Bronchitis means inflammation of your bronchial airways, and it's an immune response to something you inhaled. It’s meant to keep you healthy. Chronic simply means this inflammation is always present to some degree. It may cause a cough that seems to always be there. It may also cause colorful mucus production, throat clearing, chest tightness, and shortness of breath.
Difference Between Acute Bronchitis and Chronic Bronchitis
Chronic Bronchitis is caused by inhaling noxious substances day after day and year after year. A common cause is inhaling cigarette smoke. Another is inhaling gases, fumes, vapors, and dusts in the air at your work. Your immune system responds by causing airway inflammation. This response is similar to when you inhale a respiratory virus. But, the noxious substances continue to be introduced to your airways. Exposure to them is chronic. This causes the resulting inflammation to become chronic.
This inflammation irritates specialized cells and glands lining airways. Over time, your body thinks it can help by making more of these cells and glands. Now there are lots of them, and they are larger than normal. This causes abnormal amounts of mucus to be produced. Also, cilia lining airways become damaged. They have a hard time sweeping all this extra mucus to your upper airway. This causes some mucus to become trapped in your throat. It may tickle your cough reflex making you cough. This cough is often used to diagnose chronic bronchitis. It’s defined as a cough that persists for three consecutive months and two consecutive years.
So, now you have lots of abnormally large mucus glands and cells. This, combined chronic inflammation, makes airway walls abnormally thick. This makes airways abnormally narrow and obstructed. Excessive mucus may also further obstruct airways. Airway obstructions may impede the flow of air through them. Air can get in through obstructed airways when you inhale. But, it has a hard time getting back out when you exhale. This can make you feel short of breath. It may also cause chest tightness and wheezing.
Acute bronchitis is caused by inhaling respiratory viruses or bacteria. It may also be caused by short-term exposure to harmful substances such as cigarette smoke. Lining airways are airway epithelial cells. Their surfaces are covered with a fine layer of mucus. Mucus is a wet, sticky substance to trap pathogens, like viruses. Airway cells are also covered with fine hair-like structures called cilia. Cilia works like brooms to sweep mucus and any pathogens trapped within it to your upper airway. (
So, now let’s say you inhale a respiratory virus. Your immune system responds by causing airway inflammation. This inflammation is acute, meaning it’s happening right now. It will go away as soon as the viruses are removed. Usually this is within 10 or so days. This inflammation irritates specialized cells and glands that make mucus. It causes them to secrete extra mucus. Viruses get stuck in this mucus. They are then balled up and swept to your upper airway by cilia. As mucus reaches the back of your throat it may tickle your cough reflex making you cough. You may clear your throat. Phlegm may be swallowed and destroyed by stomach juices.
It may also be spit up and removed that way. Within ten or so days the respiratory viruses are gone. Inflammation gradually subsides and your symptoms go away. However, a cough may persist for several more days.
What Causes Chronic Bronchitis?
Exposure: It’s usually caused by inhaling noxious particles or gases day after day for many years. The most common cause is cigarette smoking. However, another potential cause is inhaling substances in the air at your work. (COPD Guidelines)
Hereditary: About 50% of people who somke don’t develop chronic bronchitis. For this reason, some experts suspect some form of genetic susceptibility. Researchers still do not know much about the genetic component of chronic bronchitis. (COPD Guidelines)
Other: There are also other potential risk factors researchers are considering. Some of these include low birth weight, sex, and age.
What Causes Chronic Bronchitis To Develop?
Neutrophils: The ones released here are the mediators of inflammation. Some mediate or directly cause airway inflammation. Others circulate the bloodstream to recruit white blood cells such as neutrophils.
Airway Inflammation: It’s caused in an effort to rid your body of harmful substances, such as chemicals in cigarette smoke. The problem here is that the harmful substance don’t go away. So, airway cells continue to release chemicals. Some are inflammatory chemicals meant to create more aggressive inflammation. Others are aimed at repairing damaged.
