Respiration involves three main functions: ventilation, gas exchange, and oxygen utilization. Ventilation is the mechanical process of breathing which moves air in and out of the lungs. Gas exchange occurs through diffusion between the alveoli and capillaries, allowing oxygen to diffuse from the air into the blood and carbon dioxide to diffuse out. Oxygen is then utilized in cellular respiration throughout the body. The document discusses the anatomy and physiology of respiration including the conducting and respiratory zones of the lungs, gas pressures, lung volumes, and disorders that can affect respiration.
The document discusses the physiology of respiration, specifically gas exchange and diffusion through the respiratory membrane. It covers:
1) The steps in respiratory gas exchange - alveolar ventilation, gas exchange in pulmonary capillaries, and delivery of oxygen to tissues and removal of carbon dioxide.
2) Factors that affect the rate of gas diffusion through the respiratory membrane - thickness, surface area, gas diffusion coefficient, and partial pressure difference across the membrane.
3) The concept of partial pressure gradients driving gas exchange between alveolar air and blood, and between systemic blood and tissues. The partial pressures of oxygen and carbon dioxide determine diffusion rates.
- Respiration includes ventilation (breathing), gas exchange between air and blood in the lungs, and oxygen utilization through cellular respiration.
- During inhalation, oxygen diffuses from air into the blood in the lungs and carbon dioxide diffuses from the blood into the air. Exhalation is driven by the elastic recoil of the lungs.
- The lungs contain over 300 million alveoli which have a large surface area for gas exchange and are only one cell thick, facilitating diffusion. Surfactant produced in the alveoli reduces surface tension to keep alveoli open during exhalation.
1. The alveolar-capillary unit is a complex structure that facilitates gas exchange through diffusion between alveoli and surrounding capillaries. It provides a thin barrier and large surface area for oxygen and carbon dioxide exchange.
2. Surfactant, produced by type II alveolar cells, reduces surface tension in alveoli to increase lung compliance and prevent collapse during expiration. It plays several roles including reducing work of breathing and stimulating the lung's immune system.
3. Gas exchange occurs through diffusion as blood passes through alveolar capillaries. Oxygen diffuses into the blood from alveoli while carbon dioxide diffuses out of the blood into alveoli based on partial pressure gradients
lecture 5: it's good for as to take a breif about how does atmospheric air will pass to our lungs then to blood, for transportation and utilization of oxygen and excretion of carbon dioxide. Many issue are related when gas exchange is performed.
The document discusses pulmonary surfactant, which reduces surface tension in the lungs. It describes the composition of surfactant, which contains phospholipids like phosphatidylcholine and proteins. Phosphatidylcholine is the most abundant lipid and reduces surface tension. Surfactant is synthesized in alveolar type II cells and stored in lamellar bodies. Hormones like glucocorticoids and estrogen increase surfactant production through various enzymatic pathways. Surfactant is essential for lung function as it prevents alveolar collapse and facilitates gas exchange.
The document describes the mechanics of respiration including the muscles involved in inspiration and expiration. It discusses the pressure changes that occur during ventilation including the negative pressures in the pleural cavity and alveoli that drive lung inflation. Surfactant is described as reducing alveolar surface tension to prevent lung collapse and its role in hyaline membrane disease seen in premature infants is explained.
The pulmonary circulation transports deoxygenated blood from the right ventricle to the lungs where carbon dioxide is released and oxygen is absorbed. The pulmonary arteries branch extensively and have large diameters to accommodate the stroke volume from the right ventricle with low resistance. Blood flows through the pulmonary capillaries where gas exchange occurs before returning to the left atrium via the pulmonary veins. Regional blood flow is highest in the lower lungs and intermittent in the apices due to hydrostatic pressures. During exercise, blood flow increases throughout the lungs. Pulmonary edema can result from increased capillary pressure from left heart failure.
This document discusses pulmonary defense mechanisms against inhaled particles and pathogens. It describes several factors that affect particles' effects such as diameter, shape, and composition. It then covers the main deposition processes particles undergo in the lungs - impaction, sedimentation, and diffusion. The major lung defense mechanisms discussed are the upper and lower airway filters, macrophage clearance to and via lymphatics, and the immune defenses of the lungs including antimicrobial components, antibodies, complement, antioxidants, and immune cells like macrophages, epithelial cells, neutrophils, mast cells, NK cells, dendritic cells, and cytokines. The adaptive immune response of B and T lymphocytes in the lungs is also briefly mentioned.
The document discusses the physiology of respiration, specifically gas exchange and diffusion through the respiratory membrane. It covers:
1) The steps in respiratory gas exchange - alveolar ventilation, gas exchange in pulmonary capillaries, and delivery of oxygen to tissues and removal of carbon dioxide.
2) Factors that affect the rate of gas diffusion through the respiratory membrane - thickness, surface area, gas diffusion coefficient, and partial pressure difference across the membrane.
3) The concept of partial pressure gradients driving gas exchange between alveolar air and blood, and between systemic blood and tissues. The partial pressures of oxygen and carbon dioxide determine diffusion rates.
- Respiration includes ventilation (breathing), gas exchange between air and blood in the lungs, and oxygen utilization through cellular respiration.
- During inhalation, oxygen diffuses from air into the blood in the lungs and carbon dioxide diffuses from the blood into the air. Exhalation is driven by the elastic recoil of the lungs.
- The lungs contain over 300 million alveoli which have a large surface area for gas exchange and are only one cell thick, facilitating diffusion. Surfactant produced in the alveoli reduces surface tension to keep alveoli open during exhalation.
1. The alveolar-capillary unit is a complex structure that facilitates gas exchange through diffusion between alveoli and surrounding capillaries. It provides a thin barrier and large surface area for oxygen and carbon dioxide exchange.
2. Surfactant, produced by type II alveolar cells, reduces surface tension in alveoli to increase lung compliance and prevent collapse during expiration. It plays several roles including reducing work of breathing and stimulating the lung's immune system.
3. Gas exchange occurs through diffusion as blood passes through alveolar capillaries. Oxygen diffuses into the blood from alveoli while carbon dioxide diffuses out of the blood into alveoli based on partial pressure gradients
lecture 5: it's good for as to take a breif about how does atmospheric air will pass to our lungs then to blood, for transportation and utilization of oxygen and excretion of carbon dioxide. Many issue are related when gas exchange is performed.
The document discusses pulmonary surfactant, which reduces surface tension in the lungs. It describes the composition of surfactant, which contains phospholipids like phosphatidylcholine and proteins. Phosphatidylcholine is the most abundant lipid and reduces surface tension. Surfactant is synthesized in alveolar type II cells and stored in lamellar bodies. Hormones like glucocorticoids and estrogen increase surfactant production through various enzymatic pathways. Surfactant is essential for lung function as it prevents alveolar collapse and facilitates gas exchange.
The document describes the mechanics of respiration including the muscles involved in inspiration and expiration. It discusses the pressure changes that occur during ventilation including the negative pressures in the pleural cavity and alveoli that drive lung inflation. Surfactant is described as reducing alveolar surface tension to prevent lung collapse and its role in hyaline membrane disease seen in premature infants is explained.
The pulmonary circulation transports deoxygenated blood from the right ventricle to the lungs where carbon dioxide is released and oxygen is absorbed. The pulmonary arteries branch extensively and have large diameters to accommodate the stroke volume from the right ventricle with low resistance. Blood flows through the pulmonary capillaries where gas exchange occurs before returning to the left atrium via the pulmonary veins. Regional blood flow is highest in the lower lungs and intermittent in the apices due to hydrostatic pressures. During exercise, blood flow increases throughout the lungs. Pulmonary edema can result from increased capillary pressure from left heart failure.
This document discusses pulmonary defense mechanisms against inhaled particles and pathogens. It describes several factors that affect particles' effects such as diameter, shape, and composition. It then covers the main deposition processes particles undergo in the lungs - impaction, sedimentation, and diffusion. The major lung defense mechanisms discussed are the upper and lower airway filters, macrophage clearance to and via lymphatics, and the immune defenses of the lungs including antimicrobial components, antibodies, complement, antioxidants, and immune cells like macrophages, epithelial cells, neutrophils, mast cells, NK cells, dendritic cells, and cytokines. The adaptive immune response of B and T lymphocytes in the lungs is also briefly mentioned.
Compliance Resistance & Work Of Breathing Zareer Tafadar
This document discusses the mechanics of respiration and resistance to breathing. It covers:
1. Elastic resistance makes up around 65% of total resistance and is due to the elastic recoil of lung tissue and surface tension forces. Lung compliance measures a lung's elastic resistance.
2. Non-elastic resistance accounts for the remaining 35% and includes airway resistance. Dynamic compliance is lower than static compliance due to factors like airway obstruction.
3. Several lung diseases can decrease compliance by increasing elastic or non-elastic resistance, requiring more work from respiratory muscles. Surfactant reduces surface tension forces and the work of breathing.
This document discusses control of respiration and drugs affecting it. It describes the local, peripheral and central control of respiration, including chemoreceptors and respiratory centers in the brainstem. It outlines the normal breathing cycle and various reflexes involved, such as chemoreceptor and non-chemical reflexes. Finally, it examines how various drugs can affect respiration, with opioids, benzodiazepines and inhaled anesthetics often depressing it, while doxapram and nicotine can stimulate respiratory drive.
This document discusses the mechanics of respiration including the muscles involved and pressure changes during breathing. It describes how inspiration is an active process involving contraction of the diaphragm and external intercostal muscles which increases the thoracic cavity volume and decreases intrapleural pressure. Expiration is a passive process involving relaxation of these muscles. Pressures measured include intrapulmonary/intra-alveolar pressure which decreases slightly on inspiration and increases on expiration, and intrapleural/intrathoracic pressure which decreases further on deep inspiration. Applied aspects discussed include airway resistance and effects of diseases like asthma and emphysema.
