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Bronchial Tree: Anatomy

Bronchial Tree: Anatomy

The collective term “bronchial tree” refers to the bronchi and all of their subsequent branches. The bronchi are the airways of the lower respiratory tract. At the level of the 3rd or 4th thoracic vertebra, the trachea Trachea The trachea is a tubular structure that forms part of the lower respiratory tract. The trachea is continuous superiorly with the larynx and inferiorly becomes the bronchial tree within the lungs. The trachea consists of a support frame of semicircular, or C-shaped, rings made out of hyaline cartilage and reinforced by collagenous connective tissue. Trachea: Anatomy bifurcates into the left and right main bronchi. The right main bronchus is shorter and more vertical in direction than the left. Both of these bronchi continue to divide into secondary or lobar bronchi that bifurcate further and further in order to sufficiently spread the respiratory air completely into the left and right pulmonary lobes. The terminal segment of each bronchus contains millions of alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS), the site of gas exchange Gas exchange Human cells are primarily reliant on aerobic metabolism. The respiratory system is involved in pulmonary ventilation and external respiration, while the circulatory system is responsible for transport and internal respiration. Pulmonary ventilation (breathing) represents movement of air into and out of the lungs. External respiration, or gas exchange, is represented by the O2 and CO2 exchange between the lungs and the blood. Gas Exchange.

Last updated: 9 Mar, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Contents

Development

The development of the tracheobronchial tree and lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy occurs in 5 stages. The tracheobronchial tree and lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy originate from the foregut Foregut Development of the Abdominal Organs of the embryonic gut tube, beginning at week 4 of gestation and ending in childhood.

