Ch 22 The Respiration System - PowerPoint Presentation

Ch 22 The Respiration System *** MOVE LECTURE TEST BACK ONE DAY TO NOV. 29 *** 1 ½ DAYS OF LECTURE Students: 10, 3 to read Instructor: 5

The Respiration System I. Overview A. Major Function B. 4 Processes 1. Pulmonary ventilation: 2. External respiration:3. Transport:4. Internal respiration: Respiratory system Circulatory system

II Functional Anatomy of the Respiratory System * Introduction– Major organs Nose, * List all organs from nose to Primary Bronchi: Lungs: Bronchi and their branchesLungs: respiratory bronchioles & alveoli= Respiratory Zone Conducting Zone

Figure 22.2a Ala Root and Bridge Dorsum nasi Apex Naris (nostril) (a) Surface anatomy (b) External skeletal framework A. The Nose for * give anatomy & function when appropriate * Functions * Parts * External Nose i ) * External Nares (nostrils) * Nasal Cavity (internal portion) Alar cartilages Septal cartilage

b. Nasal cavity … Sphenoid sinus Nasal conchae (superior, middle and inferior) Nasal vestibule Nostril Nasal cavity Posterior nasal Aperture ( choana ) Hard palate Soft palate Cribriform plate of ethmoid bone * Internal Nares * Hairs: iv) * Olfactory mucosa * Respiratory mucosa * Tissue: * Seromucous Glands * Lysozyme: * Defensins : * Cilia: * Sensory receptors * Nasal Conchae

*B. Paranasal Sinuses Sphenoid sinus Frontal sinus * In 4 bones = * Functions: * Palate * Hard* Soft *Uvula

C. Pharynx connects nasal cavity and mouth to larynx and esophagus Pharynx Nasopharynx Oropharynx Laryngopharynx * Pharyngotympanic (Eustachian) tube opening * Structure and composition : * Parts: * Pharyngotympanic Tube * Tonsils -- 3 Pharyngeal T. Palantine T. Lingual T.

D. *Larynx Laryngopharynx Epiglottis Larynx Vocal fold Hyoid bone Thyroid Cricoid Epiglottis * Functions all below Airway Sound 2. * Basic Anatomy * Bony Attachment * 9 Cartilages all below Tissue: Thyroid Laryngeal Prominence Cricoid Epiglottis Elastic Cartilage Aryepiglottic Fold Function

9 Laryngeal Cartilages … do all below Cuneiform Corniculate Arytenoid Aryepiglottic Fold Arytenoid Vocal Cords Corniculate Cuneiform *Vocal Folds (cords)*Vocal ligamentsii) *Glottis = d. * Vestibular folds = false vocal cords; Location & Function? False Vocal CordsAre all paired Vocal Cords

E. Trachea = windpipe 1. Location2. *Wall composed of 3 layers : describe and give order? * Mucosa: tissue = *Submucosa: *Adventitia: 3. *Hyaline Cartilage Rings Shape & Function?4. * Trachealis muscle - connects posterior ends of C-cartilage, Function? Hyaline cartilage C-Rings Submucosa Mucosa Seromucous gland in submucosa Lumen of trachea Anterior Esophagus Trachealis muscle Adventitia Mucosa

F. Bronchi and Subdivisions (bronchial tree) Superior lobe of right lung Middle lobe of right lung Inferior lobe of right lung Superior lobe of left lung Left main (primary) Lobar (secondary ) Segmental (tertiary ) Inferior lobe of left lung CONDUCTING ZONE 1. * Right and Left Primary Bronchi: describe & do all below Right: wider, shorter, more vertical Problem?s : Enter lungs at Hilium

2. Branching of Bronchi a. *Lobar Bronchi (secondary): b. *  segmental (tertiary) bronchic. *More Branches d.  BronchiolesSize Function: Terminal Bronchioles Size End of Feed into respiratory bronchiolesBronchial ≠ Bronchiole ** Instructor does “d. Bronchioles”