Ventilation and Perfusion in different zones of lungs.Gyaltsen Gurung
This powerpoint presentation will make you explore about the Perfusion and Ventilation in different zones of lungs with its co-relation with pulmonary tuberculosis.
The document discusses the process of respiration in four parts:
1. Pulmonary ventilation involves breathing air in and out of the lungs through inhalation and exhalation.
2. External respiration is the exchange of oxygen and carbon dioxide between the alveoli in the lungs and blood in the pulmonary capillaries.
3. Internal respiration is the exchange of gases between blood in the systemic capillaries and tissue cells throughout the body.
4. Respiration is regulated through various pulmonary volumes including tidal volume, vital capacity, functional residual capacity, and total lung capacity.
The pulmonary circulation has several key characteristics:
1) It has low pressure and resistance but high compliance, allowing the lungs to accommodate large blood volumes.
2) Pulmonary blood flow increases with elevated pulmonary arterial pressure due to recruitment of new vessels and increased vessel distension.
3) Hydrostatic pressures in the lungs vary based on posture, creating three zones of blood flow.
The document discusses various lung volumes and capacities. It defines minute ventilation as the total volume of air inhaled and exhaled per minute, which for a healthy adult is 6 liters per minute. It also defines tidal volume as the volume of one breath, which is 500ml. Various lung measurement devices and terms are explained such as spirometer, spirogram, anatomic dead space, alveolar ventilation rate, residual volume, forced expiratory volume, expiratory reserve volume, inspiratory reserve volume, functional residual capacity, inspiratory capacity, total lung capacity, and vital capacity.
The respiratory system consists of the upper and lower respiratory tract. The upper tract includes the nose, nasal cavity, pharynx and larynx. The lower tract includes the trachea, bronchi and lungs. The nose warms, moistens and filters inhaled air. The nasal cavity is lined with turbinates and openings of paranasal sinuses. The pharynx is divided into naso, oro and laryngopharynx. The larynx contains cartilages including the thyroid, cricoid and epiglottis and controls airflow into the trachea and esophagus. The trachea begins at the cricoid cartilage and contains incomplete C-shaped cartilaginous rings extending
The document summarizes key aspects of respiratory physiology, including the four main functions of respiration, the mechanisms of pulmonary ventilation, gas exchange, and regulation of breathing. It describes the respiratory cycle of inspiration and expiration, how pressure gradients are established via changes in thoracic cavity size, and the roles of muscles like the diaphragm and intercostals. Pressure and volume changes during inhalation and exhalation are provided. Pulmonary volumes and capacities are defined, including vital capacity and functional residual capacity. Disorders like COPD and pulmonary fibrosis are also mentioned.
Lung volumes and capacities can be measured using spirometry to assess respiratory system efficiency and diagnose respiratory diseases. Key lung volumes include tidal volume, inspiratory reserve volume, expiratory reserve volume, residual volume. Lung capacities are combinations of volumes and include inspiratory capacity, functional residual capacity, vital capacity, and total lung capacity. Spirometry allows direct measurement of most volumes except residual volume, functional residual capacity, and total lung capacity, which require additional tests like helium dilution. Interpretation of spirometry results can distinguish between obstructive and restrictive lung diseases.
The document provides an overview of respiratory physiology, covering the basics of the respiratory system including its functional anatomy and the processes of ventilation, gas exchange, and gas transport. It discusses the respiratory system's key functions of gas exchange, pH regulation, and protection. The summary is:
The document outlines the basics of respiratory physiology, including the functional anatomy of the respiratory system and the processes of ventilation, gas exchange, and gas transport. It covers the respiratory tree, pleural membranes, muscles, and gas laws governing respiration. Key topics are the roles of inspiration, expiration, and alveolar ventilation in oxygen and carbon dioxide exchange via pressure gradients across the lungs.
1. The diaphragm and external intercostal muscles are the primary muscles of inspiration. Expiration is normally passive due to lung elasticity.
2. Lung compliance depends on factors like lung volume, blood volume, and disease processes. Surface tension forces from pulmonary surfactant reduce alveolar collapse.
3. Airway resistance arises from both laminar and turbulent gas flow. Increased resistance occurs from bronchospasm, secretions, and airway collapse related to low lung volume or forced exhalation.
The document discusses pulmonary function tests (PFTs) and their use in evaluating respiratory disorders. It provides details on various PFT measurements including spirometry tests like forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1). Obstructive disorders like asthma decrease FEV1 relative to FVC while restrictive disorders decrease both measurements. PFTs are used to diagnose lung conditions, assess severity, and monitor treatment effectiveness. They provide standardized measurements of respiratory function but must be interpreted along with other clinical information.
The document summarizes key aspects of the respiratory system in 3 paragraphs or less:
1) The respiratory system performs ventilation through breathing, gas exchange between air and blood in the lungs, and cellular respiration utilizing oxygen. Partial pressures and composition of gases change as air moves through the respiratory tract.
2) The conducting zone includes nasal passages and pharynx that warm and cleanse air before it reaches the lungs. The lungs contain alveoli with a large surface area for efficient gas exchange.
3) Breathing is regulated by brainstem centers that control the muscles of inspiration and expiration in response to chemoreceptors monitoring blood gas levels, maintaining homeostasis. Gases are transported via hemoglobin in red blood
This document provides an overview of respiratory physiology. Some key points:
- Gas exchange occurs through diffusion of oxygen from the alveoli into the blood and carbon dioxide from the blood into the alveoli down a partial pressure gradient.
- Fick's law describes how gas diffusion is proportional to surface area and inversely proportional to thickness. The adult lung has a large surface area of 85 square meters for gas exchange.
- Ventilation delivers gas to the alveoli through tidal volumes and respiratory rate. Alveolar ventilation is tidal volume minus dead space.
- Oxygen diffuses into the blood where it binds to hemoglobin. The oxygen-hemoglobin dissociation curve describes this relationship.
This document summarizes respiratory physiology, including the three functions of respiration: ventilation, gas exchange, and oxygen utilization. It describes the mechanics of breathing, the structure and function of the lungs and alveoli, gas exchange in the lungs and blood, and common pulmonary disorders like asthma and emphysema.
Gas exchange between the alveoli and the pulmonary capillary blood occurs by diffusion, as will be discussed in the next chapter. Diffusion of oxygen and carbon dioxide occurs passively, according to their concentration differences across the alveolar-capillary barrier. These concentration differences must be maintained by ventilation of the alveoli and perfusion of the pulmonary capillaries.
Alveolar ventilation brings oxygen into the lung and removes carbon dioxide from it. Similarly, the mixed venous blood brings carbon dioxide into the lung and takes up alveolar oxygen. The alveolar Image not available. and Image not available. are thus determined by the relationship between alveolar ventilation and pulmonary capillary perfusion. Alterations in the ratio of ventilation to perfusion, called the Image not available., will result in changes in the alveolar Image not available. and Image not available., as well as in gas delivery to or removal from the lung.
Alveolar ventilation is normally about 4 to 6 L/min and pulmonary blood flow (which is equal to cardiac output) has a similar range, and so the Image not available. for the whole lung is in the range of 0.8 to 1.2. Image not available. However, ventilation and perfusion must be matched on the alveolar-capillary level, and the Image not available. for the whole lung is really of interest only as an approximation of the situation in all the alveolar-capillary units of the lung. For instance, suppose that all 5 L/min of the cardiac output went to the left lung and all 5 L/min of alveolar ventilation went to the right lung. The whole lung Image not available. would be 1.0, but there would be no gas exchange because there could be no gas diffusion between the ventilated alveoli and the perfused pulmonary capillaries.
Oxygen is delivered to the alveolus by alveolar ventilation, is removed from the alveolus as it diffuses into the pulmonary capillary blood, and is carried away by blood flow. Similarly, carbon dioxide is delivered to the alveolus in the mixed venous blood and diffuses into the alveolus in the pulmonary capillary. The carbon dioxide is removed from the alveolus by alveolar ventilation. As will be discussed in Chapter 6, at resting cardiac outputs the diffusion of both oxygen and carbon dioxide is normally limited by pulmonary perfusion. Thus, the alveolar partial pressures of both oxygen and carbon dioxide are determined by the Image not available. If the Image not available. in an alveolar-capillary unit increases, the delivery of oxygen relative to its removal will increase, as will the removal ...
This document discusses oxygen transport and delivery in the body. It covers:
1. Oxygen is transported bound to hemoglobin (97%) and dissolved in plasma (3%). Oxygen diffuses from alveoli into plasma and binds to hemoglobin in red blood cells.
2. Arterial oxygen content is determined by dissolved oxygen and oxygen bound to hemoglobin. Normal arterial content is 20 ml O2/100ml blood. Venous content is normally 15 ml O2/100ml blood.
3. Oxygen delivery depends on cardiac output and arterial oxygen content. Normal delivery is 1000 ml O2/min. Oxygen uptake by tissues is normally 250 ml O2/min.
The document summarizes the physiology of the pulmonary circulatory system in three parts:
1) It describes the anatomy of the pulmonary vessels and pressures within the pulmonary system. The pulmonary artery branches into two main vessels with low pressure, distributing deoxygenated blood to the lungs.
2) It explains fluid dynamics within the lungs and how pulmonary edema develops if pressures rise above safety thresholds. The lungs maintain a negative interstitial pressure to prevent fluid buildup.
3) It covers fluid in the pleural cavity and how a negative pressure is needed to keep the lungs expanded via lymphatic drainage and fluid reabsorption. Pleural effusions can occur if drainage is blocked.
1. The pulmonary circulation receives the entire cardiac output from the right ventricle and has low pressure and resistance to accommodate large blood flow.
2. Pulmonary arteries are thin-walled and distensible to accommodate stroke volume, while capillaries are dense with anastomoses and veins act as reservoirs.