Table: Development of the tracheobronchial tree and lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy and clinical relevance
Stage Description Clinical relevance
Embryonic period
  • Occurs during weeks 4–7
  • Respiratory diverticulum Diverticulum A pouch or sac opening from the colon. Diverticular Disease buds off the foregut Foregut Development of the Abdominal Organs.
  • Tracheoesophageal groove Tracheoesophageal groove Development of the Respiratory System “pinches off” the bud → trachea Trachea The trachea is a tubular structure that forms part of the lower respiratory tract. The trachea is continuous superiorly with the larynx and inferiorly becomes the bronchial tree within the lungs. The trachea consists of a support frame of semicircular, or C-shaped, rings made out of hyaline cartilage and reinforced by collagenous connective tissue. Trachea: Anatomy and esophagus Esophagus The esophagus is a muscular tube-shaped organ of around 25 centimeters in length that connects the pharynx to the stomach. The organ extends from approximately the 6th cervical vertebra to the 11th thoracic vertebra and can be divided grossly into 3 parts: the cervical part, the thoracic part, and the abdominal part. Esophagus: Anatomy
  • Trachea Trachea The trachea is a tubular structure that forms part of the lower respiratory tract. The trachea is continuous superiorly with the larynx and inferiorly becomes the bronchial tree within the lungs. The trachea consists of a support frame of semicircular, or C-shaped, rings made out of hyaline cartilage and reinforced by collagenous connective tissue. Trachea: Anatomy bifurcates into right and left bronchial buds.
 Defects:
Pseudoglandular period
  • Occurs during weeks 5–16
  • Bronchial buds → secondary buds → tertiary buds
  • Continued branching → terminal bronchioles
  • Mesoderm Mesoderm The middle germ layer of an embryo derived from three paired mesenchymal aggregates along the neural tube. Gastrulation and Neurulation → pulmonary vasculature/ capillaries Capillaries Capillaries are the primary structures in the circulatory system that allow the exchange of gas, nutrients, and other materials between the blood and the extracellular fluid (ECF). Capillaries are the smallest of the blood vessels. Because a capillary diameter is so small, only 1 RBC may pass through at a time. Capillaries: Histology
  • Development of type II pneumocyte precursors → produce amniotic fluid Amniotic fluid A clear, yellowish liquid that envelopes the fetus inside the sac of amnion. In the first trimester, it is likely a transudate of maternal or fetal plasma. In the second trimester, amniotic fluid derives primarily from fetal lung and kidney. Cells or substances in this fluid can be removed for prenatal diagnostic tests (amniocentesis). Placenta, Umbilical Cord, and Amniotic Cavity
  • Defects:
  • Lung tissue is incapable of gas exchange Gas exchange Human cells are primarily reliant on aerobic metabolism. The respiratory system is involved in pulmonary ventilation and external respiration, while the circulatory system is responsible for transport and internal respiration. Pulmonary ventilation (breathing) represents movement of air into and out of the lungs. External respiration, or gas exchange, is represented by the O2 and CO2 exchange between the lungs and the blood. Gas Exchange at this stage.
  • Infants born at this stage cannot survive.
Canalicular period
  • Occurs during weeks 16–26
  • Terminal bronchioles → respiratory bronchioles → alveolar ducts → primitive alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS)
  • Prominent lung capillaries Capillaries Capillaries are the primary structures in the circulatory system that allow the exchange of gas, nutrients, and other materials between the blood and the extracellular fluid (ECF). Capillaries are the smallest of the blood vessels. Because a capillary diameter is so small, only 1 RBC may pass through at a time. Capillaries: Histology
  • Surfactant Surfactant Substances and drugs that lower the surface tension of the mucoid layer lining the pulmonary alveoli. Acute Respiratory Distress Syndrome (ARDS) production
  • Airway Airway ABCDE Assessment diameter ↑
  • Defects:
  • Respiration Respiration The act of breathing with the lungs, consisting of inhalation, or the taking into the lungs of the ambient air, and of exhalation, or the expelling of the modified air which contains more carbon dioxide than the air taken in. Nose and Nasal Cavity: Anatomy is possible at 24 weeks.
  • Infants born at the end of this stage can survive with intensive care.
Saccular period
  • Occurs during weeks 26–birth
  • Alveolar ducts → terminal sacs
  • Gas-exchange surface area of the lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy expands.
  • Surfactant Surfactant Substances and drugs that lower the surface tension of the mucoid layer lining the pulmonary alveoli. Acute Respiratory Distress Syndrome (ARDS) production increases.
  • Blood–air barrier fully develops ( type I pneumocytes Type I pneumocytes Lungs: Anatomy).
 Infants born ≥ 32 weeks have a higher survival rate.
Alveolar period
  • Occurs during from 32 weeks’ gestation to 8 years of life
  • Mature type II pneumocytes Type II pneumocytes Lungs: Anatomy
  • Terminal sacs septate → alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS)
  • Following birth, alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS) ↑ in number:
    • At birth: 50 million
    • By age 8 years: 300 million
  • In utero: ↑ Vascular resistance Resistance Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow. Ventilation: Mechanics of Breathing due to aspiration of amniotic fluid Amniotic fluid A clear, yellowish liquid that envelopes the fetus inside the sac of amnion. In the first trimester, it is likely a transudate of maternal or fetal plasma. In the second trimester, amniotic fluid derives primarily from fetal lung and kidney. Cells or substances in this fluid can be removed for prenatal diagnostic tests (amniocentesis). Placenta, Umbilical Cord, and Amniotic Cavity
  • Postpartum: Inspiration Inspiration Ventilation: Mechanics of Breathing of air leads to a drop in pulmonary vascular resistance Resistance Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow. Ventilation: Mechanics of Breathing.
  • Embryonic development of the gut tube

