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139 Cards in this Set
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alveoli
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* the functioning unit of the respiratory system.
* exchange of gases takes place here * the basic design of the respiratory system is that of a tube with many branches ending in millions of extremely tiny, very thin walled sacs called alveoli * oxygen moves from the alveoli to the capillary blood by diffusion because alveolar air is rich in oxygen it causes movement from the area of high concentration (alveolar air) to the area of low concentration (capillary blood) characteristics: 1. alveoli walls are made up of a single layer of cells (extremely thin walls) and so are the capillary walls wrapped around them. 2. there are millions of alveoli, making an enormous surface; approximately 100 sq. meters where large amounts of oxygen and carbon dioxide can rapidly be exchanged. |
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respiratory system
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* "breath of life"
* the needs to inhale 16 quarts of air to provide the oxygen necessary for you to perform your daily activities * As the air enters your body, it starts its journey down the respiratory tract that will eventually terminate in approximately 250 million air sacs * By the time the blood leaves the lung capillaries to return to the heart, 97% percent of the blood's hemoglobin has united with oxygen * These tiny sacs, or alveoli, are the functioning units of the respiratory system and are responsible for the exchange of oxygen and carbon dioxide in the blood * actively involved in regulating the acid-base balance of the body * By constantly supplying and distributing adequate oxygen and removing carbon dioxide as it forms, the respiratory system helps maintain an environment necessary for homeostasis and conducive to maximum cell efficiency * organs of this system are designed to filter, warm, and humidify the air, making breathing so natural, efficient, and uneventful that we are oblivious to its importance for our survival. organs of the respiratory system are designed to perform two basic functions for the body: 1. air distribution 2. gas exchange divided into two tracts to assist in the descriptions of symptoms: 1. upper respiratory tract 2. lower respiratory tract regulates: 1. transport of gases 2. gas exchange in lungs and tissue 3. pulmonary ventilation contains: * Nose * Pharynx * Larynx * Trachea * Bronchi * Lungs * Alveoli |
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respiratory membrane
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* thin barrier across which gases are exchanged when passing between the alveoli and blood (between the blood in the capillaries and the air in the alveolus)
* separates the air in the alveoli from the blood in surround capillaries * less than 1 micron thick composed of: 1. The alveolar wall 2. Interstitial fluid 3. The wall of a pulmonary capillary |
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lower respiratory tract
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* includes: trachea, bronchial tree, alveoli and lungs
* facilitating the flow of air from the upper respiratory tract to the lungs and alveoli, which allows the exchange of gases between the air and the blood. * the lungs provide pulmonary ventilation with the processes of inspiration and expiration. * organs are located almost entirely within the thorax or chest cavity * From the larynx, air continues down through the first phase of the lower respiratory tract by entering the trachea, also known as the windpipe * the trachea divides into two tubes called bronchi * ie. chest cold, pneumonia |
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diffusion
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* passive transport process responsible for the exchange of gases in the respiratory system
* process of distributing the air close enough to blood for a gas exchange to take place between air and blood. |
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upper respiratory tract
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* includes: nose, pharynx, and larynx
* organs are located outside of the thorax or chest cavity * Air enters the upper respiratory tract through the nose (it passes over and around the nasal conchae where it begins to be filtered, warmed, and humidified) or mouth. It continues to the pharynx, which is divided into three areas - the nasopharynx, oropharynx, and laryngopharynx - and then to the larynx where air flow continues to the lower respiratory tract. * any infection localized in the mucosa of the upper respiratory tract is called an upper respiratory infection (URI) ie. head cold * symptoms of URI include sinuses, nasal cavity, pharynx, and larynx Upper respiratory infections spread easily because, in addition to communicating with the outside environment, the upper respiratory tract communicates with the: * Mucous lining of the sinuses * Eustachian tube in the ear * Middle ear * Lower respiratory tract * other URI disorders: rhinitis, pharyngitis, laryngitis, epiglottitis, croup |
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bronchi or bronchial tubes
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* In the central portion of the chest cavity—the area known as the mediastinum two tubes that carry air into each lung, known as the primary bronchi
* The primary bronchi enter the lung at a region called the hilus. they then branch into smaller secondary bronchi, then into smaller tertiary bronchi and then into smaller tubes known as bronchioles. * the right primary bronchus is more vertical and "in line" than the left which is why objects tend to get stuck on the right side more * four progressively smaller air tubes that connect the trachea and the alveoli are the primary bronchi, secondary bronchi, bronchioles, and alveolar ducts |
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bronchioles
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* inside the lung, smaller bronchial tubes divide into smaller and smaller tubes called bronchioles
* walls only contain smooth muscle * at the end of the bronchiole tubes they divide in to alveolar ducts than to alveolar sacs. * the small air sacs called alveoli that have capillaries surrounding them. and are filled with numerous alveoli (which resemble grape clusters) * regulate the flow of air to the alveoli |
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olfaction or olfactory receptors
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* nerve endings responsible for the sense of smell
* located in the nasal mucosa |
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air flow
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1. nose or oral/nasal cavity
2. nasopharynx 3. oropharynx 4. laryngopharynx 5. larynx 6. trachea 7. bronchi 8. bronchioles 9. alveolar duct 10. alveoli |
