GROSS ANATOMY Flashcards
boundaries and extent of pleural cavities
parietal pleura lines thoracic cavity whereas the visceral pleura lines the lungs with a space in between them called the pleural cavity (contains interstitial fluid to facilitate lung movement during respiration whereas the surface tension of pleural fluid sustains lung inflation)
vascular supply and innervations of the visceral and parietal pleurae
parietal pleura: innervated by intercostal nerves
diaphragmatic pleura: innervated by phrenic nerve (C3-C5)
bronchial tree branching pattern (from trachea to terminal bronchiole)
- two components: conducting portion (passage of air) and the respiratory portion (gas exchange)
- conducting portion: trachea (hyaline cartilage and smooth muscle bifurcating at the level of the sternal angle (carina) into right and left principal bronchi
- right principle bronchus: wider, shorter, more vertical, prone to choking; separates into 3 secondary bronchi
- left principle bronchus: longer, narrower, passes below aortic arch; separates into 2 secondary bronchi
- tertiary bronchi are located within each of the ten bronchopulmonary segments (the site prone to disease- can be removed without affecting other segments) and give rise to numerous bronchioles
- terminal bronchiole= most distal branch used for conduction of air and is the beginning of the terminal ventilator unit
pulmonary arteries and pulmonary veins (distribution)
right and left pulmonary ARTERIES carry DEOXYgenated blood from the right ventricle and divide into lobar branches/arteries (follows the secondary bronchi) which divide into segmental branches entering bronchopulmonary segments (follows tertiary bronchi) and then continue to divide at level of the terminal ventilator units until forming half of the capillary plexus
other half of the plexus= OXYgenated blood carried by pulmonary capillaries which unite to form intersegmental pulmonary veins running in CT septa between bronchopulmonary segments and at the hilum, these intersegmental veins form the right and left superior and right and left inferior pulmonary VEINS returning oxygenated blood to the left atrium
costodiaphragmatic recess
space between the costal pleura (covers inside of thoracic wall) and the diaphragmatic pleura (covers the musculature of the diaphragm)
pleurisy
inflammation of parietal pleura producing a localized pain over specific regions of the thoracoabdominal wall or over shoulder if the diaphragmatic pleura is involved
composition of the lung
elastic, light and spongy with high surface area at the level of the alveoli to allow for gas exchange
carina
sickle-shaped elevation of cartilage on the internal aspect of the trachea that signifies the bifurcation of the trachea into the right and left principle bronchi
bronchial tree branching pattern (respiratory zone)
respiratory bronchioles branch into alveolar ducts which enlarge at their termini to form large spaces caused alveolar sacs into which groups of alveoli open (the basic functional unit of gas exchange)
- alveoli are air-filled spaces that have a thin layer of specialized epithelial cells and capillaries allowing for a blood-air interface
- Type I alveolar epithelial cells- gas exchange whereas Type II alveolar epithelial cells- surfactant (phospholipids and hydrophobic proteins to reduce surface tension)
distribution and function of autonomic nerves (also pain that could arise in association with them)
CN X (Vagus)
- parasympathetic: innervates smooth musculature of the AIRWAYS and works as a bronchoCONSTRICTOR and stimulates serous and mucous glands
- sympathetic: innervates smooth musculature of BLOOD VESSELS controlling the blood flow through the lungs as well as inhibiting parasympathetic-induced contraction of the bronchial tree and its secretory function, thus is a bronchodilator
- most of the pain associated with lungs- transmitted by afferent fibers within intercostal and phrenic nerves that supply parietal pleurae
- limited number of afferent fibers from bronchi that accompany sympathetics and pain detected by these fibers is referred over anterior chest wall (T1-T5)
distribution and function of lymphatics
fluid that leaves capillary beds drains into the interstitial space and is captured/filtered by the lymphatic system to prevent accumulation and maintain conditions for efficient oxygen exchange causing lymph nodes to have an accumulation of cell debris, bacterial, foreign particles and carcinogenic cells
- superficial lymphatics: beneath visceral pleura drains–> bronchopulmonary/hilar nodes
- deep lymphatics: drain substance of lungs from periphery–> pulmonary nodes–> hilar nodes drains superiorly to–> tracheobronchial and paratracheal nodes–> bronchomediastinal lymph trunks
enlarged specific lymph nodes and the symptoms they cause
- tracheobronchial: distorts trachea position
- pulmonary or bronchopulmonary: obstruction of conducting portion of an airway causing SOB
- (L) bronchopulmonary nodes: compression of recurrent laryngeal nerve causing changes in voice quality
vagal afferent fibers are distributed to:
mucosae of bronchi- cough reflex
muscles of bronchi- stretch response
interalveolar septae- prevents overexpansion
pulmonary arteries- pressoreceptors (BP)
pulmonary veins- chemoreceptors (blood gas levels)
general landmarks of the lung (apex, anatomic base, clinical base, root, hilum)
apex: extend to root of neck, an inch above the medial aspect of the clavicle
anatomic base: diaphragmatic surface
clinical base: lowermost aspect of the lung’s inferior lobe
root: comprised of a primary bronchus, pulmonary vessels, lymphatics and nerves
hilum: where the root of the lung is located (T5-T7)
surfaces of the lung
costal (beneath ribs), mediastinal and diaphragmatic