    Embryonic development of the gut tube

    Image by Lecturio. License: CC BY-NC-SA 4.0
  • Development of the lungs

    Development of the lungs Lungs Lungs are the main organs of the respiratory system. Lungs are paired viscera located in the thoracic cavity and are composed of spongy tissue. The primary function of the lungs is to oxygenate blood and eliminate CO2. Lungs: Anatomy:
    The respiratory system begins development by week 4 of gestation. The olfactory pit forms from the ectoderm Ectoderm The outer of the three germ layers of an embryo. Gastrulation and Neurulation, one of the structures to become the nasal cavity Nasal cavity The proximal portion of the respiratory passages on either side of the nasal septum. Nasal cavities, extending from the nares to the nasopharynx, are lined with ciliated nasal mucosa. Nose and Nasal Cavity: Anatomy. The laryngotracheal bud forms from the primitive pharynx Pharynx The pharynx is a component of the digestive system that lies posterior to the nasal cavity, oral cavity, and larynx. The pharynx can be divided into the oropharynx, nasopharynx, and laryngopharynx. Pharyngeal muscles play an integral role in vital processes such as breathing, swallowing, and speaking. Pharynx: Anatomy. From this bud, the longitudinal extension Extension Examination of the Upper Limbs becomes the tracheal and bronchial buds.
    The process of elongation Elongation Polymerase Chain Reaction (PCR) and branching of buds continues as conducting airways up to 16 weeks of gestation. Major maturation occurs by 24 weeks, with significant alveolar precursors developing and an increased amount of surfactant Surfactant Substances and drugs that lower the surface tension of the mucoid layer lining the pulmonary alveoli. Acute Respiratory Distress Syndrome (ARDS) produced. By 28 weeks of gestation, there usually will be enough mature alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS).

    Image: “2328 Development of Lower Respiratory SystemN” by OpenStax College. License: CC BY 3.0

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Gross Anatomy

The bronchial tree begins at the bifurcation of the trachea Trachea The trachea is a tubular structure that forms part of the lower respiratory tract. The trachea is continuous superiorly with the larynx and inferiorly becomes the bronchial tree within the lungs. The trachea consists of a support frame of semicircular, or C-shaped, rings made out of hyaline cartilage and reinforced by collagenous connective tissue. Trachea: Anatomy at the carina, approximately at the level of T5. The trachea Trachea The trachea is a tubular structure that forms part of the lower respiratory tract. The trachea is continuous superiorly with the larynx and inferiorly becomes the bronchial tree within the lungs. The trachea consists of a support frame of semicircular, or C-shaped, rings made out of hyaline cartilage and reinforced by collagenous connective tissue. Trachea: Anatomy bifurcates into the main left and right bronchi, These bronchi continue to branch until they form alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS), the site of gas exchange Gas exchange Human cells are primarily reliant on aerobic metabolism. The respiratory system is involved in pulmonary ventilation and external respiration, while the circulatory system is responsible for transport and internal respiration. Pulmonary ventilation (breathing) represents movement of air into and out of the lungs. External respiration, or gas exchange, is represented by the O2 and CO2 exchange between the lungs and the blood. Gas Exchange. Each bronchial segment progressively becomes smaller in diameter and has a thinner wall.

Main branching structure and components

  • Trachea Trachea The trachea is a tubular structure that forms part of the lower respiratory tract. The trachea is continuous superiorly with the larynx and inferiorly becomes the bronchial tree within the lungs. The trachea consists of a support frame of semicircular, or C-shaped, rings made out of hyaline cartilage and reinforced by collagenous connective tissue. Trachea: Anatomy → carina → main bronchi → lobar bronchi → segmental bronchi → terminal bronchioles → respiratory bronchioles → alveolar duct → alveolar sac → alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS)
  • Bronchi:
    • Main bronchi:
      • The left main bronchus is longer than the right and enters the left lung at the level of T6.
      • The right main bronchus is wider, shorter, and more vertical than the left (most frequent pathway for aspirated foreign objects) and enters the right lung at the level of T5.
    • Lobar or secondary bronchi:
      • 2 left lobar bronchi
      • 3 right lobar bronchi
    • Segmental or tertiary bronchi:
      • Each supplies a bronchopulmonary segment, which is the largest subdivision of a lobe.
      • 10 segments in the right lung
      • 8–10 segments in the left lung
  • Conducting bronchioles:
    • 20–25 generations of branching
    • End as terminal bronchioles
    • Lack cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage: Histology, glands, and alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS) (distinguishing feature from bronchi)
  • Terminal bronchioles give rise to several respiratory bronchioles.
  • Respiratory bronchioles:
    • Characterized by the outpocketing from their lumen: alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS)
    • Each respiratory bronchiole gives rise to 2–11 alveolar ducts.
    • Each alveolar duct gives rise to 5–6 alveolar sacs, the site of gas exchange Gas exchange Human cells are primarily reliant on aerobic metabolism. The respiratory system is involved in pulmonary ventilation and external respiration, while the circulatory system is responsible for transport and internal respiration. Pulmonary ventilation (breathing) represents movement of air into and out of the lungs. External respiration, or gas exchange, is represented by the O2 and CO2 exchange between the lungs and the blood. Gas Exchange.
Anterior view of the larynx, trachea, and bronchial tree

