Term
|
Definition
|
|
Term
| When does the respiratory system begin to develop? |
|
Definition
|
|
Term
| What structures are part of the conducting zone? |
|
Definition
| nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles |
|
|
Term
| What structures are part of the respiratory zone? |
|
Definition
| respiratory bronchioles, alveolar ducts, alveolar sacs and the alveoli |
|
|
Term
| What structures are cephalic to the larynx? |
|
Definition
| nasal and oral cavities, pharynx |
|
|
Term
| The formation of the lung bud is caused by what process? |
|
Definition
| lateral folding of two sphlanchnic mesoderm and endoderm that meed at midline to separate the larynx and trachea from the esophagus |
|
|
Term
| The larynx is first seen as what structure? |
|
Definition
| ventral outgrowth of endoderm from the foregut --> lung bud/respiratory diverticulum |
|
|
Term
| The larynx arises from what early embryology tissues? |
|
Definition
1. epithelium: endoderm
2. muscles and cartilage: neural crest cells |
|
|
Term
| The trachea develops from what tissues? |
|
Definition
1. epithelium: endoderm
2. muscles/cartilage comes from splanchnic mesoderm |
|
|
Term
| At the end of lung development in early childhood, how many divisions have the bronchi undergone? |
|
Definition
| 24 generations of branching |
|
|
Term
| List, in order of earliest to latest in development, the branching of the trachea to form bronchioles. |
|
Definition
| Trachea --> L/R bronchi --> R bronchus gives off 3 diverticula and L bronchus gives off two diverticula ---> lobular bronchi --> smaller bronchi ---> bronchioles |
|
|
Term
| At birth in a term baby, how many generations of branching has occurred? |
|
Definition
| more than 17, but less than 24 |
|
|
Term
| Name the 4 stages of development for the lungs |
|
Definition
| Pseudoglangular, canclicular, terminal sac, and aveolar period |
|
|
Term
| What happens during the pseudoglandular period? |
|
Definition
-bronchi are dividing into bronchioles. Typically from week 5th-28th week
-trachea and foregut separate |
|
|
Term
| What is the canalicular period |
|
Definition
-formation of respiratory bronchioles (which will give rise to alveolar ducts)
-Epithelium is cuboidal
-capillaries proliferate but do not reach the respiratory Epithelium
-starting at 5th month - type II alvelolar epithelial cells develop |
|
|
Term
| Describe the events of the terminal sac phase of lung development |
|
Definition
-starts at wk 26 - birth
-capillaries proliferate and begin to reach respiratory epithelium
-epithelium becomes squamous epithelium made of type I alveolar epithelial cells
-starting at 5th month - type II alvelolar epithelial cells develop |
|
|
Term
| What cells produce surfactant? |
|
Definition
| type II alvelolar epithelial cells? |
|
|
Term
| At what stage in lung development does the fetus become viable? Why? |
|
Definition
| during the terminal sac phase - weeks 25/26 and on because type I alveolar cell epithelial cells are capable of gaseous exchange |
|
|
Term
| What occurs during the alveolar period and when does it happen during development? |
|
Definition
-growth of lungs due to mature alveoli. Increase in surface area where alveoli and capillaries meet
-starts at 8th month of development and continues until age 10 |
|
|
Term
| What is the septum transversum and how does it develop? |
|
Definition
-separates the throacic cavity and abdominal cavity
-develops from body wall after lateral body folding is completed |
|
|
Term
| What are the pericardioperitoneal canals? |
|
Definition
| communication between the abdominal and thoracic cavity that remains |
|
|
Term
| Explain the embryologic developments that occur to result in on peridcardial cavity and two pleural cavities |
|
Definition
-fibrous pericardium forms from the pleuopericardial folds and extends caudally until it inttersects with the septum transversum
-as the pleuropericardial folds attach to the primitive mediastinum it separates the heart from the lungs creating a pericardial cavity and two pleural cavities |
|
|
Term
