Atelectasis - Types, Causes, Risk Factors, Symptoms, Diagnosis and Treatment

Introduction:

You breathe with the help of branching tubes that run through the lungs. When you inhale air, it moves and reaches the lungs through the windpipe. This windpipe progressively branches out into smaller tubules and ends in very small air sacs called alveoli. These alveoli exchange the oxygen in the air that you breathe in with the carbon dioxide produced in the body. For this to happen, the alveoli must be inflated. But, when these alveoli get deflated or filled with alveolar fluid, either the entire lung collapses, or a lobe of it does, which is called atelectasis.

It can occur as a complication of other respiratory problems, such as lung cancer, cystic fibrosis, chest injury, pulmonary edema (fluid in the lung), or due to breathing in a foreign object. It is one of the commonest breathing complications a person experiences after surgery. If the patient has a pre-existing lung disease, this condition worsens it and makes breathing extremely difficult. The treatment depends on what caused it and how severe it is. This condition is not usually life-threatening, but it needs immediate treatment sometimes.

What Is the Difference Between Pneumothorax and Atelectasis?

A collapsed lung is also called pneumothorax. This collapse happens when air is stuck in between the inner chest wall and outside of the lung. This air shrinks the lungs and eventually leads to its collapse. This collapsed lung can also deflate the alveoli, resulting in atelectasis.

What Are the Signs and Symptoms of Atelectasis?

Atelectasis can result in no to mild to severe symptoms. This depends on the areas of the lung that are affected, and the speed with which it develops. There are usually no symptoms if only a few alveoli are involved. When many alveoli are affected, oxygen does not get effectively exchanged, which leads to a deficiency of oxygen in the body. The signs and symptoms that might suggest that your body is not getting enough oxygen are:

1. Breathing difficulty.

2. Chest pain, which is sharp and occurs while taking a deep breath.

3. Rapid breathing.

4. The heart beats fast, which increases the heart rate.

5. The skin, lips, and nails might turn bluish.

In some cases, pneumonia might develop. If you have developed pneumonia, you might have:

1. Productive cough.

2. Chest pain.

3. Fever.

4. Shortness of breath.

What Are the Types of Atelectasis?

Based on the causes, atelectasis is divided into:

1. Obstructive Atelectasis - It is due to a blockage in the airway, which prevents air from reaching the alveoli.

2. Non Obstructive Atelectasis - This includes all other types of atelectasis that are not caused by a blockage in the airway.

What Are the Causes of Atelectasis?

Anything that blocks the air passage can cause obstructive atelectasis. It includes:

• Inhaling foreign objects like food, a small toy, etc.

• Any tumor in the airway.

• Any tumor in the lung that compresses the airway.

• Accumulation of mucus (mucus plug) in the airway.

The causes of nonobstructive atelectasisare:

• Surgery - It commonly occurs during or after any surgery. This is because anesthesia and the breathing machine used during surgery makes the breathing shallow, which makes the patient less likely to cough, even if the need arises. This inability to clear your airway by coughing accompanied by shallow breathing can result in some of the alveoli to collapse.

• Chest Injury - Any kind of trauma, such as a car accident or a fall, can result in atelectasis.

• Pleural Effusion - It is the collection of fluid in the space between the outer lining of the lung and the inner lining of the chest wall. These linings should be in close contact to facilitate lung expansion. When the fluid gets accumulated, the linings separate, which puts pressure on the lungs and results in deflating of the alveoli.

• Chest Cancer - Chest tumor or any growth near the lungs can compress it, forcing the air out of the alveoli.

• Surfactant Deficiency - Each alveolus contains a surfactant, which keeps it open. When this surfactant is less, the alveoli collapse. This is commonly seen in babies born prematurely.

• Pneumothorax - As explained before, the collection of air in between the linings of the lung and chest is called pneumothorax. This also squeezes your lungs and deflates the alveoli.

• Pulmonary Fibrosis - It is the scarring of the lung. It can result from lung infections (such as tuberculosis or pneumonia) and prolonged cigarette smoking. Scarring diminishes the capacity of alveoli to inflate.

What Are the Risk Factors of Atelectasis?

Some factors that might increase the risk of atelectasis are:

1. Old age.

2. Certain medications that make breathing shallow.

3. Chronic smoking.

4. People on bed rest.

5. Lung conditions like asthma, COPD (chronic obstructive pulmonary disease), etc.

6. Abdominal or chest surgery.

7. General anesthesia.

8. Weak respiratory muscles.

How Does a Doctor Diagnose Atelectasis?

The doctor can diagnose this condition with the help of a chest X-ray. But, you may need to get other tests done to know the cause and severity:

1. Oximetry - A small device is placed on a finger, which measures the blood-oxygen level. Based on this, the doctor knows how well your lungs are functioning.

2. Chest Ultrasound - This is done to rule out other conditions like lung consolidation and pleural effusion.

3. CT (Computed Tomography) of the Chest - This gives a clearer image of the lungs, which might help the doctor detect the cause of atelectasis.

4. Bronchoscopy - Here, a flexible tube is inserted through the throat to see if there are any blockages in the airway.

What Are the Treatment Options for Atelectasis?

The doctor will decide the best treatment option based on the cause and severity. The treatment options include:

1) Physiotherapy - It is used to treat obstructive atelectasis, especially after surgery. The body is moved in different positions, and the chest is tapped and vibrated to loosen and drain mucus.

2) Breathing Exercises - Exercises that make you take deep breaths are done. Deep breathing helps the alveoli to open up.

3) Bronchoscopy - While looking for any foreign object that might be blocking your airway using a bronchoscope, the doctor might also remove the cause.

4) Drainage - The doctor might drain fluid or air collected between your lungs and chest wall if the cause is pneumothorax or pleural effusion.

5) Surgery - In some cases, a lobe or small area of the lung needs to be surgically removed. This is only done if all the non-surgical treatment options fail.

What Are the Complications of Atelectasis?

The following are some possible complications from atelectasis:

• Pneumonia - Mucus buildup can result in infection and pneumonia.

• Hypoxemia - Low oxygen level in the blood.

• Respiratory Failure - If the entire lung collapses, especially in an infant, it can result in failure to breathe.

How Is Atelectasis Prevented?

You might be able to prevent atelectasis if you:

1. Cough and do deep breathing exercises after surgery.

2. Quit smoking.

3. Use an incentive spirometer to take deep breaths after major surgery.