Anterior view of the larynx Larynx The larynx, also commonly called the voice box, is a cylindrical space located in the neck at the level of the C3-C6 vertebrae. The major structures forming the framework of the larynx are the thyroid cartilage, cricoid cartilage, and epiglottis. The larynx serves to produce sound (phonation), conducts air to the trachea, and prevents large molecules from reaching the lungs. Larynx: Anatomy, trachea Trachea The trachea is a tubular structure that forms part of the lower respiratory tract. The trachea is continuous superiorly with the larynx and inferiorly becomes the bronchial tree within the lungs. The trachea consists of a support frame of semicircular, or C-shaped, rings made out of hyaline cartilage and reinforced by collagenous connective tissue. Trachea: Anatomy, and bronchial tree:
Note the main divisions of the bronchi.

Image by Lecturio. License: CC BY-NC-SA 4.0

Neurovasculature

Blood supply:

The bronchial tree is supplied by branches of the left and right bronchial arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology.

Venous drainage: 

  • The bronchial veins Veins Veins are tubular collections of cells, which transport deoxygenated blood and waste from the capillary beds back to the heart. Veins are classified into 3 types: small veins/venules, medium veins, and large veins. Each type contains 3 primary layers: tunica intima, tunica media, and tunica adventitia. Veins: Histology are analogous to the bronchial arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology. 
  • The bronchial tree is drained by tributaries of the main left and right bronchial veins Veins Veins are tubular collections of cells, which transport deoxygenated blood and waste from the capillary beds back to the heart. Veins are classified into 3 types: small veins/venules, medium veins, and large veins. Each type contains 3 primary layers: tunica intima, tunica media, and tunica adventitia. Veins: Histology:
    • Left bronchial vein drains into the left superior intercostal vein or the accessory hemiazygos vein.
    • Right bronchial vein drains into the azygos vein.

Innervation:

Innervation is supplied by the pulmonary plexus of the vagus nerve Vagus nerve The 10th cranial nerve. The vagus is a mixed nerve which contains somatic afferents (from skin in back of the ear and the external auditory meatus), visceral afferents (from the pharynx, larynx, thorax, and abdomen), parasympathetic efferents (to the thorax and abdomen), and efferents to striated muscle (of the larynx and pharynx). Pharynx: Anatomy.

