Anatomy Of The Respiratory System PDF

ANATOMY OF THE RESPIRATORY SYSTEM HSC1007 Anatomy and Physiology 1 Dr Karthik S. Harve Associate Professor and Specialty Lead for Anatomy Health and Social Sciences Cluster Singapore Institute of Technology, SG 138683 [email protected] ...

ANATOMY OF THE RESPIRATORY SYSTEM HSC1007 Anatomy and Physiology 1 Dr Karthik S. Harve Associate Professor and Specialty Lead for Anatomy Health and Social Sciences Cluster Singapore Institute of Technology, SG 138683 [email protected]  SIT Internal LEARNING OUTCOMES FROM TODAY’S LECTURE Structures forming the respiratory system Primary functions of the respiratory system Division of the respiratory system based on structure and function How does the structure of the respiratory system facilitate its function? Mechanics and mechanism of the function of respiration  SIT Internal A COMMON SCENARIO A NOT SO COMMON SCENARIO A SIMPLE URTI (UPPER RESPIRATORY TRACT INFECTION) A SERIOUS LRTI (LOWER RESPIRATORY TRACT INFECTION) Picture source: Wikimedia Commons Picture source: Wikimedia Commons  SIT Internal WHAT STRUCTURES FORM THE RESPIRATORY SYSTEM? sincesomepeople breathethroughtheir mouth Upper Respiratory Tract: some ons includethe - Nasal passages - Pharynx part I - Larynx (level of glottis) tracttoo upperrespiratory Lower Respiratory Tract: - Sub-glottis & Trachea - Bronchi - Bronchiole - Alveolus https://upload.wikimedia.org/wikipedia/commons/a/a4/Upper_respiratory_tract.jpg  SIT Internal UPPER RESPIRATORY TRACT Nasal Passages: helpstosmellthe giraffe - Nasal Vestibule - Nasal Cavities 99 receiving p likeagateway.li gIn PaifgetfefnTnFse Pharynx: - Nasopharynx EE.de ns.t ststmcture - Oropharynx - Laryngopharynx Ff Larynx: has2outlets ia going - Laryngeal inlet - Cavity of larynx 7 - Glottis vocalcords theupperrespiratorytract endshere Modified from: Textbook of Histology and Practical Guide by J P Gunasegaran licensed under creative common  boneyprojections 2 Turbinates  slow down air flow to enable air conditioning & filtering 3 turbinates Goblet cell mbkfh.in h e9shntehe mucusmembraneunder the microscope brissae chancesofrespiratory 1 infections Picture modified from Netter’s Atlas of Human Anatomy, Elsevier Ltd staff Wine Nasal Mucosa: Respiratory Epithelium: Pseudostratified Ciliated Columnar with End Goblet Goblet cells Nasal Vestibule: skin & hair (vibrissae) nucleiarenotatthe Lining respiratory epithelium Roof: Olfactory epithelium samelevel - ciliated columnar cells (move mucus) TF T rds Pictures sourced from: OpenStax, Anatomy & Physiology. thepharynx Lateral walls: Respiratory epithelium - goblet cells (secrete mucus) OpenStax CNX. Feb 26, 2016 http://cnx.org/contents/14fb4ad7- - sensory cells (sneeze, cough) [email protected]. Histology Picture courtesy: Department of Anatomy, Yong Loo Lin School of appearsas  Seromucous glands in lamina propria (beneath epithelium) Medicine, National University of Singapore 117594 thereare  Blood vessels in lamina propria: warm the air though  b anL SIT Internal because then food PHARYNX Nasal septum Nasopharynx don'thavetheurgeto bream Thelarynxandtracheafoodthatis digestedhas 9 1s I narrowandsothere 3pathwaysto Oropharynx goby tbuthenose Yaiaiifares gg Laryngopharynx esophagus whatwe want * goingdownlarynxandto thelungs Vocal cords (Glottis) thingsthatprevent.it *  Sub-glottis 8 ffffhisms Pictures sourced from: OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 26, 2016 http://cnx.org/contents/[email protected]. it i iii Picture modified from Netter’s Atlas of Human Functional significance: Separation of food and air pathways Anatomy, Elsevier Ltd  and e g P SIT Internal Goniene backupmechanism to preventchocking Larynx voiceboxtothe impt commonman  A cartilaginous assembly connected by ligaments & membranes formthestructure  Epiglottis forms the inlet  Thyroid & Cricoid cartilages bound the cavity  Main function: prevent asphyxiation (choking)  Voice production(phonation)  vocal cords (folds)  Muscles move the vocal folds breathing swallowing to.tnynegn Hateand sounds mage Vocal folds pulled away Vocal folds close together ‘Abduction’ ‘Adduction’ Pictures sourced from: OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 26, 2016 (‘Abduction’) (‘Adduction’) http://cnx.org/contents/[email protected]. aᵗYEe  SIT Internal TRACHEA IN NECK & MEDIASTINUM kite c I S.ir t.fi ifiiifiarifiariens Tiani amen.aiens 6thiswerestffn.trache C6 (cricoid cartilage) is 030 leftarfhglav 991 medooth muscle T4 (sternal angle) In in iig Carina(tracheal bifurcation) Picture source: Wikimedia Commons TX I Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd. Picture modified from Netter’s Atlas of Human Anatomy, Elsevier Ltd TRACHEAL CROSS SECTION AND HISTOLOGY Pictures sourced from: OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 26, 2016 ciliated http://cnx.org/contents/14fb4ad7-39a1-4eee- [email protected].  