UST General Santos Respiratory System Unit 11 PDF

PRAYER BEFORE CLASS Holy Spirit, Divine Creator, true source of light and fountain of wisdom! Pour forth your brilliance upon my dense intellect, dissipate the darkness which covers me, that of sin and of ignorance. Grant me a penetrating mind to understand, a retentive memory, method and ease of le...

PRAYER BEFORE CLASS Holy Spirit, Divine Creator, true source of light and fountain of wisdom! Pour forth your brilliance upon my dense intellect, dissipate the darkness which covers me, that of sin and of ignorance. Grant me a penetrating mind to understand, a retentive memory, method and ease of learning, the lucidity to comprehend, and abundant grace in expressing myself. Guide the beginning of my work, direct its progress and bring it to successful completion. This I ask through Jesus Christ, true God, and true man, living and reigning with You and the Father, forever and ever. Amen.  UST General Santos School of Health Sciences ANATOMY AND PHYSIOLOGY WITH PATHOPHYSIOLOGY Unit 11: The Respiratory System Course Content Respiratory System Physiology ○ Oxygen and Carbon Dioxide Transport in the Blood ○ Pulmonary Ventilation ○ Lung Volumes and Capacities Diseases of the Respiratory System relevant to the Philippines Diagnostic Tests for Respiratory Disorders relevant to Medical Technologists Unit Intended Learning Outcomes: At the end of the unit, the student must be able to: describe the general functions of the respiratory system integrate an understanding of its physiology with the pathophysiology of common diseases and conditions affecting this system Formative Assessment The respiratory system consists of what organs? External ____ _____ cavity P______ _a____ T______ ___n__i _____ Formative Assessment _ _ _ o_ _ _ b _ _ transports oxygen from lungs to the tissues and carbon dioxide from tissues to the lungs. Formative Assessment A B Identify the processes: A: ________ion B: _______ion Word Roots and Combining Forms alveol/o: alveolus, air sac pulmon/o: lung bronch/o: bronchial tube rhin/o: nose bronchi/o: bronchus sinus/o: sinus bronchiol/o: bronchiole spir/o: breathing laryng/o: larynx thorac/o: chest nas/o: nose trache/o: trachea pharyng/o: pharynx phren/o: diaphragm pneum/o,pneumon/o: air Overview of the Respiratory System RESPIRATORY SYSTEM Consists of structures used to acquire oxygen and remove carbon dioxide from the blood Oxygen: required for the body’s cells to synthesize ATP CO2: by-product of ATP production and must be removed from the blood What is another term for breathing?  Respiration VENTILATION RESPIRATION Movement of air into and out of the lungs Diffusion of gases across plasma membranes 2 major types within the body: Pulmonary respiration (external) ○ Between atmospheric air in the lungs and blood Systemic respiration (internal) ○ Between blood and the body’s cells Høib y, Niels. ( 2011). Re cen t advances in the treatment of Pseudo mo nas ae ruginosa infectio ns in cystic fibrosis. BMC med icine. 9. 3 2. 10.118 6/1 741-701 5-9-32. Why do you think is this important?  Ventilation vs. Respiration Conducting zone: ○ Nose to the smallest air tubes within the lungs ○ Strictly for ventilation Respiratory zone: ○ Solely within the lungs ○ Includes specialized small air tubes and the alveoli ○ Gas exchange occurs here Høib y, Niels. ( 2011). Re cen t advances in the treatment of Pseudo mo nas ae ruginosa infectio ns in cystic fibrosis. BMC med icine. 9. 3 2. 10.118 6/1 741-701 5-9-32. Four simultaneous processes to accomplish gas exchange between air and blood: 1. Ventilation - air moves into and out of the respiratory passages Four simultaneous processes to accomplish gas exchange between air and blood: 1. Ventilation - air moves into and out of the respiratory passages 2. Pulmonary respiration - O2 moves out of the alveolar air and into the blood. CO2 diffuses out of the blood and joins the air in the alveoli. Four simultaneous processes to accomplish gas exchange between air and blood: 1. Ventilation - air moves into and out of the respiratory passages 2. Pulmonary respiration - O2 moves out of the alveolar air and into the blood. CO2 diffuses out of the blood and joins the air in the alveoli. 