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Microscopic Anatomy

  • Bronchi:
    • Mucosa: pseudostratified ciliated columnar epithelium Epithelium The epithelium is a complex of specialized cellular organizations arranged into sheets and lining cavities and covering the surfaces of the body. The cells exhibit polarity, having an apical and a basal pole. Structures important for the epithelial integrity and function involve the basement membrane, the semipermeable sheet on which the cells rest, and interdigitations, as well as cellular junctions. Surface Epithelium: Histology
    • Contains goblet cells Goblet cells A glandular epithelial cell or a unicellular gland. Goblet cells secrete mucus. They are scattered in the epithelial linings of many organs, especially the small intestine and the respiratory tract. Glandular Epithelium: Histology that secrete mucus into the tracheal lumen
    • Submucosa: provides support
    • Smooth muscle
    • Cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage: Histology layer of hyaline cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage: Histology
  • Bronchioles:
    • Ciliated columnar epithelium Epithelium The epithelium is a complex of specialized cellular organizations arranged into sheets and lining cavities and covering the surfaces of the body. The cells exhibit polarity, having an apical and a basal pole. Structures important for the epithelial integrity and function involve the basement membrane, the semipermeable sheet on which the cells rest, and interdigitations, as well as cellular junctions. Surface Epithelium: Histology in larger bronchioles
    • Nonciliated columnar epithelium Epithelium The epithelium is a complex of specialized cellular organizations arranged into sheets and lining cavities and covering the surfaces of the body. The cells exhibit polarity, having an apical and a basal pole. Structures important for the epithelial integrity and function involve the basement membrane, the semipermeable sheet on which the cells rest, and interdigitations, as well as cellular junctions. Surface Epithelium: Histology in smaller bronchioles
    • Does not contain goblet cells Goblet cells A glandular epithelial cell or a unicellular gland. Goblet cells secrete mucus. They are scattered in the epithelial linings of many organs, especially the small intestine and the respiratory tract. Glandular Epithelium: Histology
    • Contains club cells that secrete a component of surfactant Surfactant Substances and drugs that lower the surface tension of the mucoid layer lining the pulmonary alveoli. Acute Respiratory Distress Syndrome (ARDS)
  • Terminal and respiratory bronchioles: 
    • Do not contain glands or cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage: Histology
    • Both present mucosa, submucosa, smooth muscle, and tunica adventitia Tunica adventitia The outermost covering of organs, blood vessels, and other such structures in the body. Arteries: Histology.
    • Terminal bronchiole: ciliated cuboidal epithelium Epithelium The epithelium is a complex of specialized cellular organizations arranged into sheets and lining cavities and covering the surfaces of the body. The cells exhibit polarity, having an apical and a basal pole. Structures important for the epithelial integrity and function involve the basement membrane, the semipermeable sheet on which the cells rest, and interdigitations, as well as cellular junctions. Surface Epithelium: Histology
    • Respiratory bronchiole: simple cuboidal epithelium Simple cuboidal epithelium Surface Epithelium: Histology and club cells
  • Alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS):
    • Hollow sacs that serve as the site of gas exchange Gas exchange Human cells are primarily reliant on aerobic metabolism. The respiratory system is involved in pulmonary ventilation and external respiration, while the circulatory system is responsible for transport and internal respiration. Pulmonary ventilation (breathing) represents movement of air into and out of the lungs. External respiration, or gas exchange, is represented by the O2 and CO2 exchange between the lungs and the blood. Gas Exchange
    • Found in respiratory bronchioles, along the walls ducts, and in the alveolar sacs
    • Separated by interalveolar septa made of elastic Elastic Connective Tissue: Histology fibers and capillaries Capillaries Capillaries are the primary structures in the circulatory system that allow the exchange of gas, nutrients, and other materials between the blood and the extracellular fluid (ECF). Capillaries are the smallest of the blood vessels. Because a capillary diameter is so small, only 1 RBC may pass through at a time. Capillaries: Histology
    • Lined by types I and II pneumocytes
      • Type I: comprise 95% of total alveolar area and form the blood–air barrier
      • Type II: comprise 5% of total alveolar area and secrete surfactant Surfactant Substances and drugs that lower the surface tension of the mucoid layer lining the pulmonary alveoli. Acute Respiratory Distress Syndrome (ARDS)
Conducting and respiratory zone

Microscopic anatomy of the lower respiratory tract

Image by Lecturio. License: CC BY-NC-SA 4.0
  • Cross section of secondary bronchus

