Thoracic Flashcards
Azygos vein
runs along right side and dumps into SVC
Thoracic duct
runs along right side, crosses midline, and dumps into left subclavian vein at junction with internal jugular vein; crosses at T4-T5
Mainstem bronchus
left longer than right
Pulmonary artery
right longer than left before 1st branch
Phrenic nerve
runs anterior to hilum
Vagus nerve
runs posterior to hilum
Lung volume
- right lung 55% 3 lobes (RUL, RML, RLL)
* left lung 45% 2 lobes (LUL and LLL and lingula)
Quiet inspiration
- diaphragm 80%, intercostals 20%
- greatest change in dimension superior / inferior
- accessory muscles - sternocleidomastoid muscle, levators, serratus posterior, scalenes
Type 1 pneumocytes
gas exchange
Type 2 pneumocytes
surfactant production
Pores of Kahn
direct air exchange between alveoli
Pleural fluid
1-2 L / day; parietal pleura produces pleural fluid cleared by lymphatics in visceral pleura
Pulmonary Function Tests
- need predicted postop FEV1 > 0.8 (or at least 40% of predicted value)
- if 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 > 11-12 mL/min/mm Hg CO (at least 50% of predicted value); this represents CO diffusion capacity; this value is based on pulmonary capillary surface area, Hgb content, and alveolar architecture
- need predicted postop FVC > 1.5L
- no resection if pre op pCO2 > 45 or pO2 < 50 at rest
- no resection if preop VO2 max < 10 mL/min/kg
Persistent air leak
most common after segmentectomy / wedge
Atelectasis and arrhythmias
common problems after lobectomy or pneumonectomy
Lung cancer
- most common cause of cancer related death in US
- nodal involvement has strongest influence on survival
- Brain single most common site of mets
- can also go to supraclavicular nodes, other lung, bone, liver, and adrenals
- Recurrence most commonly appears as disseminated mets (brain most common)
- 80% recurrences are within the 1st 3 yrs
- over 5y survival rate 10%; 30% with resection
- stage I and II resectable; T3N1M0 (IIIa) possibly resectable
- adenocarcinoma most common lung ca
Non small cell carcinoma
- 80% of lung ca
- squamous cell ca usually more central
- adenocarcinoma usually more peripheral
- local recurrence increased with squamous cell ca
- distant mets increased with adenoca
- chemo stage II or higher - carboplatin, taxol
TNM staging for lung cancer
T1: < 3cm
T2: > 3cm but > 2cm away from carina
T3: invasion of chest wall, pericardium, diaphragm or < 2cm from carina
T4: mediastinum, esophagus, trachea, vertebra, heart, great vessels, malignant effusion (all indicate unresectable)
N1: ipsilateral hilum nodes
N2: ipsilateral mediastinal nodes (unresectable)
N3: contralateral mediastinal or supraclavicular nodes (unresectable)
M1: distant mets
Small cell carcinoma
- 20% lung CA neuroendocrine in orign
- usually unresectable at time of dx (<5% candidates for surgery)
- overall 5-yr survival rate; very poor px
- stage T1, N0, M0 5 year survival rate - 50%
- most get chemo and XRT
- chemo - cisplatin, etoposide
Squamous cell CA paraneoplastic syndrome
PTH-related peptide
Small Cell CA paraneoplastic syndrome
ACTH, ADH
*ACTH most common paraneoplastic syndrome
mesothelioma
most malignant lung tumor
- aggressive local invasion, nodal invasion, and distant mets common at the time of dx
- asbestos exposure
Mediastinoscopy
- use for centrally located tumors and pts with suspicious adenopathy > 0.8cm or subcarinal > 1.0cm on chest ct
- does not assess aortopulmonary window nodes (left lung drainage)
- assesses ipsilateral (N2) and contralateral (N3) mediastinal nodes
- if positive, tumor unresectable
- looking into middle mediastinum with mediastinoscopy:
- left sided structures - RLN, esophagus, aorta, main PA
- right sided structures - azygous & SVC
- anterior structures - innominate vein, innominate artery, right PA
Chamberlain procedure
assesses aortopulmonary window nodes; go through left 2nd rib cartilage
Bronchoscopy
needed for centrally located tumors
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 5-10% are malignant
- age < 50 –> < 5% malignant
- age > 50 –> > 50% malignant