3. Gas transport - O2 and CO2 travel in the blood to and from cells Four simultaneous processes to accomplish gas exchange between air and blood: 1. Ventilation - air moves into and out of the respiratory passages 2. Pulmonary respiration - O2 moves out of the alveolar air and into the blood. CO2 diffuses out of the blood and joins the air in the alveoli. 3. Gas transport - O2 and CO2 travel in the blood to and from cells 4. Systemic respiration - Gas exchange with the tissues involves the exit of O2 from the blood into cells, while CO 2 exits cells to enter the blood Functions of the Respiratory System Functions of the respiratory system: 1. Regulation of blood pH 2. Production of chemical mediators 3. Voice production 4. Olfaction 5. Protection alter blood pH by changing CO2 levels Functions of the respiratory system: 1. Regulation of blood pH 2. Production of chemical mediators 3. Voice production 4. Olfaction 5. Protection Lungs produce Angiotensin-converting enzyme (ACE) for BP regulation Functions of the respiratory system: 1. Regulation of blood pH 2. Production of chemical mediators 3. Voice production 4. Olfaction 5. Protection Air moving past vocal folds → sound and speech Functions of the respiratory system: 1. Regulation of blood pH 2. Production of chemical mediators 3. Voice production 4. Olfaction 5. Protection Airborne molecules drawn into the nasal cavity Functions of the respiratory system: 1. Regulation of blood pH 2. Production of chemical mediators 3. Voice production 4. Olfaction 5. Protection Prevents microorganisms from entering the body and removing them from respiratory surfaces Muscles of Respiration Muscles of Inspiration Muscles of Expiration Animation showing normal breathing Animation showing how the lungs work. When we breathe, air travels in and out of our lungs through a network of tubes known as airways. The airways have an inner lining and are supported by an outer layer of muscles. Please visit the My Lungs My Life resource for more advice, support and information regarding chest illness - http://mylungsmylife.org Boyle’s Law volume of gas is inversely proportional to pressure (when temperature is constant) Volume of the thoracic cavity increases – volume of the lungs increases and the pressure within the lungs decreases Volume of the thoracic cavity decreases – volume of the lungs decreases and the pressure within the lungs increases Muscles of Respiration Function: change the volume of the thoracic cavity to allow air to flow into and out of the lungs Muscles of Inspiration 1. Diaphragm 2. External intercostal muscles 3. Pectoralis minor 4. Scalene muscles Increase volume of the thoracic cavity Muscles of Inspiration During inspiration: thoracic cavity volume increases Diaphragm contracts, downward movement ○ This downward movement is facilitated by relaxation of the abdominal muscles, which moves the abdominal organs out of the way Muscles of Inspiration External intercostals: elevate the ribs → increases thoracic volume As the ribs are elevated, the costal cartilages allow lateral rib movement and lateral expansion of the thoracic cavity Muscles of Expiration 1. Internal intercostals 2. Abdominal muscles Decrease volume of the thoracic cavity Muscles of Expiration Diaphragm relaxes → move upward External intercostal muscles relax → ribs move downward Abdominal muscles contract → thoracic cavity volume to decrease and push abdominal organs upward into the diaphragm  Quiet breathing vs. Labored breathing During labored inspiration, more air moves into the lungs because all of the inspiratory muscles are active. ○ They contract more forcefully than during quiet breathing, which causes a greater increase in thoracic volume During labored expiration, more air moves out of the lungs due to the forceful contraction of the internal intercostals and the abdominal muscles. ○ This produces a more rapid and greater decrease in thoracic volume than would be produced by the passive recoil of the thorax and lungs Oxygen and Carbon Dioxide