What is Bullous Emphysema?
A bulla is a space larger than 1 cm inside the lung, filled with air due to damage from emphysema. Emphysema limits airflow and causes a permanent enlargement of the air spaces within the lung beyond the smallest air passages known as terminal bronchioles. Around 80% of people with bullae also have pulmonary emphysema. This condition is often called bullous emphysema. It’s a part of a larger condition known as chronic obstructive pulmonary disease (COPD), which is an illness that blocks the airway and is associated with high death rates.
In bullous emphysema, the bullae occur alongside extensive lung damage due to COPD. This condition puts a considerable financial burden on healthcare systems because patients often need frequent medical visits and hospital stays due to worsening symptoms.
What Causes Bullous Emphysema?
The two main reasons people get a type of lung disease called bullous emphysema are smoking and a genetic condition that runs in families known as alpha-1 antitrypsin deficiency, or A1AD for short. But, it isn’t only caused by these factors. Less commonly, bullous emphysema can also be caused by damage to small air sacs in the lungs called alveoli due to things like smoking marijuana or crack cocaine, or due to illegal drug use involving needles.
Risk Factors and Frequency for Bullous Emphysema
Bullous emphysema is a condition that impacts more than 5% of the global population. Notably, its prevalence jumps to nearly 12% in adults over 30 years old. In the United States, this disease ranks as the third leading cause of death, claiming over 120,000 lives each year.
Signs and Symptoms of Bullous Emphysema
Bullae of lung disease is often associated with the main symptom of breathlessness. However, it’s worth noting that not all patients exhibit symptoms. People who experience difficulty breathing, especially when it starts to interfere with daily activities, might need surgery. This is often the case when the bullae (air-filled spaces in the lungs) take up more than 30% of a side of the chest. The disease is common in long-term smokers, who may also experience a persistent cough, often referred to as a “smoker’s cough.” This cough often tends to be worse in the mornings.
As the disease progresses, patients may experience breathing difficulties even with minor physical activities or start to wheeze. The disease often leads to physical changes such as a typical barrel-shaped chest and an enlargement of the front-to-back chest diameter. An unusually loud second heart sound, known as a P2 heart sound, is also common and is a sign of high blood pressure in the lungs. Other symptoms can include “clubbing” (changes in the shape) of the fingers and swelling due to decreased output from the right side of the heart.
- Difficulty breathing
- Persistent cough, often worse in the morning
- Breathing difficulties during physical activities
- Wheezing
- Barrel-shaped chest
- Loud P2 heart sound
- Clubbing of the fingers
- Swelling due to decreased heart output
Testing for Bullous Emphysema
To check for emphysema, doctors regularly use pulmonary function testing. This type of test measures the amount of air you can breathe out in one second compared to the total air of a complete breath. In emphysema patients, the ratio of these two numbers is usually less than 0.7. This happens because their lungs don’t stretch and return to their original shape as well as they should.
Also, patients with emphysema often have larger total lung capacity and leftover air volume when they breathe out, as well as smaller breath capacity. There’s usually a reduction in their lungs’ ability to transfer carbon monoxide, resulting from damage to the lung tissue.
In cases where a young patient shows signs of emphysema, a test for alpha1-antitrypsin deficiency may be useful. This is a genetic condition that can lead to the disease.
An X-ray of the chest would often show a flattened diaphragm due to overexpansion of the lungs. An Electrocardiogram (EKG), which records the electrical signals in your heart, may mark abnormal growth or stress in the heart’s chambers. A blood test might also reveal increased red blood cells and packed cell volume due to long-term lack of oxygen, and higher bicarbonate level in the blood due to the body trying to balance the acid build-up that happens with breathing issues.
Treatment Options for Bullous Emphysema
Chronic medical treatment involves several steps. Firstly, a quick-acting drug like albuterol is crucial for immediate relief from difficulty breathing and widening the airways. Secondly, drugs known as anti-muscarinic agents – such as tiotropium, ipratropium, and umeclidinium – help by reducing mucus, decreasing airway constriction, and preventing too much fluid production in the air tubes. Long-acting drugs, like salmeterol and formoterol, can be used but always in conjunction with other treatments, never alone.
In addition, vaccines are important. Initially, a vaccine against pneumococcal bacteria (a cause of pneumonia) should be given, followed by another one year later. Also, a yearly flu shot is recommended. Quitting smoking can slow the disease progression and reduce death risk. Long-term oxygen therapy might be needed if the patient’s oxygen levels drop below certain levels while walking.
Acute flare-ups should be treated with oxygen, a combination of albuterol and ipratropium, and steroids. Short five-day courses of prednisone, a steroid drug, can be beneficial. It’s also important to check for high carbon dioxide levels in the blood and to use a chest X-ray to investigate for lung complications like a collapsed lung or new infection requiring antibiotics. It’s also advisable to look into possible triggers of these flare-ups, like respiratory infections.
For bubble-like lesions in the lung called bullous emphysema, sometimes surgery is needed. Indicators for surgery include moderate to severe difficulty breathing, a large lesion taking up more than 30% of one side of the chest, and complications like collapsed lung, infection, and coughing blood. Sometimes, when medical treatment is not enough, surgical procedures such as lung volume reduction surgery (LVRS) and lung transplantation may be required.
One option for these patients is LVRS. This surgery involves removing part of the diseased lung tissue. This is believed to work by decreasing the size of over-inflated lungs, improving air flow. Studies have shown that after LVRS, the lungs may regain some of their elasticity which in turn improves the air flow. There are several criteria that need to be met to be eligible for LVRS, including significant obstruction to air flow that can be shown on lung tests, evidence of air trapping on lung volume measurements, and specific findings on a CT scan.
What else can Bullous Emphysema be?
When a doctor is trying to diagnose bullous emphysema, they need to consider other medical conditions that can have similar symptoms. These could be:
- Asthma, which can usually be recognized via lung function tests
- Bronchiectasis, a condition that often shows up on medical imaging
- Congestive heart failure, a serious heart condition
It’s crucial for the doctor to take these possibilities into account and perform necessary tests to make sure they arrive at the correct diagnosis.
Possible Complications When Diagnosed with Bullous Emphysema
Complications of bullous emphysema can be quite serious, and include a condition called pneumothorax. Pneumothorax happens when a bullous bleb, a kind of blister on the lung, ruptures and releases air into the chest cavity. Depending on how it occurs, a pneumothorax can be categorized as spontaneous, traumatic, or tension.
Preventing Bullous Emphysema
The most effective method to prevent bullous emphysema, a lung condition, is by avoiding smoking. As smoking is the leading cause of this health complication, most emphysema sufferers are found to have a history of smoking. Hence, if someone is diagnosed with emphysema, it’s crucial for them to stop smoking. Furthermore, everyone, regardless of their health condition, should be advised against smoking as a preventative measure.