3. Pulmonary circulation acts as a filter to trap emboli and prevent them from reaching systemic circulation. Gas exchange occurs efficiently in the pulmonary capillaries through which blood passes in about 0.8 seconds.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
A presentation to the ASATT or American Society of Anesthesia Technicians and Technologists at the 2016 ASATT meeting in Chicago, IL was delivered by Kevin Lueders of Bell Medical and Corlius Birkill of Xavant Technologies of South Africa. This power point presentation discusses neuromuscular blocking agents history and usage. It also presented the various methods of monitoring NMBAs with traditional peripheral nerve stimulators and with the new quantitative or objective Train of Four, TOF monitor such as the Stimpod NMS 450 using accelerometry.
Compliance Resistance & Work Of Breathing Zareer Tafadar
This document discusses the mechanics of respiration and resistance to breathing. It covers:
1. Elastic resistance makes up around 65% of total resistance and is due to the elastic recoil of lung tissue and surface tension forces. Lung compliance measures a lung's elastic resistance.
2. Non-elastic resistance accounts for the remaining 35% and includes airway resistance. Dynamic compliance is lower than static compliance due to factors like airway obstruction.
3. Several lung diseases can decrease compliance by increasing elastic or non-elastic resistance, requiring more work from respiratory muscles. Surfactant reduces surface tension forces and the work of breathing.
This document discusses control of respiration and drugs affecting it. It describes the local, peripheral and central control of respiration, including chemoreceptors and respiratory centers in the brainstem. It outlines the normal breathing cycle and various reflexes involved, such as chemoreceptor and non-chemical reflexes. Finally, it examines how various drugs can affect respiration, with opioids, benzodiazepines and inhaled anesthetics often depressing it, while doxapram and nicotine can stimulate respiratory drive.
This document discusses the mechanics of respiration including the muscles involved and pressure changes during breathing. It describes how inspiration is an active process involving contraction of the diaphragm and external intercostal muscles which increases the thoracic cavity volume and decreases intrapleural pressure. Expiration is a passive process involving relaxation of these muscles. Pressures measured include intrapulmonary/intra-alveolar pressure which decreases slightly on inspiration and increases on expiration, and intrapleural/intrathoracic pressure which decreases further on deep inspiration. Applied aspects discussed include airway resistance and effects of diseases like asthma and emphysema.
Ventilation and Perfusion in different zones of lungs.Gyaltsen Gurung
This powerpoint presentation will make you explore about the Perfusion and Ventilation in different zones of lungs with its co-relation with pulmonary tuberculosis.
The document discusses the process of respiration in four parts:
1. Pulmonary ventilation involves breathing air in and out of the lungs through inhalation and exhalation.
2. External respiration is the exchange of oxygen and carbon dioxide between the alveoli in the lungs and blood in the pulmonary capillaries.
3. Internal respiration is the exchange of gases between blood in the systemic capillaries and tissue cells throughout the body.
4. Respiration is regulated through various pulmonary volumes including tidal volume, vital capacity, functional residual capacity, and total lung capacity.
The pulmonary circulation has several key characteristics:
1) It has low pressure and resistance but high compliance, allowing the lungs to accommodate large blood volumes.
2) Pulmonary blood flow increases with elevated pulmonary arterial pressure due to recruitment of new vessels and increased vessel distension.
3) Hydrostatic pressures in the lungs vary based on posture, creating three zones of blood flow.
The document discusses various lung volumes and capacities. It defines minute ventilation as the total volume of air inhaled and exhaled per minute, which for a healthy adult is 6 liters per minute. It also defines tidal volume as the volume of one breath, which is 500ml. Various lung measurement devices and terms are explained such as spirometer, spirogram, anatomic dead space, alveolar ventilation rate, residual volume, forced expiratory volume, expiratory reserve volume, inspiratory reserve volume, functional residual capacity, inspiratory capacity, total lung capacity, and vital capacity.
The respiratory system consists of the upper and lower respiratory tract. The upper tract includes the nose, nasal cavity, pharynx and larynx. The lower tract includes the trachea, bronchi and lungs. The nose warms, moistens and filters inhaled air. The nasal cavity is lined with turbinates and openings of paranasal sinuses. The pharynx is divided into naso, oro and laryngopharynx. The larynx contains cartilages including the thyroid, cricoid and epiglottis and controls airflow into the trachea and esophagus. The trachea begins at the cricoid cartilage and contains incomplete C-shaped cartilaginous rings extending
The document summarizes key aspects of respiratory physiology, including the four main functions of respiration, the mechanisms of pulmonary ventilation, gas exchange, and regulation of breathing. It describes the respiratory cycle of inspiration and expiration, how pressure gradients are established via changes in thoracic cavity size, and the roles of muscles like the diaphragm and intercostals. Pressure and volume changes during inhalation and exhalation are provided. Pulmonary volumes and capacities are defined, including vital capacity and functional residual capacity. Disorders like COPD and pulmonary fibrosis are also mentioned.
Lung volumes and capacities can be measured using spirometry to assess respiratory system efficiency and diagnose respiratory diseases. Key lung volumes include tidal volume, inspiratory reserve volume, expiratory reserve volume, residual volume. Lung capacities are combinations of volumes and include inspiratory capacity, functional residual capacity, vital capacity, and total lung capacity. Spirometry allows direct measurement of most volumes except residual volume, functional residual capacity, and total lung capacity, which require additional tests like helium dilution. Interpretation of spirometry results can distinguish between obstructive and restrictive lung diseases.
The document provides an overview of respiratory physiology, covering the basics of the respiratory system including its functional anatomy and the processes of ventilation, gas exchange, and gas transport. It discusses the respiratory system's key functions of gas exchange, pH regulation, and protection. The summary is:
The document outlines the basics of respiratory physiology, including the functional anatomy of the respiratory system and the processes of ventilation, gas exchange, and gas transport. It covers the respiratory tree, pleural membranes, muscles, and gas laws governing respiration. Key topics are the roles of inspiration, expiration, and alveolar ventilation in oxygen and carbon dioxide exchange via pressure gradients across the lungs.
1. The diaphragm and external intercostal muscles are the primary muscles of inspiration. Expiration is normally passive due to lung elasticity.
2. Lung compliance depends on factors like lung volume, blood volume, and disease processes. Surface tension forces from pulmonary surfactant reduce alveolar collapse.
3. Airway resistance arises from both laminar and turbulent gas flow. Increased resistance occurs from bronchospasm, secretions, and airway collapse related to low lung volume or forced exhalation.
The document discusses pulmonary function tests (PFTs) and their use in evaluating respiratory disorders. It provides details on various PFT measurements including spirometry tests like forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1). Obstructive disorders like asthma decrease FEV1 relative to FVC while restrictive disorders decrease both measurements. PFTs are used to diagnose lung conditions, assess severity, and monitor treatment effectiveness. They provide standardized measurements of respiratory function but must be interpreted along with other clinical information.
The document summarizes key aspects of the respiratory system in 3 paragraphs or less:
1) The respiratory system performs ventilation through breathing, gas exchange between air and blood in the lungs, and cellular respiration utilizing oxygen. Partial pressures and composition of gases change as air moves through the respiratory tract.
2) The conducting zone includes nasal passages and pharynx that warm and cleanse air before it reaches the lungs. The lungs contain alveoli with a large surface area for efficient gas exchange.
3) Breathing is regulated by brainstem centers that control the muscles of inspiration and expiration in response to chemoreceptors monitoring blood gas levels, maintaining homeostasis. Gases are transported via hemoglobin in red blood
This document provides an overview of respiratory physiology. Some key points:
- Gas exchange occurs through diffusion of oxygen from the alveoli into the blood and carbon dioxide from the blood into the alveoli down a partial pressure gradient.
- Fick's law describes how gas diffusion is proportional to surface area and inversely proportional to thickness. The adult lung has a large surface area of 85 square meters for gas exchange.
- Ventilation delivers gas to the alveoli through tidal volumes and respiratory rate. Alveolar ventilation is tidal volume minus dead space.
- Oxygen diffuses into the blood where it binds to hemoglobin. The oxygen-hemoglobin dissociation curve describes this relationship.
This document summarizes respiratory physiology, including the three functions of respiration: ventilation, gas exchange, and oxygen utilization. It describes the mechanics of breathing, the structure and function of the lungs and alveoli, gas exchange in the lungs and blood, and common pulmonary disorders like asthma and emphysema.
Gas exchange between the alveoli and the pulmonary capillary blood occurs by diffusion, as will be discussed in the next chapter. Diffusion of oxygen and carbon dioxide occurs passively, according to their concentration differences across the alveolar-capillary barrier. These concentration differences must be maintained by ventilation of the alveoli and perfusion of the pulmonary capillaries.
Alveolar ventilation brings oxygen into the lung and removes carbon dioxide from it. Similarly, the mixed venous blood brings carbon dioxide into the lung and takes up alveolar oxygen. The alveolar Image not available. and Image not available. are thus determined by the relationship between alveolar ventilation and pulmonary capillary perfusion. Alterations in the ratio of ventilation to perfusion, called the Image not available., will result in changes in the alveolar Image not available. and Image not available., as well as in gas delivery to or removal from the lung.
Alveolar ventilation is normally about 4 to 6 L/min and pulmonary blood flow (which is equal to cardiac output) has a similar range, and so the Image not available. for the whole lung is in the range of 0.8 to 1.2. Image not available. However, ventilation and perfusion must be matched on the alveolar-capillary level, and the Image not available. for the whole lung is really of interest only as an approximation of the situation in all the alveolar-capillary units of the lung. For instance, suppose that all 5 L/min of the cardiac output went to the left lung and all 5 L/min of alveolar ventilation went to the right lung. The whole lung Image not available. would be 1.0, but there would be no gas exchange because there could be no gas diffusion between the ventilated alveoli and the perfused pulmonary capillaries.
