– Thoracic

Azygous vein runs along the right side and dumps into superior vena cava

Thoracic duct runs along the right side, crosses midline at T4–5, and dumps into left subclavian vein at junction with internal jugular vein

Phrenic nerve – runs anterior to hilum

Vagus nerve – runs posterior to hilum

Right lung volume 55% (3 lobes: RUL, RML, and RLL)

Left lung volume 45% (2 lobes: LUL and LLL and lingula)

Quiet inspiration – diaphragm 80%, intercostals 20%

Greatest change in dimension superior/inferior

Accessory muscles – sternocleidomastoid muscle (SCM), levators, serratus posterior, scalenes

Type I pneumocytes – gas exchange

Type II pneumocytes – surfactant production

Pores of Kahn – direct air exchange between alveoli

PULMONARY FUNCTION TESTS

Need predicted postop FEV₁ > 0.8 (or > 40% of the predicted postop value)

• If it is close → get qualitative V/Q scan to see contribution of that portion of lung to overall FEV₁ → if low, may still be able to resect

Need predicted postop DLCO > 10 mL/min/mm Hg CO (or > 40% of the predicted postop value)

• Measures carbon monoxide diffusion and represents oxygen exchange capacity

• This value depends on pulmonary capillary surface area, hemoglobin content, and alveolar architecture

No resection if preop pCO₂ > 50 or pO₂ < 60 at rest

No resection if preop VO₂ max < 10–12 mL/min/kg (maximum oxygen consumption)

Persistent air leak – most common after segmentectomy/wedge

Atelectasis – most common after lobectomy

Arrhythmias – most common after pneumonectomy

LUNG CANCER

Symptoms: can be asymptomatic with finding on routine CXR; cough, hemoptysis, atelectasis, PNA, pain, weight loss

Most common cause of cancer-related death in the United States

Nodal involvement has strongest influence on survival

Brain – single most common site of metastasis

• Can also go to supraclavicular nodes, other lung, bone, liver, and adrenals

Recurrence usually appears as disseminated metastases

• 80% of recurrences are within the 1st 3 years

Lung CA overall 5-year survival rate 10%; 30% with resection for cure

Stage I and II disease resectable; T3,N1,M0 (stage IIIa) possibly resectable

Lobectomy or pneumonectomy most common procedure; sample suspicious nodes

Non–small cell carcinoma

• 80% of lung CA

• Squamous cell carcinoma usually more central

• Adenocarcinoma usually more peripheral

• Adenocarcinoma is the most common lung CA (not squamous)

TNM STAGING SYSTEM FOR LUNG CANCER

• T1: < 3 cm. T2: > 3 cm but > 2 cm away from carina. T3: invasion of chest wall, pericardium, diaphragm, or < 2 cm from carina. T4: mediastinum, esophagus, trachea, vertebra, heart, great vessels, malignant effusion (all indicate unresectability)

• N1: ipsilateral hilum nodes. N2: ipsilateral mediastinal or subcarinal (unresectable).

• N3: contralateral mediastinal or supraclavicular (unresectable)

• M1: distant metastasis

Small cell carcinoma

• 20% of lung CA; neuroendocrine in origin

• Usually unresectable at time of diagnosis (< 5% candidates for surgery)

• Overall 5-year survival rate < 5% (very poor prognosis)

• Stage T1,N0,M0 5-year survival rate – 50%

• Most get just chemo-XRT

Paraneoplastic syndromes

• Squamous cell CA – PTH-related peptide

• Small cell CA – ACTH and ADH

• Small cell ACTH – most common paraneoplastic syndrome

Mesothelioma

• Most malignant lung tumor

• Aggressive local invasion, nodal invasion, and distant metastases common at the time of diagnosis

• Asbestos exposure

Non–small cell CA chemotherapy (stage II or higher) – carboplatin, Taxol

Small cell lung CA chemotherapy – cisplatin, etoposide

XRT can be used for lung CA as well

Chest and abdominal CT scan – single best test for clinical assessment of T and N status

PET scan – best test for M status

Mediastinoscopy

• Use for centrally located tumors and patients with suspicious adenopathy (> 0.8 cm or subcarinal > 1.0 cm) on chest CT

• Does not assess aorto-pulmonary (AP) window nodes (left lung drainage)

• Assesses ipsilateral (N2) and contralateral (N3) mediastinal nodes

• If mediastinal nodes are positive, tumor is unresectable

• Looking into middle mediastinum with mediastinoscopy

• Left-side structures – RLN, esophagus, aorta, main pulmonary artery (PA)