Respiratory Epithelium (1)  Lamina propria (2)  Seromucous glands (3)  Hyaline cartilage (4)  Trachealis (smooth muscle) (6) 1 2 Picture courtesy: Wheater’s Functional Histology, 6th Edition, Elsevier Ltd  SIT Internal THE PRIMARY BRONCHI AND THEIR DIFFERENCES Compared to the left, the right main bronchus is:  More vertical  Wider in diameter wider looker  Shorter in length R L morevertical shorter morehorizontal Clinical Implication Li e Picture modified from Netter’s Atlas of Human Anatomy, Elsevier Ltd Foreign bodies more likely to be aspirated into the right side left right L on R L A bronchoscopic view of the int tracheal bifurcation Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  SIT Internal Case scenario: Previously healthy child presented with Linea cough after aspiration of a metal screw Choking, coughing, neck pain, or struggling to breathe are common presentations of an aspirated foreign body. esophagus The right main bronchus is the most common site of obstruction due to its larger lumen and more vertical orientation. wed Hamidi H, Screw in bronchus. Case study, Radiopaedia.org; https://doi.org/10.53347/rID-52530 Functional Division of the Respiratory Tract Conducting zone: Nose to terminal bronchiole Bronchus:  No gas exchange  anatomical ‘dead’ space (~ 150 ml) - Respiratory epithelial lining - Smooth muscle beneath the epithelium  Nasal passages to terminal bronchiole - Broken cartilage in walls - Seromucous glands  Primary source of airway resistance (bronchi) obstructionof air flow  Airway resistance increases in Asthma Bronchiole: - Lumen diameter 15ml Diaphragm Chest wall +ve intrapleural pressure contracts expands At rest reduced lung expansion -ve Intrapleural pressure decreases further  -ve Intra-alveolar pressure  Inspiration Pictures sourced from: OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 26, 2016 http://cnx.org/contents/[email protected].  SIT Internal CHEST X-RAY: FLUID ACCUMULATION IN PLEURAL CAVITY (EFFUSION) Picture source: Wikimedia Commons Pleural effusion: blunted rightdrained CXR shows normal costophrenic angle hasto be costophrenic angle (Samui K et al. 2017)  itwould 5147958hinues prep PNEUMOTHORAX AND CHEST WALL INJURY tobuild  Presence of air in pleural cavity air in thewrong  May result from rib fractures/stab place wounds to the chest  Positive intrapleural pressure  Shift of trachea and mediastinal structures to opposite side  There may be collapse of lung on the affected side  Consequence  Reduced Alveolar Ventilation Picture courtesy: Karthik Easvur / CC-BY-SA-3.0  SIT Internal THE LUNGS: SURFACES, BORDERS AND MAIN PARTS 2 loaves 3loaves Pygia base sits on the diaphram Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  SIT Internal KEY RELATIONS OF THE LUNGS Bronchusto lobe superior ii iii in families onthe Right Lung lung Left Lung Cross-section of thoracic cavity viewed from below Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  SIT Internal LUNGS: LOBES AND FISSURES Thtricle division a Cardiac notch tongueshape project Right Lung Left Lung Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  SIT Internal BRONCHOPULMONARY SEGMENTS OF THE LUNGS  Lobes  bronchopulmonary (BP) segments  10 BP segments in each lung Each Bronchopulmonary segment has its own  Bronchus (air-supply)  Artery (blood supply) So it is an independent structural and functional unit of the lung Picture modified from Netter’s Atlas of Human Anatomy, Elsevier  SIT Internal FURTHER DIVISIONS OF THE AIRWAYS Size Within the Lung Conducting Zone bronchi bronchioles terminal bronchiole wallsbecome Respiratory Zone veryL respiratory bronchiole Alveolar ducts Alveolar sacs and alveoli Creative Commons Attribution 4.0 International Surface area  SIT Internal CHANGES ALONG THE WALL OF THE TRACHEOBRONCHIAL TREE Secreting cell Cartilage in the Smooth muscle in the Glands in the connective Structure Lining Epithelium in Epithelium wall wall tissue of the wall Loss of Pseudostratification Decrease in height of cells Disappearance of goblet cells Trachea Pictures modified from: OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 26, 2016 Alveolus http://cnx.org/contents/[email protected].  