| The diaphargm develops from which four structures? |
|
Definition
1. lateral body wall mesoderm
2. septum transversum
3. dorsal mesentery of the esophagus
4. pleuroperitoneal folds |
|
|
Term
| Explain the development of the diaphragm |
|
Definition
| The diaphrgam develops initially in a more cephalic region and decends caudally into the thoracic position. Phrenic nerves travel with the diaphragm and end up in the fibrous pericardium |
|
|
Term
| Where does the phrenic nerve found? |
|
Definition
| embedded in the fibrous pericardium as it travels with the diaphragm during development |
|
|
Term
| What is the diaphragm innerveated by? |
|
Definition
| 3-5th cervical spinal cord segments via phrenic nerve |
|
|
Term
| What is the earliest lung malformation? |
|
Definition
| Agenesis fom fialure of two bronchial buds to form from the larynx (lung bud) |
|
|
Term
| What condition results from an errorrs of development during the pseudoglandular period? |
|
Definition
-TEF or esophageal atresia
-Congenital diaphragmatic hernia & lung hypoplasia
-abnormal bronchial divison disorders (bronchogenic cysts & pulmonary sequestration) |
|
|
Term
| What is the most common type of TEF? |
|
Definition
|
|
Term
| What is congenital diaphragmatic hernia? |
|
Definition
| herniation of abdominal contents into the chest thorax preventing lung development |
|
|
Term
| Why is CDH most commonly left-sided? |
|
Definition
| nothing preventing herniation - liver on R side |
|
|
Term
| What are the assessment findings associated with CDH? |
|
Definition
scaphoid abdomen and respiratory distress
-usually dx prenatally |
|
|
Term
| Why do we give corticosteriods to preterm babies? |
|
Definition
1. cuboidal --> squamous conversion
2. terminal sac development
3. increase in # of bronchial divisions
4. vasculature development (more capillaries - alveoli connections) |
|
|
Term
| Why are steroid induced growth factors necessary? |
|
Definition
| to facilitate bronchial divisions, vasculature, epithelium, CT development |
|
|
Term
| What congenital condition results from an error in development during the alveolar period? |
|
Definition
| Pulmonary hypoplasia (NOT agenesis) |
|
|
Term
| What is pulmonary hypoplasia? |
|
Definition
-reduced number of bronchioles, terminal bronchioles, alveoli, and arterioles
-often assoc. with Tris 18, 21 |
|
|
Term
| What causes pulmonary hypoplasia? |
|
Definition
1. space occupying lesions (CDH, pleural effusion, small thoracic cage
2. Oligohydramnios - Potter syndrome
3. decreased vascular supply (CHD, TOF, tricuspid atresia, subpulmonic stenosis) |
|
|
Term
| At birth, infants have how many alveoli? |
|
Definition
| 50 million (~5% of total) |
|
|
Term
| By what age does alveolar development stop? |
|
Definition
| 8 years old. 300million alveloi (~95%) |
|
|
Term
| What three disorders result from abnormal bronchial divisions? |
|
Definition
1. bronchogenic cyst
2. pulmonary paranchymal cyst
3. pulmonary sequestration |
|
|
Term
| What are bronchogenic cysts and what is the treatment prescribed? |
|
Definition
-cartilaginous, fluid filled sacs that result from anomalous cell proliferation and differentiation during budding/division of the bronchial tree
-can occur at any point after divisons start
-early onset (<12 weeks) will result in mediastinal cysts
- late onset will result in peripheral cysts
Tx: surgical resection only if experiencing respiratory compromise |
|
|
Term
| What is pulmonary paranchymal cyst? |
|
Definition
-thin walled, elastic tissue, single, multilocular peripheral cysts that are ~75% air filled
-occurs during canalicular period as terminal bronchioles are developing
Tx: surgical resection |
|
|
Term
| What is pulmonary sequestration? |
|
Definition
| -abonromal, accessory bud that retains arterial connections with GI vasculature ==> non fuctional, ectopic lung tissue with no blood supply ==> no gas exchange occurs |
|
|
Term
| What are the different types of pulmonary sequestration? |
|
Definition
1. extralobar (25%)
left sided, subpulmonic and surrounded own/separate pleura.
