What is Emphysema?
It is a chronic and progressive respiratory disease that causes over-inflation of the air sacs in the lung (alveoli) . The over-inflation of the alveoli causes it to lose its elasticity which may lead to alveolar rapture or lung collapse (atelectasis) .
Alveolar Gas Exchange
The lungs are the organs in the body which are primarily responsible for the gas exchange. The process involves the oxygen and carbon dioxide which are exchanged between the air breathed in and the blood.
Alveoli are part of the lungs which look familiar to tiny air sacs. These air sacs are lined with thin, elastic walls. Along the alveolar walls are the capillaries. These are the tiniest of the blood vessels. They allow the blood and air to come together. Then, the small distance, separating the air in the lungs and the blood in capillaries, allows the transfer of oxygen and carbon dioxide molecules across the walls.
As the lungs breathe in, the air goes into the lungs and the alveoli expand. Once this happens, oxygen attaches to the hemoglobin molecules of the red blood cell. Then, it circulates throughout the body for use. After that, carbon dioxide, a waste product, detaches and later on exits the alveoli to be exhaled. As we breathe out, the air sacs constrict or squeeze to push the air out of the lungs. 
Picture 1: Alveolar Gas Exchange
Pathophysiology: What Happens in Emphysema?
The occurrence of emphysema is most commonly caused by the toxins coming from the cigarette smoke. The toxins coming from the cigarette chemicals affect the lungs by damaging the linings of the lung air sacs (alveoli). Over the years, when cigarette smoking is still done by the patient, the following happens:
- As the toxins, coming from the cigarette smoke, do its damage on the delicate linings of the alveoli, air pockets start to form in the lungs.
- The air inhaled becomes trapped in these pockets.
- Aside from that, the lung tissue holding the small airways (bronchioles) fails to do its proper function. Normally, it should be held open by the lung tissues, but due to the damage created by the cigarette chemicals, the airways collapse. This contributes to the trapping of air in the alveoli.
- Emphysema also causes destruction of the spongy tissue of the lung. This means that the alveoli lose its elasticity and ability to bring back to its resting state.
- The above mentioned impacts the ability of the lungs to empty the air sacs.
- This effect of emphysema is referred to as airflow limitation. For most patients with emphysema, it requires more effort for them to exhale the air that is present in their lungs.
- The damage caused by Emphysema to the lungs is irreversible and leads to the appearance of holes in the lung tissues. [1, 4, 5]
Picture 2: Illustration of the comparison between a healthy and diseased alveoli
What Causes Emphysema?
Emphysema may occur as the result of one or a combination of the following [1, 3, 4, 5, 6]:
- Most of the Emphysema cases are related to smoking. This is the most dangerous behaviour which could lead to the development of the disease.
- This is the single most preventable cause of emphysema.
- Cigarette smoking contributes to the disease in two ways: First, it causes damage to the lung tissue. This results to the air flow obstruction. Second, the chemicals coming from the smoke cause inflammation and irritation. This aggravates the condition of the lungs.
- There are studies which show that the smokers who smoke six times more in a day are more prone to developing Emphysema.
2. Exposure to air pollution
- Dust, chemical fumes, other substances
- Irritating fumes and dusts
- Secondhand smoke: The exposure to the cigarette smoke has been proven to have a bad effect on lungs. There are studies which show that people who are exposed to the cigarette smoke coming from firsthand smokers are at higher risk to developing the disease.
3. Alpha-1 antitrypsin deficiency
- This is a rare genetic disorder wherein a person lacks alpha-1 antitrypsin. This enzyme is responsible for protecting the lungs. People who have this condition can acquire emphysema without even smoking.
- Another factor that contributes to emphysema occurrence is aging. As people age, the lungs deteriorates little by little. The elastic properties of the lungs decrease. As a result, tensions can develop in the lungs with emphysema.
5. Immune deficiencies
- For some immunodeficiencies, infections such as Pneumocystis carinii, can exacerbate the inflammation in the lungs.
6. Intravenous drug use
- Infusing non-drug additives like cornstarch intravenously can cause damage to the lung tissues.
