Mechanical ventilation helps a person breathe by pushing air into the lungs. Because this creates pressure, it can sometimes cause air to leak from the lung into the space between the lung and chest wall. This is called a pneumothorax, or collapsed lung. A small leak may be manageable, but it can sometimes worsen quickly during ventilation and needs urgent treatment, especially if it affects blood flow.
How Are Mechanical Ventilation and Pneumothorax Connected?
Mechanical ventilation is a form of breathing support used when a person cannot breathe adequately on their own. A ventilator delivers air under positive pressure, either through a breathing tube placed in the airway or through a face mask. This support can maintain oxygen levels and remove carbon dioxide, but the pressure involved can also injure vulnerable lung tissue in some circumstances.
According to the Cleveland Clinic, pressure from a ventilator can damage the lungs and, in some cases, contribute to a pneumothorax. The condition develops when air escapes from the lung into the pleural space, the normally very narrow space between the lung and chest wall. The collected air puts pressure on the lung, preventing it from expanding normally.
When a pneumothorax develops during mechanical ventilation, it may be described as a ventilator-associated or ventilation-related pneumothorax. It can occur during invasive ventilation or, in certain circumstances, with noninvasive positive-pressure support. The underlying lung illness, previous lung damage, and the pressures needed to support breathing all influence the risk.
What Causes a Pneumothorax During Ventilation?
Ventilation-related pneumothorax is commonly associated with barotrauma, which means injury caused by pressure. Air sacs in the lungs can become overstretched or damaged, allowing air to escape into surrounding tissues or the pleural space. This risk is particularly important when the lungs are already injured or stiff and require substantial pressure to move air.
The Merck Manual Professional Edition identifies pneumothorax as a complication of mechanical ventilation, particularly when higher ventilation pressures are required.
Factors that may increase concern include:
- High airway pressures: Greater pressure may increase stress on vulnerable lung tissue.
- Existing lung injury: Conditions such as acute respiratory distress syndrome (ARDS) can make the lungs more vulnerable to pressure-related damage.
- Underlying lung disease: Diseases that cause damaged or abnormal air spaces, including emphysema, may contribute to the risk of an air leak.
- Other chest injuries or procedures: Trauma or certain medical procedures can cause a pneumothorax in a person who also requires ventilation.
A pneumothorax does not automatically mean that a ventilator has been set incorrectly. It may occur despite appropriate respiratory support, particularly when the lungs are seriously ill. Clinicians balance the need to provide enough ventilation with the need to limit pressure-related injury.
Why Is Tension Pneumothorax Especially Dangerous?
The main concern during positive-pressure ventilation is that air can continue to accumulate in the pleural space. If air enters but cannot escape, pressure inside the chest rises. This is called a tension pneumothorax.
As pressure increases, the affected lung becomes compressed. The pressure can also interfere with blood returning to the heart, reducing the amount of blood the heart can pump. Blood pressure may fall, and the body's organs may receive insufficient blood and oxygen. In a person receiving mechanical ventilation, this process can progress rapidly.
The Merck Manual Professional Edition describes tension pneumothorax as a life-threatening emergency that requires immediate treatment. When clinical findings strongly suggest this condition, treatment should not be delayed while waiting for imaging.
What Signs May Occur During Mechanical Ventilation?
Signs of pneumothorax depend on how much air has accumulated, the person's underlying lung condition, and whether the air is affecting blood circulation. Someone who is awake and able to communicate may experience symptoms such as:
- Sudden or worsening shortness of breath.
- Sharp chest pain, sometimes worse with breathing.
- A rapid heartbeat.
- Increasing difficulty breathing or unusual chest discomfort.
- Bluish or gray discoloration of the lips or skin when oxygen levels are low.
In an intensive care unit, a person receiving invasive ventilation may be unable to describe symptoms, particularly if they are sedated. Healthcare professionals therefore also look for changes in monitored measurements and examination findings. These may include a sudden drop in oxygen levels, a rise in airway pressure, reduced breath sounds on one side of the chest, a rapid heart rate, or an unexpected fall in blood pressure.
These changes can occur with other complications of critical illness and ventilation as well. Their timing, combination, and progression help the clinical team decide which causes need urgent investigation.
How Is Pneumothorax Diagnosed in a Ventilated Patient?
Diagnosis usually begins with a prompt assessment of breathing, oxygen levels, circulation, ventilator readings, and chest examination. Clinicians consider whether the changes developed suddenly and whether there are signs of an air leak or impaired blood flow. A sudden deterioration during ventilation requires rapid assessment because some causes can be life-threatening.