-may be solid and impair fetal circulation
2. Intralobar (75%)
left-sided, lower lobes w/o separate pleura (within lung lobes)
-often asymptomatic |
|
|
Term
| How is pulmonary sequestration dx and what is the treatment? |
|
Definition
-MRI/MRA and angiography for Dx
-surgical resection - lobectomy or resection en bloc (extralobar sequestration) |
|
|
Term
| What is Cystic adnomatoid malformation (CAM or C-CAM) |
|
Definition
Characterized by:
-abnormal mesenchymal proliferation
-failed maturation of the bronchiolar structures
-adenomatous (CT) overgrowth --> cysts
-cysts communicate directly with tracheobronchial tree and each other |
|
|
Term
| What is congenital lobar emphysema (CLE)? |
|
Definition
overdistention and airtrapping of a lung lobe due to a ball-valve like mechanism
-more common in males, 20% are bilateral, fairly uncommon |
|
|
Term
| What are the common causes of CLE? |
|
Definition
-deficiency of cartilate
-enlarged vascular structure
-overlying mass or intrathroacic mass from lymphadenopathy or bronchogenic cyst |
|
|
Term
| What is the role of surfactant in preventing atalectasis? |
|
Definition
-the water molecules of alveolar fluid is attracted to the water molecules in the air favoring lung collapse
*surfactant breaks the surface tension between these water molecules by disrupting water molecule bonds
==> increases lung compliance |
|
|
Term
| What is surfactant made of? |
|
Definition
| phospholipids and proteins |
|
|
Term
| What stimulates surfactant production? |
|
Definition
| stretching of the air spaces with berathing |
|
|
Term
| During what period do fetal breathing movements occur? |
|
Definition
| alveolar period. Breathin movements condition respiratory muscles and stimulates alveolar development/growth |
|
|
Term
| What is congenital alveolar proteinosis? |
|
Definition
-Surfactant Protein B deficiency
-airway collapse impending because of decreased lung compliance
-increased risk of infection as well
-can cause chronic lung disease (mild) or require lung transplant |
|
|
Term
| Explain meconium aspiration and the neonate |
|
Definition
- meconium may be passed in utero during fetal distress
-meconium is lipid and protein rich and will be irritating to the airway
-if inhaled during birth - causes chemical pneumonitis
-if aspirated into distal airways: inactivates surfactant
==> obstruction via ball-valve like mechanism |
|
|
Term
| What is persistent pulmonary hypertension of the newborn and why does it occur? |
|
Definition
-at birth and in the first few weeks of life, PVR should decrease to allow for adequate blood flow
-IF PVR fails to decrease: R-->L shunt across PDA and/or PFO |
|
|
Term
| Why does hypoxemia result from PPHN? |
|
Definition
| decreased pulmonary perfusion because of high PVR |
|
|
Term
| What are the long-term effects of persistent pulmonary HTN? |
|
Definition
1. hypoxemia
2. decreased cardiac output if no cardic shunt exists
3. cor pulmonale |
|
|
Term
| What are the treatment options for pulmonary hypertension? |
|
Definition
1. correct lesion or underlying disease
2. promote pulmonary artery vasodilation (NO/prostacyclins)
3. increase myocardial contraction
4. diuresis |
|
|
Term
| What is PDA and why does it occur? |
|
Definition
| -when closure of DA fails to take place because of high pulmonary vascular resistance |
|
|
Term
| What are the effects of PDA and PFO? |
|
Definition
| on-going shunting of aortic blood to the lungs or from L-R atria results in pulmonary over-circulation. Long term: pulmonary edema and a fixed increase in pulmonary vascular resistance |
|
|
Term
| What are the characteristics of lung diesease of prematurity? |
|
Definition
RESPIRATORY DISTRESS SYNDROME
-surfactant deficiency due to immature type II pneumocytes