Oxygen is delivered to the alveolus by alveolar ventilation, is removed from the alveolus as it diffuses into the pulmonary capillary blood, and is carried away by blood flow. Similarly, carbon dioxide is delivered to the alveolus in the mixed venous blood and diffuses into the alveolus in the pulmonary capillary. The carbon dioxide is removed from the alveolus by alveolar ventilation. As will be discussed in Chapter 6, at resting cardiac outputs the diffusion of both oxygen and carbon dioxide is normally limited by pulmonary perfusion. Thus, the alveolar partial pressures of both oxygen and carbon dioxide are determined by the Image not available. If the Image not available. in an alveolar-capillary unit increases, the delivery of oxygen relative to its removal will increase, as will the removal ...
This document discusses oxygen transport and delivery in the body. It covers:
1. Oxygen is transported bound to hemoglobin (97%) and dissolved in plasma (3%). Oxygen diffuses from alveoli into plasma and binds to hemoglobin in red blood cells.
2. Arterial oxygen content is determined by dissolved oxygen and oxygen bound to hemoglobin. Normal arterial content is 20 ml O2/100ml blood. Venous content is normally 15 ml O2/100ml blood.
3. Oxygen delivery depends on cardiac output and arterial oxygen content. Normal delivery is 1000 ml O2/min. Oxygen uptake by tissues is normally 250 ml O2/min.
The document summarizes the physiology of the pulmonary circulatory system in three parts:
1) It describes the anatomy of the pulmonary vessels and pressures within the pulmonary system. The pulmonary artery branches into two main vessels with low pressure, distributing deoxygenated blood to the lungs.
2) It explains fluid dynamics within the lungs and how pulmonary edema develops if pressures rise above safety thresholds. The lungs maintain a negative interstitial pressure to prevent fluid buildup.
3) It covers fluid in the pleural cavity and how a negative pressure is needed to keep the lungs expanded via lymphatic drainage and fluid reabsorption. Pleural effusions can occur if drainage is blocked.
1. The pulmonary circulation receives the entire cardiac output from the right ventricle and has low pressure and resistance to accommodate large blood flow.
2. Pulmonary arteries are thin-walled and distensible to accommodate stroke volume, while capillaries are dense with anastomoses and veins act as reservoirs.
3. Pulmonary circulation acts as a filter to trap emboli and prevent them from reaching systemic circulation. Gas exchange occurs efficiently in the pulmonary capillaries through which blood passes in about 0.8 seconds.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
A presentation to the ASATT or American Society of Anesthesia Technicians and Technologists at the 2016 ASATT meeting in Chicago, IL was delivered by Kevin Lueders of Bell Medical and Corlius Birkill of Xavant Technologies of South Africa. This power point presentation discusses neuromuscular blocking agents history and usage. It also presented the various methods of monitoring NMBAs with traditional peripheral nerve stimulators and with the new quantitative or objective Train of Four, TOF monitor such as the Stimpod NMS 450 using accelerometry.
This document discusses the regulation of respiration through central and peripheral chemoreceptors. It covers:
1) The central control of breathing located in the medulla including the dorsal respiratory group (DRG), ventral respiratory group (VRG), apneustic center, and pneumotaxic center.
2) The central chemoreceptors (CCR) located in the medulla which are sensitive to changes in pH and CO2 levels in the cerebrospinal fluid and blood. Increased CO2 and decreased pH stimulate increased ventilation.
3) The peripheral chemoreceptors (PCR) located in the carotid bodies which are stimulated by decreased oxygen levels and increased CO2 and hydrogen ions. The PCR
Laplace's law describes the relationship between the transmural pressure difference across a blood vessel wall and the tension, radius, and thickness of the vessel wall. Specifically, the law states that the tension in the walls is equal to the pressure difference across the wall multiplied by the radius, divided by the thickness of the wall. An example given is dilated cardiomyopathy, where an increased heart radius requires greater wall tension to generate the same blood pressure during ejection. The law also explains why blowing up a balloon with a thicker wall requires more pressure difference to achieve the same wall tension.
Flowmeters influence of altitude and impact ofOfer Wellisch
The document discusses how altitude affects the accuracy of flowmeters and the impact of gas properties. It explains that as altitude increases, barometric pressure and partial pressure of oxygen decrease, requiring higher anesthetic concentrations to achieve the same drug effect. Vaporizers compensate slightly by delivering a higher percentage concentration at altitude to maintain a consistent partial pressure. However, desflurane vaporizers do not compensate and must be turned to higher settings with increasing altitude to offset the lower atmospheric pressure.
Diving Medicine & Decompression sicknessA Self Directed Learning Module For ...meducationdotnet
Applying Henry's Law helps explain decompression sickness in divers in the following ways:
- At high partial pressures of nitrogen during deep dives, large amounts of nitrogen dissolve in the blood and tissues according to Henry's Law.
- When ascending, the decreasing pressure causes nitrogen to come out of solution more quickly than it can be eliminated by the lungs if the rate of ascent is too fast.
- Nitrogen has a high solubility in tissues and blood, so large amounts can accumulate compared to oxygen during a dive. This makes it more likely to come out of solution and form bubbles during rapid ascents.
- Time is needed after deep dives to allow nitrogen to be safely eliminated from the tissues as the diver asc
CO2 is transported in the blood in four ways: dissolved, as carbonic acid, as bicarbonates, and as carbamino compounds. CO2 is produced during aerobic metabolism and must be transported to the lungs to be eliminated. It diffuses from tissues into blood and from blood into the alveoli due to partial pressure gradients. In the blood, CO2 is carried as bicarbonates through a chloride shift that maintains electrolyte balance. The CO2 dissociation curve shows the relationship between CO2 levels in blood and partial pressure of CO2. Haldane effect causes more CO2 to be released from blood into alveoli in the presence of oxygen. Hypercapnia occurs when arterial CO
This document discusses humidification and scavenging systems. It begins by defining humidification as a method to artificially condition gas for patient respiration. Two main humidifier types are described - passive humidifiers which rely on heat and moisture exchange, and active humidifiers which add water to gas. Key features and principles of operation are outlined for both passive and active humidifiers. Clinical signs of inadequate humidification and contraindications are also summarized.
Vaporizers are devices that change liquid anesthetic agents into vapor and add a controlled amount of vapor to the gas flow or breathing system. They do this by utilizing concepts like vapor pressure, boiling point, and partial pressure. There are several types of vaporizers including concentration calibrated vaporizers, measured flow vaporizers, and electronic vaporizers. Key factors that affect vaporization include temperature, flow rate, volatility of the agent, and carrier gas composition. Ambient pressure changes from high altitude, hyperbaric conditions, or back pressure can impact the vaporizer's output.
This document discusses neuromuscular blocking agents (NMBAs) and their reversal. It begins with a brief history of NMBA use in anesthesia. It then covers the mechanism of neuromuscular transmission and distinguishes between depolarizing and nondepolarizing NMBA mechanisms of action. The document classifies NMBAs and discusses their chemistry. It further explores the mechanisms of depolarizing and nondepolarizing NMBAs. Characteristics of depolarizing neuromuscular block are also summarized. The document provides detailed information on the structure and function of the neuromuscular junction.
Dr. T. Kumar presented on scavenging systems for removing trace levels of anesthetic gases in operating rooms. Scavenging systems use active or passive methods to collect and remove excess anesthetic gases through the room ventilation system. Proper scavenging can reduce ambient gas levels by up to 90%. Key components of scavenging systems include gas collection, transfer tubing, interfaces, disposal tubing, and disposal methods like central evacuation or room ventilation. Regular maintenance and equipment checks along with careful anesthesia techniques are needed to minimize waste gases and exposure risks for operating room staff.
This document summarizes key information about heme chemistry and hemoglobin. It discusses the structure and function of hemoglobin, including its role in oxygen transport and delivery to tissues. Hemoglobin is a protein composed of globin and heme groups that allows for the reversible binding and transport of oxygen in the blood. Factors like pH, carbon dioxide levels, and cooperativity between heme groups influence the oxygen binding affinity of hemoglobin.
1. Oxygen is transported from the lungs to tissues through a multi-step process involving diffusion, binding to hemoglobin, and active transport via blood circulation. (2) Oxygen diffuses from alveoli into pulmonary capillary blood where it binds to hemoglobin, becoming saturated at 98% in the lungs. (3) Oxygen is then transported to tissues where it dissociates from hemoglobin due to lower oxygen partial pressures, supplying oxygen for cellular respiration through diffusion into tissue fluid and cells.
The document summarizes key aspects of the respiratory system, including:
- External respiration involves gas exchange between the lungs and blood, transporting oxygen to tissues and carbon dioxide away. Internal respiration occurs via cellular respiration in mitochondria.
- The respiratory tract involves the nose, pharynx, larynx, trachea, bronchi and bronchioles leading to alveoli where gas exchange occurs by diffusion across pulmonary capillaries.
- Breathing is driven by changes in thoracic pressure and lung volumes via contraction of respiratory muscles and elastic recoil of the lungs and chest wall. Inspiration occurs as lungs fill a expanded chest cavity, expiration when it relaxes.
Red blood cells carry oxygen from the lungs to tissues throughout the body. They are adapted with a thick, thin shape to fit through capillaries, having a large surface area to absorb oxygen. Red blood cells lack a nucleus and organelles to make more room for hemoglobin, which is the protein that carries oxygen. White blood cells defend against diseases by ingesting bacteria and viruses and producing antibodies. Platelets allow blood to clot to stop bleeding and prevent bacteria from entering the body. Plasma is the straw-colored liquid component of blood that dissolves nutrients, waste products, hormones, antibodies and transports them between organs.
This document discusses vaporizers, which are devices used to convert liquid anesthetic agents into vapor for delivery to patients. It covers the basic principles of vaporization, factors that affect vaporizer output concentration, different types of vaporizers classified by their design and operating characteristics, and standards for vaporizer design. The key points are that vaporizers precisely regulate anesthetic vapor concentrations, multiple factors influence output, and designs vary in things like temperature compensation, agent specificity, and positioning within the breathing circuit.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help boost mental well-being.