Airway Changes: Airway epithelial cells have a noble goal by secrecing inflammatory chemicals. It’s go get rid of harmful chemicals. But, when these chemicals stick around too long, they may actually damage the same cells they are meant to protect. So, airway cells have to repeatedly make efforts at repairing themselves. These repeated cycles of damage and repair eventually cause airway walls to become scarred. This makes airway walls thicker than normal.
Obstructions: Thicker walls obstruct the flow of air. It makes it so air can easily enter airways when you inhale. But, it slows the flow of air when you exhale. This slowing of the flow of exhaled air is called airflow limitation.
Goblet Cells: These are randomly scattered along airways. The secrete mucus. This mucus is a clear sticky substance. It’s meant to trap and kill pathogens. Your body thinks it can help rid harmful inhaled substances by increasing their numbers. So, people with COPD tend to have an abnormally large amount of goblet cells.
Mucus Glands: Like goblet cells, these also secrete mucus. These cells tend to become abnormally enlarged.
Loss of Cilia: As a result of the disease process, cilia become destroyed. This reduces their ability to move mucus to your upper airway.
Mucociliary Dysfunction: This is a combination of excessive mucus and loss of cilia. Inflammatory chemicals have a noble goal. goal is to get rid of harmful substances from your lungs. But, when they hang around too long, they can cause damage to airway cells. Inflammatory chemicals and neutrophils were recruited to airways for a noble cause: to protect airway cells from invaders. Some of these chemicals directly cause airway inflammation. Others recruit immune cells such as neutrophils.
Neutrophils: These are white blood cells. It is thought that they are the main causes of inflammation in chronic bronchits.
Symptoms of Chronic Bronchitis
Chronic bronchitis is an inflammatory airway disease. It’s usually combined with a diagnosis of emphysema. Both of these diseases are listed under the umbrella term COPD. Here are some of the most common symptoms that may be experienced.
Coughing: This is usually the first symptom observed. It’s also the most common symptom. It’s caused by increased mucus production. Mucus is brought up to your upper airway. It irritates your cough reflex making you cough. It’s often brushed off as trivial and ignored. Some people get so used to it that it tends to bother others more so than the person coughing.
Throat Clearing: As mucus collects in the back of your oral cavity it can make you feel the urge to clear your throat. Like coughing, this may also be brushed off and ignored as trivial. In fact, sometimes coughing is brushed off as "just throat clearing."
Mucus production:The cough is sometimes productive of sputum. It may be colorful. Colorful sputum may indicate an infection. But, in most cases it’s probably just the color of the types of cells in airways that are inflamed.
Wheezing: As the disease progresses, lower airways can become narrow. As air travels through narrowed airways this can make a wheezing sound. Doctors can hear this lungsound by using their stethoscopes. Sometimes it’s audible and you can hear it without the aide of a stethoscope.
Shortness of Breath: Narrowed airways obstruct the flow of air. Mucus may collect in airways to further obstsruct them. Air can easily get in past obstructions when you inhale. But, it has a hard time getting back out when you exhale. This slows the flow of exhaled air. It makes it feel like you can’t get air in. But, you actually can’t get air out. Each person with chronic bronchitis may experience this differently. Some may not experience it all all. Some may only experience it with exertion. Others may experience some degree of it even at rest.
Chest tightness: Changes occuring inside your airways sometimes cause a dull pain. This may precede feelings of shortness of breath. Sometimes it occurs alongside shortness of breath. A common cause is using accessory muscles to breathe. These are muscles not typically used to breathe. When you use them they can become sore. This is similar to what happens when you work out for the first time in a while and your muscles become sore. As with other symptoms, different people may experience this differently. Some may not experience it at all.
Fatigue: Many people with chronic bronchitis simply feel tired. But, like coughing, this is another symptoms that is often ignored and brushed off to aging. Similarly, it’s often underappreciated by doctors as a symptom of COPD. Despite this, it’s the second most common symptom.
