Health Topics: / Bronchitis

What Is Bronchitis?

Bronchitis is a respiratory disease in which the mucus membrane in thelungs' bronchial passages becomes inflamed.

As the irritated membrane swells and grows thicker, it narrows or shuts off the tiny airways in the lungs, resulting in coughing spells that may be accompanied by phlegm and breathlessness.

The disease comes in two forms: acute (lasting from one to three weeks) and chronic (lasting at least 3 months of the year for two years in a row).

People with asthma may also have asthmatic bronchitis, inflammation of the lining of the bronchial tubes.

Bronchitis is an inflammation of the lining of your bronchial tubes, which carry air to and from your lungs. People who have bronchitis often cough up thickened mucus, which can be discolored. Bronchitis may be either acute or chronic.

Often developing from a cold or other respiratory infection, acute bronchitis is very common. Chronic bronchitis, a more serious condition, is a constant irritation or inflammation of the lining of the bronchial tubes, often due to smoking.Acute bronchitis usually improves within a few days without lasting effects, although you may continue to cough for weeks. However, if you have repeated bouts of bronchitis, you may have chronic bronchitis, which requires medical attention. Chronic bronchitis is one of the conditions included in chronic obstructive pulmonary disease (COPD)For either acute bronchitis or chronic bronchitis, signs and symptoms may include:

  • Cough
  • Production of mucus (sputum), which can be clear, white, yellowish-gray or green in color — rarely, it may be streaked with blood
  • Fatigue
  • Shortness of breath
  • Slight fever and chills
  • Chest discomfort

Acute bronchitis

Acute bronchitis is a shorter illness that commonly follows a cold or viral infection, such as the flu. It consists of a cough with mucus, chest discomfort or soreness, fever and sometimes shortness of breath. Acute bronchitis usually lasts a few days or weeks.

Chronic bronchitis

Chronic bronchitis is a serious, ongoing illness characterized by a persistent, mucus-producing cough that lasts longer than three months. People with chronic bronchitis have varying degrees of breathing difficulties and symptoms may get better and worse during different parts of the year. If chronic bronchitis occurs with emphysema, it may becomechronic obstructive pulmonary disease (COPD).

What causes bronchitis?

Bronchitis is caused by the inflammation of the bronchial tubes, by viruses, bacteria and other irritant particles.

Causes of acute bronchitis

Virus infection
Bronchitis is usually caused by viral infection.

Acute bronchitis is normally caused by viruses, typically those that also cause colds and flu.

It can also be caused by bacterial infection and exposure to substances that irritate the lungs, such as tobacco smoke, dust, fumes, vapors and air pollution.

Causes of chronic bronchitis

Chronic bronchitis is caused by repeated irritation and damage of the lung and airway tissue. Smoking is the most common causes of chronic bronchitis, with other causes including long-term exposure to air pollution, dust and fumes from the environment, and repeated episodes of acute bronchitis.

Symptoms of bronchitis

Signs and symptoms for both acute and chronic bronchitis include:

  • Persistent cough, which may produce mucus
  • Wheezing
  • Low fever and chills
  • Chest tightening
  • Sore throat
  • Body aches
  • Breathlessness
  • Headaches
  • Blocked nose and sinuses.
Man coughing
Bronchitis is characterized by persistent coughing.

One of the main symptoms of acute bronchitis is a cough that lasts for several weeks. It can sometimes last for several months if the bronchial tubes take a long time to fully heal.

It is common for the symptoms of chronic bronchitis to get worse two or more times every year, and they are often worse during the winter months.

However, a cough that refuses to go away could also be a sign of another illness such as asthma or pneumonia.

Diagnosis of bronchitis

Your doctor will ask you about your symptoms, and in particular your cough. They may also ask about your medical history, whether you have recently suffered from a cold or flu, whether you smoke or whether you have recently been exposed to substances such as dust, fumes, vapors or air pollution.

Your doctor will usually use a stethoscope to listen for any abnormal sounds in your lungs. They may also examine your mucus or test the oxygen levels in your blood, and may recommend that you have a chest X-ray, pulmonary lung function test or blood tests.§  Acute bronchitis is inflammation of the bronchial tubes.

§  The most common cause of acute bronchitis is a viral or bacterial infection, but other causes may include irritants like tobacco smoke, air pollution, or chemicals.

§  The primary symptom of acute bronchitis is a cough. Other symptoms may include:

o    sputum production,

o    sore throat,

o    nasal congestion,

o    headache,

o    muscle aches, and

o    fatigue.