F. Bronchi and subdivisions … Cart Plates GC = Goblet Cells GL = Gland Tracheal /Bronchial Wall 3 . Histology Characteristics f rom bronchi  bronchioles: FOR LABCartilage rings TOPseudostratified columnar TO ↑smooth muscle (complete ring in bronchioles) TOElastic tissue-- all** Instructor does “3. Histology”

3. Histology … Vein

F. Bronchi & Subdivisions4. Respiratory Zone = Respiratory bronchioles, alveolar ducts, alveolar sacs alveoli Description - Alveolar Duct - Terminal cluster of Alveoli = Aveolar Sac Function Alveolar duct Respiratory bronchiole Alveoli Alveolar sac Alveolar duct Alveolar duct Alveoli Alveolar sac Respiratory bronchioles Terminal bronchiole ** Instructor does “4. Resp. Z one” * See Enlargement on next slide

Alveolar sac Alveoli Alveolar duct

4. Respiratory Zone …b. Respiratory Membrane – gas  liquid Capillary Type II (surfactant- secreting) cell Macrophage Alveoli (gas-filled air spaces) Red blood cell in capillary Alveolar pores Capillary endothelium Fused basement membranes of the alveolar epithelium and the capillary endothelium Alveolar epithelium Respiratory membrane Red blood cell O 2 Alveolus CO 2 Capillary Alveolus Nucleus of type I (squamous epithelial) cell i ) Alveolar & Capillary walls + basement membranes (0.5μm) ii) Alveolar walls = T ype II cuboidal cells secrete: ** Instructor does “b. Resp. Mem .”

b. Respiratory Membrane … Alveolar pores = Alveolar Macrophages Pulmonary Capillary Networks** Instructor does “c & d”

Figure 22.9a Elastic fibers (a) Diagrammatic view of capillary-alveoli relationships Smooth muscle Alveolus Capillaries Terminal bronchiole Respiratory bronchiole

Figure 22.10a Trachea Apex of lung Thymus Base of lung Cardiac notch Lung Pleural cavity Parietal pleura Rib Intercostal muscle Visceral pleura (a) Anterior view. The lungs flank mediastinal structures laterally. II. Functional Anatomy … G. * Lungs Superior Lobe Inferior Lobe Superior Lobe Middle Lobe Inferior Lobe 1. * Lung Structure Describe * Apex, Base, * Lobes * Cardiac Notch * Oblique Fissure Oblique Fissure

Figure 22.10c Right lung Parietal pleura Visceral pleura Pleural cavity Sternum Anterior Root of lung at hilum Left lung (c) Transverse section through the thorax, viewed from above. Lungs, pleural membranes, and major organs in the mediastinum are shown. • Left main bronchus • Left pulmonary artery • Left pulmonary vein 1. Lungs Structure … * Root = bronchi/vascular/nerve bundle * Hilum = site of entry

Oblique fissure Left main bronchus Lobules Pulmonary artery Apex of lung Pulmonary hilum Aortic impression Bronchiopulmonary Segments Served by an individual segmental bronchus 8-9 per side (next slide) Disease often confined to one or a few Lobules Smallest gross unit Served by large bronchiole Stroma: the rest, - connective tissue 1. Lungs Structure … Students: please read this slide and prepare questions for anything that is unclear

Figure 22.11 Right superior lobe (3 segments) Right middle lobe (2 segments) Right inferior lobe (5 segments) Left superior lobe (4 segments) Left inferior lobe (5 segments) Bronchiopulmonary S egment (10 on right; 8-9 on left)

G. Lungs … 2. Blood Supply i ) Pulmonary circulation Pulmonary A is high in nutrients, low in O2.So alveoli get nutrients from capillaries and get O2 as it is diffusing through its cells to capillaries- Pulmonary veins carry venous blood high in O2, but low in nutrients back to heart, including most of that from the bronchial veins ii) Systemic circulation Bronchial arteries carry O2 blood to most tissue other than alveoli Bronchial veins carry some of this blood back to the heart via anastomosesStudents: please read this slide; prepare questions

