Pneumothorax Flashcards
Define pneumothorax
Presence of air in the pleural space, disrupts negative intrapleural pressure leading to partial or complete lung collapse.
What are the different aetiological classifications of pneumothorax?
Spontaneous (primary no underlying lung disease, secondary uld)
Traumatic - blunt or penetrating
Iatrogenic - ventilation, central line etc
What is the relevant epidemiology of pneumothorax?
Peak incidence in 20-30yrs
Three times as common in males
Exam stem: young talll thin male sudden onset SOB and pleuritic chest pain.
What are some common causes of a pneumothorax?
Spontaneous
Trauma
Iatrogenic - lung biospy, mechanical ventialtion or central line insertion
Lung pathologies - infection, asthma or COPD
What are some risk factors for pneumothorax?
Tall, lean and male - subpleural blebs
Trauma to the chest
Smoking
Pre-exisiting lung disease: COPD, asthma, CF, lung cancer
Connective tissue disorder: Marfan syndrome, RA
Ventilation
Catamenal pneumothorax - up to 6% of spontaneous in women, relate to endometriosis on thorax
Explain the basic pathological process of a pneumothorax.
- Damage to visceral or parietal pleura
- Air enters pleural space from alveoli or atmosphere
- Disrupts negative pressure in pleural space, equalised with atmospheric - partial or complete lung collapse
- Varies in speed of air accumulation
- Inflammation and repair in response - pleural pain + tachycardia, adhesions form, eventually obliteral intrapleural space preventing recurrence (mostly)
What is meant by a tension pneumothorax?
Medical emergency
Caused by trauma to the chest or spontaneous - results in a one way valve dected that allows air in but not out of the pleural space - rapidly grows with each breath
Can displace/push mediastinal structures to the side (away from pneumothorax)
Results in severe respiratory distress and haemodynamic collapse
What are the symptoms of a pneumothorax?
Acute SOB
Pleuritic chest pain
Central cyanosis
Lightheadedness and near fainting - hypercapnic coma in severe cases.
What are the signs of a pneumothorax?
Tachypnoea
Tachycardia
Hypotensive (tension)
Hypoxic
Reduce breath sounds on affected side
Hyperresonance on percussion
Decreased chest expansion on affected side
Tension - tracheal deviation, JVP distention, hemodynamic instability.
What are the investigations for a pneumothorax?
Bedside - obs, resp, cardio, ECG, echo, POCUS
Bloods - CRP, LFT, U&E, FBC, ABG,
Imaging - erect CXR, CT thorax may be used secondary to assess small or size
What is the gold standard imaging tool for a pneumothorax?
How do you measure the size of a pneumothorax?
An erect CXR
Measure at the level of the hilum, measure the distance between the lung edge (end of lung markings) to the inside of the chest wall.
What are the different patient profiles that receive different treatment for pneumothorax based on BTS guidelines?
Asymptomatic patient - conservative care
Symptomatic and high risk
Symptomatic and low risk: less than 2cm generally conservative, more than 2cm patient priority.
What are the high risk patient characteristics with a pneumothorax?
Haemodynamic compromise (tension pneomothorax)
Significant hypoxia
Bilateral pneumothorax
Underlying lung disease
>50yrs old with sig smoking history
Haemopnuemothorax
How do you determine if intervention is safe for a pneumothorax?
Before needle aspiration/chest drain insertaion must have 2cm laterally or apically on CXR
Any size on CT scan which can be safely accessed with radiological support.
What conservative care is given for a pneumothorax?
For asymptomatic patients with no high risk characteristics
Primary spontaneous - review every 2-4days as outpatient
Secondary spontaneous - monitor as inpatient
If stable follow up as outpatient in 2-4 weeks.
Pneumothorax treatment pathways flow diagram
