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What is a pneumothorax?

A condition in which air leaks into the pleural space, causing the lung to partially or completely collapse.

Where is the pleural space located?

Between the lung and the chest wall.

What normally keeps the lungs inflated against the chest wall?

A delicate pressure system within the pleural space.

What happens when air enters the pleural space?

The normal pressure system is disrupted, causing the lung to partially or completely collapse.

How does a pneumothorax affect breathing?

Lung collapse compromises the patient's ability to breathe effectively.

What are the two broad categories of pneumothorax?

Spontaneous and acquired.

What is a spontaneous pneumothorax?

A pneumothorax that occurs without external trauma or a medical procedure.

What is an acquired pneumothorax?

A pneumothorax that develops because of external trauma or a medical procedure.

What are the two types of spontaneous pneumothorax?

Primary spontaneous pneumothorax (PSP) and secondary spontaneous pneumothorax (SSP).

What is a primary spontaneous pneumothorax (PSP)?

A spontaneous pneumothorax occurring in an individual with no known lung disease.

What patient profile is classically associated with primary spontaneous pneumothorax?

A tall, thin, young male aged 15–34.

What is a major lifestyle risk factor for primary spontaneous pneumothorax?

Smoking.

How much can smoking increase the risk of primary spontaneous pneumothorax according to the notes?

Up to 22 times higher.

What causes a primary spontaneous pneumothorax?

Rupture of asymptomatic, air-filled sacs called blebs on the lung surface.

What are blebs?

Small, air-filled sacs on the surface of the lung that can rupture and cause a pneumothorax.

When can blebs rupture to cause a primary spontaneous pneumothorax?

Often while the person is at rest.

How may a patient with a primary spontaneous pneumothorax appear in the emergency room?

The patient may appear relatively well despite having a collapsed lung.

Why can a primary spontaneous pneumothorax be underestimated?

The patient may appear relatively stable despite having a collapsed lung.

What is a secondary spontaneous pneumothorax (SSP)?

A spontaneous pneumothorax occurring in a patient with pre-existing lung disease.

What is an important risk factor for secondary spontaneous pneumothorax?

COPD.

What other respiratory disease is a risk factor for secondary spontaneous pneumothorax?

Asthma.

What infection is a risk factor for secondary spontaneous pneumothorax?

Pneumonia.

What other infectious disease is a risk factor for secondary spontaneous pneumothorax?

Tuberculosis.

What genetic lung disease is a risk factor for secondary spontaneous pneumothorax?

Cystic fibrosis.

Why are symptoms often more severe with a secondary spontaneous pneumothorax?

The patient's lung reserve is already compromised by pre-existing lung disease.

Why can a secondary spontaneous pneumothorax be difficult to recognize?

Baseline dyspnea from the underlying lung disease can mask the additional respiratory compromise caused by the pneumothorax.

Why is early recognition especially important with a secondary spontaneous pneumothorax?

The patient's respiratory reserve is already compromised.

What are the two major categories of acquired pneumothorax?

Traumatic and iatrogenic pneumothorax.

What is a traumatic pneumothorax?

A pneumothorax caused by physical trauma.

What are two major types of traumatic injury that can cause pneumothorax?

Penetrating trauma and blunt trauma.

What are examples of penetrating trauma that can cause pneumothorax?

Gunshot wounds and stab wounds.

What are examples of blunt trauma that can cause pneumothorax?

Motor vehicle accidents, falls, and CPR-related trauma.

What is an open pneumothorax?

A pneumothorax involving a hole in the chest wall that allows communication with the outside environment.

What is another name for an open pneumothorax?

A sucking chest wound.

What sound may be heard with an open pneumothorax?

A distinctive sucking sound during breathing efforts.

What is a closed traumatic pneumothorax?

A pneumothorax in which the pleural space is disrupted by chest trauma without an external opening in the chest wall.

What is an important CPR consideration from the notes?

Breaking ribs is not necessary for effective CPR, and ribs should be avoided from being broken whenever possible.

What is an iatrogenic pneumothorax?

A pneumothorax caused by a medical procedure.

What procedure involving vascular access can cause an iatrogenic pneumothorax?

Central-line insertion.

Which central-line location has a particularly important pneumothorax risk?

Subclavian vein insertion.

Why can subclavian central-line insertion cause a pneumothorax?

The subclavian vein is located near the apices of the lungs.

How can mechanical ventilation cause an iatrogenic pneumothorax?

Excessive positive pressure can rupture alveoli.

What other procedures can cause an iatrogenic pneumothorax?

Lung biopsy and chest surgery.

What is the mechanism of a ventilator-associated pneumothorax?

Excessive pressure can rupture alveoli, allowing air to enter the pleural space.

What is the classic subjective chest-pain symptom of pneumothorax?

Sudden-onset sharp, stabbing, pleuritic chest pain.

What makes pneumothorax-related chest pain worse?

Breathing.

What does pleuritic chest pain mean in this context?

Chest pain that worsens with breathing because the pleural surfaces are irritated.

What respiratory symptom is commonly reported with pneumothorax?

Shortness of breath (dyspnea).

What position may a patient with pneumothorax have difficulty tolerating?

Lying flat.

