Respiratory I (1) PDF

Respiratory I: Introduction, Respiratory Tract, and Lungs Course Learning Objective: Respiratory: Describe how gas is exchanged in the body by examining and identifying gross and microscopic anatomical structures in the respiratory system. ...

Respiratory I: Introduction, Respiratory Tract, and Lungs Course Learning Objective: Respiratory: Describe how gas is exchanged in the body by examining and identifying gross and microscopic anatomical structures in the respiratory system.  Lecture Learning Objectives 1. Recall the components of the 4. Take three deep breaths and visualize anatomical and functional divisions of what structures the air is passing the respiratory system through in you 2. For each segment of the respiratory 5. Recall the difference between track respiration and ventilation and a. Identify its primary function (in green) describe the processes of each b. Identify its boundaries including c. identify the bolded/labeled anatomical a. Boyle’s law and what allows for structure (including those in the ventilation identification manual) b. The definitions of inhalation and d. link the epithelial lining to its function exhalation e. Innervation and blood supply when c. Muscles of respiration and their actions identified d. The steps of gas exchange 6. Use the anatomical organization and 3. Describe the structures and function of the pleura to describe mechanisms of sound production pulmonary collapse using the anatomical structures involved  LO 1 Organization and Function Provide means of gas exchange required for living cells Oxygen in Carbon dioxide out Partners with the cardiovascular system Respiratory system transports between atmosphere and blood; cardiovascular system transports between lungs and body’s cells Categorization Anatomical: Upper and lower respiratory Lower tracts respiratory tract Functional: Conducting (gas transfer) and respiratory (gas exchange) portion  LO 2 Nose and Nasal Cavity Function Conduction: Open to nasopharynx via choanae Filtration: Vibrissae (hair) Filtration: Lined with pseudostratified ciliated columnar epithelium (respiratory epithelium) with mucin producing goblet cells (G) Drake et al., 2018, Gray’s Conditioning: Highly vascularized Basic Anatomy deep to epithelial layer, 3 nasal concha produce turbulence Olfaction: Olfactory epithelium in superior portion Paranasal sinuses Lined with pseudostratified ciliated columnar epithelium Electron micrograph of pseudostratified ciliated columnar epi.  LO 2 Nasal Cavity  LO 2 Nose and Nasal Cavity Anatomy Nose Nares Nasal cavity Roof: frontal, nasal, cribriform plate (ethmoid), sphenoid Floor: Hard palate (maxillae and palatine) Wall: Maxillae, 3 nasal concha Divided by nasal septum Choanae- opening to nasopharynx Lateral nasal wall, sagittal section  LO 2 Nose and Nasal Cavity Anatomy Nasal concha form nasal meatuses Superior nasal meatus Middle nasal meatus Inferior nasal meatus Nasal cavity Roof: frontal, nasal, cribriform plate (ethmoid), sphenoid Floor: Hard palate (maxillae and palatine) Wall: Maxillae, 3 nasal concha Divided by nasal septum Choanae- opening to nasopharynx  LO 2 Nose and Nasal Cavity Anatomy Paranasal sinuses- Paired air spaces Frontal sinus that communicate with nasal cavity via openings in nasal meatuses Ethmoidal sinus Sphenoidal sinus Frontal Ethmoidal Sphenoidal Opening for Maxillary maxillary sinus Opening for nasolacrimal duct Drake et al., 2018, Gray’s Basic Anatomy  LO 2 Pharynx Extends from posterior nasal cavity to bifurcation of larynx and esophagus Common space for respiratory and digestive tracts (throat) Main function conduction also defense (tonsils)  LO 2 Pharyngeal Pharynx Anatomy tonsils Nasopharynx Superior nasal cavity/soft palate Location of pharyngotympanic tube opening and pharyngeal tonsils Respiratory function- pseudostratified ciliated Palatine columnar epi. tonsils Oropharynx Soft palate to hyoid bone/epiglottis Contains palatine tonsils and lingual tonsils Lingual Respiratory and digestive function- tonsils Nonkeratinized stratified squamous epi. Laryngopharynx Hyoid bone to superior border