Pulmonary Physiology PDF

Pulmonary System Jigna patel, PT, PhD Sheena MacFarlane, PT, DPT, CCS Lecture goals: Pulmonary physiology - ventilation (volume of air in/out of alveoli) - gas exchange (perfusion – alveoli – capillaries) - transport (throughout the body and head) Neural control Function of pulmonar...

Pulmonary System Jigna patel, PT, PhD Sheena MacFarlane, PT, DPT, CCS Lecture goals: Pulmonary physiology - ventilation (volume of air in/out of alveoli) - gas exchange (perfusion – alveoli – capillaries) - transport (throughout the body and head) Neural control Function of pulmonary system 0 exchange oxygen and carbon dioxide between the environment, blood, and tissue temperature homeostasis, which is achieved through evaporative heat loss from the lungs filter and metabolize toxic substances entering the lungs Big picture Air enters the nose and mouth Down to the alveolar sacs Gas exchange at the capillaries Circulation upper body veins send deoxygenated blood to your superior vena cava ↑ int lower body veins empty deoxygenated blood into Pulmonary a your inferior vena cava Vena cava to the right atrium-> right ventricle -> pulmonary artery (only artery with deoxygenated blood) -> both lungs -> gas exchange at the capillaries -> oxygenated blood in pulmonary vein (only vein with oxygenated blood) -> left atrium -> left ventricle -> aorta Draw it! Blood Flow Through the (Pulmonary Circuit) heart CLAB RAT) deoxygenate blood * = # = Oxygenutel beood (Systemic Circuit) Cava-Riant Atrium 1. Vena value tricuspid Right atrium > - Right ventricle 2. Semilitar Pulmonar me pulm ireniy 3. Right Ventricle Arteries Pulmman Arteries > Luny [02 music ! ] 4 -. Veins. 5 Lung - Pulmonary Left atime. Pulmonary 6 value bicuspid Left Ventricle. 7 Left Atrium - value Left Emt forth. 8 Ventricle vena Vin 9. Aorta- various arteries > - capillariesa cava the Veins I bring blood too * heart blood away from arteries = take the heart Vest arteries not defined as deoxygenated/oxygenated blood Aorta to the body and head  Cellular level gas exchange occurs in the lungs between alveolar air and the blood of the pulmonary capillaries. effective gas exchange requires, alveoli to be ventilated -Ventilation and perfused. ventilation (V) refers to the flow of air into and out of the alveoli perfusion (Q) refers to the flow of Hrmn blood to alveolar capillaries blood O majority of oxygen in the blood is bound to hemoglobin within red blood cells small amount of oxygen is physically dissolved in the plasma : voz O 1 molecule of oxygen can bind to the iron atom of a heme group, giving each loten A hemoglobin the ability to transport 4O Iheres - oxygen molecules nih.gov Ventilation Ventilation, or breathing, often misnamed respiration, involves the mechanical movement of gases into and out of the lungs. ‘Volume of air moved with each breath and how it is moved’ (muscles and pressure balances) Lung tissue if spread out = 1/2 a tennis court - Gas exchange occurs mostly in the alveoli with capillaries Some terms…  is Moemer ~ meumice Ventilatory Ventilatory - total #have innoid/ ex air in Minute a * * 500 - - wir of amount exhaled 500 O l inhaled breath durring a total volume of air that is inhaled or exhaled in 1 minute TV> 600 ml, RR > 20 70 – 125 L/min the largest amount of air that a person can inhale and then exhale during a 12- to 15-s interval with maximal voluntary effort  Minute ventilation Minute McArdle and Katch Lung volumes - Measured with Pulmonary Function Tests (PFTs) - spirometry: volume and speed of air blown in and out of your lungs  * Tidal volume: 350 to 500 mL of air is inhaled or exhaled with each breath (TV or VT). * Inspiratory reserve volume: additional volume of air that can be taken into the lungs beyond the normal tidal inhalation (IRV). * Expiratory reserve volume: additional volume of air that can be let out beyond the normal tidal exhalation (ERV). o Residual Volume: volume of air that remains in the lungs after a forceful expiratory effort (RV). Air left to keep lungs open. unurs after tre lettall out Lung Capacities - Sum of 2 or more lung volumes mi 2 or of Sum luns volumes  inspiratiy ficel + reserve * N Inspiratory capacity: sum of the tidal and inspiratory reserve volumes; it is the maximum amount of air that can be inhaled after a normal tidal exhalation (IC). Functional residual capacity: sum of the expiratory reserve ↳ and RV; it is the amount of air remaining in the lungs at the end of a normal tidal volume exhalation. - represents the point at which the forces tending to collapse the lungs are balanced against the forces tending to expand the chest wall (FRC). (linked to obstructive lung disorders) Vital capacity: sum of the inspiratory reserve, tidal, and -y fine , mus expiratory reserve volumes; it is the maximum amount of air that can be inhaled following a maximum exhalation (VC). (linked to restrictive lung disorders) inspiratory , How can expiratevy O im tod yet Total lung capacity: maximum volume to which the lungs * can be expanded; it is the sum of all the lung volumes (TLC). => = Tidal + Inspiratory reserva volume = Residual + expiratory reserve volume expiratof Tichl that = volume of air = Inspiratory + o reserve after volume remains in Lungs receive effect value force ful expiratory CRV) (Airlett T tole = Sum of all Luny Volume) , name Max Lures can be expanded to  * - Diaphragm and external intercostals A Internal intercostals and abdominals ↳ In a closed environment – related to how the lungs work Inspiration Atmospheric = 760 mmHg Intrapulmonic same midway between inspiration or expiration Ga Inspiration: diaphragm and external intercostals contract and negative pressure inside compared to atmosphere so air flows into the lungs Expiration O Diaphragm relaxes – ascends – umbrella shape Chest wall muscles relax – rib cage goes back to normal shape Intrapulmonic pressure greater than atmospheric Air exits the lungs Remember bucket handle and * water pump for both inspiration and expiration  Visceral pleura attached to lungs Parietal pleura attached to ribs, muscles etc. - Space in between = intrapleural space - Always negative and less than intrapulmonic T Creates a negative pressure so lungs stay - inflated and stuck to ribs, muscles etc. - linys - transmural or transpulmonary pressure that allows changes - in lung volume to parallel changes in thoracic excursion can sky during inspiration and expiration. inflatel Physical properties of the lungs to east is it How expand ↑ Distend – malleable – not fibrotic Recoil to natural resting state - a thin film of fluid on the alveolus has a surface tension – collapse the lung tissue Keeps alveoli open – balanced by surface tension, lipoprotein molecules ② - - - Turbulent- spasm, fluid Normal – laminar flow Normal vs smoker lungs smoker's lungs  Gas exchange respiration refers to the process of gas exchange in the lungs facilitated through the process of simple diffusion. serves two major functions, including the replenishment of the blood’s oxygen supply used for oxidative energy production and the removal of carbon dioxide returning from venous blood manufactured as a waste product. for diffusion to occur, there are two requirements: air bringing in oxygen to the lungs (alveolar ventilation) and blood to receive the oxygen and give up carbon dioxide (pulmonary perfusion).  Gas exchange happens at the alveoli /pulmonary capillary interface About 500 million alveoli in human lungs Capillary beds largest in human body Alveoli are separated by a pulmonary septum -containing capillaries 1 cell tissue layer in between capillaries and alveoli ‘clementine bag mesh covering the grapes’  Image of 1 alveolus ~500 million Location where O2 taken in and CO2 released :  02 Anyone on mask, higher % is * Can remember 21% fraction of inspired air – FiO2  A No energy required Ø Restrictive lung diseases can alter the wall and affect diffusion flow blood tewys ↑ to meaa a - ,  flow in ~ blood - the capillaries o Gravit dependent bloodistamal & l Note pai Lungs - to * Ex. Pulmonary embolus  > air infout Ventilation - of the luys - flow to > blood Perfusion - I ratio longs ↳ the 7 O  Some air in conducting airways From R ventricle O A good match = 80% > - vertication ↳ LDL/MM-C0(D) SL/min -  reduced ~.9, except anterior left chest - heart increased * Perfusion is gravity dependent V increases as you descend down the lungs (alveolar size, smaller and more compliant at the base) This is about relatives ↳ PTs want to position patient to optimize V/Q match * a & O Prone: good position for V/Q matching  500 X 12 alveoli goes to ~ Not all air 350 12 ~ 4000 ml/min On air , - but nothing * to transport It O -  Shunt versus dead space air Nu Have the sir Home the Diroch ~ but No blood & No hemoglobi to transport Transport of gases to peripheral tissues  (4 heme molecules each with iron) 14-18 12-16 tolerance * much hemoglobi -o exerviva > too little hemoglobin -- deviances - ample Arterial blood direct >- paintul Indirect Ensur device Leasian Ø Oxygen in blood is primarily carried by Hgb but some dissolved in the plasma ( - include System Control menuka/punds F C Motor) (output) Respirate Center control = medulla/pons whill y - O [Sensoru) (INPUT Detectioi E And aorta changes warne Se a read enerton cause initial increase in ventilation , gradual increase from chemoreceptors  IOT & nurse Ventilation Chemoreceptors to maintain ↑ 1y adarity Balae (Not breative retains n of a ot , , and a rate of et biacmany your Chemoreceptors are located in the brainstem (central – medulla) and peripheral arteries (peripheral - aorta and carotid). ↑ sense alterations inOblood pH, carbon dioxide, and oxygen levels 2 Medulla: These receptors are stimulated when carbon dioxide concentrations rise in the cerebrospinal fluid. Central chemoreceptors facilitate an-increased depth and rate of- carbon dioxide levels and pH in the body. ventilation so as to restore normal Carotid and