Transport in the Blood Hemoglobin Transport of O2 Transport of CO2 Hemoglobin complex protein synthesized by immature red blood cells Four types of hemoglobin molecules: (1) embryonic (2) fetal (3) adult (4) hemoglobin-S Hemoglobin complex protein synthesized by immature red blood cells Four types of hemoglobin molecules: (1) embryonic (2) fetal (3) adult (4) hemoglobin-S Hemoglobin Four (4) subunits, each containing one iron- based heme group This heme group is where oxygen binds One hemoglobin can carry up to four O 2 molecules Transport of Oxygen (O2) Once O2 diffuses through the respiratory membrane into the blood→ transported to all the cells of the body Approximately 98.5% of O2 is transported reversibly bound to hemoglobin within red blood cells Remaining 1.5% is dissolved in the plasma Transport of Carbon dioxide (CO2) Carbon dioxide is formed as a by-product of the breakdown of glucose when cells use O2 to produce ATP CO2 diffuses out of individual cells into the blood NOTE: The blood concentration of CO2 needs to be very tightly regulated because too much CO2 in the blood causes the blood to become acidic Transport of Carbon dioxide (CO2) Three ways CO2 is transported in the blood: 1. dissolved in the plasma 2. bound to hemoglobin 3. converted to bicarbonate ion (HCO3−) Transport of CO2 by Hemoglobin Approximately 23% of CO2 is transported bound to hemoglobin ○ Bind in a reversible fashion to hemoglobin Haldane effect: The smaller the amount of O2 bound to hemoglobin, the greater the amount of CO2 able to bind to it, and vice versa ○ Depends on the location, for example: ○ In tissues (eg, muscles): have low O2, but high CO2 (muscles are where O2 is used up) Hence, greater amounts of CO2 bind to hemoglobin This allows CO2 to be removed from the tissues and to ultimately be brought back to the lungs to be exhaled from the body Transport of CO2 as Bicarbonate Ions This is how majority of CO2 is transported in the blood ○ About 70% of blood CO2 is transported in the form of HCO3 dissolved in either the cytoplasm of red blood cells or the plasma of the blood Carbonic anhydrase: Enzyme in red blood cells that catalyzes the production of carbonic acid (H2CO3−) from CO2 and H2O ○ H2CO3 then dissociates into H+ and HCO3 − shown by the following equation Transport of CO2 as Bicarbonate Ions Thus, as CO2 levels increase, more H+ is produced ○ Result: Higher H+ → Decreased pH (acidic) But this is reversible, hence if CO2 levels decrease, carbonic anhydrase creates H2CO3 upon the combining of H+ and HCO3 ○ Result: Less H+ → Higher pH (alkaline) Transport of CO2 as Bicarbonate Ions Chloride shift ○ Recall that in the tissues, CO2 levels are higher because oxygen is used up ○ In the tissues, HCO3− is removed from the red blood cell by an HCO3−/Cl− antiporter. This process is called the chloride shift. ○ HCO3− diffuses out of the red blood cell while Cl− diffuses in through the antiporter ○ Purpose Maintains electrical neutrality in the RBCs and plasma Removes HCO3− from inside the RBCs Promotes greater CO2 transport Physiological Factors Affecting Gas Transport Chemoreceptors Chemoreceptors are specialized neurons that detect changes in the concentration of specific chemicals ○ Central chemoreceptors: located bilaterally and ventrally in the chemosensitive area of the medulla oblongata ○ Peripheral chemoreceptors: found in the carotid and aortic bodies Effect of Po2 on O2 Transport Hemoglobin is 100% saturated with O2 when four O2 molecules are bound to each hemoglobin molecule in the red blood cells ○ When there is an average of two O2 molecules bound to each hemoglobin molecule, hemoglobin is 50% saturated Oxygen-hemoglobin dissociation curve Describes the percent saturation of hemoglobin in the blood at different blood Po 2 values The saturation of hemoglobin is determined by many factors PRAYER BEFORE CLASS Holy Spirit, Divine Creator, true source of light and fountain of wisdom! Pour forth your brilliance upon my dense intellect, dissipate the darkness which covers me, that of sin and of ignorance. Grant me a penetrating mind to understand, a retentive