of esophagus Respiratory and digestive function- Nonkeratinized stratified squamous epi. Stylopharyngeus  Stylopharyngeus Occipital With overlying CN IX LO 2 Pharynx Pharyngeal wall – fascia and Superior three paired pharyngeal pharyngeal constrictor (CN X) muscles constrictor m. form posterior and lateral aspects of pharynx Horn of hyoid Middle pharyngeal Longitudinal pharyngeal constrictor m. muscles elevate pharynx: Stylopharyngeus (CN IX) Salpingopharyngeus (CN X) Inferior Palatopharyngeus (CN X) pharyngeal constrictor m. Pharyngeal The retropharyngeal space – raphe formed by loose connective tissue- separates the pharynx from the vertebral column  LO 2 Occipital Pharynx Surrounding Structures Superior cervical ganglia Vagus n. (CN X) Internal jugular v. Internal jugular vein Common carotid a. Middle cervical Superior cervical ganglia ganglion Vagus nerve Sympathetic trunk Middle cervical ganglia Inferior cervical Inferior cervical Carotid artery ganglia ganglion  LO 2 Occipital Pharynx Choana- opening to Posterior view of internal pharynx- openings nasal cavity to nasal cavity, oral cavity, trachea, and esophagus. Uvula Root of tongue and opening to oral cavity Epiglottis- at laryngeal inlet Piriform recess Esophagus  LO 1 Lower Respiratory Tract Includes both conducting and respiratory portions Larynx Trachea Bronchial tree within lungs Lower respiratory Bronchiole tract Respiratory bronchiole Alveolar duct Alveoli  LO 2 Larynx (voice box) Start of lower respiratory tract; 9 cartilaginous pieces held together by ligaments and muscles Suspended from hyoid, continuous with laryngopharynx (superiorly) and trachea (inferiorly), and anterior to esophagus  LO 2 Larynx Conducts air and produces sound Hyoid Highly mobile and vital for phonation and in guarding airway Thyrohyoid passage ligament Superior to vocal cord- Thyroid nonkeratinized stratified squamous cartilage epi. Cricothyroid Inferior to vocal cord- m. pseudostratified ciliated columnar epi. Thyroid Somatic motor and sensory gland innervation through CN X branches Trachea  Larynx - Hyoid LO 2 Anterior/lateral Superior thyroid notch view Thyrohyoid ligament Anterior Thyrohyoid view membrane Superior Thyroid thyroid notch cartilage Laryngeal prominence Cricoid Cricothyroid cartilage ligament Trachea  LO 2 Larynx – Posterior view Epiglottis Horns of thyroid Epiglottis cartilage Thyrohyoid ligament Corniculate Corniculate and cartilage arytenoid Thyroid cartilage Arytenoid cartilage cartilage Cricoid cartilage Posterior view  LO 2/3 Internal Laryngeal Posterior view Structures Laryngeal inlet is continuous with the vestibule Vestibule is bound inferiorly by the vestibular fold (false vocal folds) Laryngeal ventricles open laterally, bound inferiorly by vocal folds (true vocal folds), and is continuous with the laryngeal saccule Vocal folds create rima glottidis; vestibular folds create rima vestibuli Fold are mucosa overlying ligaments Conus elasticus creates infraglottic space Drake et al., 2018, Gray’s Basic Anatomy  LO 2 Intrinsic Laryngeal Muscles Oblique arytenoid mm. Oblique Transverse Posterior arytenoid arytenoid m. cricoarytenoid mm. m. Oblique Transverse Posterior arytenoid mm. arytenoid m. Thyroarytenoid m. Posterior cricoarytenoid mm. Lateral Cricothyroid cricoarytenoid mm. m. Lateral- superficial Lateral-deep  LO 2/3 Intrinsic Muscles of the Larynx Change shape of internal structures Control the inner dimensions of the vestibule and close the rima vestibuli o Thyroarytenoid Help close the laryngeal inlet o Oblique arytenoid Cause arytenoid cartilage to abduct or adduct (pivot) Open and closes the rima glottidis by pivoting o Posterior and lateral cricoarytenoid o Transverse arytenoid Adjust tension in the vocal ligaments o Vocalis Drake et al., 2018, Gray’s Basic Anatomy  Posterior LO 3 Larynx- Sound Production Thyroid cartilage Arytenoid cartilage Epiglottis Vestibular fold Say “ahhhhhhh” Cricoid cartilage Rima Vocal Vocal fold ligaments glottis Drake et al., 2018, Gray’s Basic Anatomy  LO 2 Laryngeal Innervation Branches of vagus nerve: Superior Superior laryngeal n. laryngeal n. ▪ Internal branch- sensory to internal larynx internal ▪ External branch- cricothyroid mm. only branch Recurrent laryngeal n.