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Respiratory Mucosa
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* membrane that lines most of the air distribution tubes in the entire respiratory tract composed of ciliated pseudostratified epithelium
* covered with mucus and lines the tubes of the respiratory tree. * more than 125 ml. are produced daily * Once air enters the respiratory portion of the nasal passages, it flows over the respiratory mucosa, which is composed of pseudostratified ciliated epithelium and rich with goblet cells. Important facts to remember about the respiratory mucosa: 1. Mucus on the surface moistens air entering the respiratory tract. 2. A rich blood supply in the area of the nasal passageways warms the air as it enters the body, which accounts for the fact that a blow to the nose may cause profuse bleeding (epistaxis). 3. The sticky surface prevents inhaled pathogens and foreign bodies from entering the lungs by trapping them in its flypaper-like environment |
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goblet cells
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* specialized epithelial cells that produce mucus
* Mucus, produced by the goblet cells in the sinuses, moistens inhaled air and is continuously being swept into the nose by the ciliated surface of the respiratory |
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pseudostratified ciliated epithelium
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* epithelium that appears to be two cell layers thick. since it isn't , the term pseudostratified or "false layers" is used
* cilia that extend from the cells are capable of moving in unison; this movement provides some protection against entry of pathogens or foreign particles into the lungs. |
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ciliated mucous membrane
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* The majority of the respiratory tract (besides pseudostratified ciliated epithelium with goblet cells.) is lined with a ciliated mucous membrane that extends down to the smaller bronchioles
* The cilia serve as filters for impurities and contaminants and assist the body with removing impurities by "sweeping" them up and out of the respiratory tract |
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surfactant
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* substance inside the alveoli that helps reduce surface tension in the alveoli and prevents them from collapsing as air moves in and out easily during respiration.
* manufactured by type II cells in the walls of the alveoli * development of surfactant doesn't take place until after birth or 40 weeks gestation |
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alveolar wall
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* Surfactant lines the inner alveolar wall, along with a thin layer of watery fluid, which is necessary to keep the alveoli moist and aids with successful diffusion of the gases exchanged during respiration.
* The moisture in the inner alveolar wall also creates a challenge for the alveoli. The water in the fluid exerts surface tension that can cause the alveolar walls to collapse when air leaves the alveoli during expiration. Surfactant prevents this collapse from occurring and allows the alveoli to inflate with ease after expiration. * walls of the alveoli are thin and close to each other so that air easily flows, or diffuses, back and forth through them * Gas exchange occurs when oxygen from the alveoli diffuses into the bloodstream and carbon dioxide diffuses out of the bloodstream and into the alveoli. Carbon dioxide is then removed from the body when we exhale. |
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surface tension
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* a tendency of a liquid to minimize the area of its surface by contracting
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infant respiratory distress syndrome or IRDS
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* the result of the inability to produce (or absence) surfactant in the alveolar air sacs in a premature infant
* very serious, life-threatening condition that often affects premature infants born of less than 37 weeks gestation or who weigh less than 2.2 kg (5 lbs) at birth * leading cause of death among premature infants in the US, killing more than 5000 babies a year. * affects 50,000 babies annually |
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mucus blanket
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* layer of protective mucus that covers nearly the entire ciliated pseudo-stratified epithelial lining of the air distribution tubes in the respiratory tree.
* the most important air purification mechanism. * air is purified with contaminants such as dust, pollen and smoke particles stick to the mucus and become trapped * only vocal cords, which are covered by stratified squamous epithelium are free of the mucous coating |
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smokers cough
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* results from cigarette smoke irritants that increase production of mucus and paralyze cilia, thus causing accumulations of contaminated mucus to build up and remain in the respiratory passageways for longer periods of time.
* smokers cough is the body's effort to clear the secretions. |
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oropharynx
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* second division and portion of the pharynx located behind the mouth and is the location of the palatine tonsils, commonly known simply as tonsils
* These too are made up of protective lymphatic tissue. |
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epiglottis
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* cartilage that partially covers the opening of the larynx
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larynx
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* voice box
* Located just beneath the pharynx * It is composed of several pieces of cartilage, including the Adam's apple (the largest cartilage in the larynx), which is actually the thyroid cartilage and held together with muscles and ligaments * Also located in the larynx are the glottis and the epiglottis. * forms part of the vital airway to the lungs * it is lined with ciliated mucous membrane, which helps to warm, humidify and filter incoming air. 8 risk of laryngeal cancer increases with smoking and alcohol abuse and occurs most often in men over age 50 and is often diagnosed because of persistent hoarseness and difficulty swallowing. * treatments: surgery, radiation, and chemotherapy. about 1/3 or one third will die from the disease. if surgery is the option the patient must learn esophageal speech or use an electric artificial voice box to speak. |
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pharynx
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* From the nasal cavity, air passes into the pharynx, also called the throat.