- no growth in 2 years, smooth contour suggests benign disease
- core needle biopsy frequently nondiagnostic
Asbestos exposure
increases lung CA risk 90x
Bronchioalveolar CA
can look like PNA; grows along alevolar walls, multifocal
Mets to lung
if isolated and not associated with any other systemic disease, may be resected for colon, renal cell CA, sarcoma, melanoma, ovarian, or endometrial CA
Carcinoids
neuroendocrine tumor, usually central
- 5% have mets at time of dx; 50% have symptoms
- 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 > 3cm
Malignant bronchial adenomas
adenoid cystic adenoma, mucoepidermoid adenoma, mucous gland adenoma
- slow growth, no mets
- tx: resection
Adenoid cystic adenoma
- submucosal glands; spread along perineural lymphatics, well beyond endoluminal component; 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
- dx can be made with CT
- do not require resection
- repeat Chest CT in 6 months to confirm diagnosis
Neurogenic tumors
most common mediastinal tumor in adults and children, usually posterior mediastinum
Anterior mediastinal tumors (thymus)
- most common site for mediastinal tumor
- thymoma (#1 in adults)
- thyroid cancer and goiters
- T cell lymphoma
- teratoma (germ cell tumors)
- parathyroid adenomas
Middle mediastinal tumors (heart, trachea, ascending aort)
- bronchogenic cysts
- pericardial cysts
- enteric cysts
- lymphoma
Posterior mediastinal tumors (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 have symptoms
- 50% pts have myasthenia gravis
- 10% pts with myasthenia gravis have thymomas
Myasthenia gravis
fatigue, weakness, diplopia, ptosis, antibodies to acetylcholine receptors
- tx: anticholinesterase medications, plasmapheresis, steroids
- 80% get improvement with thymectomy, including patients who do not have thymomas
Lymphoma
- T cell most common (non-Hodgkins) - lymphoblastic variant most common
- Hodgkin’s lymphoma - nodular sclerosing most common
- Tx: chemo and XRT
Germ cell tumors
- need to biopsy (usually via mediastinoscopy)
- teratoma –> most common germ cell tumor in mediastinum; tx: resection and chemo
- seminoma –> most common malignant germ cell tumor in mediastinum; tx: XRT (extremely sensitive); chemo for positive nodes or residual disease; surgery for residual disease after that
- nonseminoma –> 90% have elevated beta-HCG and AFP; tx: cisplatin based chemo and XRT; surgery for residual disease
Cysts
- bronchogenic - posterior to carina; tx: resection
* pericardial - at right costophrenic angle; tx: resection
Neurogenic tumors
have pain, neurologic deficit; tx: resection
- 10% have intraspinal involvement that requires simultaneous spinal surgery
- neurolemmoma - most common
- paraganglioma - produce catecholamines
- nerve sheath - assoc with von Recklinghausen’s disease
- can also get neuroblastomas and neurofibromas
mediastinal mass
50% of symptomatic mediastinal masses are malignant
90% of asymptomatic mediastinal masses are benign
Trachea tumors
benign adults papilloma, children hemangioma
malignant squamous cell ca
most common late complication after tracheal surgery
granulation tissue formation
most common early complication after tracheal surgery
laryngeal edema
*tx: reintubate, racemic epinephrine, steroids
Postintubation stenosis
at stoma site with tracheostomy; at cuff with ET tube
- may be able to treat with serial dilation or with laser
- may need resection with end-to-end anastomosis if severe
Tracheoinnominate fistula
trach - needs to be between 1st and 2nd tracheal rings not > 3 ring - risk of TIF
*tx: overinflate balloon to plug hole or stick finger in hole and depress innominate artery; resect innominate and place graft; leave trachea alone; use new trach site
lung abscess
necrotic area; most common assoc with aspiration
most commonly posterior segment of RUL and superior segment of RLL
*tx: abx 95% successful; CT guided drainage if fails
*surgery if this fails or cannot r/o cancer (>6cm, failure to resolve after 6 weeks)
*chest ct can help differentiate empyema from lung abscess
Empyema
- usually 2/2 PNA and subsequent parapneumonic effusion (staph, strep)