- all other muscles Superior laryngeal n. Superior external laryngeal n. branch Recurrent laryngeal nn. Recurrent laryngeal n. Lateral- superficial Lateral-deep  LO 2 Trachea Larynx Continuous with larynx superiorly, anterior to esophagus Trachea Conducts air and provides defense via cilia and mucous production in goblet cells Carina Lined with pseudostratified ciliated columnar epi.  LO 2 Trachea Tracheal cartilage 15 -20 “C” shaped tracheal cartilages connected by elastic CT, and annular ligaments Inferior most cartilage called the carina Trachealis m Trachealis muscle Annular ligament Located at open portion of “C” shaped cartilage is the, allows for expansion (swallowing) and contraction (coughing)  Bronchopulmonary LO 2 segments Lungs Located within pleural cavities on either side of mediastinum Lungs divided into lobes- 2 on left, Pleura three on right- divided by fissures Root or hila of lungs- passage for primary bronchi, pulmonary aa. and vv. Superior lobe Superior lobe Horizontal fissure Oblique fissure Middle lobe Inferior lobe Inferior lobe Oblique fissure Costodiaphragmatic recess  LO 2 Lungs Horizontal fissure Oblique Oblique fissure fissure  LO 2 Lungs Right Left lung lung Superior lobe Horizontal Superior fissure lobe Inferior Middle lobe lobe Inferior lobe  LO 2 Left Lung Root of lung Pulmonary arteries Pulmonary veins Bronchi Groove for esophagus Groove for aorta Cardiac notch/impressions Left lung- medial View into left thoracic cavity  LO 2 Right Lung Root of lung Pulmonary arteries Pulmonary veins Bronchi Groove for esophagus Groove for superior vena cava Groove for azygos vein Cardiac notch/impressions View into right thoracic cavity Right lung- medial  LO 2 Pleura of the Lungs Lungs and internal thoracic wall covered in pleura Visceral pleura- directly on lungs Parietal pleura- on internal thoracic walls and superior surface of diaphragm Pleural cavity is potential space between each layer Pleura can be further defined by location (ex., cervical pleura) Costodiaphragmatic recess- location where serous fluid accumulates in pleural effusion (pathological state where fluid accumulates in pleural cavity) when patient is erect  LO 2 Blood Supply to Lungs Bronchial arteries- directly from anterior aorta and form capillary beds to supply bronchial tree 1. Left superior bronchial a. 2. Left inferior bronchial a. 3. Right bronchial a. 3 Bronchial veins- drain into azygos and accessory hemiazygous veins 1 2 Alveoli and alveolar ducts directly exchange gas directly using pulmonary system instead of bronchial circulation  LO 2 Bronchial Tree Bronchial tree is branched system in lungs beginning with primary bronchi (singular: bronchus) and ends with terminal bronchioles Location for conduction and respiration Made of cartilaginous rings that become less numerous and smaller; eventually become scattered pieces of cartilage Surrounded by a complete ring of smooth muscle From larges to smallest branches transitions from pseudostratified ciliated columnar epithelium → simple columnar → simple cuboidal → simple squamous  LO 2 Bronchial Tree Primary bronchi (right and left) Enter each lung at hilum with vessels and nerves Right more vertical and larger than left Secondary (lobar) bronchi To each lobe Three in right, two in left Tertiary (segmental) bronchi To each broncopulmonary segment 10 in right, 8-10 in left Drake et al., 2018, Gray’s Basic Anatomy  LO 2 Primary Bronchial bronchi Tree 1. Primary 2. Secondary (lobar) 3. Tertiary (segmental) Based on the anatomy, which primary bronchi is more likely to be blocked during aspiration?  