* its about 12.5 cm (5 inches) long * serves as a passageway for food and air on its way to the lungs and stomach and is subdivided into three sections: 1. nasopharynx 2. oropharynx 3. laryngopharynx * air enters the pharynx from the two nasal cavities and leaves it by the larynx * food enters from the mouth and leaves by the esophagus |
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laryngopharynx
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* third division and lowest portion of the pharynx
* opens into the larynx and the esophagus, an organ of the digestive system. |
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nasopharynx
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* first division and upper portion of the pharynx located behind (posterior to) the nasal cavities
* Contained within the nasopharynx are the adenoids, or pharyngeal tonsils (made up of lymphatic tissue), and the opening of the eustachian tubes. * middle ear infections can develop from inflammation of the nasopharynx. |
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nose
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* consists of two external nares, or nostrils, provides an entrance to the respiratory passageway through which air travels to and from the lungs
The nose is composed of: * An exterior portion, which is formed by two nasal bones and cartilage * The interior, or nasal cavity, which lies over the roof of the mouth |
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nasal cavity
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* the interior portion of the nose
* is separated by a partition called the septum, which divides the cavity into right and left sides * Each cavity is further divided into three passageways, collectively called conchae or turbinates |
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nasal conchae or turbinates
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* three shelflike structures that protrude into the nasal cavity and increase the surface over which air must flow as it passes through the nasal cavity on each side.
* the mucosa-covered conchae provide greater surface area to slow the passage of air so it has more time to be warmed, humidified and moistened. * this is why breathing through the nose is more humidifying than breathing through your mouth. |
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Paranasal Sinuses
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* Four paranasal sinuses, the frontal, maxillary, sphenoidal, and ethmoidal, are lined with respiratory mucosa and drain into the nasal cavities.
* serve as resonant chambers that enhance the production of sound * help lighten the skull bones * lined with a mucous membrane that assists in the production of mucus for the respiratory tract. * air-filled cavities in the bones around the nose |
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lacrimal sacs
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* two ducts that collect tears from the corner of each eyelid and drain them into the nasal cavity
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external nares
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* where air enters the respiratory tract through (nostrils), then flows into the right and left nasal cavities which are lined by respiratory mucus
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nasal septum
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* a partition that separates the two nasal cavities
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nasal polyps
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* painless, noncancerous tissue growths that may project from the nasal mucosa.
* frequently associated with chronic hay fever. * over time they may grow in size, partially obstruct the nasal passage, and impair breathing. * treatment is surgery if severe |
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sinusitis
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* sinus infections that often develop from colds in which the nasal mucosa is inflamed.
* symptoms include pressure, pain, headache, and often external tenderness, swelling and redness. * in chronic cases infection may spread to adjacent bone or into the cranial cavity inflaming meninges or brain tissue. * treatment: decongestants, analgesics, antibiotics, and in some cases surgery to improve drainage. |
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eustachian tubes or auditory tubes
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* tubes extending from inside the ear to the throat to equalize air pressure between the middle ear and the exterior ear.
* open into the nasopharynx and connect the middle ears with the nasopharynx. |
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esophagus
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* the muscular, mucus-lined tube that connects the pharynx with the stomach
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glottis
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* the space or opening between the vocal cords
* when the muscles of the pharynx, jaws, and tongue modify the opening of the glottis, this results in the various sounds or words. * air expired through the glottis is what causes the vocal cords to vibrate |
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epiglottis
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* cartilage that partially covers the opening of the larynx
* when you swallow the epiglottis; a small leaf-shaped cartilage, covers and protects the opening into the larynx and prevents food and water from entering the glottis during swallowing (or aspiration of food) |
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vocal cords
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* two short fibrous bands that stretch across the interior of the larynx
* located inside the larynx are two pairs of folds, or ligaments covered in mucous membrane that extend inward from the walls of the larynx and stretch across it in a horizontal direction. * the upper pair are know as the vestibular folds or "false vocal cords" they do not play a role in sound or vocalization * the lower pair of vocal cords are known as the "true vocal cords" as air flows from the lungs through the glottis during exhalation, it causes the "true vocal cords" to vibrate, producing sound. * when you talk the opening into the larynx is open to allow the vocal cords to vibrate and produce sounds. * the volume of sounds is dependent on the force with which the air moves past the true vocal cords. * muscles pull on these cords; when they are tense the voice is high pitched; when they are relaxed the voice is low pitched. |
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palatine tonsils
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* masses of lymphatic tissue in the oropharynx (part of the pharynx) located on each side of the throat.