The document summarizes the structure and function of the lungs. It describes that the lungs are part of the respiratory system and are responsible for bringing oxygen into the body and removing carbon dioxide. The lungs contain bronchi, bronchioles, and alveoli where gas exchange occurs. Various lung diseases and conditions are also outlined such as lung cancer, silicosis, asthma, pneumonia and COPD. Tips for maintaining healthy lungs include not smoking, exercise, and a healthy diet.
This document provides an overview of the anatomy and physiology of the respiratory system. It describes the main structures involved in respiration including the nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, lungs, and respiratory muscles. It explains the processes of gas exchange that occur in the alveoli and pulmonary capillaries. It also discusses concepts such as dead space, surfactant, pleural pressure, alveolar pressure, transpulmonary pressure, compliance, and spirometry.
The trachea is a cartilaginous tube that extends from the larynx to the lungs. It divides at the carina into the right and left main bronchi. The right bronchus is wider, shorter and more vertical, while the left is smaller but longer. The bronchi continue dividing within the lungs to form the bronchial tree which supplies the lungs. Each lung has a root, hilum, lobes, borders and surfaces. The lungs are supplied by the pulmonary arteries and veins and are innervated by the pulmonary plexus.
This document provides an overview of respiratory anatomy and physiology. It discusses the three functions of respiration: ventilation, gas exchange, and oxygen utilization. Key topics covered include the mechanics of breathing, the structure and function of the lungs and alveoli, gas exchange, pulmonary circulation, and control of breathing via brain stem centers. Pulmonary function tests and common respiratory disorders are also summarized.
This document summarizes key concepts of respiratory physiology. It discusses the three functions of respiration: ventilation, gas exchange in the lungs and tissues, and oxygen utilization through cellular respiration. It describes the mechanics of breathing including intrapulmonary and intrapleural pressures. Gas exchange occurs by diffusion down concentration gradients between air in the alveoli and blood in the pulmonary capillaries. Oxygen diffuses into the blood and carbon dioxide diffuses out.
The document discusses respiratory physiology, including:
1. Gas exchange occurs between air and capillaries in the lungs and between systemic capillaries and tissues, maintaining oxygen and carbon dioxide levels.
2. The lungs contain over 300 million alveoli that have a large surface area for gas exchange. Each alveolus is lined by a single cell layer for efficient diffusion.
3. Respiration includes ventilation (breathing), gas exchange, and oxygen utilization in cellular respiration. Ventilation is driven by pressure differences induced by changes in lung volume during inspiration and expiration.
The document summarizes key aspects of respiratory system anatomy and physiology. It describes the main functions of the respiratory system as taking in oxygen and giving out carbon dioxide, while also regulating acid-base balance, heat, phonation, and vocalization. Anatomically, the respiratory system is divided into intrathoracic and extrathoracic parts, with the intrathoracic part involving structures like the trachea, bronchi, bronchioles, alveoli and lungs where gas exchange occurs. Physiologically, the system is divided into conductive and respiratory zones. Other topics covered include pulmonary volumes and capacities, ventilation, forces controlling lung volumes like pleural pressure and surface tension, diffusion of gases, and work of breathing
This document discusses respiratory function and its importance to anesthesia. It covers topics like cellular respiration, aerobic vs anaerobic respiration, muscles of respiration, mechanisms of ventilation, lung volumes, compliance, and factors that affect respiration. The speaker is Dr. Tipu and the event is being coordinated by Dr. Shivali Pandey.
Respiration includes ventilation, gas exchange, and tissue utilization of oxygen. Ventilation involves breathing, while gas exchange occurs in the lungs and tissues. The respiratory system consists of a conducting zone that transports air, and an exchanging zone in the lungs. Gas exchange relies on pressure gradients and diffusion across thin membranes. Key functions and structures include the nasal cavity, trachea, bronchi, bronchioles, lungs, diaphragm and intercostal muscles, and alveoli.
The respiratory system functions to oxygenate tissues and remove carbon dioxide through gas exchange. It consists of the upper respiratory tract including the nose and pharynx, and the lower respiratory tract including the larynx, trachea, bronchi, bronchioles and alveoli in the lungs. Oxygen diffuses into the blood in the alveoli while carbon dioxide diffuses out. Breathing is controlled by respiratory centers in the brain and involves inspiration through contraction of the diaphragm and expiration through relaxation.
Breathing and Exchange of Gases Class 11thNehaRohtagi1
Created By: NehaRohtagi1
Class 11th CBSE [NCERT]
Biology Chapter 17
Notes on the topic: Breathing and Exchange of Gases
For Class - 11th
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This document provides an overview of respiratory physiology and acute respiratory failure. It discusses:
1. The functions of the respiratory system including gas exchange, acid-base balance, phonation, pulmonary defense, and metabolism.
2. The three components of respiration - ventilation, gas exchange, and oxygen utilization. It describes the mechanics of ventilation and gas exchange via diffusion.
3. The conducting and respiratory zones of the lungs and structures involved in gas exchange like alveoli and surfactant.
4. Control of respiration via brainstem centers that regulate rhythmic breathing and chemoreceptors that sense blood gases and pH to modulate breathing rate and depth.
This document provides an overview of respiratory physiology and acute respiratory failure. It discusses:
1. The functions of the respiratory system including gas exchange, acid-base balance, phonation, pulmonary defense, and metabolism.
2. The three components of respiration - ventilation, gas exchange, and oxygen utilization. It describes the mechanics of ventilation and gas exchange via diffusion.
3. The conducting and respiratory zones of the lungs and structures involved in gas exchange like alveoli and surfactant.
4. Control of respiration via brainstem centers that regulate breathing rhythm and respond to chemoreceptors monitoring blood gases.
This document provides an overview of respiratory physiology and acute respiratory failure. It discusses the functions of the respiratory system including gas exchange, acid-base balance, and pulmonary defense. The three components of respiration - ventilation, gas exchange, and oxygen utilization - are defined. Key concepts around ventilation, the conducting and respiratory zones, alveoli, pulmonary circulation, innervation, and thoracic cavity pressures are summarized. Factors that influence lung compliance, elasticity, and surface tension are also reviewed.
This document provides an overview of respiratory physiology and acute respiratory failure. It discusses the functions of the respiratory system including gas exchange, acid-base balance, and pulmonary defense. The three components of respiration - ventilation, gas exchange, and oxygen utilization - are defined. Key concepts around ventilation, the conducting and respiratory zones, alveoli, pulmonary circulation, innervation, and thoracic cavity pressures are summarized. Factors that influence lung compliance, elasticity, and surface tension are also reviewed.
The document describes the structure and function of the respiratory system. It details the major components including the nasal passages, pharynx, larynx, trachea, bronchi, bronchioles, respiratory bronchioles, alveolar ducts, and alveoli. It explains how air moves through the respiratory tree from the trachea down to the alveoli where gas exchange occurs. It also discusses cellular respiration and the role of oxygen and carbon dioxide exchange between the alveoli and blood in the pulmonary capillaries. Finally, it covers the mechanics of ventilation including atmospheric pressure, intra-alveolar pressure, intra-pleural pressure, and the importance of transmural pressure gradients.
The document discusses the human respiratory system and the process of breathing. It begins by explaining that oxygen is used by organisms to break down nutrients like glucose, producing carbon dioxide as a waste product. It then describes the main parts of the human respiratory system, including the nostrils, pharynx, larynx, trachea, bronchi, bronchioles and alveoli in the lungs. It explains that breathing involves the exchange of oxygen and carbon dioxide between the alveoli and blood, and the transport of these gases by blood to and from tissues through diffusion and concentration gradients.
This document provides an overview of respiratory physiology, including:
1) The structures and functions of the conducting and respiratory zones of the lungs. Gas exchange occurs between air and blood in the alveoli.
2) The mechanics of breathing, including the roles of the diaphragm, intercostal muscles, and pleural membranes in inspiration and expiration.
3) Measurements of pulmonary function including lung volumes and capacities. Pulmonary disorders can be restrictive or obstructive.
This document provides an overview of respiration and respiratory mechanics. It defines internal and external respiration, describes the four steps of external respiration, and explains the mechanics of ventilation - the first step involving gas exchange between the atmosphere and the lungs. Inspiration is an active process relying on muscle contraction, while normal expiration is usually passive. Factors such as lung volumes, airway resistance, compliance, and work of breathing are also discussed.
The document summarizes the mechanics of pulmonary ventilation. It describes how the diaphragm and intercostal muscles work together during inhalation and exhalation to expand and contract the lungs and chest cavity. During inhalation, contraction of the diaphragm and external intercostal muscles increases the thoracic volume, drawing air into the lungs. During exhalation, relaxation of these muscles decreases thoracic volume and passively pushes air from the lungs. The roles of surface tension and pulmonary surfactant in preventing alveolar collapse are also discussed.
The document summarizes key aspects of the respiratory system including:
1. The three major steps of respiration: pulmonary ventilation, external respiration, and internal respiration.
2. The major organs of the respiratory system including the nose, pharynx, larynx, trachea, bronchi, lungs, and alveoli.
3. The processes of breathing including inhaling via the diaphragm and intercostal muscles and exhaling via relaxation of these muscles.
Respiratory physiology is a branch of physiology that studies the mechanics, chemistry, and control of respiration. Respiration is the process by which an organism exchanges gases with its environment. In humans, respiration is the process by which we take in oxygen from the air and release carbon dioxide back into the air.
The mechanics of respiration are the processes by which air is moved into and out of the lungs. This is done by the muscles of the respiratory system, which include the diaphragm, the intercostal muscles, and the muscles of the larynx. The details of how the respiratory system carries out its functions are covered in this course.