LO 2 Bronchial Tree After bronchi: Conducting bronchioles Terminal bronchioles (last conduction portion) Lined by simple columnar or simple cuboidal epithelium No surrounding cartilage Thicker layer of smooth muscle to maintain integrity and to aid in bronchoconstriction and bronchodilation Drake et al., 2018, Gray’s Basic Anatomy  LO 2 Respiratory Portion Respiratory bronchioles Alveolar ducts Alveolar sacs comprised of alveoli (plural: alveolus) Lined by simple cuboidal and simple squamous epithelium No cartilage Openings in walls to allow for respiration will be present Drake et al., 2018, Gray’s Basic Anatomy Respiration and Ventilation Gas exchange between alveoli and pulmonary circulation and movement of gasses  LO 5 Pulmonary Ventilation- Breathing Caused by Muscular actions Atmospheric pressure Intrapulmonary (lung) pressure Movement of thoracic wall (It boils down to) Boyle’s law- “The pressure of a gas during breathing due decreases if the volume of the container increases, to muscular and vise versa” action (e.g., growing container, decreasing pressure)  LO 5 Pulmonary Ventilation- Breathing Inhalation- Expansion of thoracic wall increases volume of the thoracic cavity→ intrapulmonary pressure decreases (e.g., more room for lungs in thoracic cavity, lower pressure) Air flows into lungs from a region of Movement of thoracic wall higher pressure (atmosphere) to a region during of lower pressure breathing due to muscular action Exhalation- Compression of thoracic wall decreased volume of the thoracic cavity (e.g., less room for lungs in thoracic cavity, greater pressure) Intrapulmonary pressure increases and forces air out into atmosphere  LO 5 Muscles of Respiration 1. Diaphragm contraction causes flattening, moves inferiorly, causing expansion of thoracic cavity 2 2. Transversus thoracis 1 Depress ribs Internal view of anterior thoracic wall  LO 5 Muscles of Respiration 1. Serratus posterior 1 superior elevation during inhalation 2. Serratus posterior 5 inferior 4 depression during exhalation 3. Scalenes forced inhalation elevation 2 4. External intercostals elevation during inhalation 5. Internal intercostals depression during forced Anterior view exhalation Posterior view  LO 5 Blood Supply and Gas Exchange Gas enters bronchopulmonary segments via respiratory bronchioles and alveolar ducts lined by simple squamous epithelium 300-400 million alveoli in the lungs Gas is exchanged between respiratory and cardiovascular systems primarily in alveoli 1. Low oxygen blood enters lungs via pulmonary arteries (from right ventricle) 2. Form alveolar capillary plexuses around alveoli where gas exchange occurs across simple squamous epithelium 3. Oxygenated blood leaves via pulmonary veins (to left atrium)  LO 5 Lungs- Blood Supply Pulmonary circulation Conducts blood to and from the gas exchange surfaces of the lungs, replenish oxygen and rids excess carbon dioxide in blood Deoxygenated blood- right atrium→ right ventricle→ pulmonary trunk→ pulmonary arteries→ pulmonary capillary system in lungs Oxygenated blood- pulmonary capillary system in lungs → pulmonary veins → left atrium → left ventricle→ aorta Pleura and Pulmonary Collapse  LO 6 External Lung Structures Lungs and internal thoracic wall covered in pleura Visceral pleura- directly on lungs Parietal pleura- on internal thoracic walls and superior surface of diaphragm Pleural cavity is potential space between each layer Costodiaphragmatic recess  LO 6 Clinical Correlation: Pulmonary Collapse Lungs are similar to an inflated balloon when they are distended If distention is not maintained, the inherent elasticity of the lungs will cause Elastic qualities of lungs them to collapse Lungs in situ remain distended even when airway passages are open (unlike a closed balloon) Parietal pleura- attached to thoracic wall Visceral pleura- attached to lungs Surface tension, maintained by fluid filled pleural cavity, causes lungs to adhere/follow shape of thoracic wall as it changes (think suction)  LO 6 Clinical Correlation: Pulmonary Collapse If a wound penetrates through the thoracic wall or surface of the lungs, air will be sucked into the pleural cavity due to the negative pressure The surface tension adhering lungs to thoracic wall will be broken causing the lung to collapse and exhalation of air Fluid filled potential space in pleural cavity becomes real space Atelectasis Primary atelectasis: collapse failure of a lung to inflate a birth Secondary atelectasis: collapse of a previously inflated lung