* tonsils most commonly removed in a tonsillectomy, some times adenoids are also removed. * the number of tonsillectomies has been greatly reduced over the last few decades because of the realization that the lymphatic tissue is needed in the body. |
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adenoids
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* collections of lymphatic tissue in the nasopharynx
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Disorders of the Upper Respiratory Tract
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* occur several times a year in most people
* have a tendency to spread. ie. cold becomes sinusitis or otitis media. Disorders of the upper respiratory tract can be classified into one of two conditions: 1. Upper respiratory infections, which are caused by viral or bacterial invasion of the mucosa 2. disorders, which are alterations or injuries to a respiratory system structure * Because the respiratory tract communicates with our external environment, it is particularly vulnerable to infections caused by organisms that populate the air we breathe. * Internal protective mechanisms, such as the mucous membrane, and assistance from other body systems prevent development of more diseases and disorders in this highly susceptible region of the body. * Because the respiratory tract is dark and moist, it is a perfect breeding ground for organisms to multiply. In addition, the respiratory tract is exposed constantly to the outside environment, so it is particularly vulnerable to infection * Injury to the nose occurs relatively frequently because the nose projects from the front of the head. The potential for infection and injury should remind us to be vigilant about exposure and trauma to the upper respiratory system. * In infectious pharyngitis, viruses or bacteria may invade the pharyngeal mucosa directly, causing a local inflammatory response and symptoms of sore throat. Pharyngitis may also be caused by nasal secretions from an infection in another area of the respiratory tract. ie. rhinitis, pharyngitis, laryngitis, epiglottitis, croup |
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endotracheal intubation
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* a tube is placed through the mouth, pharynx, and larynx into the trachea before patients leave the operating room, especially if they have been given a muscle relaxant.
* ensures an open airway |
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tracheostomy
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* procedure that involves the cutting of an opening into the trachea.
* done for a suction devices to remove excess fluid or so a IPPB machine can be used to improve ventilation of the lungs. |
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rhinitis
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* inflammation and swelling of the nasal mucosa
* symptoms: red, itchy, runny nose and partially obstructed breathing * cause - most are viruses (ie. rhinovirus) causing the common cold or flu, or nasal irritants or allergies. * treatment: none for most cases within 7 - 10 days |
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pharyngitis
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* inflammation or infection of the pharynx; or sore throat
* symptoms: pain, redness, and difficulty in swallowing * cause: by any of several pathogens, including the streptococcal bacteria that causes "strep throat" |
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laryngitis
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* inflammation of the mucous lining of the larynx
* inflammation is accompanied by edema of the laryngeal structures * if swelling of the vocal cords occurs, hoarseness or temporary loss of voice results. * cause: bacteria, viruses, exposure to allergens or by overuse of the voice, smoking, and other factors. * even a moderate amount of laryngeal swelling or edema, especially in a young child can obstruct air flow and result in asphyxiation |
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allergic rhinitis
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* or hay fever
* sensitivity-type reactions to many types of nasal irritants and airborne allergens including animal dander and plant pollens (tree, grass or weed) * symptoms: similar to infection rhinitis may become chronic and result in formation of nasal polyps and secondary infections. |
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Epiglottitis
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* non-life-threatening condition caused by It results from an acute obstruction of the larynx that can be caused by an allergen or foreign object, or a Haemophilus influenza type B (Hib) infection, but often is in response to a viral infection
* often struck in children between 3 and 7 years of age a generation ago ( 5 years and younger) * Hib vaccines has dropped occurrence by 99%, very rare now. * Croup is a condition that straddles the line between infection and injury to the upper respiratory tract. |
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croup
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* describes a non-life-threatening type of laryngitis generally seen in children younger than age 3
* cause: by the parainfluenza viruses that obstructs the larynx * symptoms: a harsh bark-like cough and labored inspiration, no fever, and strider during inspiration. * often occurs after going to sleep |
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Anatomical Disorders and Injuries of the upper respiratory tract
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* Anatomical disorders usually involve obstruction or blockage of the nasal cavity resulting from a deviated septum
* Injuries, such as a broken nose, are also common to the upper respiratory tract. * Nasal fractures are the most common fracture of the facial bones; epistaxis and swelling occurs and breathing is often impaired. * If the fracture results in a permanently deviated septum, breathing may be impaired as a result of sinusitis. This is caused by the inability of the sinuses to drain properly into the nasal cavity. |
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deviated septum
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* condition in which the nasal septum shifts from the midline of the nasal cavity.
* If a fracture results in a permanently deviated septum, breathing may be impaired as a result of sinusitis. This is caused by the inability of the sinuses to drain properly into the nasal cavity. * most often occurs from trauma * some people are born with a congenital defect of the septum that results in blockage to one or both sides of the nasal cavity. * no ones nasal septum is exactly on the midsagittal plane, but most are close. * treatment: surgery |
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Epistaxis
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* a nosebleed
* cause: severe inflammation, rubbing (as in rhinitis), trauma, brain injury or hypertension * minor injuries can produce a great deal of blood because the rich blood supply close tot he inside surface of the nasal cavity. |
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strider
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* a high-pitched sound that accompanies inspiration and is caused by blocked air passages.