-decreased number or absence of alveoli
-underdeveloped terminal sacs
-thicker/cuboidal epithelium
-wide area between air-spaces and capillaries
POOR OXYGENATION/VENTILATION |
|
|
Term
| What is bronchopulmonary dysplasia? |
|
Definition
-long term sequelae
-arrested lung development bc large and underdeveloped alveoli are less capable of gas exchnage
-reactive bronchi and bronchiole smooth muscle causes obstruction
-inflammation and pulmonary edema
-if severe: pulmonary HTN, interstitial fibrosis with cystic changes |
|
|
Term
| What is the treatment of Lung disease of prematurity? |
|
Definition
-Surfactant instillation
-mecahnical ventilation and supplemental oxygen
-bronchodilators
-steroids
-diurectics
-long term ventilation via trach bc of chronic respiratory failure |
|
|
Term
| Define: ventilation, gas exchange, oxygenation, transport, and regulation. |
|
Definition
ventilation = flow of air in and out of the lungs
gas exchange = diffusion of O2 and CO2
oxygenation: movement of oxygen into the circulation
transport: movement of o2 and co2 via blood and circulatory systems
regulation: control of breathing patterns |
|
|
Term
| What structures belong to the extra-thoracic part of the conducting zone? The intra-thoracic? |
|
Definition
Extra-thoracic:
-nose/mouth, trachea, larynx, pharynx
Intra-thoracic:
-bronchi & bronchioles |
|
|
Term
| What is airway resistence and how is it determined? |
|
Definition
-determined by diameter of the conducting zone structures.
- R= 1/r^4 |
|
|
Term
| Describe the mucous lining and cilia characteristics of of the nose --> terminal bronchioles |
|
Definition
1. globet cells that secrete mucous
2. ciliated epithelium with cilia that constantly beat |
|
|
Term
| Where is the "upper airways" and what structures are inclded? |
|
Definition
-everything above the clavicles/throacic inlet. Extra-throacic parts of conducting zone
-mouth, nose, nasopharynx, soft palate, hypopharynx, pharynx, epiglottis, glottis, larynx, proximal trachea |
|
|
Term
| What are important considerations regarding the upper airways? |
|
Definition
-must remain patent
-must have functioning ciliated epithelium and produce mucous |
|
|
Term
| What is the purpose of the upper airways? |
|
Definition
-move air into the lungs
-humidifying an cleaning debris from air entering the lungs |
|
|
Term
| What are the developmental differences in the upper airways between a child and an adult? |
|
Definition
- more narrow diameter (less tolerance for swelling or occlusion)
- more acute angle of upper airway structures in the infant (facilitates nursing)
-narrowing at the level of the glottis (no cuff needed for ET tubes) |
|
|
Term
| Name the common nasal disorders. |
|
Definition
-Infectious Rhinitis
-allergic rhinitis (acute/chronic)
-nasal polyps (CF)
-sinusitis (may be associated with Kartagener Syndrome) |
|
|
Term
| What is olfactory neuroblastomas? |
|
Definition
-highly malignant tumors composed of neuroblasts encircled by vascularized CT
-located superiorly and laterally in the nose
-originates from neuroendocrine cellsd dispersed in olfactory mucosa |
|
|
Term
| What are the common assessment findings of nasopharyngitis, tonsilitis, and laryngitis? |
|
Definition
-reddedning and slight edema of the mucosa with enlargement of related lymph nodes
-tonsils may be enlarged and covered by exudate
-hoarse voice (laryngitis) |
|
|
Term
| What causes nasopharyngitis, tonsilitis, and laryngitis? |
|
Definition
-usually viral in origin (Rhinovirus, echovirus, adenoviruses, RSV, influenza)
-bacterial infections may be superimposed on viral |
|
|
Term
| What is stridor and what causes it? |
|
Definition
-high pitched whilstling on inspiration due to increased resistance in the extra-thoracic airways