Figure 22.10c Parietal pleura Visceral pleura Pleural cavity Anterior Posterior Vertebra 3. * Pleaurae = double-layered serosa Amy 2A review * Parietal pleura * Visceral pleura * Pleural fluid * Function:

III. Mechanics of BreathingA. Pressure Relationships in The Thoracic Cavity Atmospheric pressure at sea level = 760 mm Hg 1. Basic Characteristics Air moves from High to Low Pressure Respiratory Pressures in lungs are compared to the Atmospheric pressure ( Patm) around bodyIf Respiratory Pressure = 0, it is the same as Atm and no air is movingNegative respiratory pressure = when respiratory pressure is lower than Atm, air moves into lungs through nosePositive respiratory = when respiratory pressure is greater than Patm then air moves out of lungsStudents: please read this slide; prepare questions if material is unclear.

2. Intrapulmonary Pressure Atmospheric pressure I ntrapulmonary pressure 760 mm Hg 760 = intra-alveolar pressure = P pul = pressure in alveoli Fluctuates with breathingAlways equalizes with PatmAlways at least 4 to 6 mm Hg less than intrapulmonary = Transpulmonary PressureKeeps lungs ‘sucked’ up against chest wallResists lungs recoiling power and alveolar collapse 756 Pleural cavity 3. Intrapleural Pressure = P ip = Pressure in the Pleaural cavity Students: please read this slide; prepare questions …

III. Mechanics of Breathing …B. Pulmonary Ventilation Basic Concepts Moving air in and out of the lungs depends on muscles that change the volume of air in the lungs, and thus change the pressure in the lungs. Pressure (P) varies inversely w/ volume (V): Increase Volume  Decrease Pressure, and vica versa - Then to equalize pressure, air must move from high to low pressure Students: please read this slide; prepare questions …

Passive Inhalation– muscle actions a. Diaphragm contracts: moves down external intercostal Contract: lift rib cage up and out. c. lung volume: expands Fig. 11.7, p. 200 1. Inspiration 2. Expiration Passive Exhalation– muscle actions a. Diaphragm relaxes moves: moves back up b. external intercostals relax Moves: lowers rib cage c. Lung volume : Air goes from High to low and moves out of lungs & Lungs recoil Students: please read this slide; prepare questions …

Figure 22.13 (1 of 2) Sequence of events Changes in anterior- posterior and superior- inferior dimensions Changes in lateral dimensions (superior view) Ribs are elevated and sternum flares as external intercostals contract. Diaphragm moves inferiorly during contraction. External intercostals contract. Inspiratory muscles contract (diaphragm descends; rib cage rises). 2 1 Thoracic cavity volume increases. 3 Lungs are stretched; intrapulmonary volume increases. 4 Intrapulmonary pressure drops (to –1 mm Hg). 5 Air (gases) flows into lungs down its pressure gradient until intrapulmonary pressure is 0 (equal to atmospheric pressure). Inspiration

Figure 22.13 (2 of 2) Sequence of events Changes in anterior- posterior and superior- inferior dimensions Changes in lateral dimensions (superior view) Ribs and sternum are depressed as external intercostals relax. External intercostals relax. Diaphragm moves superiorly as it relaxes. 1 Inspiratory muscles relax (diaphragm rises; rib cage descends due to recoil of costal cartilages). 2 Thoracic cavity volume decreases. 3 Elastic lungs recoil passively; intrapulmonary volume decreases. 4 Intrapulmonary pres- sure rises (to +1 mm Hg). 5 Air (gases) flows out of lungs down its pressure gradient until intra- pulmonary pressure is 0. Exhalation

Forced inspiration and expiration a) Forced inspiration employs pectoralis minor, sternocleidomastoid, erector spinae among other muscles to lift ribcage up faster/expand it out further. This drops the pressure even more b) Forced expiration is uses abdominal and internal intercostal muscles to increase the pressure inside the lungs even more

C. Physical Factors Influencing Pulmonary Ventilation 3 factors Airway resistance – is usu ally low- Is like in blood vessels and reduces the flow- Resistance Increases w/: inflammation Smooth Muscle contraction (asthma) which constricts the airways Drugs: Epinephrine often given to asthmatic to dilate bronchiolesStudents: please read this slide; prepare questions if material is unclear.