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rhinovirus
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* causes the common cold
* causes 40% of all acute respiratory illnesses |
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pulmonary ventilation or breathing
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* the process that moves air into and out of the lungs
* lungs provide pulmonary ventilation with the processes of inspiration and expiration * The flow of air during inspiration and expiration is caused by the pressure differences between the atmosphere and the gases inside the lungs. Air, like other gases, flows from a region of higher pressure to a region of lower pressure. * Volumes of air exchanged in pulmonary ventilation can be measured with a spirometer * normal breathing occurs at a rate of 12 - 18 breaths per minute has two phases: 1. inspiration 2. expiration |
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spirometer
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* instrument used to measure the amount of air exchanged in breathing
* By indicating the ability of the respiratory system to oxygenate blood effectively, measurements obtained by spirometry are used to screen for disorders of the heart and lungs |
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lower respiratory tract diseases
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* Ailments of the lower respiratory tract are not as common or frequent as those of the upper respiratory tract.
Diseases are usually acute or chronic and are categorized as: * Obstructive disorders * Infections * Restrictive disorders * Malignancies |
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atelectasis
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* incomplete expansion or collapse of a lung for any reason
* can be caused by the pleural space being filled with substances other than fluid which causes increased pressure on the lungs from outside which causes it to collapse. |
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alveolar sacs
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* structures at the end of each alveolar duct; resembles a cluster of grapes
* wall is made up of numerous alveoli which resembles a single grape |
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carbaminohemoglobin
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* compound formed by the union of carbon dioxide and hemoglobin in RBCs
* Most carbon dioxide is carried away from tissues as bicarbonate ions in the blood. * Carbon dioxide may also combine with the hemoglobin in red blood cells to form carbaminohemoglobin before diffusing out of blood into alveolar air. |
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expiration
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* exhalation - a passive process
* moving air out of the lungs * involves relaxation of the diaphragm and the external intercostals. * this decreases thoracic and lung volume, increasing pressure in the lungs, causing air to flow out. * other mechanisms such as the elastic recoil of lung tissue and surface tension within the alveoli assist with exhalation. * when the pressure in the lung is greater than atmospheric pressure |
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alveolar ducts
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* airway that branches from the smallest bronchioles
* microscopic tubes * at the end of these ducts there is an alveolar sac, that the alveoli, which are clusters of millions of minute air sacs, arise * resemble the main stem of a bunch of grapes |
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pleura
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* membrane that lines the inner surface of the rib cage or chest cavity and covers the outer surface of the lungs.
* extensive, thin, moist, slippery membrane * the parietal pleura lines the walls of the thoracic cavity. |
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oxyhemoglobin
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* hemoglobin combined with oxygen in the red blood cells to form oxyhemoglobin so it can be carried to the tissues and used by the body cells
* When oxygen diffuses into the blood, it binds with hemoglobin to form oxyhemoglobin * In tissues that are low in oxygen, oxyhemoglobin dissociates and releases oxygen into the tissue cells. Carbon dioxide diffuses from the tissue cells into the blood. * oxygen is carried in the blood as oxyhemoglobin |
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inspiration
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* inhalation - an active process
* moving air into the lungs * relies on the muscle contractions of the diaphragm and the external intercostal muscles to increase the volume of the thoracic cavity causing it to expand and reduce the air pressure within it, drawing air into the lungs. |
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eupnea
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* normal breathing
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trachea
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* or windpipe
* a cylindrical tube in the neck that measures approximately 5 inches (11 cm) in length, large air tube in the neck * It extends from the larynx and divides into the two main branches of the lower airway that lead into the lungs. * function is to provide part of the open passageway through which air enters the lungs from the environment. * complete tracheal obstruction causes death within minutes * more than 4000 people a year die from choking, and the 5th major cause of accidental deaths in the US. |
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hyaline cartilage
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* C-shaped rings of cartilage known as hyaline cartilage or tracheal rings partially surround the entire length of the trachea (about 15 to 20 rings)
* Without these rings the trachea could easily collapse and shut off the flow of air * The rings are open on the posterior side of the trachea so that the esophagus has room to expand as food moves along its interior to the stomach |
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abdominal thrust maneuver
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* aka Heimlich maneuver
* used to dislodge a substance during choking by doing abdominal thrusts. |
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secondary bronchi
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* walls are kept open by rings of cartilage fro air passage. (hyaline cartilage)
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lungs
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* the main structures of the respiratory system; fairly large organs.
