Respiratory Physiology PDF

1 RESPIRATORY PHYSIOLOGY Dr. Samantha Solecki, DC, MS Instructor, Biology Thinker. Learner. Motivator. Lover of Anatomy & Physiology [email protected] © 2019 Pearson Education, Inc. ...

1 RESPIRATORY PHYSIOLOGY Dr. Samantha Solecki, DC, MS Instructor, Biology Thinker. Learner. Motivator. Lover of Anatomy & Physiology [email protected] © 2019 Pearson Education, Inc.  2 Learning Objectives *Acquired from the Human Anatomy and Physiology Society (HAPS) with personal additions Describe the four respiratory processes – ventilation, external respiration, internal respiration and cellular respiration. Define pulmonary ventilation, inspiration and expiration. Identify the muscles used during quiet inspiration, during forced inspiration and during forced expiration as well as the nerves responsible for stimulating those muscles. Define and state relative values for atmospheric pressure, intrapulmonary pressure, intrapleural pressure and transpulmonary pressure. State Boyle’s law and relate this law to the specific sequence of events (muscle contractions/relaxations and pressure/volume changes) causing inspiration and expiration. Explain how each of the following affect pulmonary ventilation: bronchiolar smooth muscle contractions, lung and thoracic wall compliance and recoil and pulmonary surfactant and alveolar surface tension. Describe the forces that tend to collapse the lungs and those that normally oppose or prevent collapse. Define, identify and determine values for the respiratory volumes (IRV, TV, ERV and RV) and the respiratory capacities (IC, FRC, VC and TLC). Define and calculate values for minute ventilation and alveolar ventilation. Define anatomical dead space and explain the effect of anatomical dead space on alveolar ventilation and on the composition of alveolar and expired air. State Dalton’s Law and Henry’s Law and relate both laws to the events of external and internal respiration and to the amounts of oxygen and carbon dioxide dissolved in plasma.  3 Learning Objectives *Acquired from the Human Anatomy and Physiology Society (HAPS) with personal additions With respect to external respiration: Describe oxygen and carbon dioxide concentration gradients and net gas movements. Analyze how oxygen and carbon dioxide movements are affected by changes in partial pressure gradients (e.g., at high altitude), surface area, diffusion distance and solubility and molecular weight of the gases. Describe the mechanisms of ventilation-perfusion coupling and predict the effect that reduced alveolar ventilation has on pulmonary blood flow and the effect that reduced pulmonary blood flow has on bronchiole diameter and alveolar ventilation. With respect to internal respiration: Describe oxygen and carbon dioxide concentration gradients and net gas movements. Explain the factors that maintain oxygen and carbon dioxide gradients between blood and tissue cells. With respect to oxygen transport: Describe the ways in which oxygen is transported in blood and discuss the relative importance of each to total oxygen transport. State the reversible chemical equation for oxygen binding to hemoglobin and predict how raising or lowering the partial pressure of oxygen will shift the equilibrium. With respect to the oxygen-hemoglobin saturation curve: Interpret the curve at low and high partial pressures of oxygen. List factors that shift the curve down and to the right and explain how this results in increased oxygen delivery to tissues. List factors that shift the curve up and to the left and explain how this facilitates oxygen binding to hemoglobin in the lungs.  4 Learning Objectives *Acquired from the Human Anatomy and Physiology Society (HAPS) with personal additions With respect to carbon dioxide transport: Describe the ways in which carbon dioxide is transported in blood and discuss the relative importance of each to total carbon dioxide transport. State the reversible chemical equation for the reaction of carbon dioxide and water to carbonic acid and then to hydrogen ion bicarbonate ion. Explain the relationship between pH and hydrogen ion concentration. Predict how changing the partial pressure of carbon dioxide will affect the pH and the concentration of bicarbonate ions in the plasma. Predict how changing the pH or the concentration of bicarbonate ions will affect the partial pressure of carbon dioxide in the plasma. State the reversible chemical equation for carbon dioxide binding to deoxyhemoglobin and predict how changing carbon dioxide concentrations will affect deoxyhemoglobin levels in the tissues and the lungs. Explain how each of the following relates to carbon dioxide transport: carbonic anhydrase, hydrogen ions binding to hemoglobin and plasma proteins, the chloride ion shift, and the oxygen- hemoglobin saturation level. Explain how the respiratory system relates to other body systems to maintain homeostasis. Predict factors or situations affecting the respiratory system that could disrupt homeostasis.  5 Processes of Respiration Pulmonary ventilation (breathing)- movement of air into and out of lungs Respiratory Functions to exchange and change gases system External respiration-O2 and CO2 exchange between lungs and blood Transport of Gases-O2 and CO2 in blood Internal respiration-O2 and CO2 Circulatory exchange between systemic blood system vessels and tissues  6 Respiratory System Figure 22.1 Respiration consists of four processes. Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved  7 The Major Respiratory Organs in Relation to Surrounding Structures Figure 22.2 The major respiratory organs in relation to surrounding structures. Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved  8 Alveoli and the Respiratory Membrane Figure 22.11a Alveoli and the respiratory membrane. Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved  9 Alveoli and the Respiratory Membrane Figure 22.11c Alveoli and the respiratory membrane. Copyright © 2019, 2016, 2013 Pearson Education, Inc. All Rights Reserved  10 BREATHING MECHANICS  11 Mechanics of Breathing Pulmonary ventilation = breathing Pulmonary ventilation consists of two phases Inspiration-gases flow into lungs Expiration-gases exit lungs  12 Pressure Relationships in the Thoracic Cavity Atmospheric pressure (Patm) Pressure exerted by air surrounding body = 1 atmosphere Respiratory pressures described relative to Patm Negative respiratory pressure = less than Patm Positive respiratory pressure = greater than Patm Zero respiratory pressure = Patm  13 Intrapulmonary Pressure Intrapulmonary (intra-alveolar) pressure (Ppul) Pressure in alveoli Fluctuates with breathing (, ) Always eventually equalizes with Patm  14 Intrapleural Pressure Intrapleural pressure (Pip) Pressure in pleural cavity Fluctuates with breathing/Ppul Always a negative pressure (