C. Physical Factors affecting ventilation … 2. Alveolar Surface Tension Type II (surfactant- secreting) cell Alveolus a. Surface tension of H2O : resists increases in surface area and would cause alveoli to collapse if not for Surfactant b. Surfactant (bio-soap) of Type II cells reduces surface tensionPrevents alveolar collapsePremature babies (<28 weeks) lack surfactant, require assistance Students: please read this slide; prepare questions …

Physical Factors affecting ventilation …3. Lung Compliance Students: please read this slide; prepare questions if material is unclear. = Air Volume taken in w/ given change in pressurea. Normally high:High distensibility & elasticity Low surface tensionb. Diminished byscar tissue (fibrosis) Reduced surfactantDecreased flexibility of thoracic cage Then, More energy is required for inspiration; may even have to use forced ventilation muscles to get the resting amount of air in & out

D. Respiratory Volumes & Pulmonary Function Tests Figure 13.9 1. RESPIRATORY V OLUMES Tidal Volume (TV) Dead Space (SEE NEXT SLIDE) Inspiratory Reserve Volume (IRV) Expiratory Reserve Volume (ERV) Residual Volume = Vital Capacity = TOTAL CAPACITY Students: please read this slide; prepare questions if material …

2. Dead Space = air in the conducting pathway; Bronchi and larger Bronchioles; Anatomical dead space: volume of conducting zone conduits (~150 ml)Alveolar dead space: collapsed or obstructed alveoliTotal dead space: sum of above nonuseful volumes Part of Tidal Volume Students: please read this slide; prepare questions …

Figure 22.16b Respiratory volumes Tidal volume (TV) Amount of air inhaled or exhaled with each breath under resting conditions 3100 ml Inspiratory reserve volume (IRV) Expiratory reserve volume (ERV) Residual volume (RV) Amount of air remaining in the lungs after a forced exhalation 500 ml Amount of air that can be forcefully inhaled after a nor- mal tidal volume inhalation Amount of air that can be forcefully exhaled after a nor- mal tidal volume exhalation 1200 ml 1200 ml Measurement Description Adult male average value 1900 ml 500 ml 700 ml 1100 ml Adult female average value Average values affected by age and gender

Figure 22.16a 2. Pulmonary Function Tests SPIROMETER Minute Ventilation = Tidal Volume X breaths/minute- At rest Forced Vital Capacity = maximum amount of air one can move in and out of lungs- At maximum capacity Students: please read this slide; prepare questions ..

D. Respiratory Volumes … c. Alveolar Ventilation = Alveolar ventilation rate (AVR): when take into account that Dead Space is not contributing to gas exchange - True Minute Ventilation AVR = frequency X (TV – dead space) (ml/min) (breaths/min) (ml/breath) Students: please read this slide; prepare questions …

END OF PPTREVIEW QUESTIONSEXTRA SLIDES

Review A. ID B. ID C. What type of E.T. is found here?

Review Questions The _____________ ______ ________ epithelium of the nasal cavity helps move _________ and gives way to ________ _________ epithelium in the oropharynx to protect against ___________ from food. How many lobar bronchi are there? pseudostratified ciliated columnar friction mucus stratified squamous 5 = 3 right + 2 left lobes

Review Questions The ___________ ________ is where respiratory gases diffuse from air in the ________ to the blood plasma. Intrapleural (P ip ) pressure is always _____ than _____________(P pul ) pressure, otherwise the lungs would do what? respiratory membrane intrapulmonary alveoli less Collapse (atalectasis)

Review Questions Which of the following physical factors would negatively effect pulmonary ventilation? Increased resistance to flow Increased lung compliance Decreased alveolar surface tension D. A and C only E. All of the above _______ _______ is the portion of gas in the lungs that does not participate in active gas exchange. Dead space