Thoracic

High Yield Anatomy

How many lobes on the right vs left?
3 vs 2 anatomic lobes
What is a good way to remember the lymph node stations?
Single digits are mediastinal vs double digits are hilar
What is the full course of the thoracic duct?
Cisterna chyli (L2) → crosses at T5 from right to left → empties into junction of L internal jugular and subclavian veins
What is the final destination of the azygous?
Superior vena cava Where do you find the duck (thoracic duct)? Between the two goose - azyGOOSE vein and esophaGOOSE
Where do the nerves run in relation to the hilum of the lung?
Phrenic nerve is anterior
oVagus nerve runs posterior Think alphabetical order: A (anterior) before P (posterior) P (phrenic) → anterior comes before V (vagus) → posterior
What are the anatomic boundaries of the mediastinum?
Sternum anteriorly, vertebrae posteriorly, pleurae laterally, thoracic inlet superiorly, diaphragm inferiorly
What are the types of pneumocytes and their function?
Type 1 = gas exchange
Type 2 = makes surfactant (phosphatidylcholine is the primary component)
What are the pores of Kahn?
Pores in alveoli that enable direct air exchange

Space of Disse is the hepatic analog: hepatocytes interact directly with the sinusoids Functional Definitions

Pulmonary Function Tests
What is the pre-op workup of a patient you are considering for lobectomy?
Predicted forced expiratory volume FEV1 > 0 .8 (80%)
If close → V/Q scan will show contribution of the diseased lung
FEV1 is the best predictor of post op complications . What else is predictive of increased perioperative risk?
Diffusion capacity of the lung for CO2 or DLCO < 10 mL/min/mm (40% predicted)
What is Light’s criteria?
Characterize pleural fluid as exudate vs transudate
Pleural:serum protein ratio > 0 .5
Pleural:serum LDH ratio > 0 .6
Pleural LDH > 2/3 of normal serum LDH Pleural disease
Pleural effusion and Empyema
What causes these?
Increased permeability of the pleura and capillaries (sepsis, malignancy, pancreatitis)
Increased hydrostatic pressure (CHF, CKD)
Hypoalbuminemia (cirrhosis, nephrotic syndrome, malnutrition)
What type of imaging should you get and what would you see?
CXR = blunting of costophrenic angle, visible effusion if > 300 mL, fluid in fissures
US = fluid in the pleural space with loss of inspiratory sliding
CT chest = simple effusion will be homogeneous, most are posterior and inferior vs an empyema would be a loculated, heterogeneous collection
Treatment?
Pleural effusion → conservative management, treat underlying cause, unless symptomatic then drain
Empyema → decortication
How do you manage a retained hemothorax?
Chest tube → VATS or thoracotomy for washout
Chylothorax
How do you diagnose it?
Milky white fluid
110 mg/dL triglycerides with lymphocyte predominance
Sudan red stains fat and will be positive
What are the most common etiologies?
50% are due to malignancy (lymphoma)
What causes the other 50%?
Trauma or iatrogenic
When do symptoms begin after iatrogenic injury?
After initiation of oral intake
What is the management?
First-line is conservative management with low fat, medium-chain fatty acid diet (no long-chain FAs) or bowel rest with TPN if high-volume or persistent leak on the oral diet, chest tube if necessary, +/- octreotide
If fails or due to traumatic injury → ligation of thoracic duct in low right mediastinum vs talc pleurodesis and possible chemoradiation for malignancy
18-year-old basketball player, occasionally uses marijuana, suddenly felt chest pain with inspiration while watching TV .

What does he likely have?