• Right-side structures – azygous and SVC

• Anterior structures – innominate vein, innominate artery, right PA

Chamberlain procedure (anterior thoracotomy or parasternal mediastinotomy) – assesses enlarged AP window nodes; go through left 2nd rib cartilage

Bronchoscopy – needed for centrally located tumors to check for airway invasion

For lung CA, patients need to 1) be operable (eg have appropriate FEV₁ and DLCO values) and 2) be resectable (ie can’t have T4, N2, N3, or M disease)

Pancoast tumor – tumor invades apex of chest wall and patients have Horner’s syndrome (invasion of sympathetic chain → ptosis, miosis, anhidrosis) or ulnar nerve symptoms

Coin lesion

• Overall, 10% are malignant

• Age < 50 → < 5% malignant; age > 50 → > 50% malignant

• No growth in 2 years, and smooth contour suggests benign disease

• If suspicious, will need either guided biopsy or wedge resection

Asbestos exposure increases lung CA risk 90X

Bronchoalveolar CA – can look like pneumonia; grows along alveolar walls; multifocal

Metastases to the lung – if isolated and not associated with any other systemic disease, may be resected for colon, renal cell CA, sarcoma, melanoma, ovarian, and endometrial CA

CARCINOIDS

Neuroendocrine tumor, usually central

• 5% have metastases at time of diagnosis; 50% have symptoms (cough, hemoptysis)

Typical carcinoid – 90% 5-year survival rate

Atypical carcinoid – 60% 5-year survival

Tx: resection; treat like cancer; outcome closely linked to histology

Recurrence increased with positive nodes or tumors > 3 cm

BRONCHIAL ADENOMAS

Mucoepidermoid adenoma, mucous gland adenoma, and adenoid cystic adenoma → all are malignant tumors

Mucoepidermoid adenoma and mucous gland adenoma

• Slow growth, no metastases

• Tx: resection

Adenoid cystic adenoma

• From submucosal glands; spreads along perineural lymphatics, well beyond endoluminal component; very XRT sensitive

• Slow growing; can get 10-year survival with incomplete resection

• Tx: resection; if unresectable, XRT can provide good palliation

HAMARTOMAS

Most common benign adult lung tumor

Have calcifications and can appear as a popcorn lesion on chest CT

Diagnosis can be made with CT

Do not require resection

Repeat chest CT in 6 months to confirm diagnosis

MEDIASTINAL TUMORS IN ADULTS

Most are asymptomatic; can present with chest pain, cough, dyspnea

Neurogenic tumors – most common mediastinal tumor in adults and children, usually in posterior mediastinum

50% of symptomatic mediastinal masses are malignant

90% of asymptomatic mediastinal masses are benign

Location

• Anterior (thymus) – most common site for mediastinal tumor; T’s →

• Thymoma (#1 anterior mediastinal mass in adults)

• Thyroid CA and goiters

• T-cell lymphoma

• Teratoma (and other germ cell tumors)

• Parathyroid adenomas

• Middle (heart, trachea, ascending aorta)

• Bronchiogenic cysts

• Pericardial cysts

• Enteric cysts

• Lymphoma

• Posterior (esophagus, descending aorta)

• Enteric cysts

• Neurogenic tumors

• Lymphoma

Thymoma

• All thymomas require resection

• Thymus too big or associated with refractory myasthenia gravis → resection

• 50% of thymomas are malignant

• 50% of patients with thymomas have symptoms

• 50% of patients with thymomas have myasthenia gravis

• 10% of patients with myasthenia gravis have thymomas

Myasthenia gravis – fatigue, weakness, diplopia, ptosis; antibodies to acetylcholine receptors

• Tx: anticholinesterase inhibitors (neostigmine); steroids, plasmapheresis

• 80% get improvement with thymectomy, including patients who do not have thymomas

Germ cell tumors

• Need to biopsy (often done with mediastinoscopy)

• Teratoma – most common germ cell tumor in mediastinum

• Can be benign or malignant

• Tx: resection; possible chemotherapy

• Seminoma – most common malignant germ cell tumor in mediastinum

• 10% are beta-HCG positive; should not have AFP (alpha-fetoprotein)

• Tx: XRT (extremely sensitive); chemotherapy reserved only for metastases or bulky nodal disease; surgery for residual disease after that