The main objective of this course is that readers should:
1. Know the meaning of respiration
2. Be able to explain how the intrapulmonary and intrapleural pressures vary during ventilation and relate these pressure changes to Boyle's law.
3. Be able to define the terms compliance and elasticity and explain how these lung properties affect ventilation.
4. Be able to discuss the significance of surface tension in lung mechanics, explain how the law of Laplace applies to lung function, and describe the role of pulmonary surfactant.
5. Be able to know the pulmonary function tests and their importance. e.t.c.
The document discusses respiratory physiology and the respiratory system. It covers several key concepts:
1. It describes Dalton's Law of Partial Pressures and how total gas pressure equals the sum of partial pressures of individual gases.
2. It explains the mechanics of breathing including the roles of the diaphragm and rib cage. Inspiration is an active process requiring work.
3. It discusses the lungs and alveoli where gas exchange occurs between the blood in pulmonary capillaries and air in alveoli. Surfactant reduces surface tension in the alveoli to prevent their collapse.
4. Several gas laws related to respiration are also covered such as Boyle's Law, Charles' Law,
The umbilical cord connects the fetus to the placenta and measures approximately 50 cm in length and 2 cm in diameter at term. It contains one vein that carries oxygenated blood to the fetus and two arteries that carry deoxygenated blood away. The cord inserts into the placenta near its center in most cases. Abnormalities can include abnormal insertion points, short or long length, knots, torsion, hematoma, or having a single umbilical artery instead of two.
The placenta develops from fetal and maternal tissues to function as the respiratory, nutritive, excretory, barrier and endocrine organ of pregnancy. It transfers oxygen, nutrients and waste between the mother and fetus. The placenta can develop abnormalities in its shape, size, position or adhesion to the uterine wall which may cause complications like preterm birth or hemorrhage. Placental lesions like infarcts may also occur due to conditions like hypertension.
The document discusses the fetal membranes, which include the chorion and amnion. The chorion is the outer membrane that is attached to the placenta and uterine wall. The amnion lines the chorion and encloses the fetus and amniotic fluid. The amniotic fluid provides protection and nutrition for the fetus, and aids in temperature regulation and movement. It is composed primarily of water, carbohydrates, proteins and minerals. The amniotic fluid circulates continuously, with production from the fetal membranes, fetal urine and transudation from maternal and fetal blood.
The document summarizes the key stages in human reproduction from fertilization through early pregnancy development. It describes how sperm mature and are capacitated in the female reproductive tract. Upon ovulation, sperm meet and fertilize the ovum in the fallopian tubes. The zygote then undergoes cell division and develops into a blastocyst that implants in the uterus. The trophoblast cells of the blastocyst invade the uterine lining and develop into a placenta to exchange nutrients and waste with the mother's blood. Major developmental milestones in early pregnancy include chorion, amnion and decidua formation.
The document discusses several minor complaints that may occur during pregnancy, including gingivitis, ptyalism, heartburn, constipation, hemorrhoids, varicosities, dyspnea, urinary symptoms, leucorrhea, leg cramps, paraethesia, and backache. For each complaint, the causes and recommended treatments are provided.
This document discusses the diagnosis of pregnancy over three trimesters. In the first trimester, common symptoms include missed periods, morning sickness, frequent urination, and breast changes. Signs include enlarged, soft breasts and uterus, and a softer, purplish cervix. Pregnancy tests detect human chorionic gonadotropin in urine or blood. Ultrasounds can visualize the gestational sac after 4-5 weeks. In the second trimester, symptoms decrease while the abdomen enlarges and fetal movement is felt. Signs include skin changes and palpable fetal parts. The third trimester confirms pregnancy through palpation of fetal parts and auscultation of the fetal heart.
Antenatal care involves regular checkups during pregnancy to monitor the health of the mother and baby. Checkups include exams, tests, and education on nutrition, exercise, hygiene, warning signs and avoiding risks. The goals are to prevent or treat complications, detect issues, and ensure healthy development. Women receive more frequent exams as their due date approaches, and are instructed on a nutritious diet, moderate exercise, adequate rest, hygienic practices, and when to seek medical help if problems arise.
The document discusses postpartum mood disorders, including prevalence, risk factors, screening tools, diagnosis, and treatment options. It notes that postpartum mood disorders range from mild and temporary postpartum blues to more severe postpartum depression and postpartum psychosis. Screening tools like the Edinburgh Postnatal Depression Scale can help identify at-risk women. Treatment involves psychosocial therapies and may include antidepressant medication depending on severity. A multidisciplinary approach is important to address biological, psychological and social factors.
Uterine fibroids are benign smooth muscle tumors that develop in the uterus. They are the most common solid pelvic tumors, affecting 20-25% of women during their reproductive years. Fibroids can vary in size and location, and may cause heavy menstrual bleeding, pelvic pressure or pain. Treatment options include observation, medical therapy to reduce estrogen levels, or surgical removal of fibroids.
Version refers to changing the fetal lie or position in the uterus. There are three main types: external cephalic version, internal podalic version, and bipolar podalic version. External cephalic version involves manipulating the fetus externally to convert a breech presentation to head-first. Internal podalic version is performed under anesthesia when the cervix is fully dilated to grasp the fetus's feet and convert a transverse lie to breech. Bipolar podalic version uses both internal and external manipulation through a partially dilated cervix for special circumstances. Complications can include fetal distress, premature separation of the placenta, and maternal hemorrhage.
Vacuum extraction is a method to assist in childbirth using suction from a cup placed on the baby's head to help with traction during contractions. There are different types of cups including metal, soft, and bird's cups. Vacuum extraction is indicated when forceps cannot be used and has advantages over forceps like less need for anesthesia and less compression force applied. Complications can include maternal lacerations and cervical injuries or fetal issues like cephalhematomas and scalp lacerations.
Symphysiotomy is a surgical procedure that divides the symphysis pubis bone to widen the pelvis during childbirth. It is indicated when cephalopelvic disproportion makes vaginal delivery difficult or dangerous but cesarean section is not available or advised. The procedure involves making a small incision above the pubic bone and gradually separating the joint using a scalpel. Complications can include bleeding, injury to nearby organs, infection, and long-term issues like incontinence or an unstable pelvis.
This document discusses obstetric forceps, which are metal instruments used to extract a baby's head during delivery. It describes different types of forceps and their proper application techniques. Forceps are indicated for prolonged second stage of labor, maternal distress, or fetal distress. Correct application involves inserting one blade along each side of the baby's head. Potential complications include laceration, hemorrhage, nerve injury, or problems for the baby such as skull fractures. Failure to deliver with forceps may require removal and assessment to determine if cesarean section is needed.
This document discusses episiotomy, which is an incision made in the perineum during childbirth to widen the vaginal opening. It can help prevent tearing and complications. The two main types are median and mediolateral episiotomies. Median episiotomies involve a midline incision while mediolateral incisions extend laterally towards the ischial tuberosity. Episiotomies are usually performed when the vaginal opening is distended during crowning to prevent stretching injuries. They are sutured closed after delivery.
The document discusses Caesarean section, including indications, types, procedure, complications, and mode of delivery in subsequent pregnancies. A Caesarean section is a surgical procedure to deliver one or more babies through incisions in the abdomen and uterus. The rate of Caesarean sections has increased from 5% in 1970 to 25% in 1990 due to factors such as abandoning difficult procedures in favor of C-sections and increased use for breech births. Complications can include hemorrhage, infections, and injuries to the mother or baby.
Normal labour involves the spontaneous expulsion of a single, mature fetus through the birth canal within 3-18 hours without complications. It occurs when hormonal and mechanical factors cause the cervix to efface and dilate in stages from 3cm to full 10cm dilation. Labour proceeds through four stages: 1) cervical dilation, 2) expulsion of the fetus, 3) expulsion of the placenta, and 4) recovery. The fetus descends through the birth canal with increased flexion to facilitate delivery of the head.
The fetal skull consists of three parts: the vault, face, and base. The vault is made up of the frontal, parietal, and occipital bones which are separated by sutures. The face extends from the chin to the nose. Fontanelles are soft spots located where sutures meet which are important for assessing fetal position and flexion. The skull has various longitudinal and transverse diameters used to determine which will engage and pass through the birth canal during delivery.
The female pelvis is divided into the false pelvis and true pelvis. The true pelvis is further divided into the pelvic inlet, cavity, and outlet. The document describes the boundaries and diameters of each region including the anatomical transverse diameter of 13cm at the inlet. It also discusses the pelvic planes and axes, and the Caldwell-Moloy classification of pelvic types including the gynaecoid, anthropoid, android, and platypelloid pelvis.
This document outlines the active management of normal labour in 4 stages: antenatal preparation, first stage (history, exam, procedures), second stage (delivery of baby), third stage (delivery of placenta), and fourth stage (postpartum care of mother and baby). The goal is a healthy delivery with minimal effects. Key procedures include monitoring contractions/fetal heart with a partogram, positioning, nutrition, analgesia, perineal support, and immediate newborn care.
Thyrotoxicosis in pregnancy can cause complications like abortion and preterm labour. Clinical features include weight loss, heat intolerance, tremors, and fast heart rate. It is treated with antithyroid drugs like propylthiouracil or carbimazole. Epilepsy in pregnancy commonly presents as grand mal seizures, which are treated with phenobarbitone or phenytoin along with folic acid. Rhesus isoimmunization occurs when an Rh-negative mother develops antibodies against Rh-positive blood from her baby. It can be prevented by giving the mother anti-D immunoglobulin after delivery or pregnancy events involving blood transfer from baby to mother. Affected babies may require monitoring, phot
2. Respiration
The term respiration includes 3
separate functions:
Ventilation:
Breathing.
Gas exchange:
Between air and capillaries in the lungs.
Between systemic capillaries and tissues of the
body.
02 utilization:
Cellular respiration.
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3. Ventilation
Mechanical process that moves
air in and out of the lungs.
[O2] of air is higher in the lungs Insert 16.1
than in the blood, O2 diffuses
from air to the blood.