What unusual sound may a patient report with an open chest wound?

A sucking sound while breathing.

What is tachypnea?

Rapid breathing.

What type of breathing may occur with pneumothorax?

Rapid and shallow breathing.

Why does a patient with pneumothorax breathe rapidly?

Lung collapse impairs gas exchange, causing the body to compensate by increasing respiratory rate.

Why may breathing become shallow with pneumothorax?

The patient limits the depth of breathing to reduce pleuritic pain.

What are accessory muscles?

Muscles of the neck, shoulders, and abdomen recruited to assist breathing.

Why does a patient with pneumothorax use accessory muscles?

Normal respiratory muscles cannot adequately expand the functional lung tissue, so additional muscles are recruited.

What happens to chest-wall movement with pneumothorax?

Chest-wall movement becomes asymmetric.

Which side of the chest has decreased expansion with pneumothorax?

The affected side.

Why is chest expansion asymmetric with pneumothorax?

The collapsed lung cannot follow normal chest-wall movement.

What happens to breath sounds on the affected side?

They become diminished or absent.

Why are breath sounds diminished or absent over the affected lung?

Air in the pleural space acts as a barrier to sound transmission.

Can cough occur with pneumothorax?

Yes.

What is subcutaneous emphysema?

Air trapped in the tissues beneath the skin.

What does subcutaneous emphysema feel like?

A “rice Krispies” or crackling/crunching sensation under the skin.

What cardiovascular signs may occur with larger pneumothoraxes?

Tachycardia, hypotension, and jugular venous distension.

What happens to heart rate with a larger pneumothorax?

Tachycardia may occur.

What blood-pressure change can occur with a larger pneumothorax?

Hypotension.

What happens to the jugular veins with a larger pneumothorax?

Jugular venous distension may occur.

What is a tension pneumothorax?

A life-threatening pneumothorax in which air continuously enters the pleural space but cannot escape.

Why is a tension pneumothorax an emergency?

Increasing pressure rapidly compromises the lung, heart, and great vessels and can cause cardiovascular collapse and death.

What is the mechanism responsible for tension pneumothorax?

A one-way valve effect in which air enters the pleural space but cannot escape.

What happens to pleural pressure during a tension pneumothorax?

Pressure continuously increases as trapped air accumulates.

What happens to the affected lung during a tension pneumothorax?

The lung becomes completely compressed/collapsed.

What happens to the mediastinum during a tension pneumothorax?

It shifts toward the unaffected side.

What does mediastinal shift do to the heart and great vessels?

It compresses them.

How does mediastinal compression affect venous return?

It dramatically decreases venous return to the heart.

How does decreased venous return affect cardiac output?

Cardiac output decreases.

What type of shock can result from tension pneumothorax?

Obstructive shock.

What can untreated tension pneumothorax progress to?

Cardiovascular collapse and death.

Why does a tension pneumothorax become primarily a cardiovascular emergency?

Increasing pleural pressure compresses major veins and reduces venous return and cardiac output.

What is a closed tension pneumothorax?

A tension pneumothorax in which trapped air accumulates without an external chest-wall opening.

What is a major cause of closed tension pneumothorax?

Mechanical ventilation with positive pressure.

How can mechanical ventilation create a closed tension pneumothorax?

Positive pressure can rupture alveoli and allow air to enter the pleural space.

What happens during inspiration in a ventilator-associated closed tension pneumothorax?

Air enters the chest through the alveolar rupture.

What happens during exhalation in a ventilator-associated closed tension pneumothorax?

The rupture seals, preventing air from escaping.

Why does the tension pneumothorax worsen with each ventilator breath?

Each positive-pressure breath forces more air into the chest cavity while the air cannot escape.

What is an open tension pneumothorax?

A tension pneumothorax caused by an opening in the chest wall.

What happens during inspiration with an open tension pneumothorax?

Negative pressure pulls air into the pleural space through the chest-wall opening.

What happens during exhalation with an open tension pneumothorax?

The opening seals and traps the air inside.

Why does an open tension pneumothorax worsen with each breath?

More air enters the pleural space during inspiration but cannot escape during exhalation.

Why does pneumothorax cause sharp pleuritic pain?

Air irritates the pleural surfaces, which contain many pain fibers.

Why are breath sounds diminished or absent with pneumothorax?

Air in the pleural space blocks normal sound transmission.

Why does pneumothorax cause shortness of breath?

The collapsed lung impairs gas exchange.

Why does pneumothorax cause tachypnea?

The body increases respiratory rate to compensate for impaired gas exchange.

Why does pneumothorax cause shallow breathing?

Patients limit breathing depth to reduce pleuritic pain.

Why does pneumothorax cause accessory-muscle use?

Additional muscles are recruited because normal muscles cannot adequately expand functional lung tissue.

Why does pneumothorax cause asymmetric chest movement?

The collapsed lung cannot expand normally with the chest wall.

Why does pneumothorax cause tachycardia?

The heart compensates for reduced oxygen delivery and/or responds to pain.

When does cyanosis occur according to the notes?

When oxygen saturation drops below 85%.

What causes cyanosis in a severe pneumothorax?

Increased deoxygenated hemoglobin caused by inadequate oxygenation.