memory, method and ease of learning, the lucidity to comprehend, and abundant grace in expressing myself. Guide the beginning of my work, direct its progress and bring it to successful completion. This I ask through Jesus Christ, true God, and true man, living and reigning with You and the Father, forever and ever. Amen. Regulation of Ventilation Sensitive to changes in CO2 levels and blood pH Local Control Resting ventilation provides body with oxygen it needs Pulmonary capillary perfusion: flow of blood to the alveoli Ventilation-perfusion coupling: the relationship between ventilation of the alveoli and blood flow to the alveoli ○ However, not all of the blood that goes to the lungs is completely saturated with oxygen ○ Blood that is not completely oxygenated is called shunted blood Local Control Two main situations that cause disruption to normal ventilation-perfusion coupling: (1) if there is insufficient blood flow to the (2) if there is insufficient air flow to the alveoli alveoli Local Control Two main situations that cause disruption to normal ventilation-perfusion coupling: (1) if there is insufficient blood flow to the (2) if there is insufficient air flow to the alveoli alveoli inadequate cardiac output after a during an asthma attack when heart attack bronchioles become constricted, alveolar ventilation is reduced Disease states wherein buildup of fluid in alveoli → poor gas diffusion Neural Control Respiratory Areas in the Medulla Dorsal respiratory group ○ Most active during inspiration Ventral respiratory group ○ Active during both inspiration and expiration ○ Contains the pre-Bötzinger complex, which is believed to establish the basic rhythm of respiration Neural Control Respiratory Areas in the Pons Pontine respiratory group (pneumotaxic center) ○ For fine-tuning the breathing pattern ○ Not considered essential for the generation of the respiratory rhythm Generation of Rhythmic Ventilation 1. Starting inspiration ○ Basic rhythm of ventilation established spontaneously by medullary respiratory center 2. Increasing inspiration ○ Once inspiration begins, more and more neurons are gradually activated ○ Leads to progressively stronger stimulation of the respiratory muscles 3. Stopping inspiration ○ Neurons stimulating the muscles of respiration also stimulate the neurons in the medullary respiratory center that are responsible for stopping inspiration ○ Inhibit the neurons that stimulate respiratory muscles Effect of Po2 on Respiratory Rate Carbon dioxide is the principal regulator of respiratory rate, but changes in Po2 can also affect respiration ○ A decrease in O2 below its normal values is called hypoxia ○ E.g., Low PO2 (but normal pH and PCO2) = increase in ventilation rate But within the normal range of Po2 levels, the effect of O2 on the regulation of respiration is only small ○ Only after arterial Po2 decreases to approximately 50% of its normal value does it begin to have a large stimulatory effect on respiratory movements Effect of Pco2 on Respiratory Rate Carbon dioxide = principal regulator ○ Even a small increase in CO2 in the bloodstream triggers a large increase in the rate and depth of ventilation ○ E.g., an increase in Pco2 of only 5 mm Hg causes an increase in ventilation of 100% Hypercapnia: Greater-than-normal amount of CO2 in the blood Hypocapnia: Lower-than-normal amount of CO2 in the blood Effect of pH on Respiratory Rate Central chemoreceptors in the medulla detect changes in blood pH via changes in CO2, but via H+ concentrations directly ○ This is because H+ does not easily cross the blood-brain barrier ○ While carbon dioxide easily diffuses across the blood-brain barrier In contrast, the carotid and aortic bodies detect changes in pH via changes in H+ concentrations directly Effect of pH on Respiratory Rate Low pH (acidic) stimulates the respiratory center ○ Resulting in a greater rate and depth of breathing reducing CO2 levels ○ Hence, blood pH increases to normal levels Low pH implies more CO2 in the blood, hence a greater need to remove it via exhalation (→ greater respiratory rate) Gas Exchange INHALATION Air you inhale through