7. Connective Tissue Illnesses
- Marfan Syndrome, Ehlers-Danlos syndrome
- These illnesses cause failure of the elastic tissues in the body to function properly. Therefore, affecting the alveoli to fail.
Emphysema Signs and Symptoms
Picture 3: A patient with a barrel-shaped chest
- Barrel chest
- Rales: This breath sound indicates presence of lung infection or inflammation
- Decreased vocal/tactile fremitus or decreased respiratory movement
- Abnormal heart sounds: distant heart sounds, abnormal heart sound below the xiphoid process. This is usually indicative of pulmonary heart disease.
- Decreased breath sounds, prolonged exhalation 
- Cough and Sputum: These two occur due to the lung inflammation and infection. Usually, smokers cough after waking up. This is also known as the “smoker’s cough”. The sputum appears white and foamy. If the emphysema is associated with bacterial infection, it would look yellow, sticky, and have a foul smell.
- Difficulty in breathing: This is the most prominent symptom of emphysema. This may vary depending on the severity of the disease. It starts in the form of shortness of breath during some physical activities like climbing the stairs or exercising.
- Pursed-lip breathing: Most patients with emphysema present with this. This refers to the instance when a person with emphysema tries hard exhale the trapped air in the lungs. The patients do this by pursing their lips. This is done by most of them because it allows the release of the trapped air in their lungs. [1, 6, 7]
Picture 4: An illustration of how the lungs look like during pursed-lip breathing
- Weight loss
- Sleep problems
- Heart problems
- Depression 
Emphysema Diagnosis and Tests
1. Medical Interview
- The doctor may ask questions about the patient’s smoking status and history, what are the symptoms felt by the patient. 
2. Physical Exam
- This would include auscultation or listening to the heart, lung, and breath sounds.
- The doctor will determine if the patient is having shortness of breath, if the patient is using intercostals muscles or accessory muscles are used to breathe.
- Aside from the doctor will assess for chest indrawing, barrel shaped chest, decreased diaphragm movement, wheezing, and cyanosis. [3, 6]
3. Imaging studies
- Xray: This is used to confirm the diagnosis for the cases of advanced emphysema. This would also rule out why the patient has been experiencing shortness of breath A plain chest x-ray would indicate emphysema when the lungs are shown to be inflated. Also, it has abnormal chest markings.
Picture 5: Chest X-ray of a person with Emphysema
- CT Scan: This is done in tandem with chest x-ray to create several images showing cross-sectional views of the internal organs. This would be very much needed if the doctor is considering performance of lung surgery. [3, 9]
4. Lab Tests
- Blood tests: This test may be used for checking the level of white blood cells, which can indicate the presence of an infection. A complete blood count is also helpful in checking the number of red blood cells. This aids in indicating if the blood is getting adequate oxygen.
- ABG (Arterial Blood Gas): This test measures the amount of oxygen and carbon dioxide in the blood. It mainly helps the health care providers to determine the oxygen concentrations in the body.
- Electrocardiogram (ECG): It is performed for recording the electrical activity of the heart. The test also may show abnormal heart rhythms and if there is heart muscle damage related to emphysema.
- Sputum culture: This obtained by asking the patient to cough up from the lungs into the mouth. This is done to rule out any presence of infection.
- Anti-trypsin test: This is an examination done to aid in diagnosis of the early onset emphysema. This is ordered by the doctor if the patient has no obvious risk factors such as smoking or exposure to lung irritants. [1, 3, 5, 10]
5. Pulmonary Function Tests
These are series of tests that involve the measurement of the pulmonary ability to exchange oxygen and carbon dioxide properly. These are performed using several machines where the patient breathes into.
- Spirometry: This is a device which can evaluate the lung function. It is recommended to be used for various reasons like diagnosing the lung disease (whether it is restrictive or obstructive), examining the lung condition, and if the treatment used is effective.
Picture 6: How Incentive Spirometry is done
- Peak Flow Monitoring: A device which is intended to determine the fastest speed that the patient is able to blow air out of the lungs. This is a great test for evaluating if the disease is controlled or not. 
