9 The Respiratory System Lesson 9.1: Functions and Anatomy of the Respiratory System Lesson 9.2: Respiration: Mechanics and Control Lesson 9.3: Respiratory Disorders and Diseases

Functions and Anatomy of the Respiratory System Chapter 9: The Respiratory System Lesson 9.1 Functions and Anatomy of the Respiratory System

Anatomy of the Respiratory System the nose the nasal cavity the pharynx the larynx the trachea the bronchi the lungs

Anatomy of the Respiratory System

Anatomy of the Respiratory System the nose nares the nasal cavity Lined with mucous membranes to filter and purify Ciliated, olfactory hairs/receptors, nerves and vessels Conchae –scrolls that increase surface area Superior, inferior and middle- 3 passageways Increase turbulence to help filter particles----boogers

Anatomy of the Respiratory System the palate Separates nasal cavity from oral cavity Uvula Cleft palate the sinuses-4 of them (frontal, ethmoidal, sphenoid, maxillary) Lighten head ( holes) warm and humidify air, increase tone © Goodheart-Willcox Co., Inc.

The Upper Respiratory Tract

Anatomy of the Respiratory System the pharynx- 5in Tonsils- lymph Eustachian the larynx 8 plates of cartilage Thyroid cartilage Adams apple Epiglottis Vocal folds the trachea 4 in 5th vertebrae C rings

Anatomy of the Respiratory System the bronchi primary bronchi- R and L R shorter (top lobe) bronchioles the alveoli surfactant pores of Kohn- allow macrophage travel the alveolar capillary membrane Gas exchange (diffusion)

Anatomy of the Respiratory System the lungs- 2.5 pounds, float Mediastinum Central area where heart, esophagus, etc located Left Lung- 2 lobes, indentation for the heart Right Lung- 3 lobes Apex- top sits just below collarbone pleural sac parietal pleura visceral pleura

Respiration: Mechanics and Control Chapter 9: The Respiratory System Lesson 9.2 Respiration: Mechanics and Control

Respiration: Mechanics and Control nonrespiratory air maneuvers control of breathing lung volume

Respiration also known as breathing air always moves from a higher pressure area to a lower pressure area four key tasks involved in respiration pulmonary ventilation- lungs move air in and out * external respiration- oxygen introduction * respiratory gas transport- O2 and CO2 exchange- 10&11 internal respiration- gas exchange at cellular level-10&11

Respiration Boyle’s law Gas volume is inversely proportional to its pressure At rest ( no airflow), intrapulmonary and atmospheric pressure are at 760mm Hg Drop in intrapulmonary pressure= take in air Rise in internal pressure= expel air

Respiration inspiration (inhalation)- active process Diaphragm flattens and external intercostal muscles contract thoracic cavity expands, pulling the lungs to expand pressure decreases to 757mm Hg ( negative pressure/vacuum) expiration (exhalation)- passive process Diaphragm rises and external intercostal muscles relax thoracic cavity shrinks IP pressure rises a little- 763 mmHg (positive pressure/air forced out)

Respiration

Nonrespiratory Air Maneuvers

Control of Breathing 12-15 breaths per minute neural factors- control normal breathing pattern Pons (depth of breath and control of inhale/exhale transition) medulla oblongata (rate) Medulla triggers phrenic and IC nerves Stretch receptors in alveoli (Hering-Breuer)-vagal stimulation to exhale

Control of Breathing chemical factors- CO2 is the trigger! central chemoreceptors: CSF pH ( high CO2 levels increase acidity) CO2 can cross the blood/brain barrier Inspiratory triggers- increase rate and depth of breaths peripheral chemoreceptors: Blood O2 levels (minor monitoring of pH and CO2 levels Mechanoreceptors: at the start of increased muscle activity, until CO2 builds up and chemoreceptors take over Women have a higher RR than Men, Children have a higher RR than adults ( infants 40-60) Exercise increases RR ( duh) by ~50 bpm, position and emotions can also affect RR

