the first and second tracheal rings, not lower than third rings
Treatment for tracheoinnominate fistula?
- overinflated balloon or stick your finger in the tracheotomy and compress the innominate
- resect innominate and place graft
- use new tracheostomy site
Management of benign tracheoesophageal fistula?
- Hx: large bore NGT/ETT/trach for long period, perc trach
- Sx: aspiration, cuff leak, bile/saliva from ETT, recurrent/persistent PNA
- Dx: swallow study or CT w/ panendoscopy
- Tx: NPO, decompress stomach, elevate HoB, define size
- stent can temporize, DC causing agent
- clip for poor OR candidate
- small: divide and repair w/ covering over NGT
- large: +/- decompressing gastrostomy
- +/- tracheal resection, recon
- +/- sternohyoid flap
- may require delayed repair
Lung abscesses are most commonly associated with what? What segment of the lung are they most commonly in?
Aspiration; posterior segment of RUL and superior segment of RLL
Treatment for lung abscess?
- Antibiotics that include anaerobe coverage are 95% successful. Can take months.
- CT guided drain if meds fail.
- Surgery if drain fails or cannot rule out cancer. Usually not needed.
What causes empyemas?
Secondary to pneumonia and subsequent parapneumonic effusion (staph, strep)
Symptoms of empyema?
Pleuritic chest pain, fever, cough, SOB
What will the pleural fluid show in empyema?
WBCs >500 cells/cc, bacteria, positive G stain
3 phases of empyema?
Exudative (1st week), fibroproliferative phase (2nd week), Organized phase (3rd week)
Treatment of empyema in the exudative phase?
- Uncomplicated parapneumonic effusions can be tx w/ thoracentesis
- Otherwise, chest tube w/ flushes
- Abx to include anaerobes
- CT w/in 24 hrs
- remove when draining <50ml/day
- failure requires VATS
Treatment of empyema in organized phase?
Likely decortication of fibrous peel around lung causing failure of re-expansion. Usually not needed unless pleural restriction present after 6 months.
More adhesions, larger pleural thickness, larger cavity may favor open decortication.
What is an Eloesser flap?
Direct opening to external environment
Chylothorax fluid characteristics?
Milky white; high lymphocytes and TAGs (>110), Sudan red stains fat. Will also have high lymphocytes w/ normal pH.
What is the cause of chylothorax?
50% trauma/iatrogenic injury to thoracic duct, 50% tumor (lymphoma most common)
What level injury causes left sided chylothorax? Right sided?
Thoracic duct injury:
- Left: above T5-6
- Right: below T5-6
Treatment for chylothorax?
3-4wk conservative: CTb, octreotide, low-fat diet or TPN; if fails: surgery with ligation of thoracic duct on R. low in mediastinum
What is considered massive hemoptysis?
>600cc/24h
What is the bleeding from in massive hemoptysis?
High pressure bronchial arteries
What is the most common etiology of massive hemoptysis?
In US, 2/2 bronchectasis from CF.
In devloping countries, 2/2 TB.
Cancer and aspergilloma are other causes.
Treatment of massive hemoptysis?
- place bleeding side down
- OR rigid bronch to ID side and tx if possible
- consider angio if unable to ID bleeding side
- mainstem intubation to side opposite bleeding
- no go: FEV <40% predicted, unable to localize, unresectable cancer/metastasis, coagulopathy, bilateral
- OR for lobectomy or pneumonectomy
- bronchial artery embolization if not good for OR
What is the recurrence risk of spontaneous pneumothorax after 1st? 2nd? 3rd?
1st: 20%, 2nd: 60%, 3rd: 80%
Treatment for spontaneous pneumothorax?
When is surgical intervention warranted?
Chest tube
Surgery for recurrence, large blebs on CT, air leak >7d, nonreexpansion
What does surgery for spontaneous pneumothorax entail?
Thoracoscopy, apical blebectomy, mechanical pleurodesis
What are bronchiogenic cysts?
Abnormal lung tissue outside lung; did not get connected to bronchial system
Where does sequestered lung tissue get its blood supply?
From anomalous systemic arteries, usually off of thoracic aorta; can also come from abdominal aorta through inferior pulmonary ligament
Who is extralobar sequestration more common in?
Children; more likely to have systemic venous drainage
Who is intralobar sequestration more common in?
Adults; more likely to have pulmonary vein drainage
Treatment for sequestration?
Lobectomy
What condition is most likely to cause arrest after blunt trauma due to impaired venous return?
Tension pneumothorax
What is a catamenial pneumothorax and what is it caused by?
Occurs in temporal relation to menstruation, caused by endometrial implants in the visceral lung pleura
What are bronchioliths usually caused by?
Secondary to infection
When does mediastinitis usually occur?
After cardiac surgery
What causes white out on chest x-ray with midline shift toward white out? Midline shift away from white out? No shift?
Toward whiteout: collapse from obstruction, need bronchoscopy to remove plug
Away: effusion, place chest tube
No shift: possibly contusion w/ trauma hx; CT to figure out