Picture 7: How Peak Flow Monitoring is performed
The main goal for the treatment of emphysema is to provide the patient with comfortable living. This is done by alleviating the symptoms as well as preventing the progression of the disease. 
1. Smoking Cessation
Though this is not really a treatment, many doctors advice most of the patients to quit smoking. Smoking cessation will help in the improvement of the lung condition. The doctor can even suggest drugs which could break the addiction to smoking. The patient may also be suggested to participate in behavioural therapies such as support groups. 
- Bronchodilators: These are usually used for patients with asthma, but this is also recommended for emphysema patients. These medications help in relaxing the muscles around the airway. Thus, it relieves the airway constriction which enables them patients to breathe easier. These medicines are in the form of inhalants, nebulisations, and oral syrups or tablets.
- Steroid Medications/Anti-Inflammatory Drugs: This type of medication is also known as corticosteroids. These are given to treat lung inflammation. Not all patients are responsive to steroid treatment.
- Antibiotics: Antibiotics is often prescribed for patients who experience shortness of breath. Even if the x-rays of these patients do not show presence of infection, antibiotics seem to aid in relieving their shortness of breath. This is also a good treatment for those patients that have infections. [1, 11]
- Supplemental Oxygen: This is prescribed for patient who are experiencing shortness of breath or those who are not getting enough oxygen to their blood (hypoxemia).Patients who are undergoing the oxygen therapy would be hooked to a pulse oximeter and be tested using arterial blood gas tests to determine the effectiveness of the treatment.
- Pulmonary Rehabilitation: This rehab program includes teaching patients about proper breathing exercises and techniques. This is totally beneficial in helping them breathe better and their ability to perform tasks. Also, some patients are required to lose weight. However, this is only recommended for patients who are in the early stage of emphysema. [9, 11]
4. Lung surgery
- Lung volume reduction surgery: This surgery involves removal of 35% of the diseased lung tissue. Then, the remaining tissues will be joined together. As a result, this would eliminate the pressure on the breathing muscles. Aside from that, lung elascity will be improved.
- Lung transplant: This is an option if all other management have failed. [9, 11]
Emphysema Stages and Life Expectancy
The life expectancy of patients diagnosed with emphysema depends on many factors. The two most important factors that the doctors determine here are the stage of emphysema and the kind of treatment that will be used . The stages of emphysema are determined using Pulmonary Function Testing (PFTs). This test indicates if there is a pulmonary obstruction and how much air a person can exhale in one second . There are four stages of emphysema, then, each stage has a corresponding life expectancy and treatment.
Stage 1 (Mild)
A person who has been diagnosed with Stage 1 emphysema has the same life expectancy as any normal person does. As long as the condition is managed early and appropriately, the symptoms are usually controlled easily. It is also advisable for these patients to avoid smoking to control emphysema and prevent it from progressing to later stages.
Stage 2 (Moderate)
Patients diagnosed with Stage 2 emphysema are expected to live 5 years or more. But this is possible with the help of intensive treatments and smoking cessation.
Stage 3 (Severe)
For people with Stage 3 emphysema, life expectancy significantly drops. Most of them will not be able to survive more than four years. For the later stages of emphysema, patients are given supplemental oxygen to help them in their breathing. This is given because they have low blood oxygen levels. Also, oxygen therapy is given together with bronchodilators.
Stage 4 (Very Severe)
Just like the patients with Stage 3 emphysema, patients who are in Stage 4 of emphysema are also expected to have a hard time living more than four years. They are also hooked to supplemental oxygen on a 24 hour a day basis which is incorporated to the bronchodilators that are administered to them as well. Though most treatments are continued for these patients, prolonging their life will still be a challenge to the doctor since it is the most advanced stage of emphysema. [12, 14]
Points to Consider
Smoking has lots of harms to the body. Though this is the case, still, many of us continue smoking. It’s hard to suffer in the end when all of the effects of smoking occur. A change to lifestyle is much needed, especially, for emphysema and chronic bronchitis patients since the primary cause of their disease is smoking. It’s never too late to quit smoking. It’s never late to save your life and other’s life too.
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