-Extra-thoracic airways are not under the influence of negative intrathroacic pressure during inhalation and so are prone to collapse during inhalation causing stridor |
|
|
Term
| What Is are the common assessment findings of peritonsillar abscess? |
|
Definition
-muffled voice
-drooling
-stridor
-trismus
-will have jaw movement |
|
|
Term
| When do peritonsillar abscesses typically form? |
|
Definition
| early in the second decade of life (early teens) |
|
|
Term
| What causes peritonsillar abscess? |
|
Definition
most often bacterial in origin
-staph aureus, micrococcus aureus, beta-hemolytic strep and anaerobic bacteria |
|
|
Term
| Compare/contrast pertonsillar and retropharyngeal abscess |
|
Definition
Similarities:
-caused by same bacteria (staph aureus, micrococcus aureus, beta-hemolytic strep and anaerobic bacteria)
-common symptoms: muffled voice, drooling, stridor, trismus
Differences:
-PA occurs in second decade of life
-RA occurs >6years old
-RA symptoms include fever, dysphagia
-RA has difficulty opening mouth - direct laryngoscopiy difficult |
|
|
Term
| What does retropharyngeal abscess look like on an Xray image? |
|
Definition
| prominent soft tissue swelling of the posterior pharynx. Much larger space than normal |
|
|
Term
| What is a primary concern in treating someone with epiglottitis? |
|
Definition
| Airway obstruction --> EMERGENCY |
|
|
Term
| What causes epiglottitis? |
|
Definition
haemophilus influenza B (vaccine), bacterial infection, Candida
-between 2-7yrs |
|
|
Term
| What are the s/s of epiglottitis? |
|
Definition
S/S:
-rapid onset (<24 hrs)
-high fever
-no cough
-sore throat
-stridor
-muffled voice
-drooling
-toxic apperance
classic symptom: tripod position. DO NOT MOVE PT head TO ASSESS AIRWAY. |
|
|
Term
| What is laryngeal papillomatosis and what causes this condition? |
|
Definition
-perinatal infection with HPV
-onset: infancy - 4 years |
|
|
Term
| What is the most common congenital anomaly of the airway? |
|
Definition
| laryngomalacia and tracheomalasia |
|
|
Term
| What are some common s/s of laryngomalacia & tracheomalasia |
|
Definition
-inspiratory stridor that worsens with crying
-hypercapnea (hypoventilation)
-bronchoscopy:arytenoid cartilages and all supraglottic structures collapse inward (toward glottis) |
|
|
Term
| What is laryngomalacia/tracheomalasia? |
|
Definition
| Trachea rings not strong enough to maintain patent airway during inhalation |
|
|
Term
| What is a laryngeal web and what is the recommended treatment? |
|
Definition
-congenital condition that results in a thin membrane of soft tissue Typically at the level of the glottis
Treatment: surgical resection bc will present with respiratory distress at birth |
|
|
Term
| Describe the vocal cord movement during inspiration/expiration |
|
Definition
-cords are open during inspiration/phonation
-cords are closed during exhalation and at rest |
|
|
Term
| Where are the vocal cords located? |
|
Definition
| protrude from the lateral walls of the glottis and are stretched and posistied by muscles, ligaments, and cartilage |
|
|
Term
| What happens to the vocal cords to during phonation? |
|
Definition
-the vocal cords move together and are stretched sot aht they vibrate when air moves through
-glottic muscles rotate the thyroid and arytenoid cartilages |
|
|
Term
| Describe vocal cord paralysis |
|
Definition
-may be due to congenital or acquired abnormality of the superior laryngeal nerve and or recurrent laryngeal nerven off of the vagus nerve
-assoc with bain stem injuries, brain tumors, chiari malformations, trauma/birth trauma, increased ICP
-may also result from arytenoid cartilage dislocation and vocal cord hematoma assoc with ETT placement |
|
|
Term
| What condition results from upper airway trauma. |