* Together, this pair of highly elastic organs provides an enormous surface area for gas exchange. * They lie within the chest, or thorax, and extend from the collarbone to the diaphragm, which is a primary muscle of respiration. * The lungs are cone-shaped organs that fill the pleural portion of the thoracic cavity * The broad inferior surface of the lung that rests above the diaphragm is known as the base and the upper pointed margin is the apex. * Each lung is divided into lobes by fissures * The left lung is divided into two lobes and the right lung is divided into three lobes * Visceral pleura covers the outer surface of the lungs and fits snugly over them, much like the skin of an apple. * when the lung is collapsed it can't be ventilated making it useless in breathing. The lungs perform two main functions: 1. Air distribution to the alveoli 2. Gas exchange between the air and the blood |
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diaphragm
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* dome-shaped muscle separating the abdominal cavity from the thoracic cavity.
* the flattened muscular sheet (when contracting) that separates the thorax and abdomen and is a major or primary muscle of respiration * moves down toward the abdominal cavity when contacting, making it longer from top to bottom * nerve impulses passing through the phrenic nerve stimulate the diaphragm to contract * most important muscle in respiration |
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fissures
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* grooves
* divides each lung into lobes by fissures |
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Visceral pleura
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* the inner layer of pleura that is adjacent to the external lung tissue.
* covers the outer surface of the lungs and fits snugly over them, much like the skin of an apple * the intrapleural space lies between the two pleural membranes. |
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respiratory distress syndrome (RDS)
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* results from the body's relative inability to inflate the alveoli of the lungs normally
* most often caused by absence or impairment of the surfactant in the fluid that lines the alveoli. |
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adult respiratory distress syndrome (ARDS)
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* caused by impairment or removal of surfactant in the alveoli
* ie. accidental inhalation of foreign substances such as water, vomit, smoke, or chemical fumes can cause ARDS * edema of the alveolar tissue can impair surfactant and reduce the alveoli's ability to stretch causing respiratory distress. |
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pleurisy
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* an inflammation of the parietal pleura
* symptoms: difficulty in breathing and stabbing pain * discomfort is caused by the constant rubbing back and forth of the visceral and parietal pleurae during breathing * cause: tumors, infections (such as pneumonia and tuberculosis) and other factors. |
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pneumothorax
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* "air in the thorax"
* presence of air in the pleural space on one side of the chest causes: can be a puncture wound to the chest wall or a rupture of the visceral pleura * potentially life threatening |
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hemothorax
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* the presence of blood in the pleural space
* potentially life threatening |
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respiration
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* exchange of gases (oxygen and carbon dioxide) between a living organism and its environment.
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internal respiration
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* the exchange of gases occurs between the blood and the cells of the body
* oxygen diffuses from the blood into the tissue cells, and carbon dioxide diffuses from the tissue cells into the blood * oxyhemoglobin breaks down and hemoglobin remains in the red blood cells. oxygen molecules move rapidly out of the blood through the tissue capillary membrane into the interstitial fluid and into the cells that comprise the tissues. |
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external respiration
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* the exchange of gases between air in the lungs and in the blood.
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cellular respiration
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* refers to the actual use of oxygen by cells in the process of metabolism
* Cellular respiration is the process of oxidizing food molecules, like glucose, to carbon dioxide and water. * The energy released is trapped in the form of adenosine triphosphate (ATP) and is used by all of the energy-consuming activities of the cell. |
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inspiratory muscles
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* muscles that increase the volume of the thorax
* include: the diaphragm and the external intercostals |
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external intercostal muscles
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* located between the ribs
* when they contract they enlarge the size of the thorax by increasing the size of the cavity from front to back and from side to side |
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pressure gradient
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* the main factor that determines the flow of air into or out of the lungs
* diffusion of gases from an area of higher to lower pressure is known as the pressure gradient |
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Respiratory volume
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* Respiratory volumes provide valuable information regarding the physical condition of our lungs.
* measured by a spirometer * Age, sex, body build, weight, physical condition, and disease are all factors that can influence the range of the 500 ml of air that normally moves into and out of the lungs with each breath |
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expiratory reserve volume (ERV)
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* the amount of air that can be forcibly exhaled after expiring the tidal volume
ie. during forceful breathing (like after heavy exercise) an extra 1,000 ml can be expired |
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inspiratory reserve volume (IRV)
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* the amount of air that can be forcibly inspired over and above a normal inspiration
ie. during forceful breathing (like after heavy exercise) an extra 3,300 ml can be inspired |
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vital capacity
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* the largest volume of air that can be moved in and out during one expiration (ventilation)
* refers to the amount of air maximally exhaled following maximal inhalation? * about 4800 ml for normal adults * frequently monitored in patients with lung or heart disease * Vital capacity = Tidal volume + inspiratory reserve volume + expiratory reserve volume |
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tidal volume
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* during normal, quiet breathing, about 500 ml (a pint) of air is moved into and out of the respiratory tract, this is called the tidal volume
* frequently monitored in patients with lung or heart disease * as tidal volume increases, the ERV and IRV decrease |
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residual volume
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* air that remains in the respiratory tract (lungs) after the most forceful expiration
* the volume included in total lung capacity, but not vital capacity |
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expiratory muscles
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* internal intercostals and abdominal muscles contract
* needed sometimes when we speak, sing, or do heavy work * they pull the rib cage inward and decrease the front-to-back size of the thorax * contraction of the muscles pushes the abdominal organs against the underside of the diaphragm pushing it farther upward into the thoracic cavity |
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transportation of carbon dioxide
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* more than 50 mmHg in venous blood can become toxic
transported in the blood to the lungs 3 ways: 1. as dissolved carbon dioxide in plasma (CO2) - 10% 2. as carbaminohemoglobin - 20% 3. as bicarbonate ions (HCO3-) - 70% |
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hypoxia
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* an insufficient oxygen supply to the tissues
ie. patients with emphysema may require supplemental oxygen in order to maintain a normal lifestyle. |
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respiratory control centers
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* where nerve impulses stimulate the muscles of respiration
* located in the brainstem which is in the medulla oblongata * influenced by information received from: 1. chemoreceptors located in the carotid and aortic bodies. 2. Stretch receptors in the lungs and thorax also can alter breathing patterns under special circumstances |
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diffusion
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* passive transport process responsible for the exchange of gases that occurs in the respiratory system.