Anxiety: This is defined as feelings of fear or apprehension due to a perceived threat. It’s constantly worrying about what might happen. For example, you may worry that you may lose your breath. Sometimes it may involve worrying about things that happened in the past. For example, you may have feelings of regret that you smoked cigarettes. In either case, anxiety often goes undiagnosed. Still, people with COPD are twice as likely to experience feelings of anxiety compared with people without COPD.
Not everyone will experience all of these symptoms. Plus, these symptoms may be experienced differently from one person to the next. Still, these are the symptoms most commonly experienced by people living with chronic bronchitis.
Treatments For Chronic Bronchitis
Chronic bronchitis is an inflammatory airway disease. It begins as a chronic cough that may progress to chest tightness and shortness of breath. It’s often diagnosed with another disease called emphysema. They are both often looped under the umbrella term COPD. The good news is this progression can be slowed and symptoms relieved with proper treatment. Here are some of the most common treatments for chronic bronchitis.
Lifestyle Canges:Your doctor may suggest you change the way you live. The most common cause of chronic bronchitis is cigarette smoking. So, the most common recommendation is for you to quit smoking if you smoke. Another common cause is inhaling dusts, fumes, or vapors in the air at your work. So, your doctor may suggest making changes there. This may entail wearing masks, transferring to another department, or retiring. Other lifestyle changes may involve paying attention to outdoor air quality and getting your seasonal flu and pneumonia vaccines. It may also entail using inhalers, nebulizers, and oxygen.
Inhalers: Inhalers are nice because they allow you to inhale medicine directly to your airway where it’s needed. They are also small, hand-held, and easily portable. Today there are many inhaler options for treating chronic bronchitis. Some open airways fast to make breathing easier right now. Others reduce inflammation and keep airways open long-term. Some inhalers are taken on an as needed basis. Others are taken every day to prevent and control symptoms.
Nebulizers: Like inhalers, they allow you to inhale medicine directly to your airways where it’s needed. Older nebulizers are connected to table air compressors. Some newer models are smaller, battery operated units that are easily portable. Nebulizers aren’t as convenient as inhalers. But, they allow you to inhale medicine over a period of time. So, they work nice for
many people with chronic bronchitis.
Oxygen: Sometimes COPD may cause oxygen levels to drop. Supplemental oxygen can help keep oxygen levels normal and breathing easy. It can also improve your ability to stay physically active. The combination of these benefits can help you live better and longer. Most people with COPD only need a low flow of oxygen. This can be delivered with a nasal cannula. This is the kind of oxygen delivery device that slips gently into your nostrils and is generally well tolerated by most people. Modern oxygen concentrators are relatively easy to operate, and portable oxygen concentrators make it easy to stay active despite your need for oxygen.
BiPAP: These are machines that use pressures to assist your breathing. They make sure you’re taking deep enough breaths when you inhale. They also help keep your airways open when you exhale. This makes it so the next breath comes in easier. These can help keep your oxygen levels up when you’re sleeping. It also helps to remove the carbon dioxide from your lungs. They also help you sleep better so you feel better during the daytime.
Pulmonary Rehabilitation: These are programs that involve working with specialists. They usually take place in a gym 2-3 days a week for up to 8 weeks. You’ll learn what exercises are best for people with lung diseases. You’ll learn how to gradually build up your endurance so you can stay active despite your diagnosis. These programs also teach you about your disease so you are better equipped to function with chronic bronchitis on a daily basis. You’ll also get to meet others living with it just like you. (8-10)
There are many options available for treating chronic bronchitis. One or a combination of these treatments can help you breathe easier, stay out of the hospital, and live longer. Learning what
treatments work best for you begins by having that discussion with your doctor.
Final Thoughts on Chronic Bronchitis
Chronic bronchitis is progressive disease that gradually progresses over time. The good news is that this progression can be slowed and symptoms minimized. This is best accomplished by seeing a doctor today and getting a proper diagnosis and treatment
Information on this page is for reference and educational purposes only. For more information about chronic bronchitis, talk to your doctor or primary care provider.
Page last updated: November 28, 2018
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