SDL Modular Tool - Respiration Physiology C40, C41, C42, C43 (Rev 2024) PDF

GULLAS COLLEGE OF MEDICINE Department of Physiology FIRST YEAR (REV.2024) Study guide and reading assignments for the lecturers, SGD preceptors and students...

GULLAS COLLEGE OF MEDICINE Department of Physiology FIRST YEAR (REV.2024) Study guide and reading assignments for the lecturers, SGD preceptors and students RESPIRATION PHYSIOLOGY MODULE WEEK 6 UNIT VII CHAPTER 40 – Principles of Gas Exchange; Diffusion of O2 and CO2 through the Respiratory Membrane Basic knowledge of the concept and understanding Physics of Gas Diffusion and Gas Partial Pressures o Different laws Governing Gas Diffusion ▪ Henry’s law ▪ Graham’s law ▪ Fick’s law ▪ Boyle’s law ▪ Dalton’s law o Define the following terms: ▪ Partial pressure ▪ Net diffusion ▪ Ventilation-perfusion ratio o What are the factors that determine partial pressure of a gas dissolved in a fluid? o Describe the role of vapor pressure of water in respiration Compositions of Alveolar Air and Atmospheric Air are Different o How is air humidified in the respiratory passages? o Partial pressures and composition of respiratory gases as they enter and leave the lungs Diffusion of Gases through the Respiratory Membrane o What comprises the respiratory unit? o What are the different layers of the respiratory membrane? o Total quantity of blood in the capillaries of the lungs o Total surface area and the thickness of the respiratory membrane o Elaborate the factors that determine how rapidly a gas passes through the membrane o Diffusing capacity for O2 and CO2 Clinical correlation / Synthesis Explain the following key principles (you may use examples/ simple correlate): o The pressure is directly proportional to the concentration of the gas molecules o Explain the importance of why alveolar air must be slowly renewed by atmospheric air o Effects of alveolar ventilation on the alveolar partial pressures of CO2 and O2 o Alveolar PCO2 increases directly in proportion to the rate of CO2 excretion o Alveolar PCO2 decreases in inverse proportion to alveolar ventilation  o Explain when: ▪ VA/Q equals zero ▪ VA/Q equals infinity ▪ VA/Q is normal ▪ VA/Q is below normal – concept of physiological shunt ▪ VA/Q is greater than normal – concept of physiological dead space o What are the abnormalities of ventilation-perfusion ratio? ▪ Describe VA/Q in COPD ▪ Abnormal VA/Q in upper and lower normal lung Diffusion of Gases through the Respiratory Membrane o What happens in pulmonary edema? Tables & figures: Figures 40-1, 40-2, 40-6, 40-7, 40-8, 40-9; Table 40-1 Source: Guyton & Hall Textbook of Medical Physiology 14e Unit VII, pages 511-519 *Paying particular attention to the tables and figures UNIT VII CHAPTER 41 – Transport of O2 and CO2 in Blood and Tissue Fluids Basic knowledge of the concept and understanding Transport of Oxygen from the Lungs to the Body Tissues o How O2 and CO2 diffused from alveoli to the pulmonary capillary blood? o How O2 and CO2 diffused from the peripheral capillaries into the tissue fluid? o How is oxygen transported in arterial blood? o What is the effect of tissue metabolism and tissue blood flow rate on interstitial PCO2? o Describe the roles of hemoglobin in O2 transport ▪ Hemoglobin “Buffers” tissue PO2 and helps maintain nearly constant PO2 ▪ The maximum amount of O2 that can combine with hemoglobin of the blood ▪ The amount of O2 released from Hgb when systemic arterial blood flows through the tissues o Explain what O2-Hgb dissociation curve is about ▪ What are the factors that shift the oxygen-hemoglobin dissociation curve? ▪ State its significance for oxygen transport Transport of CO2 in the Blood o What are the chemical forms in which CO2 can be transported? ▪ CO2 can be transported in a dissolved state and in the form of bicarbonate ion Define the following terms: o Bohr and Haldane effects o Carbaminohemoglobin o Oxygen-hemoglobin