Lung Volume Varies static Measure air volume in lungs during regular and forced breathing (can only measure by inhaled/exhaled amount) Tidal Volume= air inhaled in normal breath ( measured for 6+ breaths) Vital capacity- Deepest breath, then forced exhale as much as possible Residual volume- what doesn’t leave – can’t measure- requires math and more advanced measurements

Static Lung Volume functional residual capacity Amount of air left over inspiratory reserve volume Inhale after normal inspiration expiratory reserve volume Total exhale after normal exhale total lung capacity Vital capacity+ residual volume IRV+TV+ERV+RV=~6L

Dynamic Lung Volume- air volume in lungs based on forced expiratory maneuvers Measured by flow-volume meter for several normal breaths forced expiratory volume in one second (normal breath)- how well the lungs expel air forced expiratory volume in one second/forced vital capacity (after deep breath): normal is about 6 seconds Airway diseases such as COPD, emphysema and asthma decrease this value to ~80% Lung related diseases that cause lung stiffness, such as pneumonia or CF decrease BOTH values

Respiratory Disorders and Diseases Chapter 9: The Respiratory System Lesson 9.3 Respiratory Disorders and Diseases

Respiratory Disorders and Diseases upper respiratory tract illnesses- most common Nasopharyngitis= common cold lower respiratory tract illnesses chronic obstructive pulmonary diseases asthma lung cancer

Upper Respiratory Tract Illnesses

Upper Respiratory Tract Illnesses avg = 2-4/ year avoiding URIs cover when sneezing and coughing wash hands don’t touch hands to eyes, nose, mouth Influenza VIRAL 5-20%infected per year 25000 deaths/ year Vaccine Problems? icyimage/Shutterstock.com

Lower Respiratory Tract Illnesses acute bronchitis Inflammation of tracheal and bronchial mm Cough (usually +cold/virus) NSAID, decongestant/expectorant pneumonia Infection of lungs (viral, bacterial, fungal, parasitic) Damage to lung cells causes fluid buildup Gas exchange decreased Xrays, +/- cultures, Abx, and O2 Tuberculosis- mycobacterium tuberculosis Contagious infection of lungs ( can travel to other systems) Some strains resistant to abx 2-4 week confinement/isolation (infected droplets)

Chronic Obstructive Pulmonary Diseases Defined- any lung disorder with long term airway obstruction and difficulty breathing (emphysema and chronic ( > 3 month duration) bronchitis= most common), long term disability, 5% of all deaths in the world (# 3 in the US) causes Smoking- ANY TYPE ( even secondhand or occupational exposure), toxic fumes, pollution, chemicals Increases risk of illnesses, depression, and dyspnea worsens over time living with COPD ( because there is no cure) stop smoking (causes 1/5 deaths per year-addiction) purse-lipped breathing ( technique where inhale through nose, exhale through pursed lips slowly) Respiratory therapy, bronchodilators, anti-inflammatory meds Therapy DOES NOT slow the dz, only quitting

Chronic Obstructive Pulmonary Diseases Emphysema- form of COPD Chronic lung inflammation, alveolar damage, capillary bed damage leading to alveolar rupture- less gas exchange and decreased lung surface area Hyperventilation triggered to dispel extra CO2-“pink puffers” chronic bronchitis Inflammation and excessive mucous obstructs airways Bacteria can thrive trapped in mucous of lungs Inc mucous causes decreased RR and inc Cardiac output Gas exchange still possible “blue bloaters”- hypoxemia and increased residual volume

Asthma asthma attack inflamed and narrowed airways Bronchospasms Increased mucous production Wheezing, tightness, cough caused by family history, allergens or irritants treatment relaxes muscles to expand airways, limiting exposure to allergens 8% of adults and 9% of children xavier gallego morel/Shutterstock.com

Lung cancer 90% from smoking Asbestos, radiation, secondhand smoke, toxins Death within 1 year (slow growth, fast metastasis, lung function loss) Small cell or non-small cell Non more common- slower spread Small metastasizes before detectible tumor forms Both- radiation, chemo, tumor removal if caught early