When someone takes a breath through their nose or mouth, the air travels into the larynx. The next step is through the trachea, which carries the air to the left and right bronchus. The bronchi become smaller the closer they get to the lung tissue and are then considered bronchioles. These passageways then evolve into tiny air sacs called alveoli , which is the site of oxygen and carbon dioxide exchange in the respiratory system.
Primary bronchi are located in the upper portion of the lungs, with secondary bronchi near the center of the lungs. Tertiary bronchi are located near the bottom of these organs, just above the bronchioles.
No gas exchanges occur in any of the bronchi. When the bronchi become swollen due to irritants or infection, bronchitis results and makes breathing more difficult. Bronchitis sufferers also tend to have much more mucus and phlegm than someone without inflamed bronchi. The trachea, or windpipe, helps supply air to the lungs by providing a passage way from the mouth. It is about 4 to 5 inches long and 1 inch in….
If a foreign object is accidentally inhaled, it often becomes lodged in one of the bronchi. People who have trouble eating and swallowing—after a stroke, for example—are prone to aspirating food.
In people who are unconscious, such as during surgery that requires general anesthesia , there is a risk the person could vomit and aspirate some of it. This is why people are told to fast prior to surgery. Inhaled substances can then attract bacteria, leading to aspiration pneumonia. In acute bronchitis, a viral infection usually starts in the nose or throat and then affects the cells of the bronchi, causing them to swell.
Common symptoms of bronchitis include a cough that often involves coughing up phlegm, and wheezing. Chronic bronchitis causes inflammation in the bronchioles, causing a heavy buildup of mucus in the lungs that is ongoing versus acute.
Symptoms include a chronic cough and a susceptibility to bacterial infections; eventually, breathing becomes increasingly difficult. Most cases of chronic bronchitis in the United States are causing by long-term cigarette smoking. Long-term exposure to secondhand smoke, air pollution, and chemical fumes can also play a role. Chronic bronchitis is one manifestation of chronic obstructive pulmonary disease. COPD is a serious disease that can lead to lung cancer and is often fatal.
Asthma is an illness characterized by constriction of the bronchi bronchospasm , which in turn interferes with the passage of air from the environment to the alveoli of the lungs. Attacks of asthma are often triggered by allergies, exercise, or irritants.
When the walls of the bronchi become irreversibly scarred, they can thicken, causing mucus to build up and become a breeding ground for bacteria. Over time, there is a decrease in lung function. Bronchiectasis is usually associated with other illnesses, such as COPD, cystic fibrosis, and recurrent cases of pneumonia.
Bronchiolitis is caused by a viral infection, most commonly respiratory syncytial virus RSV. The bronchioles swell and fill with mucus, making breathing difficult. Infants under three months old are the most likely to be affected by this disease. A rare and serious type of bronchiolitis, called bronchiolitis obliterans also known as "popcorn lung" , is a chronic form of the illness that mainly affects adults.
Bronchopulmonary dysplasia BPD can occur in newborns usually those who are premature who are being treated with oxygen or are on a ventilator for another breathing problem. The high amounts of oxygen and pressure used in these therapies can overstretch the alveoli, inflaming and damaging the inside lining of the airways.
A bronchospasm occurs when your airways constrict, or narrow, causing wheezing and difficulty breathing. Bronchospasms are a symptom of many conditions that affect the airways, including asthma, seasonal allergies, and COPD. Bronchogenic carcinoma is an older term for cancers that arise in the bronchi and bronchioles. Now this term is used interchangeably with lung cancer of all types.
This is the type of lung cancer more commonly found in non-smokers, women, and young adults. These lung cancers tend to be aggressive and may not be found until they have already metastasized spread to other parts of the body.
A bronchopleural fistula is an abnormal passageway a sinus tract that develops between the bronchi and the space between the membranes that line the lungs the pleural cavity. It is a serious complication often caused by lung cancer surgery, but may also develop after chemotherapy, radiation, or an infection.
The following common imaging tests are used to diagnose problems that involve the bronchi. A chest X-ray is often the first procedure used to visualize the lungs. X-rays are useful for identifying causes of aspiration, pneumonia, and lung tumors. During a bronchoscopy , a tube called a bronchoscope is inserted through the mouth and into the bronchi. A bronchoscopy may be performed in order to evaluate symptoms such as a persistent cough or coughing up blood, but can also be used to treat some conditions, such as bleeding in the airways, or removal of a foreign body.
An endobronchial ultrasound can look at tissues that are deeper in the lungs past the bronchial walls. When a tumor is located, a needle biopsy may be performed under the guidance of the endobronchial ultrasound, making it possible to obtain tissue from a tumor without the need for an open lung biopsy. Because there are so many different types of conditions and diseases that can affect the bronchi, treatments vary widely, ranging from medications to surgery.
These medications help relax the muscles around the air passages, which makes breathing easier by widening the airway openings. They are a mainstay of asthma treatment, and usually administered via a nebulizer or an inhaler with a spacer. They help reduce swelling in the airways and decrease the amount of mucus that is produced. Like bronchodilators, they can be given via a nebulizer or an inhaler with a spacer. Bronchitis often goes away on its own or can be treated with over-the-counter medications, called expectorants, that loosen mucus.
The left lung is longer and narrower than the right lung. It has an indentation, called the cardiac notch, on its medial surface for the apex of the heart. The left lung has two lobes. Each lung is enclosed by a double-layered serous membrane , called the pleura. The visceral pleura is firmly attached to the surface of the lung.
At the hilum, the visceral pleura is continuous with the parietal pleura that lines the wall of the thorax. The small space between the visceral and parietal pleurae is the pleural cavity. It contains a thin film of serous fluid that is produced by the pleura.
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