Lung Collapse and SVCO

Question 1

What are the causes of lung collapse?

Answer 1

Reabsorption of air and alveolar collapse due to bronchial obstruction (commonest), less commonly non-obstructive atelectasis

Intraluminal
- Mucous plugging from asthma or ABPA
- Foreign body

Endobronchial
- Tumour
- TB

Extraluminal/Extrinsic (compression) - non-obstructive atelectasis
- Lymphadenopathy
- Sarcoidosis
- Lymphomas
- TB
- Aortic aneurysm
- Pneumothorax
- Pleural effusion
- ILD and its causes

Others
Phrenic nerve palsy

Question 2

What are the clinical findings/signs of lung collapse?

Answer 2

1. Functional status: likely breathless, requiring oxygen support
2. Trachea deviation to the side of collapse +/- apex beat deviation to side of collapse
3. Flattened chest wall with diminished chest expansion on affected side
4. Dullness to percussion
5. Diminished breath sound and vocal resonance

Explore on cause of lung collapse
- Cachexia, finger clubbing, tar staining, palpable lymph node - malignancy
- Apical signs, lymphadenopathy - PTB
- Erythema nodosum, maculopapular skin lesion, lupus pernia, lymphadenopathy - sarcoidosis
- Asthma, COPD, bronchiectasis - mucous plugging

Question 3

What is Brock’s syndrome?

Answer 3

Collpase of right middle lobe from enlarged LNs

Question 4

How do you investigate the lung collapse?

Answer 4

1. CXR
2. Bloods - FBC, biochemical, ABG
3. Sputum AFB smear and culture
4. Sputum cytology
5. Bronchoscopy and biopsy
6. Staging CT TAP with adrenal cuts
7. Bone scan
8. Physiological staging with lung function test
   - FEV1 > 1.5, transfer factor > 50%

Question 5

What is SVCO? (Superior vena cava obstruction)
Describe the drainage of veins to SVC

Answer 5

Tumour obstructing the SVC causing fixed engorgement of neck veins, loss of classical JVP waveform
Causes: lung carcinoma (small cell), lymphoma, mediastinal mass (mediastinal goitre, massive thymoma)

SVC drains blood from head, neck, upper limbs and upper thorax (above the nipples)

Question 6

What are the causes of SVCO?
(M: 6TV)

Answer 6

1. Tumour (bronchogenic carcinoma, lymphoma, RA myxoma)
2. Tuberculosis -> lymphadenopathy
3. Thyroid (goitre)
4. Teratoma
5. Thymoma
6. Thrombosis of central vein (thrombophilia, central lines)
7. Vasculitis

Question 7

What are the symptoms of SVCO?

Answer 7

1. Dyspnoea
2. Headache
3. Nasal stuffiness
4. Head, facial and arm swelling
5. Visual disturbance
6. Dysphagia
7. Dizziness

Symptoms worsens on bending forward, lying down or coughing

Question 8

What are the examination findings/signs of SVCO?

Answer 8

1. Plethoric facies
2. Facial and UL oedema
3. Conjunctival suffusion
4. Multiple venous angiomata on undersurface of tongue
5. Fixed engorgement of neck veins, non-pulsatile
6. Stidor
7. Upper chest telangiectasia and dilated superficial veins of UL, neck, chest wall

Identifying causes:
- Radiation marks
- Cachexia, tar staining - malignancy
- Recent or current central venous access - line thrombosis

Question 9

How do you manage SVCO?

Answer 9

Medical emergency

1. Head elevation
2. IV furosemide
3. Corticoteroids to reduce cerebral or laryngeal oedema
4. Expandable metal stenting while awaiting histology confirmation
5. Thrombolysis or anticoagulation (central venous thrombosis)
6. Mediastinal irradiation within 24 hours (NSCLC or lymphoma)
7. Chemotherapy (SCLC)

Question 10

What is the prognosis of SVCO?

Answer 10

Benign cause: no effect on prognosis

Malignant cause: survival correlates with histology