nose/mouth → pharynx → larynx → trachea → bronchi (L and R) → bronchioles → alveoli → capillaries Gas Exchange (Alveoli): Oxygen from the inhaled air diffuses across the thin walls of the alveoli into the bloodstream Carbon Dioxide Diffusion: Carbon dioxide, a waste product, diffuses from the bloodstream into the alveoli. EXHALATION The carbon dioxide-rich air is expelled from the lungs Reverse Path: The air follows the same path back through the bronchioles, bronchi, trachea, larynx, pharynx, and exits through the nose or mouth Disorders & Diagnostic Tests relevant to the Respiratory System Effects of Aging URTI vs LRTI Paralysis of the respiratory muscles Effects of Aging on the Respiratory System Decreased ability to perform intense exercise ○ Decreased ability to fill the lungs with age ○ Decreased ability to empty the lungs with age ○ Result: Decreased minute ventilation → Decreased ability to exercise Alveolar ducts and bronchioles expand in diameter with age ○ Result: Increased residual volume, but the increased size creates more dead space ○ This lowers the amount of air available for gas exchange Effects of Aging on the Respiratory System Increased mucus accumulation within the respiratory passageways ○ With age, mucus becomes more viscous ○ The number of cilia and their rate of movement also decrease ○ Result: The elderly are more susceptible to respiratory infections and bronchitis Strep throat Common cold Pulmonary tuberculosis Pneumonia Upper Respiratory Tract Infections ACUTE PHARYNGITIS characterized by the rapid onset of sore throat and pharyngeal inflammation (with or without exudate) caused by bacteria or virus ○ Most common: Streptococcus pyogenes Upper Respiratory Tract Infections ACUTE PHARYNGITIS: Diagnostics History and Physical exam Tests ○ Rapid antigen test ○ Throat culture Lower Respiratory Tract Infection PNEUMONIA Infection of one or both of the lungs caused by bacteria, viruses, or fungi air sacs fill with fluid or pus Symptoms: ○ Cough (with or without mucus) ○ Fever ○ Difficulty breathing Lower Respiratory Tract Infection PNEUMONIA: Diagnostics Chest X-ray Sputum Gram Stain Culture: sputum or blood  Paralysis of the Respiratory Muscles Effect of spinal cord injury on ventilation Diaphragm ○ Supplied by phrenic nerves (C3-C5) Intercostal muscles ○ Supplied by intercostal nerves, which arise from spinal nerves (T1-T11) What will happen if there’s damage: superior to the origin of phrenic nerve? inferior to the origin of phrenic nerve?  Paralysis of the Respiratory Muscles Effect of spinal cord injury on ventilation Diaphragm ○ Supplied by phrenic nerves (C3-C5) Intercostal muscles ○ Supplied by intercostal nerves, which arise from spinal nerves (T1- T11) Damage superior to the origin of phrenic nerve: paralysis of diaphragm and intercostal muscles → death unless artificial respiration is provided Damage inferior to the origin of phrenic nerve: paralysis of the intercostal muscles Formative Assessment The respiratory system consists of what organs? External ____ _____ cavity P______ _a____ T______ ___n__i _____ Formative Assessment The respiratory system consists of what organs? External nose Nasal cavity Pharynx Larynx Trachea Bronchi Lungs Formative Assessment _ _ _ o_ _ _ b _ _ transports oxygen from lungs to the tissues and carbon dioxide from tissues to the lungs. Formative Assessment H E M o G L O b I N transports oxygen from lungs to the tissues and carbon dioxide from tissues to the lungs. Formative Assessment A B Identify the processes: A: ________ion B: _______ion  A B Formative Assessment Identify the processes: A: INSPIRATion B: EXPIRATion Thank you!  UST General Santos School of Health Sciences ANATOMY AND PHYSIOLOGY WITH PATHOPHYSIOLOGY Unit 11: The Respiratory System Dominican Blessing May God the Father bless us May God the Son heal us May God the Holy Spirit enlighten us Give us eyes to see with, ears to hear with, hands to do the work of God with, feet to walk with, and mouth to preach the word of salvation with; And may the angel of peace watch over us, and lead us at last by the Lord’s gift of the kingdom. Amen.