The Cleveland Clinic's pneumothorax guidance describes chest X-rays, computed tomography (CT) scans, and lung ultrasound as imaging methods used to identify air around the lung. In critically ill patients, a portable chest X-ray or bedside ultrasound may help confirm the diagnosis without moving the person away from intensive care.
However, imaging is not always the first step in an emergency. When tension pneumothorax is strongly suspected in an unstable patient, the medical team may need to relieve the pressure immediately rather than wait for an X-ray. This decision is made by trained healthcare professionals using the patient's condition and examination findings.
How Is Pneumothorax Treated During Mechanical Ventilation?
Treatment depends on the patient's stability, the amount of air around the lung, the extent of any ongoing air leak, and whether positive-pressure ventilation must continue. The immediate priorities are to protect breathing and circulation, release trapped air when necessary, and address the cause of the leak.
Emergency treatment for tension pneumothorax
If tension pneumothorax is suspected, clinicians perform urgent decompression to release pressure from the chest. This may involve a needle or another emergency technique, followed by placement of a chest drain. The procedure allows air to escape and helps the lung re-expand. It is an emergency intervention performed by trained medical professionals, not a procedure for patients or family members to attempt.
Chest drain placement
A chest drain, also called a chest tube, is inserted through the chest wall into the pleural space. It is connected to a drainage system that allows air to leave the space around the lung. Chest drainage is often needed when a pneumothorax occurs during ongoing positive-pressure ventilation because pressure from the ventilator may worsen the air leak.
Not every pneumothorax requires the same treatment. In selected stable cases, close observation may be appropriate. However, a person receiving mechanical ventilation generally needs careful assessment because even a small air leak can become more significant. The clinical team decides whether drainage is necessary based on the circumstances rather than using one approach for every patient.
Adjusting ventilator support
The care team may modify ventilator settings to reduce pressure-related stress on the lungs while maintaining adequate oxygen delivery and carbon dioxide removal. The specific changes depend on the underlying illness, lung mechanics, blood gas results, and the patient's response to treatment. Ventilator settings should never be changed by patients or caregivers without the treating team's direction.
Following treatment, clinicians monitor oxygen levels, heart rate, blood pressure, airway pressures, and chest drain function when one is present. Repeat imaging may be used to check whether the lung has re-expanded and whether the air collection is resolving. Persistent air leakage or failure of the lung to re-expand may require further assessment and, in selected cases, surgical treatment.
Can Pneumothorax Be Prevented During Mechanical Ventilation?
The risk can often be reduced, although it cannot be eliminated completely. Clinicians select ventilator settings according to the patient's condition and aim to avoid excessive pressure or lung overdistension while providing enough support for effective breathing. Lung-protective ventilation strategies may be particularly important when the lungs are already injured.
Continuous monitoring also helps the clinical team recognize deterioration promptly. Changes in airway pressure, oxygen requirements, vital signs, or chest examination findings may lead to a rapid review of the ventilator and the patient's lungs. Treating the underlying lung condition and responding early to warning signs are important parts of care.
When someone is already receiving ventilation, a sudden change in breathing, oxygen levels, or blood pressure needs immediate attention from the treating team. For a person outside the hospital who develops sudden chest pain or difficulty breathing, emergency medical assessment is appropriate. Do not stop or adjust prescribed breathing support on your own while seeking help.
What Is Different About Pneumothorax in Newborns?
Newborns, especially premature infants and babies with stiff or injured lungs, have specific risks related to respiratory support. Pneumothorax may develop during mechanical ventilation or continuous positive airway pressure (CPAP), which supplies pressurized air through a mask or nasal interface. Falling oxygen levels, increased breathing effort, or changes in circulation may be important warning signs in this age group.
The Merck Manual's guidance on pneumothorax in newborns explains that some small air collections can be monitored, while breathing difficulty or impaired circulation may require rapid removal of air using a needle or chest drain. Diagnosis and treatment are adapted to the infant's gestational age, lung condition, breathing support, and clinical stability, so neonatal intensive care teams use age-specific assessments and decisions.
For adults and children of any age, the key consideration is whether air around the lung is interfering with breathing or circulation and whether positive-pressure support could make the problem worse. Prompt recognition and an appropriate treatment plan help the clinical team manage this potentially serious complication while continuing to address the illness that required ventilation.