C02 moves from the blood to
the air by diffusing down its
concentration gradient.
Gas exchange occurs entirely
by diffusion:
Diffusion is rapid because of
the large surface area and the
small diffusion distance.
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4. Alveoli
Polyhedral in shape and clustered like
units of honeycomb.
~ 300 million air sacs (alveoli).
Large surface area (60–80 m2).
Each alveolus is 1 cell layer thick.
Total air barrier is 2 cells across (2 m).
2 types of cells:
Alveolar type I:
Structural cells.
Alveolar type II:
Secrete surfactant.
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5. Respiratory Zone
Region of
gas
exchange
between air
and blood.
Includes
respiratory
bronchioles
and alveolar
sacs.
Must contain
alveoli.
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6. Conducting Zone
All the structures air
passes through before
reaching the Insert fig. 16.5
respiratory zone.
Warms and humidifies
inspired air.
Filters and cleans:
Mucus secreted to trap
particles in the inspired
air.
Mucus moved by cilia to
be expectorated.
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7. Thoracic Cavity
Diaphragm:
Sheets of striated muscle divides anterior body
cavity into 2 parts.
Above diaphragm: thoracic cavity:
Contains heart, large blood vessels, trachea,
esophagus, thymus, and lungs.
Below diaphragm: abdominopelvic cavity:
Contains liver, pancreas, GI tract, spleen, and
genitourinary tract.
Intrapleural space:
Space between visceral and parietal pleurae.
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8. Intrapulmonary and Intrapleural
Pressures
Visceral and parietal pleurae are flush against each
other.
The intrapleural space contains only a film of fluid secreted
by the membranes.
Lungs normally remain in contact with the chest
walls.
Lungs expand and contract along with the thoracic
cavity.
Intrapulmonary pressure:
Intra-alveolar pressure (pressure in the alveoli).
Intrapleural pressure:
Pressure in the intrapleural space.
Pressure is negative, due to lack of air in the intrapleural
space.
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9. Transpulmonary Pressure
Pressure difference across the wall of
the lung.
Intrapulmonary pressure – intrapleural
pressure.
Keeps the lungs against the chest wall.
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10. Intrapulmonary and Intrapleural
Pressures (continued)
During inspiration:
Atmospheric pressure is > intrapulmonary
pressure (-3 mm Hg).
During expiration:
Intrapulmonary pressure (+3 mm Hg) is >
atmospheric pressure.
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11. Boyle’s Law
Changes in intrapulmonary pressure occur as
a result of changes in lung volume.
Pressure of gas is inversely proportional to its
volume.
Increase in lung volume decreases
intrapulmonary pressure.
Air goes in.
Decrease in lung volume, raises
intrapulmonary pressure above atmosphere.
Air goes out.
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12. Physical Properties of the Lungs
Ventilation occurs as a result of
pressure differences induced by
changes in lung volume.
Physical properties that affect lung
function:
Compliance.
Elasticity.
Surface tension.
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13. Compliance
Distensibility (stretchability):
Ease with which the lungs can expand.
Change in lung volume per change in
transpulmonary pressure.
V/ P
100 x more distensible than a balloon.
Compliance is reduced by factors that
produce resistance to distension.
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14. Elasticity
Tendency to return to initial size after
distension.
High content of elastin proteins.
Very elastic and resist distension.
Recoil ability.
Elastic tension increases during
inspiration and is reduced by recoil
during expiration.
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15. Surface Tension
Force exerted by fluid in alveoli to resist
distension.
Lungs secrete and absorb fluid, leaving a very thin film of
fluid.
This film of fluid causes surface tension.
Fluid absorption is driven (osmosis) by Na+ active
transport.
Fluid secretion is driven by the active transport of
Cl- out of the alveolar epithelial cells.
H20 molecules at the surface are attracted to
other H20 molecules by attractive forces.
Force is directed inward, raising pressure in
alveoli.
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16. Surface Tension (continued)
Law of Laplace:
Pressure in alveoli is Insert fig. 16.11
directly proportional to
surface tension; and
inversely proportional to
radius of alveoli.
Pressure in smaller
alveolus would be greater
than in larger alveolus, if
surface tension were the
same in both.
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17. Surfactant
Phospholipid produced
by alveolar type II cells.
Insert fig. 16.12
Lowers surface tension.
Reduces attractive forces
of hydrogen bonding by
becoming interspersed
between H20 molecules.
Surface tension in
alveoli is reduced.
As alveoli radius
decreases, surfactant’s
ability to lower surface
tension increases.
Disorders:
RDS.
ARDS. www.freelivedoctor.com
18. Quiet Inspiration
Active process:
Contraction of diaphragm, increases thoracic
volume vertically.
Parasternal and external intercostals contract,
raising the ribs; increasing thoracic volume
laterally.
Pressure changes:
Alveolar changes from 0 to –3 mm Hg.
Intrapleural changes from –4 to –6 mm Hg.
Transpulmonary pressure = +3 mm Hg.
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19. Expiration
Quiet expiration is a passive process.
After being stretched by contractions of the diaphragm
and thoracic muscles; the diaphragm, thoracic muscles,
thorax, and lungs recoil.
Decrease in lung volume raises the pressure within alveoli
above atmosphere, and pushes air out.
Pressure changes:
Intrapulmonary pressure changes from –3 to +3 mm Hg.
Intrapleural pressure changes from –6 to –3 mm Hg.
Transpulmonary pressure = +6 mm Hg.
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21. Pulmonary Function Tests
Assessed by spirometry.
Subject breathes into a closed system in which air is
trapped within a bell floating in H20.
The bell moves up when the subject exhales and
down when the subject inhales.
Insert fig. 16.16
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22. Terms Used to Describe Lung Volumes
and Capacities
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23. Anatomical Dead Space
Not all of the inspired air reached the
alveoli.
As fresh air is inhaled it is mixed with air in
anatomical dead space.
Conducting zone and alveoli where [02] is lower
than normal and [C02] is higher than normal.
Alveolar ventilation = F x (TV- DS).
F = frequency (breaths/min.).
TV = tidal volume.
DS = dead space.
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24. Restrictive and Obstructive
Disorders
Restrictive
disorder:
Vital capacity is
reduced. Insert fig. 16.17
FVC is normal.
Obstructive
disorder:
Diagnosed by tests
that measure the
rate of expiration.
VC is normal.
FEV1 is < 80%.
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25. Pulmonary Disorders
Dyspnea:
Shortness of breath.
COPD (chronic obstructive pulmonary
disease):
Asthma:
Obstructive air flow through bronchioles.
Caused by inflammation and mucus secretion.
Inflammation contributes to increased airway
responsiveness to agents that promote bronchial
constriction.
IgE, exercise.
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26. Pulmonary Disorders (continued)
Emphysema:
Alveolar tissue is destroyed.
Chronic progressive condition that reduces surface area for
gas exchange.
Decreases ability of bronchioles to remain open during
expiration.
Cigarette smoking stimulates macrophages and
leukocytes to secrete protein digesting enzymes that
destroy tissue.
Pulmonary fibrosis:
Normal structure of lungs disrupted by accumulation
of fibrous connective tissue proteins.
Anthracosis.
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27. Gas Exchange in the Lungs
Dalton’s Law:
Total pressure of a gas mixture is = to the sum
of the pressures that each gas in the mixture
would exert independently.
Partial pressure:
The pressure that an particular gas exerts
independently.
PATM = PN2 + P02 + PC02 + PH20= 760 mm Hg.
02 is humidified = 105 mm Hg.
H20 contributes to partial pressure (47 mm Hg).
P02 (sea level) = 150 mm Hg.
PC0 = 40 mm Hg.
2
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28. Partial Pressures of Gases in
Inspired Air and Alveolar Air
Insert fig. 16.20
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29. Partial Pressures of Gases in
Blood
When a liquid or gas (blood and alveolar air)
are at equilibrium:
The amount of gas dissolved in fluid reaches a
maximum value (Henry’s Law).
Depends upon:
Solubility of gas in the fluid.
Temperature of the fluid.
Partial pressure of the gas.
[Gas] dissolved in a fluid depends directly on
its partial pressure in the gas mixture.
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30. Significance of Blood P0 and PC0 2 2
Measurements
At normal
P0 arterial
2
blood is
about 100
mm Hg.
P0 level in
2
the systemic
veins is
about 40
mm Hg.
P is 46 mm Hg in the systemic veins.
C02
Provides a good index of lung function.
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31. Pulmonary Circulation
Rate of blood flow through the pulmonary
circulation is = flow rate through the systemic
circulation.
Driving pressure is about 10 mm Hg.
Pulmonary vascular resistance is low.
Low pressure pathway produces less net filtration
than produced in the systemic capillaries.
Avoids pulmonary edema.
Autoregulation:
Pulmonary arterioles constrict when alveolar P0 2
decreases.
Matches ventilation/perfusion ratio.
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32. Pulmonary Circulation (continued)
In a fetus:
Pulmonary circulation has a higher vascular
resistance, because the lungs are partially
collapsed.
After birth, vascular resistance decreases:
Opening the vessels as a result of subatmospheric
intrapulmonary pressure.
Physical stretching of the lungs.
Dilation of pulmonary arterioles in response to
increased alveolar P0 .2
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33. Lung Ventilation/Perfusion
Ratios
Functionally:
Insert fig. 16.24
Alveoli at
apex are
underperfused
(overventilated).
Alveoli at the base
are underventilated
(overperfused).
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34. Disorders Caused by High Partial
Pressures of Gases
Nitrogen narcosis:
At sea level nitrogen is physiologically inert.
Under hyperbaric conditions:
Nitrogen dissolves slowly.
Can have deleterious effects.
Resembles alcohol intoxication.
Decompression sickness:
Amount of nitrogen dissolved in blood as a diver
ascends decreases due to a decrease in PN . 2
If occurs rapidly, bubbles of nitrogen gas can form in
tissues and enter the blood.