§  Children with acute bronchitis may have symptoms of:

o    a runny nose,

o    mild fever, and

o    cough up sputum or vomit mucus.

§  Acute bronchitis can be contagious, however, acute bronchitis caused by exposure to pollutants, tobacco smoke and other chemicals is not contagious

§  Acute bronchitis is diagnosed by the patient's history, physical exam, and possibly procedures or tests.

§  Some home remedies may relieve bronchitis symptoms.

§  Some medications may relieve bronchitis symptoms, for example, cough suppressants, NSAIDs, acetaminophen, and antibiotics (for bacterial infections only). In children under age 2, a pediatrician should be consulted before OCT medicines are used. 

§  Bronchitis is an inflammation of the bronchial tubes, the airways that carry air to your lungs. It causes a cough that often brings up mucus. It can also cause shortness of breath, wheezing, a low fever, and chest tightness. There are two main types of bronchitis: acute and chronic.

§  Chronic bronchitis is one type of COPD (chronic obstructive pulmonary disease). The inflamed bronchial tubes produce a lot of mucus. This leads to coughing and difficulty breathing. Cigarettesmoking is the most common cause. Breathing in air pollution, fumes, or dust over a long period of time may also cause it.

§  To diagnose chronic bronchitis, your doctor will look at your signs and symptoms and listen to your breathing. You may also have other tests.

§  Chronic bronchitis is a long-term condition that keeps coming back or never goes away completely. If you smoke, it is important to quit. Treatment can help with your symptoms. It often includes medicines to open your airways and help clear away mucus. You may also need oxygen therapy. Pulmonary rehabilitation may help you manage better in daily life.

§  Blood gas measurements are used to evaluate a person's lung function and acid/base balance.

§  They are typically ordered if someone is having worsening symptoms of a respiratory problem, such as difficulty breathing or shortness of breath, and a condition such as asthma or chronic obstructive pulmonary disease (COPD) is suspected. Blood gases may also be used to monitor treatment for lung diseases and to evaluate the effectiveness of supplemental oxygen therapy.

§  Blood gases are used to detect an acid-base imbalance, such as can occur with kidney failure, heart failure, uncontrolleddiabetes, severe infections, and drug overdose. They may be ordered along with other tests, such as electrolytes to determine if an electrolyte imbalance is present, glucose to evaluate blood sugar concentrations, and BUN and creatininetests to evaluate kidney function.

§  When is it ordered?

§  A blood gas analysis is ordered when someone has symptoms of an oxygen/carbon dioxide or pH imbalance, such as difficulty breathing, shortness of breath, nausea, or vomiting. It may also be ordered when someone is known to have a respiratory, metabolic, or kidney disease and is experiencing respiratory distress.

§  When someone is "on oxygen" (ventilation), blood gases may be measured at intervals to monitor the effectiveness of treatment. Other treatments for lung diseases may also be monitored with blood gases.

§  Blood gases may also be ordered when someone has head or neck trauma, which may affect breathing, and when someone is undergoing prolonged anesthesia – particularly for cardiac bypass surgery or brain surgery – to monitor blood gases during, and for a period after, the procedure.

§  Checking blood gases from the umbilical cord of a newborn may uncover respiratory problems as well as determine acid/base status. Testing is usually only done if a newborn is having difficulty breathing.

What does the test result mean?

Normal values will vary from lab to lab. They are also dependent on elevation above sea level as a person's blood oxygen level will be lower if they live higher than sea level.

Results from an arterial blood gas analysis are not diagnostic; they should be used in combination with the results of other tests and exams to evaluate someone for a respiratory, metabolic, or kidney problem.

Abnormal results of any of the blood gas components may indicate one or more of the following issues:

·         A person is not getting enough oxygen

·         A person is not getting rid of enough carbon dioxide

·         There is a problem with a person's kidney function

A low partial pressure of oxygen (PaO2) suggests that a person is not getting enough oxygen, while results that are within normal range usually mean that oxygen intake is sufficient.

All other components of the blood gas analysis (pH, PaCO2, HCO3-) are interrelated and the results must be considered together. Certain combinations of results, if abnormal, may indicate a condition that is causing acidosis or alkalosis. These may include the following:

·         Respiratory acidosis is characterized by a lower pH and an increased PaCO2 and is due to respiratory depression (not enough oxygen taken in and carbon dioxide removed). This can be caused by many things, including pneumonia,chronic obstructive pulmonary disease (COPD), and over-sedation from narcotics.

