Respiratory: Pneumothorax Flashcards
Describe the differing types of pneumothorax [4]
Spontaneous:
- Primary: ‘normal lungs’
- Secondary: ‘Pre-existing lung disease
Non-spontaneous:
- Traumatic
- Iatrogenic
What are the most common causes of iatrogenic pneumothorax? [2]
- Pleural aspiration / chest drain insertion for pleural fluid
- Central venous line insertions
State risk factors for primary pneumothorax [5]
Fit, young people
Tall, thin men
Male sex
Smoking cigarettes and cannabis
Fx
Chest trauma
State causes of secondary pneumothorax:
-Obstructive airway disease [2]
- Infections [2]
- Suppurative lung disease [3]
- Interstitital lung disease [4]
- Genetic [3]
- Other
Obstructive airway disease:
- COPD
- Asthma
Lung and pleural malignancies
Infection:
- TB
- Pneumonia
Suppurative lung disease:
- Cystic fibrosis
- Bronchiectasis
- Lung abscess
Interstitial lung disease:
- Sarcoidosis
- IPF
- Hypersensitivty pneumonitis
- Pneumoconiosis (any lung disease caused by the inhalation of organic or nonorganic airborne dust and fibers)
Genetic:
- CF
- Marfans
- Birt-Hogg-Dube syndrome
Despite the fact that primary pneumothorax is thought to occur in healthy lungs, there are thought to be predisposing factors that contribute to this pathology. Explain what these are [1]
Air bulla (bubbles on surface of pleura) that weaken the visceral pleura and burst
Uncertain why this happens - possibly due to inflammation
What is the clinical significance of primary vs secondary pneumothorax? [1]
Secondary has higher mortality
Describe the clinical features of both primary and secondary pneumothorax [6]
They’re the same
- Acute onset
- Pleuritic chest pain
- SOB
- Cough (late sign)
- Dysopnea (more common in secondary spontaneous
- Ipsilateral reduced breath sounds
- Hypoxia (late sign)
State 3 respiratory and 5 cardiac differential diagnosis
Respiratory:
- PE
- Pneumonia
- Acute exacerbation of respiratory disease
CV:
- MI / ACS
- Pericarditis
- AAA or aortic dissection
- Cardiac tamponade
Describe the clinical signs of pneumothorax [3]
What further signs would indicate that the pneumothorax is severe? [4]
Initial:
* Reduced chest expansion on side of pneumothorax
* Hyper resonant percussion
* Quiet breath sounds
Severe:
* Tachycardia
* hypoxia
* tachypnea
* hypotension
What are the key investigations of pneumothorax? [4]
- PA CXR
- ChestCT (if CXR inconclusive)
- ECG
- Bloods
- Point-of-care ultrasound (POCUS) - useful bedside diagnosis
What does this CXR inidacate? [1]
Giant bulla (not a pneumothorax!)
What are you trying to ID on a CXR to determine if have a pneumothorax? [2]
What is the difference between small and large pneumothorax? [2]
CXR findings:
* No peripheral lung markings
* Visceral pleural line
Size: measure at level of hilum the distance between lung margin and cest wall:
- Small : < 2cm
- Large: > 2cm
What do you need to spefically look at on a blood test prior to treating a pneumothorax with a chest drain? [1]
Correct clotting abnormalities (INR ≥1.5 or platelets ≤50 x 10⁹/L) before inserting a chest drain in patients who are not critically unwell
What is the most common finding of an ABG of pneumothorax patient? [1]
respiratory alkalosis is the most common finding
Describe the general management plan for pneumothoraxes [5]
15 L oxygen
Medical:
- Pleural aspiration
- Chest drain
Surgical
- Open thoracotomy
- Video assisted thoracic surgery (VATS)
Describe the mangement plan for a primary pneumothorax if the patient has no shortness of breath and less than a 2cm rim of air on the chest x-ray [2]
- No treatment is required as it will spontaneously resolve
- Follow-up in 2 – 4 weeks is recommended
Describe the mangement plan for a primary pneumothorax if the patient has shortness of breath or more than a 2cm rim of air on the chest x-ray: [2]
Be specific
Aspiration with 16-18G cannula; aspirate < 2.5L followed by reassessment
When aspiration fails twice, a chest drain is required
Describe the mangement plan for a primary pneumothorax if the patient has bilateral pneumothorax or is haemodynamically unstable [1]
Chest drain
Describe the location of chest drain procedure [4]
Chest drains are inserted in the “triangle of safety”. This triangle is formed by the:
- 5th intercostal space (or the inferior nipple line)
- Midaxillary line (or the lateral edge of the latissimus dorsi)
- Anterior axillary line (or the lateral edge of the pectoralis major)
The needle is inserted just ABOVE the rib to avoid the neurovascular bundle that runs just below the rib. Once the chest drain is inserted, obtain a chest x-ray to check the positioning.
What should you do to check positioning of chest drain? [1]
Once the chest drain is inserted, obtain a chest x-ray to check the positioning.
Desribe the mechanism of a chest drain treating pneumothorax
The external end of the drain is placed underwater: creating a seal and one way valve to prevent air from flowing back through the drain into the chest.
Air can exit the chest cavity and bubble through the water
But the water prevents air from re-entering the drain and chest.
During normal respiration, the water in the drain will rise and fall due to changes in pressure in the chest (described as “swinging”).