dissociation curve o Carbon dioxide dissociation curve o Respiratory exchange ratio Clinical correlation / Synthesis Transport of Oxygen from the Lungs to the Body Tissues o How oxygen is taken by the pulmonary blood during exercise Explain the following key principles (you may use examples/ simple correlate): o Increasing blood flow raises interstitial fluid PO2 o Increasing tissue metabolism decreases interstitial fluid PO2 o When atmospheric oxygen concentration changes markedly, the buffer effect of hemoglobin still maintains almost constant tissue PO2 o Effect of BPG causing rightward shift of O2-Hgb dissociation curve in certain conditions ▪ In hypoxia and during exercise o Effect of intracellular PO2 on oxygen usage rate o Effect of diffusion from the capillary to the cell on O2 usage o Effect of blood flow on metabolic use of O2 A patient who has carbon monoxide poisoning o What happens when carbon monoxide combines with hemoglobin? Tables & figures: Figures 41-2, 41-3, 41-5, 41-8, 41-9, 41-10, 41-12, 41-13, 41-14 Source: Guyton & Hall Textbook of Medical Physiology 14e Unit VII, pages 521-530 *Paying particular attention to the tables and figures WEEK 7 UNIT VII CHAPTER 42 – Regulation of Respiration Basic knowledge of the concept and understanding Respiratory Center o Where is the respiratory center located? o What group of neurons control our inspiration and expiration, respiratory rhythm o Purpose of pneumotaxic center and its location o How are respiratory center activities being controlled? Definition of terms, concepts, principles o Hering-Breuer inflation reflex o The phenomenon of “Acclimatization” o Lung “J” receptors Chemical Control of Respiration o Changes in CO2 and H+ concentration and their effect in respiratory center activity Clinical correlation / Synthesis Peripheral Chemoreceptor System o Describe the role of oxygen and chemoreceptors in respiratory control o What happens in a hypoxic state? o Effect of low arterial PO2 on alveolar ventilation o Effects of PCO2, pH and PO2 on alveolar ventilation o What stimulates the chemoreceptors? Where are they located? Regulation of respiration during exercise o How is respiration regulated during exercise? o Explain: Neurogenic control of ventilation during exercise may be a learned response Give factors & conditions that affect respiration o Presence of irritant receptors in the airways o Brain edema o Drug overdose – anesthetics and narcotics o Periodic breathing o Cheyne-Stokes breathing o Sleep apnea – OSA and CSA o Voluntary control of respiration Tables & figures: Figures 42-1, 42-2, 42-4, 42-6, 42-12 Source: Guyton & Hall Textbook of Medical Physiology 14e Unit VII, pages 531-540 *Paying particular attention to the tables and figures UNIT VII CHAPTER 43 – Respiratory Insufficiency – Pathophysiology, Diagnosis, Oxygen Therapy Basic knowledge of the concept and understanding Useful Methods for Studying Respiratory Abnormalities o Measurement of blood pH, CO2 and PO2 Definition of terms, concepts, principles o Maximum expiratory flow o Forced expiratory vital capacity o Forced expiratory volume Clinical correlation / Synthesis Useful Methods for Studying Respiratory Abnormalities o Abnormalities of the maximum expiratory flow volume curve Pathophysiologic changes of Specific Pulmonary Abnormalities (Explain) o Chromic pulmonary emphysema o Pneumonia o Atelectasis o Asthma o Tuberculosis o Hypoxia and Oxygen Therapy ▪ Causes of hypoxia ▪ What is the effect of hypoxia on the body ▪ Usefulness of oxygen therapy in different types of hypoxia o Cyanosis o Hypercapnia o Dyspnea o Artificial respiration – the “Iron Lung” Effect of the resuscitator and the tank respirator on venous return Tables & figures: Figure 43-2, 43-3, 43-4, 43-5, 43-6, 43-7, 43-8, 43-9 Source: Guyton & Hall Textbook of Medical Physiology 14e Unit VII, pages 541-549 *Paying particular attention to the tables and figures