    Cross-section of a secondary bronchus

    Image: “Cross-section of secondary bronchus” by Jpogi. License: Public Domain
  • Tertiary bronchus

    Cross-section of a tertiary bronchus

    Image: “Tertiary bronchus” by Jpogi. License: Public Domain
  • Terminal bronchiole

    Cross-section of terminal bronchiole

    Image: “Terminal bronchiole” by Jpogi. License: Public Domain

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Clinical Relevance

The following are conditions that can affect Affect The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves. Psychiatric Assessment the bronchial tree:

  • Asthma Asthma Asthma is a chronic inflammatory respiratory condition characterized by bronchial hyperresponsiveness and airflow obstruction. The disease is believed to result from the complex interaction of host and environmental factors that increase disease predisposition, with inflammation causing symptoms and structural changes. Patients typically present with wheezing, cough, and dyspnea. Asthma: chronic inflammatory disease of the airways: Inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation and bronchial hyperreactivity Bronchial hyperreactivity Tendency of the smooth muscle of the tracheobronchial tree to contract more intensely in response to a given stimulus than it does in the response seen in normal individuals. This condition is present in virtually all symptomatic patients with asthma. The most prominent manifestation of this smooth muscle contraction is a decrease in airway caliber that can be readily measured in the pulmonary function laboratory. Asthma occur. The airways of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with asthma Asthma Asthma is a chronic inflammatory respiratory condition characterized by bronchial hyperresponsiveness and airflow obstruction. The disease is believed to result from the complex interaction of host and environmental factors that increase disease predisposition, with inflammation causing symptoms and structural changes. Patients typically present with wheezing, cough, and dyspnea. Asthma are more sensitive to various stimuli, leading to paroxysmal and recurrent obstruction of the airways.
  • Emphysema Emphysema Enlargement of air spaces distal to the terminal bronchioles where gas-exchange normally takes place. This is usually due to destruction of the alveolar wall. Pulmonary emphysema can be classified by the location and distribution of the lesions. Chronic Obstructive Pulmonary Disease (COPD): condition characterized by dilation of the airways, with decreased elasticity Elasticity Resistance and recovery from distortion of shape. Skeletal Muscle Contraction and increased compliance Compliance Distensibility measure of a chamber such as the lungs (lung compliance) or bladder. Compliance is expressed as a change in volume per unit change in pressure. Veins: Histology, due to alveolar wall destruction: The most common cause of emphysema Emphysema Enlargement of air spaces distal to the terminal bronchioles where gas-exchange normally takes place. This is usually due to destruction of the alveolar wall. Pulmonary emphysema can be classified by the location and distribution of the lesions. Chronic Obstructive Pulmonary Disease (COPD) is smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases. Alpha-1-antitrypsin deficiency may also result in the development of emphysema Emphysema Enlargement of air spaces distal to the terminal bronchioles where gas-exchange normally takes place. This is usually due to destruction of the alveolar wall. Pulmonary emphysema can be classified by the location and distribution of the lesions. Chronic Obstructive Pulmonary Disease (COPD).
  • Bronchiectasis Bronchiectasis Bronchiectasis is a chronic disease of the airways that results from permanent bronchial distortion. This results from a continuous cycle of inflammation, bronchial damage and dilation, impaired clearance of secretions, and recurrent infections. Bronchiectasis: disease in which there is permanent enlargement of parts of the airways. In this condition, damage to the airways causes them to widen and become flabby and scarred. Usually, the disorder occurs as the result of preexisting lung disease.

References

  1. Moore, K. L., et al. (2017). Clinically Oriented Anatomy. Lippincott Williams & Wilkins.
  2. Drake, R., et al. Gray’s Anatomy for Students E-Book. Elsevier Health Sciences, 2014.
  3. Standring, S. Gray’s Anatomy: The Anatomical Basis of Clinical Practice, 41st ed. Edinburgh: Churchill Livingstone/Elsevier, 2016.
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