Bronchospasm - Causes, Symptoms, Diagnosis, and Treatment

Introduction

Bronchospasm is a common condition in children and adults. Bronchospasm refers to the tightening of the muscles that line the airway. This causes narrowing of the airway and causes shortness of breath. It results in wheezing, coughing, and other symptoms. It occurs in asthma, chronic bronchitis, and anaphylaxis.

What Is Bronchospasm?

The main airway (trachea) branches off into the right and left primary bronchi into the lungs. The primary bronchus branches into secondary and tertiary bronchus in the lungs. The tertiary bronchus further divides into smaller bronchioles. This further divides into terminal bronchioles, which further divide into alveolar ducts associated with alveolar sacs. The bronchus and the bronchioles are lined with smooth muscles. Bronchospasm is the tightening of the muscles that line the bronchi and bronchioles, narrowing the airway and causing difficulty breathing.

How Does Bronchospasm Occur?

External stimulus triggers the constriction of the bronchial muscles. Mast cells and basophils are involved in constriction under the influence of anaphylatoxins. These cells release certain substances that constrict the airway. This results in narrowing the airways and increased mucus production, reducing the amount of oxygen essential for breathing. This leads to breathlessness, coughing, and hypoxia.

What Are the Effects of Bronchospasm?

Respiration comprises ventilation - breathing in oxygen and breathing out carbon dioxide; diffusion - exchange of oxygen and carbon dioxide at the alveoli of the lungs and pulmonary capillaries; and perfusion - pumping of blood with oxygen throughout the body. Bronchospasm interferes with the mechanism of respiration and disrupts the normal function of the respiratory system.

What Are the Causes of Bronchospasm?

Inflammation in the airway causes bronchospasm. It is common in people with asthma. Bronchospasm is a symptom of asthma, and it is different from asthma. Individuals with asthma can get bronchospasm, but everyone with bronchospasm does not get asthma. Other causes include:

• Allergens like dust particles, pollen, mold, pet dander, and other allergens.

• Conditions like chronic obstructive pulmonary disease (COPD), chronic bronchitis, and emphysema.

• Chemical fumes.

• Environmental like pollution, smoke, fragrances, and odors.

• During general anesthesia given in surgery.

• Recurrent infections due to bacteria, viruses, or fungi.

• Exercise.

• Cold weather.

• Inhalation of smoke from the fire.

• Smoking.

• In rare conditions, bronchodilators used for the treatment of bronchospasm worsen it.

• Bronchospasm is the side effect of drugs like pilocarpine and beta blockers used to treat hypertension.

• Topical decongestants like Oxymetazoline and Phenylephrine cause bronchospasm.

What Are the Symptoms?

The symptoms of bronchospasm appear suddenly. The symptoms include:

• Tightness in the chest.

• Wheezing.

• Coughing.

• Shortness of breath.

• Tiredness.

• Dizziness.

What Are the Complications of Bronchospasm?

Bronchospasm obstructs the airway and causes the following complications:

• Pneumothorax - It occurs due to the leakage of air between the lungs and the chest wall resulting in the collapse of the lungs.

• Pneumomediastinum - It is a condition wherein the air is present in the mediastinum due to injuries or other diseases.

• Acute Respiratory Failure - It is a severe condition that occurs when fluids accumulate in the air sacs or alveoli of the lungs.

• Hypoxia - It is a condition wherein insufficient amounts of oxygen are available to maintain the body's activities.

• Hypercapnia - It is characterized by an elevation in partial pressure of carbon dioxide.

How Is Bronchospasm Diagnosed?

Lung function tests are performed to diagnose bronchospasm. They include:

• Spirometry - The individual is asked to breathe into a tube connected to a spirometer device. It measures the force of the air breathed in and out.

• Lung Volume Test - This test measures the amount of oxygen the lungs can hold.

• Lung Diffusion Capacity Test - The individual is asked to breathe through a tube to measure the amount of oxygen that enters the blood. The hemoglobin level is also measured because it helps transport oxygen in the blood.

• Pulse Oximetry - A pulse oximeter is clipped onto the fingers to measure the oxygen level in the blood.

• Arterial Blood Gas Test - This test determines the levels of oxygen and carbon in the blood.

• Escaping Voluntary Test - This test is used to diagnose exercise-induced bronchospasm. This is performed to assess if breathing in oxygen and releasing carbon dioxide during exercise affects lung function.

• Chest X-ray - It is used to diagnose pneumonia and the presence of other infections.

• Computed Tomography (CT) Scan - This is used to diagnose bronchospasm and other abnormalities associated with lung function.

How Is Bronchospasm Treated?

Bronchospasm is usually managed with bronchodilators. It is available as inhalers, nebulizers, solutions, and tablets. Steroids are also prescribed to reduce inflammation in the airways.

• Short-Acting Bronchodilators - This offers quick relief from bronchospasm symptoms. These short-acting drugs widen the airway within minutes, and the effects last up to six hours. Common short-acting bronchodilators are Terbutaline, Salbutamol, and Levosalbutamol.

• Long-Acting Bronchodilators - These drugs do not offer immediate relief but reduce the occurrence of bronchospasm in the future. It exerts action after a long time, but the effect lasts up to twelve hours. Commonly used long-acting bronchodilators are Salmeterol, Formoterol, and Vilanterol. Other long-acting bronchodilators include anticholinergics that are available in short-acting (Ipratropium) and long-acting forms (Umeclidinium and Aclidinium) of inhalers.

• Steroids - Steroids are given to reduce inflammation in the airways. They are used with inhalers. It is given as tablets or via an intravenous route in severe cases of bronchospasm.

Can Bronchospasm Be Treated at Home?

Bronchospasm cannot be treated with home remedies. If bronchospasm occurs for the first time, it is important to consult the doctor immediately for treatment. Short-acting bronchodilators are given to ease the symptoms.

How to Prevent Bronchospasm?

Bronchospasm cannot be prevented, but certain measures can be followed to reduce the risk of occurrence. This include:

• Avoid smoking.

• Stay hydrated.

• Warm up before exercise.

• Limit exercise during allergies.

• Limit exercise in cold conditions.

What to Expect With Bronchospasm?

Bronchospasm lasts between seven and fourteen days. If not treated at the right time, the symptoms are life-threatening. But, with proper treatment, symptoms subside within a few minutes. Short-acting bronchodilators are given to relieve the symptoms, and long-acting bronchodilators are given to prevent the occurrence of bronchospasm. A short-acting drug should be used immediately on developing bronchospasm. Emergency help is needed in the following situations:

• Difficulty in breathing.

• Coughing up mucus with blood.

• Chest pain.

• Dizziness or fainting.

Conclusion

Bronchospasm is a treatable condition. Symptoms of bronchospasm can be severe and life-threatening. Individuals with respiratory conditions like asthma, COPD, and chronic bronchitis are more prone to bronchospasm. It is important to consult a doctor if the symptoms interfere with daily activities. Untreated bronchospasm causes inevitable symptoms. Early diagnosis and intervention can prevent the risk of complications.