* the movement of dissolved particles from an area of higher concentration to lower concentration |
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pulmonary artery
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* carries blood that is low in oxygen content because it is blood that has been returned to the heart from the body.
* it will pick up oxygen as it travels through the lungs before being returned to the heart via the pulmonary veins. |
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osmosis
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* the movement of fluid through a semipermeable membrane
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chemoreceptors
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* receptors that respond to chemical changes in the body
* when stimulated by increasing levels of blood carbon dioxide and decreases in blood oxygen level. * chemoreceptors can send nerve impulses to the respiratory regulatory centers that can modify respiratory rates. * Specialized chemoreceptors in the walls of the aorta and carotid arteries are sensitive to changes in arterial carbon dioxide concentration two chemoreceptors are located in the: 1. carotid bodies 2. aortic bodies |
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carotid
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* chemoreceptors located in the carotid artery that detect changes in oxygen, carbon dioxide, and blood acid levels.
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aortic bodies
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* specialized receptors that are sensitive to increases in blood carbon dioxide levels and decreases in blood oxygen levels
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Stretch receptors
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* specialized sensory nerve endings in muscles that are stimulated by stretch movements.
* pulmonary stretch receptors influence the normal pattern of breathing and protect the respiratory system from excess stretching caused by harmful overinflation. * sensory receptors that help keep the lung from overexpanding. located in: 1. airways 2. alveoli |
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cerebral cortex
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* can influence respiration by modifying the rate at which neurons "fire" in the inspiratory and expiratory centers of the medulla
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types of breathing
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* The rate and depth of respirations can vary considerably. Exercise, emotions, and disease pathology are just a few examples of conditions that can alter normal breathing.
* involuntarily, Breathing rates are normally determined involuntarily by the nervous system to ensure homeostasis * Temporary variations in breathing are directed by the nervous system to accommodate the cells' need for oxygen and removal of waste during periods of stress. |
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Eupnea
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* a type of breathing pattern
* normal respiratory rate * the individual is usually not aware of the breathing pattern |
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hyperventilation
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* a type of breathing pattern
* very rapid and deep respirations * sometimes results from a conscious voluntary effort proceeding exertion or from psychological factors * characterized by low levels of carbon dioxide |
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hypoventilation
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* a type of breathing pattern
* slow and shallow respirations * characterized by high levels of carbon dioxide |
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dyspnea
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* labored or difficult breathing
* a type of breathing pattern |
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orthopnea
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* dyspnea that is relieved by moving into an upright or sitting position
* a type of breathing pattern |
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apnea
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* when breathing stops completely for a brief period, regardless of cause
* a type of breathing pattern |
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cheyne-stokes respiration (CSR)
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* a series of cycles of alternating apnea and hyperventilation
* a type of breathing pattern * occurs in critical diseases |
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respiratory arrest
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* failure to resume breathing after a period of apnea
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Obstructive Disorders (pulmonary disease)
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* Chronic obstructive pulmonary disease comprises a group of common respiratory diseases that are characterized by the presence of persistent airflow limitation
* a progressive, irreversible obstruction of air flow that may result from a variety of preexisting obstructive disorders. * Long-term tobacco smoking is the usual causative agent. * This common and often avoidable disease affects at least 6% of men and 3% of women and is the fourth most common cause of death in the United States today * It is the only common cause of death continuing to increase in prevalence. 1. Inflammation of the airways leads to coughing, chronic mucus production, airway mucosal swelling, and airway narrowing. 2. Destruction of functioning lung tissue and the loss of respiratory membrane result in impaired gas exchange and oxygen hunger. 3. narrowing occurs and leads to hyperinflation, which flattens the diaphragm, placing the respiratory muscles at a mechanical disadvantage Some examples of chronic obstructive pulmonary disease include: 1. Chronic bronchitis 2. Emphysema 3. Asthma |
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Chronic bronchitis
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* an obstructive Disorders (pulmonary disease)
* Air tubes narrow as a result of swollen tissues and excessive mucus production in chronic bronchitis. |
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Emphysema
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* an obstructive Disorders (pulmonary disease)
* Walls of alveoli are torn and cannot be repaired in emphysema. Alveoli fuse into large air spaces. * a condition in which air becomes trapped within alveoli and causes them to enlarge and rupture - the rupture leads to hypoxia. |
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Asthma
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* an obstructive Disorders (pulmonary disease)
* Edema of respiratory mucosa and excessive mucus production obstruct airways in asthma. * symptoms: recurring spasms of the walls of the bronchial passages, and rupture of the alveoli is not a primary symptom |
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lower respiratory tract infections
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* Bacteria are the dominant pathogens, but viruses, fungi, and many other pathogens can also cause lower respiratory tract infections.
