Study sets, textbooks, questions
Upgrade to remove ads
Pathophysiology- pulmonary system
Terms in this set (86)
Movement of air into and out of the lungs
Carried out by pulmonary system
Movement of gases between air spaces in the lungs and the bloodstream
Carried out by pulmonary system
Movement of blood into and out of the capillary beds of the lungs to body organs and tissues
Carried out by cardiovascular system
Space between the lungs, containing the heart, great vessels, esophagus
Warms humidifies air
Oropharynx Connects the upper and lower airways
Ridge where the trachea divides into the right and left bronchi.
Where the right and left bronchi enfer the lungs, along with blood and lymph vessels.
Are hairlike structures.
Goblet and cilia help propel foreign material upward to enable it to be coughed up.
Primary gas exchange units
O2 enters blood and CO2 is removed
Epithelial cells- type 1 and type 2
Type I alveolar cells
Type ll alveolar cells
Prevents lung collapse
Ingest foreign material, and remove it through the lymphatic system
Pulmonary circulation functions
.Facilitates gas exchange.
Delivers nutrients to lung tissues.
Acts as a blood reservoir for the left ventricle.
Serves as a filtering system that removes clots, air, and other debris from the circulation.
Pulmonary circulation has a lower (18 mm Hg) than systemic circulation (90 mm Hg).
Only one third of vessels aře filled with blood a any given time.
PULMONARY AND BRONCHIAL BLOOD SUPPLY
.Gas-exchange airways are served by the pulmonary circulation
Separate division of the circulatory system
Bronchi and other lung structures are served by branch of the systemic circulation Bronchial circulation
High-pressure, low flow
Low-pressure, high flow
High-pressure Bronchial Circulation
Supplies blood to-the frachea, the bronchial tree, bronchioles and outer coats (adventia) of pulmonary arteries and veins
Contains 1-3 % of CO
Lo w-pressure Pulmonary Circulation
Supplies venous blood from all parts of the body to the alveolar capillaries where oxygen is added and carbon dioxide is removed.
Contains 100 % of CO
PULMONARY AND BRONCHIAL CIRCULATION
.Pulmonary artery and accompanying smaller arteries and arterioles have large diameter (where systemic are small)
Gives the pulmonary arterial tree large compliance
Large compliance allows pulmonary arteries to accommodate stroke volume of right ventricle
formed by shared alveolar and capillary walls. Contains the pulmonary capillaries
Gas exchange occurs here
Lymph vessels present in all supportive tissues of the lung
Particulate material entering the alveoli is partly removed by the lymph channels
Plasma protein leaking from lung capillaries is removed from lung tissue
This helps to prevent pulmonary edema
And supports the negative pressure in the lungs to help keep them from collapsing.
Includes the skin , ribs intercostal muscles.
Chest wall Functions:
Protects the lungs from injury; its muscles, in conjunction with the diaphragm, perform the muscular work of breathing
Is contained by the chest wall and encases the lungs.
Adheres firmly to the lungs
Folds over itself, and firmly attaches to the chest wall
Visceral Membrane covering the lungs
Lining the thoracic cavity
Area between the two pleurae: pleural cavity
Fluid lubricates the pleural surfaces, allowing the two layers to slide over each other without separating
Pressure in the pleural space: Negative or subatmospheric (-4 to-10 mm Hg) .
Keeps lungs from collapsing
Normally slight suction=slightly negative Normal pleural pressure at the beginning of inspiration = -5cm/water
This is the amount of suction required to hold lungs open
During normal inspiration, chest cage pulled outward on lungs creating greater negative pressure =-7.5cm/water.
Increase in lung volume of 0.5 Liter
FUNCTIONS OF THE PULMONARY SYSTEM
Ventilate the alveoli.
Diffuse gases into and out of the blood.
