A collapsed lung, medically termed a pneumothorax, is a condition where air collects in the chest cavity outside of the lung itself. This buildup of air creates pressure that pushes on the lung, causing it to partially or fully deflate. The lung is no longer able to expand properly when a person inhales, which compromises the body’s ability to take in oxygen. Recognizing the signs is crucial because the condition can rapidly become life-threatening. This article provides a clear understanding of the mechanism, the distinct warning signs, and the immediate steps required to seek medical help.
What is a Collapsed Lung?
The mechanism of a pneumothorax involves the disruption of a delicate pressure balance within the chest. The lungs are surrounded by a thin, two-layered membrane called the pleura, creating the pleural cavity. Normally, this cavity maintains a negative pressure, which acts like a vacuum seal, keeping the lung inflated against the chest wall.
A pneumothorax occurs when air enters this pleural space, equalizing the pressure and breaking the seal that holds the lung open. This air accumulation forces the lung tissue to recoil inward, leading to a collapse. The air source can be external, such as from a penetrating chest injury, or internal, where air leaks from the lung’s own airways.
Pneumothoraces are categorized by their origin. Traumatic pneumothorax results from an injury to the chest wall or lung tissue. Spontaneous pneumothorax occurs without any apparent injury, often due to the rupture of small, air-filled sacs on the lung surface.
Distinct Symptoms of Pneumothorax
The sudden onset of sharp, one-sided chest pain is the primary sign of a pneumothorax. This pain is described as “pleuritic,” meaning deep breathing, coughing, or sneezing intensifies it. The pain typically signals the moment air begins to accumulate and pressure builds against the lung.
Acute shortness of breath (dyspnea) accompanies the chest pain due to the lung’s inability to fully expand. This breathlessness can range from mild difficulty catching one’s breath to severe respiratory distress, depending on the volume of air trapped in the pleural space. Patients may also experience a sensation of tightness or pressure across the chest.
The body’s response often includes an increased heart rate (tachycardia) and rapid breathing. In more severe cases, a lack of oxygen can cause the skin, lips, or nails to develop a bluish tint (cyanosis). If trapped air creates a one-way valve effect, it can lead to a tension pneumothorax, a rapidly worsening condition that causes low blood pressure and shock.
Primary Causes and Risk Factors
Pneumothorax origins are divided into three main groups: traumatic, iatrogenic, and spontaneous. Traumatic causes involve blunt force injuries, such as those sustained in a car accident, or penetrating wounds to the chest. A broken rib that punctures the lung tissue is a common mechanism in this category.
Iatrogenic pneumothorax is a type of collapse caused by medical procedures. This can happen during necessary interventions such as a lung biopsy, the insertion of a central line, or the use of positive pressure mechanical ventilation. These procedures carry a small risk of disrupting the integrity of the lung or chest wall.
Spontaneous pneumothorax occurs without external trauma and is split into primary (PSP) and secondary (SSP) types. PSP often occurs in otherwise healthy individuals, commonly tall, thin men between the ages of 20 and 40. The cause is the rupture of small, air-filled blisters called blebs on the surface of the lung.
Smoking is the most significant risk factor for PSP. SSP is associated with underlying lung diseases that weaken the lung tissue, such as Chronic Obstructive Pulmonary Disease (COPD), emphysema, cystic fibrosis, and certain connective tissue disorders.
Seeking Emergency Medical Care and Diagnosis
Any individual who experiences the sudden onset of sharp chest pain accompanied by significant shortness of breath must seek emergency medical care immediately. A pneumothorax can progress quickly, making immediate evaluation in an emergency department necessary. If symptoms are severe or rapidly worsening, calling emergency services is the correct course of action.
Medical professionals will first perform a physical examination, listening for decreased or absent breath sounds on the affected side of the chest. The definitive diagnosis relies on imaging studies. A chest X-ray is the most common and rapid tool used to confirm the presence of air in the pleural space.
The X-ray will show the visible line of the visceral pleura, with a lack of lung markings peripheral to this line, which confirms the collapse. If the initial X-ray is inconclusive, a computed tomography (CT) scan may be used. Treatment is determined by the size of the collapse and the patient’s stability, ranging from observation for small pneumothoraces to the insertion of a needle or chest tube to remove the trapped air.