Spontaneous pneumothorax due to apical subpleural blebs
What is the difference between primary and secondary PTX?
Secondary is due to an underlying medical condition . Examples?
COPD most common, asthma, CF, infection, malignancy, connective tissue disease, congenital cysts, etc .
ED confirmed PTX on CXR and intern goes down to see. At this point he looks anxious, working a bit to breathe, HR 120, RR 30, BP 90/50, with a prominent neck vein . What does he have?
Tension pneumothorax - if the intern isn’t too far into surgical residency, he/she probably took a stethoscope and heard an absence of breath sounds on the affected side
What is the first step in managing this?
Needle decompression
How would you do that?
Insert a needle, angiocaths are readily available, into the second intercostal space at a 90-degree angle to the chest, just over the third rib .
In reality, we would place a chest tube which would be just as quick
Back to non-tension PTX . How do you manage these?
For clinically stable with small PTX → observe
For clinically stable with large (> 3 cm) → pigtail catheter or chest tube
For unstable and large → chest tube
When do you operate?
Persistent air leak (> 4 days) → VATS with pleurodesis
After second recurrence of spontaneous/primary → blebectomy
High-risk profession after first occurrence (scuba diver, pilot)

Spontaneous pneumothorax in the OR, don’t see blebs. What do you do? Apical wedge resection