·         Respiratory alkalosis, characterized by a raised pH and a decreased PaCO2, is due to over-ventilation caused by hyperventilating, pain, emotional distress, or certain lung diseases that interfere with oxygen exchange.

·         Metabolic acidosis is characterized by a lower pH and decreased HCO3-, causing the blood to be too acidic for proper metabolic/kidney function. Causes include diabetes, shock, and renal failure.

·         Metabolic alkalosis is characterized by an elevated pH and increased HCO3- and is seen in hypokalemia, chronic vomiting (losing acid from the stomach), and sodium bicarbonate overdose.

Examples of test results associated with the above conditions are summarized below:

pH result

Bicarbonate result



Common causes

Less than 7.35



Metabolic acidosis

Kidney failure, shock, diabetic ketoacidosis, intoxication with methanol, salicyate, ethanol

Greater than 7.45



Metabolic alkalosis

Chronic vomiting, low blood potassium, heart failure, cirrhosis

Less than 7.35



Respiratory acidosis

Narcotics, lung diseases such as asthma, COPD, airway obstruction

Greater than 7.45



Respiratory alkalosis

Hyperventilation, pain, anxiety, brain trauma, pneumonia, certain drugs (salicylate, catecholamines)

If left untreated, these conditions can create an imbalance that can eventually become life-threatening. A health practitioner can provide the necessary medical intervention to regain normal acid/base balance, but the underlying cause of the imbalance must also be addressed.

Is there anything else I should know?

Arterial blood sample collection is usually a bit more painful than regular venipuncture. You may experience moderate discomfort, and a compress is required for some time to prevent any bleeding from the site.

Sometimes mixed venous blood taken from a central line is used in particular situations, such as in cardiac catheterization labs and by transplant services. Careful interpretation of the results is required. Peripheral venous blood, such as that taken from a vein in the arm, is of no use for oxygen status because it has decreased oxygen content due to the fact that it is composed of blood returning .Image result for bronchitisImage result for bronchitisImage result for bronchitisImage result for bronchitisImage result for bronchitisImage result for bronchitisImage result for bronchitisImage result for bronchitis


Treatments for bronchitis

People suffering from bronchitis are usually instructed to rest, drink fluids, breath warm and moist air and take over-the-counter cough suppressants and pain relievers in order to manage symptoms and ease breathing.

Many cases of acute bronchitis may go away without any specific treatment, but there is no cure for chronic bronchitis.

To keep bronchitis symptoms under control and relieve symptoms, doctors may prescribe:

Cigarette being snapped
As cigarette smoking is the most common cause of chronic bronchitis, avoiding smoking is one of the best ways to prevent it.
  • Antibiotics - these are effective for bacterial infections, but not for viral infections. They may also prevent secondary infections
  • Cough medicine - although coughing should not be completely suppressed as this is an important way to bring up mucus and remove irritants from the lungs
  • Bronchodilators - these open the bronchial tubes and clear out mucus
  • Mucolytics - these thin or loosen mucus in the airways, making it easier to cough up sputum
  • Anti-inflammatory medicines and glucocorticoid steroids - these are for more persistent symptoms to help decrease chronic inflammation that may cause tissue damage
  • Oxygen therapy - this helps improve oxygen intake when breathing is difficult
  • Pulmonary rehabilitation program - this includes work with a respiratory therapist to help improve breathing.

Additional behavioral remedies include:

  • Removing the source of irritation to the lungs - for example, by stopping smoking
  • Using a humidifier - this can loosen mucus and relieve limited airflow and wheezing
  • Exercise - this will strengthen the muscles involved in breathing
  • Breathing exercises - for example, pursed-lip breathing that helps to slow breathing down.


Although you cannot always prevent acute bronchitis or chronic bronchitis there are several measures that can be taken to reduce your risk of both conditions:

  • Do not start smoking; quit smoking if you already smoke
  • Avoid lung irritants, such as smoke, dust, fumes, vapors and air pollution. If you cannot avoid exposure to these, wear a mask that covers your nose and mouth
  • Wash your hands often, to limit your exposure to germs and bacteria
  • Get a yearly flu vaccine
  • Get a pneumonia vaccine.

In a study in Lebanon, exposure to passive smoking at work was associated with almost double the risk of chronic bronchitis (an 89% increased odds ratio), while passive smoking at home was associated with more than two-and-a-half times (Odds Ratio: 2.59) the risk of chronic bronchitis.

Image result for bronchitis

MNT/Mayo clinic/

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