Block small blood vessels producing the “bends.”
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35. Brain Stem Respiratory Centers
Neurons in the
reticular formation of
the medulla Insert fig. 16.25
oblongata form the
rhythmicity center:
Controls automatic
breathing.
Consists of interacting
neurons that fire
either during
inspiration (I neurons)
or expiration
(E neurons).
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36. Brain Stem Respiratory Centers
(continued)
I neurons project to, and stimulate
spinal motor neurons that innervate
respiratory muscles.
Expiration is a passive process that
occurs when the I neurons are
inhibited.
Activity varies in a reciprocal way.
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37. Rhythmicity Center
I neurons located primarily in dorsal respiratory
group (DRG):
Regulate activity of phrenic nerve.
Project to and stimulate spinal interneurons that
innervate respiratory muscles.
E neurons located in ventral respiratory group
(VRG):
Passive process.
Controls motor neurons to the internal intercostal
muscles.
Activity of E neurons inhibit I neurons.
Rhythmicity of I and E neurons may be due to
pacemaker neurons.
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38. Pons Respiratory Centers
Activities of medullary rhythmicity center
is influenced by pons.
Apneustic center:
Promotes inspiration by stimulating the I
neurons in the medulla.
Pneumotaxic center:
Antagonizes the apneustic center.
Inhibits inspiration.
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39. Chemoreceptors
2 groups of chemo-
receptors that monitor
changes in blood PC0 , 2
P0 , and pH.
2
Insert fig. 16.27
Central:
Medulla.
Peripheral:
Carotid and aortic
bodies.
Control breathing
indirectly via sensory
nerve fibers to the
medulla (X, IX).
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40. Effects of Blood PC0 and pH on 2
Ventilation
Chemoreceptor input modifies the rate and
depth of breathing.
Oxygen content of blood decreases more slowly
because of the large “reservoir” of oxygen
attached to hemoglobin.
Chemoreceptors are more sensitive to changes in
PC0 .
2
H20 + C02 H2C03 H+ + HC03-
Rate and depth of ventilation adjusted to
maintain arterial PC0 of 40 mm Hg.
2
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41. Chemoreceptor Control
Central chemoreceptors:
More sensitive to changes in arterial PC0 . 2
H20 + C02 H2C03 H+
H+ cannot cross the blood brain barrier.
C02 can cross the blood brain barrier and
will form H2C03.
Lowers pH of CSF.
Directly stimulates central chemoreceptors.
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42. Chemoreceptor Control (continued)
Peripheral chemoreceptors:
Are not stimulated directly by changes in
arterial PC0 .
2
H20 + C02 H2C03 H+
Stimulated by rise in [H+] of arterial
blood.
Increased [H+] stimulates peripheral
chemoreceptors.
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44. Effects of Blood P0 on 2
Ventilation
Blood P0 affected by breathing indirectly.
2
Influences chemoreceptor sensitivity to changes in
PC0 .
2
Hypoxic drive:
Emphysema blunts the chemoreceptor response to
PC0 .
2
Choroid plexus secrete more HC03- into CSF, buffering
the fall in CSF pH.
Abnormally high PC0 enhances sensitivity of carotid
2
bodies to fall in P0 .
2
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45. Effects of Pulmonary Receptors
on Ventilation
Lungs contain receptors that influence the brain
stem respiratory control centers via sensory fibers
in vagus.
Unmyelinated C fibers can be stimulated by:
Capsaicin:
Produces apnea followed by rapid, shallow breathing.
Histamine and bradykinin:
Released in response to noxious agents.
Irritant receptors are rapidly adaptive receptors.
Hering-Breuer reflex:
Pulmonary stretch receptors activated during inspiration.
Inhibits respiratory centers to prevent undue tension on lungs.
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46. Hemoglobin and 02 Transport
280 million
hemoglobin/RBC.
Each hemoglobin Insert fig. 16.32
has 4 polypeptide
chains and 4
hemes.
In the center of
each heme group
is 1 atom of iron
that can combine
with 1 molecule
02.
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47. Hemoglobin
Oxyhemoglobin:
Normal heme contains iron in the reduced form
(Fe2+).
Fe2+ shares electrons and bonds with oxygen.
Deoxyhemoglobin:
When oxyhemoglobin dissociates to release
oxygen, the heme iron is still in the reduced form.
Hemoglobin does not lose an electron when it
combines with 02.
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48. Hemoglobin (continued)
Methemoglobin:
Has iron in the oxidized form (Fe3+).
Lacks electrons and cannot bind with 02.
Blood normally contains a small amount.
Carboxyhemoglobin:
The reduced heme is combined with
carbon monoxide.
The bond with carbon monoxide is 210
times stronger than the bond with oxygen.
Transport of 02 to tissues is impaired.
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49. Hemoglobin (continued)
Oxygen-carrying capacity of blood determined by
its [hemoglobin].
Anemia:
[Hemoglobin] below normal.
Polycythemia:
[Hemoglobin] above normal.
Hemoglobin production controlled by erythropoietin.
Production stimulated by PC0 delivery to kidneys.
2
Loading/unloading depends:
P0 of environment.
2
Affinity between hemoglobin and 02.
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50. Oxyhemoglobin Dissociation
Curve
Graphic illustration of the % oxyhemoglobin
saturation at different values of P0 . 2
Loading and unloading of 02.
Steep portion of the sigmoidal curve, small changes in P0
2
produce large differences in % saturation (unload more 02).
Decreased pH, increased temperature, and
increased 2,3 DPG:
Affinity of hemoglobin for 02 decreases.
Greater unloading of 02:
Shift to the curve to the right.
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52. Effects of pH and Temperature
The loading and
unloading of O2
influenced by the
affinity of Insert fig. 16.35
hemoglobin for 02.
Affinity is
decreased when
pH is decreased.
Increased
temperature and
2,3-DPG:
Shift the curve to
the right.
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53. Effect of 2,3 DPG on 02 Transport
Anemia:
RBCs total blood [hemoglobin] falls, each
RBC produces greater amount of 2,3 DPG.
Since RBCs lack both nuclei and mitochondria,
produce ATP through anaerobic metabolism.
Fetal hemoglobin (hemoglobin f):
Has 2 -chains in place of the -chains.
Hemoglobin f cannot bind to 2,3 DPG.
Has a higher affinity for 02.
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54. Inherited Defects in Hemoglobin
Structure and Function
Sickle-cell anemia:
Hemoglobin S differs in that valine is substituted
for glutamic acid on position 6 of the chains.
Cross links form a “paracrystalline gel” within the RBCs.
Makes the RBCs less flexible and more fragile.
Thalassemia:
Decreased synthesis of or chains, increased
synthesis of chains.
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55. Muscle Myoglobin
Red pigment found
exclusively in striated
muscle.
Insert fig. 13.37
Slow-twitch skeletal
fibers and cardiac
muscle cells are rich in
myoglobin.
Have a higher affinity
for 02 than hemoglobin.
May act as a “go-
between” in the transfer
of 02 from blood to the
mitochondria within
muscle cells.
May also have an 02 storage function in
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56. C02 Transport
C02 transported in the blood:
HC03- (70%).
Dissolved C02 (10%).
Carbaminohemoglobin (20%).
H20 + C02 ca H2C03
High PC0 2
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57. Chloride Shift at Systemic
Capillaries
H20 + C02 H2C03 H+ + HC03-
At the tissues, C02 diffuses into the RBC; shifts
the reaction to the right.
Increased [HC03-] produced in RBC:
HC03- diffuses into the blood.
RBC becomes more +.
Cl- attracted in (Cl- shift).
H+ released buffered by combining with
deoxyhemoglobin.
HbC02 formed.
Unloading of 02.
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59. At Pulmonary Capillaries
H20 + C02 H2C03 H+ + HC03-
At the alveoli, C02 diffuses into the alveoli;
reaction shifts to the left.
Decreased [HC03-] in RBC, HC03- diffuses into
the RBC.
RBC becomes more -.
Cl- diffuses out (reverse Cl- shift).
Deoxyhemoglobin converted to
oxyhemoglobin.
Has weak affinity for H+.
Gives off HbC02.
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61. Respiratory Acid-Base Balance
Ventilation normally adjusted to
keep pace with metabolic rate.
H2CO3 produced converted to CO2,
and excreted by the lungs.
H20 + C02 H2C03 H+ + HC03-
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62. Respiratory Acidosis
Hypoventilation.
Accumulation of CO2 in the tissues.
Pc02 increases.
pH decreases.
Plasma HCO3 increases.
-
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65. Ventilation During Exercise
During exercise, breathing
becomes deeper and more
rapid.
Produce > total minute volume.
Neurogenic mechanism: Insert fig. 16.41
Sensory nerve activity from
exercising muscles
stimulates the respiratory
muscles.
Cerebral cortex input may
stimulate brain stem
centers.
Humoral mechanism:
PC0 and pH may be different
2
at chemoreceptors.
Cyclic variations in the
values that cannot be
detected by blood samples.
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66. Lactate Threshold and
Endurance Training
Maximum rate of oxygen consumption that
can be obtained before blood lactic acid
levels rise as a result of anaerobic
respiration.
50-70% maximum 02 uptake has been reached.
Endurance trained athletes have higher
lactate threshold, because of higher cardiac
output.
Have higher rate of oxygen delivery to muscles.
Have increased content of mitochondria in skeletal
muscles.
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67. Acclimatization to High Altitude
Adjustments in respiratory function when
moving to an area with higher altitude:
Changes in ventilation:
Hypoxic ventilatory response produces
hyperventilation.
Increases total minute volume.
Increased tidal volume.
Affinity of hemoglobin for 02:
Action of 2,3-DPG decreases affinity of
hemoglobin for 02.
Increased hemoglobin production:
Kidneys secrete erythropoietin.
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