- can also be due to esophageal, pulm or mediastinal surgery
- pleuritic chest pain, fever, cough, SOB
- pleural fluid often has WBCs > 500cells/cc, bacteria, +gram stain
- exudative phase (1st week) - tx: chest tube, abx
- fibroproliferative phase (2nd week) - tx: chest tube, abx
- organized phase (3rd week) - tx: likely need decortication; fibrous peel occurs around lung
- may need Eloesser flap (direct opening to external environment) for chronic unresolving empyema
Chylothorax
- fluid mikly white; has increase lymphocytes and TAGs (>110mL/uL); Sudan red stains fat
- fluid resistant to infection
- 50% 2/2 trauma or iatrogenic injury
- 50% 2/2 tumor (lymphoma most common, due to tumor burden in lymphatics)
- injury above T5-6 results in left sided chylothorax
- injury below T5-6 results in right sided chylothorax
- 3-4 weeks of conservative therapy (chest tube, octreotide, low fat diet or TPN)
- if that fails surgery with ligation of thoracic duct on right side low in mediastinum (80% successful) if chylothorax 2/2 trauma or iatrogenic injury
- for malignant causes of chylothorax can perform mechanical or talc pleurodesis
Massive hemoptysis
> 600 cc / 24h
- bleeding is from high pressure bronchial arteries
- most commonly 2/2 infection, mycetoma most common
- death due to asphyxiation
- tx: place bleeding side down if known: rigid bronch to identify site; mainstem intubation to side opposite of bleeding to prevent drowning in blood; to OR for lobectomy or pneumonectomy; bronchial artery embolization if not suitable for surgery
Spontaneous pneumothorax
tall, healthy, thin, young males
- recurrence risk after 1st pneumothorax 20%, after 2nd pneumothorax 60%, after 3rd pneumothorax 80%
- results from rupture of a bleb in apex of upper lobe of lung; can occur in superior segment of lower lobe
- more common right
- tx: chest tube
- surgery for recurrence, large blebs on CT scan, air leak > 7 days, nonreexpansion
- also need surgery for high risk profession (airline pilot, diver, mountain climber) or patient who lives in remote areas
- VATS, apical blebectomy, mechanical pleurodesis
Sequestration
- lung tissue in lung not connected to bronchial tree
- receives blood supply from anomalous systemic arteries –> usually off thoracic aorta (can also come from abdominal aorta through inferior pulmonary ligament)
- venous blood supply is either pulmonary vein or systemic veins
- extrolobar - more common in children; more likely to have systemic venous drainage
- intralobar - more common in adults; more likely to have pulmonary vein drainage
tx: lobectomy
Solitary pulmonary nodule with h/o previous cancer
- sarcoma / melanoma –> nodule more likely mets
- head / neck / breast –> nodule more likely primary lung CA
- GI / GU –> mets or primary
- in case of primary cancer with a resectable lung mets, take out primary 1st, then mets
Tension pneumothorax
most likely to cause arrest after blunt trauma; impaired venous return
Catamenial pneumothorax
occurs in temporal relation to menstruation
*caused by endometrial implants in visceral lung pleura
Residual hemothorax despite 2 good chest tubes
OR for VATs drainage
Broncholiths
usually 2/2 infection
Mediastinitis
usually after cardiac surgery
White out on chest xray
- midline shift toward whiteout - most likely collapse –> need bronch to remove plug
- no shift –> CT scan
- midline shift away from whiteout - most likely effusion –> place chest tube
Bronchiectasis
acquired from infection, tumor, cystic fibrosis
TB
lung apices; get calcifications, caseating granulomas
- Ghon complex –> parenchymal lesion + enlarged hilar nodes
- tx: rifampin, INH, pyrazinamide
Sarcoidosis
has noncaseating granulomas
Effusions
exudative: protein > 3 specific gravity > 1.016 LDH ratio (pleural fluid: serum) >0.6 decreased glucose pH < 7.45 wbc > 1,000
Recurrent pleural effusions
can be treated with mechanical pleurodesis
*talc pleurodesis for malignant pleural effusions
Airway fires
usually assoc with laser
*tx: stop gas flow, remove ET tube, reintubate for 24 hours, bronch
Chest wall tumors
benign osteochondroma
malignant chondrosarcoma