Some examples of lower respiratory infections include: 1. Acute bronchitis 2. Bronchiolitis 3. Pneumonia * These disorders, especially pneumonia, can be severe or fatal. |
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Acute bronchitis
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* a lower respiratory tract infection
* Inflammation of bronchi that usually progresses to a deep cough producing sputum that contains mucus and pus. |
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Bronchiolitis
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* a lower respiratory tract infection
* Inflammation of the bronchioles that usually involves respiratory distress such as expiratory wheezing. |
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Pneumonia
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* a lower respiratory tract infection
* acute Inflammation of the lungs in which the alveoli and bronchi become plugged with thick exudate (fluid). * pneumonia, can be severe or fatal * Of the lower respiratory infections, pneumonia remains the most common infection seen in the community and among hospitalized patients. In spite of the use of antibiotics, the mortality associated with pneumonia is quite high. |
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Restrictive Disorders (lower respiratory tract)
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* a decrease in lung capacities results from the inability of the lungs to expand and relax as adequately, rapidly, and completely as the diaphragm and intercostal muscles demand
* The vital capacity and the residual volume are reduced, yet the flow of air is normal. * result from either an alteration in the lung tissue or conditions external to the lung tissue. * Damage to lung tissue may result in a loss of elasticity. * In some restrictive disorders, the tissues that exchange gas may thicken. As a result, arterial oxygen levels may decrease. Some examples of restrictive disorders include: 1. Pulmonary fibrosis 2. Thoracic tumors 3. Obesity 4. Accumulation of fluids around the lungs |
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Pulmonary fibrosis
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* a restrictive disorder (lower respiratory tract)
* The formation of fibrous connective tissue in the lung caused by this disorder will alter lung tissue. |
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Thoracic tumors
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* a restrictive disorder (lower respiratory tract)
* Thoracic tumors can restrict the capacity of the lungs to expand and/or relax. |
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Obesity
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* a restrictive disorder (lower respiratory tract)
* Obesity can restrict the capacity of the lungs to expand and/or relax |
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Accumulation of fluids around the lungs
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* a restrictive disorder (lower respiratory tract)
* Accumulation of fluids around the lungs can restrict the capacity of the lungs to expand and/or relax. |
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Lung disorders
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* Lung disorders are among the most common conditions affecting humans
* Genetic, environmental, and behavioral factors all play a role in a person's susceptibility to and risk of lung disease. |
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lung cancer
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* Malignancy (lower respiratory tract) disease of pulmonary tissue
* though largely preventable, claims the lives of at least 150,000 people in the United States each year. * Approximately 87 percent of victims develop lung cancer from smoking or exposure to secondhand smoke. * The remainder of victims—nearly 19,500 people—develop lung cancer resulting from exposure to dangerous substances such as asbestos, silica dust, radon, and environmental pollutants. Lung cancer symptoms include: * Persistent or worsening cough * Extreme exhaustion * Continual chest pains treatment: Surgery, such as a lobectomy or pneumonectomy, and chemotherapy are the current strategies being used to treat lung cancer. |
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lobectomy
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* removal of the lobe of a lung
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pneumonectomy
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* removal of a lung
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chemotherapy
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* the treatment of diseases with chemical agents
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tuberculosis
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* a chronic bacillus infection that usually affects the lung, caused by Mycobacterium tuberculosis
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chronic obstructive pulmonary disease (COPD)
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* a broad term used to describe conditions of progressive irreversible obstruction of expiratory air flow
* have difficulty emptying their lungs and have visibly hyperinflated chests |
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mediastinum
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* the space between the lungs occupied by the esophagus, trachea, large blood vessels, and the heart
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Standard atmospheric pressure
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* 760 mm Hg
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Boyle's law
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* states that the volume of a gas varies inversely with pressure at a constant temperature
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medulla
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* basic respiratory rhythm centers are located in the medulla part of the brain.
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