• Non-seminoma – 90% have elevated beta-HCG and AFP

• Tx: chemo (cisplatin, bleomycin, VP-16); surgery for residual disease

Cysts

• Bronchiogenic – usually posterior to carina. Tx: resection

• Pericardial – usually at right costophrenic angle. Tx: can leave alone (benign)

Neurogenic tumors – have pain, neurologic deficit. Tx: resection

• 10% have intra-spinal involvement that requires simultaneous spinal surgery

• Neurolemmoma (schwannoma) – most common

• Paraganglioma – can produce catecholamines, associated with von Recklinghausen’s disease

• Can also get neuroblastomas and neurofibromas

TRACHEA

Benign tumors: adults – papilloma; children – hemangioma

Malignant – squamous cell carcinoma

Most common late complication after tracheal surgery – granulation tissue formation

Most common early complication after tracheal surgery – laryngeal edema

• Tx: reintubation, racemic epinephrine, steroids

Post-intubation stenosis – at stoma site with tracheostomy, at cuff site with ET tube

• Serial dilatation, bronchoscopic resection, or laser ablation if minor

• Tracheal resection with end-to-end anastomosis if severe or if it keeps recurring

Tracheo-innominate artery fistula – occurs after tracheostomy, can have rapid exsanguination

• Tx: place finger in tracheostomy hole and hold pressure → median sternotomy with ligation and resection of innominate artery

• This complication is avoided by keeping tracheostomy above the 3rd tracheal ring

Tracheo-esophageal fistula

• Usually occurs with prolonged intubation

• Place large-volume cuff endotracheal tube below fistula

• May need decompressing gastrostomy

• Attempt repair after the patient is weaned from ventilator

• Tx: tracheal resection, reanastomosis, close hole in esophagus, sternohyoid flap between esophagus and trachea

LUNG ABSCESS

Necrotic area; most commonly associated with aspiration

Most commonly in the superior segment of RLL

Tx: antibiotics alone (95% successful); CT-guided drainage if that fails

• Surgery if above fails or cannot rule out cancer (> 6 cm, failure to resolve after 6 weeks)

Chest CT can help differentiate empyema from lung abscess

EMPYEMA

Usually secondary to pneumonia and subsequent parapneumonic effusion (staph, strep)

Can also be due to esophageal, pulmonary, or mediastinal surgery

Symptoms: pleuritic chest pain, fever, cough, SOB

Pleural fluid often has WBCs > 500 cells/cc, bacteria, and a positive Gram stain

Exudative phase (1st week) – Tx: chest tube, antibiotics

Fibro-proliferative phase (2nd week) – Tx: chest tube, antibiotics; possible VATS (video-assisted thoracoscopic surgery) deloculation

Organized phase (3rd week) – Tx: likely need decortication; fibrous peel occurs around lung

• Some are using intra-pleural tPA (tissue plasminogen activator) to try and dissolve the peel

• May need Eloesser flap (open thoracic window – direct opening to external environment) in frail/elderly

CHYLOTHORAX

Milky white fluid; has ↑ lymphocytes and TAGs (> 110 mL/µL); Sudan red stains fat

Fluid is resistant to infection

50% secondary to trauma or iatrogenic injury

50% secondary to tumor (lymphoma most common, due to tumor burden in the lymphatics)

Injury above T5–6 results in left-sided chylothorax

Injury below T5–6 results in right-sided chylothorax

Tx: 2–3 weeks of conservative therapy (chest tube, octreotide, low-fat diet or TPN)

• If above fails and chylothorax secondary to trauma or iatrogenic injury, need ligation of thoracic duct on right side low in mediastinum (80% successful)

• For malignant causes, need talc pleurodesis and possible chemo and/or XRT (less successful than above)

MASSIVE HEMOPTYSIS

> 600 cc/24 h; bleeding usually from high-pressure bronchial arteries

Most commonly secondary to infection, death is due to asphyxiation

Tx: place bleeding side down; mainstem intubation to side opposite of bleeding to prevent drowning in blood; rigid bronchoscopy to identify site and possibly control bleeding; may need lobectomy or pneumonectomy to control; bronchial artery embolization if not suitable for surgery

SPONTANEOUS PNEUMOTHORAX

Tall, healthy, thin, young males; more common on the right

Recurrence risk after 1st pneumothorax is 20%, after 2nd pneumothorax is 60%, after 3rd pneumothorax is 80%

Results from rupture of a bleb usually in the apex of the upper lobe of the lung

Tx: chest tube

Surgery for recurrence, air leak > 7 days, non-reexpansion, high-risk profession (airline pilot, diver, mountain climber), or patients who live in remote areas