|
Definition
-compression or direct trauma on tracheal mucosa cuases edema, necrosis, and granuloma formation
-induces subltottic stenosis, laryngotracheomalacia, vocal cord injury |
|
|
Term
| What is a common example of upper airway trauma? |
|
Definition
| post-extubation extrathoracic airway obstruction - 35% |
|
|
Term
| What is laryngotracheobronchitis? |
|
Definition
-also known as Croup
-often occurs seasonally in the winter in 3mos to 3years |
|
|
Term
| What are the symptoms of croup? |
|
Definition
-gradual onset - low grade fever
- bark-like cough
-inspiratory stridor
-no sore throat/normal voice/no drooling, non-toxic appearance |
|
|
Term
|
Definition
| virus - parainfluenza virus A, adenovirus, RSV |
|
|
Term
| What is the classic sign of croup on an xray? |
|
Definition
| "steeple sign" with narrowing of traceal air column at the larynx and distension at the hypopharynx |
|
|
Term
| What is tracheitis and when does it occur? |
|
Definition
| -infection/inflammation of the trachea |
|
|
Term
| What are the symptoms of tracheitis? |
|
Definition
-high fever (higher than that assoc with croup)
-stridor/bark-like cough
-no sore throat/normal or hoarse voice
-toxic appearance
-purulent sputum
-stridor that does not improve with alpha/beta agonist (inhaled racemic epinephrine)
-supplemental O2 requirement but no signs of pneumonia, bronchitis, bronchiolitis |
|
|
Term
|
Definition
| high pitched whislting sounds on exhalation due to obstruction in intrathoracic airways |
|
|
Term
| Compare the extra-thoracic airway vs th intra-thoracic airway |
|
Definition
intra-thoracic airway is under negative pressure of intrathoracic cavity during inhalation but are prone to obstruction during exhalation --> wheezing
extrathoracic airway is not under the negative pressure of the intrathroacic cavity and is prone to collapse during inhalation |
|
|
Term
| Describe the difference in cartilage formation in the trachea, bronchi, and bronchioles |
|
Definition
Trachea: cartilage rings
Bronchi: cartilage plates
Bronchioloes: no cartilage and depend on transpulmonary pressures to remain open |
|
|
Term
| Describe the smooth muscle structure in bronchi and bronchioles |
|
Definition
Bronchi:
-smooth muscles in areas wihtout cartilage plates
Bronchioles
-almost exclusively made of smooth muscle |
|
|
Term
| Describe the innervaiton of bronchi and bronchioles |
|
Definition
-sympathetic nerve fibers that act on beta 2 receptors
-parasympathetic nerve fibers of vagus nerve |
|
|
Term
| What is the effect of epinephrine on the bronchi/bronchioles |
|
Definition
| acts on beta-2 receptors to cause vasodilation |
|
|
Term
| Vasoconstriction in bronchial smooth muscle is caused by what substances? |
|
Definition
| acetylcholine, leukotriences (phosphase lipase A & arachidonic acid metabolism), histamine (anaphylaxis) |
|
|
Term
| What are the different disorders of the intrathroacic conducting zone airways? |
|
Definition
| bronchitis, bronchiolitis, asthma, bronchiectasis |
|
|
Term
| What is bronchitis and what is it caused by? |
|
Definition
-inflammation of the bronchi
-Cause: viral or bacterial infection; may be allergic or irritant
-typically non-obstructive and produces exudate |
|
|
Term
| What is bronchiolitis and how is it caused? |
|
Definition
-constriction and obstruction with mucous, causing distal atelectasis
-Cause: mostly viral (RSV)
-OBSTRUCTIVE respiratory disease - impairs ventilation
-cilia is denuded- impairing airway clearance
-if affects respiratory bronchioles and alveoli --> pneumonitis and impairs oxygenation |
|
|
Term
| What are the signs and symptoms of bronchiolitis? |
|
Definition
-cough
-wheezing
-prolonged exhalation
-decreased breath sounds
-coarse breath sounds
-tachypnea, increased WOB