aorta: These receptors help to increase ventilation in response " put , to increasing levels of carbon dioxide in blood (hypercapnia), as well as low Los oxygen levels in blood (hypoxia). Normal ventilation is driven mostly by the levels of carbon dioxide and very little by oxygen levels. is very sunsite o buste 202 02 our sense ph all , , Hillegass 5th ed. Other receptors receptors - Initint2 Con reflex Irritant receptors: - respont to innirates , - Ctrings Tredon' usa as found within the epithelial layer of the conducting airways and respond to various noxious gases, particulate matter, and irritants, - causing them to initiate a cough reflex. When stimulated, these receptors also cause bronchial constriction - and increase ventilatory rate. Trying to get rid ↳ of bud Stuff fluon is out Hillegass 5th ed.  newborns receptors in prominced More - - in the lens/ircus volume too much you dent have Senses Nuce Sure protect Stretch receptors: to Fot , = ↓ Ventilation excessive luys intention of the These receptors are located along the smooth muscles lining the airways and are sensitive to increasing size and volume within the lung. Stimulation of the ventilatory changes in response to increased - volume and size is termed the Hering–Breuer reflex and is more active in newborns. In adults, this reflex is only active with large increases in the tidal volume, which is especially seen during exercise, and O C protects the - lung from excessive inflation. th Hillegass 5 ed. - seen during exercise receptors Pressures within pulman compilines & checking - J receptor: The juxtapulmonary receptors (J receptors) are located near the pulmonary capillaries and are0- sensitive to increased pulmonary capillary pressures. Om - On stimulation, these receptors initiate a rapid, shallow breathing pattern. - The interstitial J receptors produce a cough reflex with fluid O ( accumulation within the lung in patients with pulmonary edema and pleural effusions. have to Hillegass 5th ed. of You in the lungs fluid much-whin would a pressure  Afferent inputs/ efferent outputs E - cries Sunse in Chemicals - keed to O2 202 , PH FOT O ta , ↑ How balune consides breathing just knowtor we & Netezie a Change repit I receptors in the N in ruf vasu ↑ join/musus start Sureeruns body women you and lead exercising , activate ventilation automatically the initial ↑ in to Dic mussies receive ↑ 0 ⑧ ?????? Week 2 Pulmonary physiology quiz: 2024FA - CARDIOVASCULAR... https://rutgers.instructure.com/courses/317119/quizzes/836174?preview=1 Preview " Assign To # Edit $ Week 2 Pulmonary physiology quiz ! This is a preview of the draft version of the quiz Quiz Type Graded Quiz Points 10 Assignment Group Quiz week 2 Shuffle Answers Yes Time Limit No Time Limit Multiple Attempts Yes Score to Keep Highest ! Attempts 2 View Responses After Last Attempt Show Correct No Answers One Question at a No Time Require Respondus No LockDown Browser Required to View Quiz No Results 1 of 4 9/27/24, 1:28 PM Week 2 Pulmonary physiology quiz: 2024FA - CARDIOVASCULAR... https://rutgers.instructure.com/courses/317119/quizzes/836174?preview=1 Webcam Required No Due For Available from Until Sep 8 Everyone Sep 2 at 8am Sep 8 at 11:59pm Preview ! Correct answers are hidden. Score for this attempt: 10 out of 10 Submitted Sep 27 at 1:27pm This attempt took less than 1 minute. % Question 1 1 / 1 pts Most of the oxygen in blood is dissolved in the plasma. true false % Question 2 1 !/ 1 pts What is the respiratory rate at rest of an adult without pulmonary pathology? 16-20 breaths per minute 12-20 breaths per minute 20-25 breaths per minute 6-10 breaths per minute % Question 3 1 / 1 pts What is the amount of air inhaled or exhaled at rest with each breath (Tidal volume)? 200-300 ml 100-200 ml 700- 1000 ml 2 of 4 9/27/24, 1:28 PM Week 2 Pulmonary physiology quiz: 2024FA - CARDIOVASCULAR... https://rutgers.instructure.com/courses/317119/quizzes/836174?preview=1 350-500 ml % Question 4 1 / 1 pts What is the approximate minute ventilation for an adult at rest? 3 L/min 5 L/min 2 L/min 8 L/min % Question 5 1 / 1 pts Where in the brainstem is the respiratory control center located? pons and medulla midbrain medulla only pons only % Question 6 1 / 1 pts Stimulation ! by the parasympathetic system constricts the bronchi. true false % Question 7 1 / 1 pts Expiration at rest is a passive process. True false % Question 8 1 / 1 pts In an upright position, which lung areas receive the most perfusion? base of the lungs both upper lobes apex of the lungs 3 of 4 9/27/24, 1:28 PM Week 2 Pulmonary physiology quiz: 2024FA - CARDIOVASCULAR... https://rutgers.instructure.com/courses/317119/quizzes/836174?preview=1 right middle lobe and left lingula % Question 9 1 / 1 pts What is the partial pressure of oxygen in air at sea level? 21% 10% 5% 35% % Question 10 1 / 1 pts At rest the body extracts how much percent oxygen from the arterioles? 25% 75% 100% 50% Quiz Score: 10 out of 10 ! 4 of 4 9/27/24, 1:28 PM