SIT Internal The Alveolus: structure and cells 5 main cell types present : Type 1 pneumocyte  Simple squamous epithelium  1. Capillary gas exchange endothelial cells Type 2 pneumocyte  surfactant (a phospholipid) 2. Type 1 pneumocytes synthesis 3. Type II pneumocytes 4. Interstitial cells: Alveoli vary in size from small alveoli to large alveoli include fibroblasts Interalveolar connections via pores (of Kohn) and mast cells Surfactant lowers surface tension in alveoli to prevent 5. Alveolar their collapse macrophages - digest the debris Lack of surfactant in premature babies  Respiratory distress syndrome Picture modified from Wikimedia Commons  SIT Internal 1 7 THE THORACIC WALL Skeletal components - Ribs - Vertebrae - Sternum - Costal cartilages - Associated ligaments Musculoaponeurotic components - Diaphragm - Intercostal muscles - Suprapleural membrane - Fasciae I Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  Ste m THE THORACIC WALL: KEY LANDMARKS Posterior axillary line Anterior axillary line Midclavicular line Scapular line Mid-axillary line Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  mostfragilepartor joinswiththe 0 vertibrae The Typical Rib if any ftp.fgfffffgmes The Sternum and costal cartilages Picture courtesy: Gray’s Anatomy for students, 3rd Note: Both sternum and ribs contain red bone marrow Edition, Elsevier Ltd. Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd. Question Can you find out what is an ATYPICAL rib ?  SIT Internal JOINTS OF THE RIB CAGE Joints between ribs and vertebrae Picture courtesy: McMinn’s Clinical Atlas of Human Anatomy, 7th Edition, Elsevier Ltd 4 Articular facet of transverse process 5 Articular part of tubercle 17 Neck of rib 18 Non-articular part of tubercle Picture courtesy: Gray’s Anatomy for 23 Upper costal facet of head of rib students, 3rd Edition, Elsevier Ltd. 24 Upper costal facet of vertebral body  SIT Internal CHEST WALL MOVEMENTS FOR RESPIRATION Pump Handle Motion Bucket Handle Motion Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd. Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  Forward movement of sternal body at manubriosternal joint  Increases the anteroposterior diameter of thoracic cavity  Elevation of 6-10 ribs at the costovertebral  Involves 2nd to 5th ribs mainly and sternocostal joints  First rib fixed (no movement)  Increases transverse diameter of the cavity  SIT Internal PRINCIPAL MOVEMENTS FOR RESPIRATION IN ALL 3 DIMENSIONS Increased A-P diameter Increased transverse diameter Increased vertical diameter Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd. DIAPHRAGM: ATTACHMENTS AND INNERVATION hemostimportant muscleofbreathing most imptnervein Phrenic nerves thetribrouspericardium central tothe attaches tendonofthe Origin: Cervical spinal segments C3,4,5 diapuram come ftp.t I iifn ignthine mediastinum superior Picture modified from Netter’s Atlas of Human Anatomy, Elsevier then and middlemediastinum  Ethne's DIAPHRAGM: OPENINGS high SIT Internal et In rtebra c Caval opening O Aortic Esophageal hiatus opening Picture courtesy: Aorta Viewed from below Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd. Picture modified from Netter’s Atlas of Human Anatomy, Elsevier  SIT Internal INTERCOSTAL MUSCLES bothsuppliedby intercostalnerves eachintercostalspacehas muscles 3layersofthese muscles goingsoutwardsand External Intercostal Internalalmost perpendicular Intercostal - Adjacent borders of upper and lower ribs - Adjacent borders of upper and lower ribs - Run downwards & forwards - Run downwards & backwards whentheycontracttheyliftup the lowerribtotheupperrib Internal Intercostal functions External intercostal functions Pulldowntheribs - Depress ribs in forced - Elevate ribs in inspiration expiration - Stiffen chest wall - Stiffen chest wall itsvery TimTheelastic passive Peoplewhohaveasthma orhavenarrowairways is not you eh the therecoilof lungs so Picture modified from Netter’s Atlas of Human Anatomy, Elsevier sufficientforthem they  havehair fordedexpiration INNERMOST LAYER OF INTERCOSTAL MUSCLES: 3 PARTS 1. Transversus thoracis back of sternum to costal cartilages 2. Innermost intercostal side of upper to lower ribs (shafts) on their inner surfaces 3. Subcostalis posterior part of ribs on their inner surfaces Function: Most active in Forced expiration Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  SIT Internal THE INTERCOSTAL SPACE Picture courtesy: McMinn’s Clinical Atlas of Human Anatomy, 7th Edition, Elsevier Ltd Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd. Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  SIT Internal ACCESSORY MUSCLES FOR BREATHING Sternocleidomastoid Expiratory muscles Pectoralis Serratus major anterior Inspiratory muscles Pictures modified from Netter’s Atlas of Human Anatomy, Elsevier Picture courtesy: Gray’s Anatomy for students, 3rd Edition, Elsevier Ltd.  SIT Internal MUSCLES OF RESPIRATION Muscles of Inspiration Accessory Inspiratory Muscles * Muscles of Forced Expiration Diaphragm Scalene muscles Internal Intercostal External Intercostal Sternocleidomastoid Innermost Intercostal Pectoralis Major External Oblique Serratus Anterior Internal Oblique Levator Costarum Transversus Abdominis Erector Spinae Rectus Abdominis These are 6 examples of accessory muscles involved in respiration * Not active during quiet inspiration End of Lecture