How do you perform a pleurodesis?
Can do mechanical with scratch pad, bovie, etc .
Chemical = doxycycline, bleomycin, talc
Pleurectomy
Indwelling intrapleural catheter
Goal is to abut the visceral and parietal pleura by causing an inflammatory reaction that scars them together Mediastinal disease
60-year-old alcoholic went on a binge and had massive, forceful emesis . Comes to the ED with chest pain, fever, tachycardia . CXR unremarkable . Next step?
Worried about esophageal perforation so gastrografin swallow; also need to see extent of mediastinitis → CT neck/chest with PO and IV contrast
Acute mediastinitis usually due to acute perforation of esophagus or trachea and can lead to descending necrotizing infection → sepsis
Can also be caused by oropharyngeal infections (Ludwig angina)
Chronic mediastinitis usually manifests as fibrosis
How do you manage acute mediastinal infection?
Source control, antibiotics → sternal debridement if postop sternotomy is the etiology, cervical drain if cervical infection, VATS to drain mediastinum into pleural space if lower mediastinal infection
Mediastinal tumors
Most common cause of mediastinal adenopathy?
Lymphoma
Most common overall type of mediastinal tumor in adults and children?
Neurogenic (posterior mediastinum)
Most common site of mediastinal tumor?
Anterior = terrible Ts → thymoma, teratoma, thyroid (ectopic), (terrible) lymphoma
What else do you need to check in a male who presents with a mediastinal mass?
Scrotum (germ cell tumor)
Most common germ cell tumor?
Teratoma
And where is that located?
Anterior mediastinum
Thymomas and myasthenia gravis
50% of thymomas are malignant
50% are symptomatic
50% have myasthenia
10% of patients with myasthenia have a thymoma
80% of myasthenia patients will improve with thymectomy
Superior vena cava syndrome
Causes?
Malignancy most common (60%) → small cell lung cancer most common, then lymphoma
Nonmalignant = fibrosing mediastinits, substernal thyroid goiter, sarcoid, etc ., secondary to indwelling intravascular devices
How do they present?
Venous obstructive symptoms with dilation of head and neck veins and facial, neck, or arm swelling; can get laryngeal and tracheobronchial compression
Fullness in the head when bending over
Can be associated with Horner syndrome if due to a pancoast tumor = ptosis, miosis, anhidrosis
Diagnosis: CXR, CT with contrast, +/- venography
Treatment = position patient to reduce edema, steroids, +/- anticoagulation, emergent radiation if very symptomatic, treat underlying cause Lung Masses
What are the screening recommendations?
Annual low-dose CT for 3 years in 55-80-year-old current or former smokers with > 30 pack-year history or quit within the past 15 years
Is lung cancer still the #1 cause of cancer-related death in the US?
Yes
Strongest prognostic indicator?
Nodal involvement
Most common site of metastases?
Brain (also goes to supraclavicular nodes, contralateral lung, bone, liver, adrenal)
Solitary pulmonary nodule
What is the workup?
Must ask 2 questions:
Is it a benign calcification or stable for 2 years? → no further work up
Is the surgical risk acceptable? If no, consider biopsy for diagnosis and radiation for palliation if necessary
If growing over 2 years but acceptable surgical risk, consider clinical probability of cancer
Low → serial CT at 3, 6, 12, 24 months
Intermediate → PET/CT, transthoracic or bronchoscopic biopsy
High → VATS biopsy with frozen section and then lobectomy if malignant
Lung cancer
What is the most common type of lung cancer?
Non-small cell (80%)
Squamous and small cell are more central versus adenocarcinoma is peripheral
There are some paraneoplastic syndromes associated with lung cancer, what are they?
Squamous cell = PTH-related peptide causing hypercalcemia
Small cell = ACTH (most common paraneoplastic syndrome) and ADH secretion
When do you perform mediastinoscopy?
Centrally located tumors or suspicious adenopathy
Positive mediastinal nodes = unresectable tumor Mediastinal nodes are single digits.
Which nodes are not assessed?
Aortopulmonary
Need to perform Chamberlain procedure = anterior thoracotomy or parasternal mediastinotomy through L 2nd rib cartilage
What is the TNM staging?
T stages
T1 < 3 cm
T2 3-5 cm
T3 5-7 or invading chest wall or pericardium
T4 > 7 cm or invading mediastinum, etc .
N stages
N3 = supraclavicular or cervical LN
Metastases
Hematogenous spread to brain, adrenals, contralateral lung, bone
MRI brain for neurologic complaints, Stage III/IV or small cell and Pancoast tumors
What is the treatment?
Stage I and II = resection or definitive radiation if not a surgical candidate
Locally advanced Stage III can be resected after neoadjuvant chemoXRT
Stage IIIb with T4 tumor or N3 lymph nodes require chemoradiation
Stage IV usually palliative resection or radiation
When can you do VATS versus open resection?
Tumor < 5 cm, peripheral, no regional lymphadenopathy or local invasion
What are the surveillance recommendations?
Stage I/II: H&P with CT chest every 6 months for 3 years → annual H&P with noncontrast CT chest
Stage III/IV: H&P with CT chest every 3-6 months for 3 years → H&P with CT chest every 6 months → annual Trauma
What volume of blood from a chest tube indicates need for OR?
1500 mL initially or 200-300 mL/h for 2-4 hours
What are the indications for a resuscitative thoracotomy?
Penetrating injury with < 15 min CPR
Penetrating extrathoracic injury with exsanguination and < 5 minutes CPR
Blunt trauma losing vital signs en route or witnessed in ED with < 10 min CPR
What are the steps in a resuscitative thoracotomy?
Nasogastric or orogastric tube to help identify esophagus
Double lumen intubation to deflate lung on side of injury
Anterolateral incision to enter chest → rib spreader → pericardiotomy and control cardiac injury, cross clamp aorta, cardiac massage Quick Hits
Massive bleeding in patient with tracheostomy . What is it? Management?
Tracheoinnominate fistula
Temporizing measures: inflate cuff, anterior pressure of finger through trach opening
Place trach hole and rush to OR for median sternotomy and ligation and resection of innominate artery

Do not pick reconstruction of the artery, it will blow out.

How do you prevent this fistula?
Place trach between 2nd and 3rd tracheal ring
Do pericardial cysts have to be resected?
No if asymptomatic, find them at the right costobronchial angle
Do bronchiogenic cysts have to be resected?
Yes, find them posterior to carina
Most common benign/malignant tumor in adults?
Benign: Hamartoma
Popcorn lesion +/- calcifications
No treatment → repeat CT in 6 months to confirm diagnosis
Malignant: squamous cell carcinoma
Most common tumors in children?
Benign: Hemangioma
Malignant: Carcinoid
What type of lung cancer mimics pneumonia?
Bronchoalveolar cancer and it grows along the alveolar walls, usually multifocal