-hypercarbia, maybe hypoxemia if terminal bronchioles are involved
-fever/concurrent conjunctivitis or otitis media |
|
|
Term
|
Definition
allergic, hypersensitive, inflammatory and obstructive lung disease
*bronchial constriction with swelling and mucous production |
|
|
Term
| What immunglobulin mediates asthma reactions? |
|
Definition
| IgE mediated inflammation: arachidonic acid, leukotrienes, acetylcholine, histamine, prostaglandin D2, platelet aggregating factor, various cytokines |
|
|
Term
| What are the effects of asthma? |
|
Definition
-air trapping/hyperinflation with adjacent atalectasis
-hypercarbia
-hypoxemia when gas exchange is impaired |
|
|
Term
| What is the long-term effect of chronic asthma? |
|
Definition
|
|
Term
| Describe the pathology of asthma |
|
Definition
-IgE mediated inflammation
-increased number and hypertorphy of mucus cells/mucus production
-mucus plugs shed contain whorls of shed epithelium
-bronchial walls infiltrated with eosinophils and macrophages
-increased mast cell activity and histamine release |
|
|
Term
| Describe the process of airway remodeling in asthma |
|
Definition
-Accumulation of mucus: increase in number of globlet cells in the mucosa and hypertrophy of submucosal mucus glands
-chronic inflammation; recruitment of eosinophils, macrophages, and other inflammatory cells
-basement membrane underlying the mucosal epithelium is thickened
-hypertrophy and hyperplasia of smooth muscle cells
ALL LEAD TO FIXED BRONCHIAL CONSTRICTION |
|
|
Term
| What are the pharmacologic treatments for asthma? |
|
Definition
| Bronchodilators and anti-inflammatory agents |
|
|
Term
| What are some examples of bronchodilators and how do they work? |
|
Definition
-beta-2 agonists stimulate sympathetic response (albuterol, racemic ephinephrine, IV terbutaline)
-anticholinergics: block vagal/parasym response (ipraroprium chloride - Atrovent)
-magnesium sulfate: direct smooth muscle relaxant |
|
|
Term
| What anti-inflammatory agents are used to treat asthma? How do they work? |
|
Definition
-steroids: block mediatros of inflammation and stabalizes mast cells (methylprednisolone or prenisolone and inhaled fluticasone)
-mast cell stabalizers - prevents histamine release (Cromolyn sodium - intal
-leukotriene inhibitors (Montelukast sodium - singulair) |
|
|
Term
| Explain the role of leukotrienes in asthma reactions |
|
Definition
| cell membranes injured --> phospholipids generate phospholipases --> arachidonic acid (AA) synthesis --> activates eicosonoid enzymes: cyclooxygenase and lipoxygenase --> lipoxygenase catalyzes the formation of leukotrienes --> bind to G protein coupled receptors that mediate bronchospasm and increased capillary permeability |
|
|
Term
| What is bronchiectasis and who does it affect? |
|
Definition
-permanent dilation of bronchi and bronchioles caused by destruction of the muscle and elastic tissue resulting from chronic bronchitis/bronchiolitis
-common in kids with CF |
|
|
Term
| What conditions can lead to bronchioectasis? |
|
Definition
Congenital/hereditary
-CF, intralobar sequestraion of the lung, immunodef states, Kartagener syndrome
Postinfectious conditions
-necrotizing pneumonia
Bronchial obstruction:
-tumor, foreign bodies, mucus impaction
Other:
-rheumatoid arthritis, SLE, IBD, chronic lung transplant rejection, chronic GVHD after bone-marrow transplant |
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Term
| Explain the general pathway that connects cystic fibrosis and bronchiectasis |
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Definition
| CTFR defect --> impaired mucous clearance --> chronic bacterial infection --> chronic neutrophilic inflammation --> bronchiectasis |
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