Perfuse the lungs, enabling the organs and tissues of the body to receive blood that is rich in oxygen and low in CO2
BPM x TV = Minute volume
Total amount of air moved into and out of respiratory system per minute
Measured on ABG, looking at PaCO2
AV= RR x (TV- dead space)
How much air per minute enters the parts of the respiratory system in which gas exchange takes place
Tidal volume (TV)-
volume of air inspired or expired with each normal breath, -500mL in normal male
Inspiratory reserve volume (IRV)-
extra volume of air that can be inspired over and above the normal tidal volume when the person inspires with full force; 3000mL
Expiratory reserve volume (ERV)
max extra volume of air that can be expired by forceful expiration after the end of a normal tidal expiration; 1100mL
Residual volume (RV)
Residual volume of air remaining in the lungs after the most forceful expiration, 1200mL
Vital Capacity (VC)-
Vital Capacity (VC)- amt of air exchanged from max inspiration fo max expiration
Total Lung Capacity
-total amt of air in the lung after forced inspiration
(C3, C4, C5) innervates diaphragm Receives voluntary and involuntary respiratory messages from CNS
located in the brainstem
Autonomic nervous system controls resp center
Particularly sympathetic and parasympathetic branches control rate and depth of respiration and how big the airway is
Dorsal respiratory group:
Sets the basic automatic rhythm.
Receives impulses from peripheral chemoreceptors in the carotid and aortic bodies:
Detects the Paco2 and the amount of oxygen in the arterial blood.
Ventral respiratory group
Contains inspiratory expiratory neurons. Becomes active when increased ventilatory effort is required.
Pneumotaxic and apneustic centers:
Are located in the pons. Modifiers of the inspiratory depth and rate are established by the medullary centers.
Carbon dioxide and Hydrogen
Increased blood CO2 or Ht stimulate brainstem resp centers to increases respiration to allow to blow off CO2 and decrease blood acidity
Increased Co2 and decreased pH stimulate and carotid bodies (peripheral chemoreceptors) increased firing of aortic
Relay messages to brainstem via CN9 and 10 to increase
Decreased PaO2; carotid and aortic bodies increase signaling to brainstem
Motor cortex send direct innervation to stimulate brainstem Thought that proprioceptive information form contracting skeletal muscles or nerve impulses generated locally for skeleto return to brainstem to stimulate respiratory center
Hering-Breuer inflation reflex
Stretch receptor in bronchiolar and bronchial tree send inhibitory impulses to brain stem that limit excessive inspiration
Is stimulated by hydrogen (H) in the cerebrospinal fluid (pH).
Increases the respiratory depth and rate.
Located in the aorta and carotid bodies.
Is stimulated by hypoxemia (Pao2)
Is responsible for all of the increase in ventilation that occurs in response to arterial hypoxemia.
MUSCLES OF RESPIRATION Inspiration
Downward motion causes negative pressure in chest
This draws in air
External intercostal muscles
Pectoralis major and minor serratus anterior, sternocleidomastoid, scalene muscles, levatores costarum, serratus posterior superior.
Important especially if there is disease
MUSCLES OF RESPIRATION Expiration
Can be voluntary
External and internal intercostal muscles, transversus thoracis, and innermost intercostal muscles, external oblique, internal oblique, and tranversus abdominis
Alveolar surface tension
Surface tension is the attraction of water molecules at air- water interface (raindrop).
Trying to contract In alveoli the water surface is also attempting to contract. .
Results in an attempt to force air out of alveoli and them trying to collapse
Tendency of two molecules to adhere to each other when exposed to air
Detergent like substance secreted by type ll alveolar epithelial cells in lungs
Keeps alveoli open and free of fluid and pathogens (collectins)
Prevents collapse and allows alveoli to expand more easily
the tender wall to return to their resting state after inspiration.
The elastic recoil forces of the lungs and chest wall in opposition and pull on each other, creating the normally negative pressure of the pleural space.
Measures lung and chest wall distensibility Represents relative ease with which these structures can be stretched
Increased work of inspiration
Increased work of expiration
Easy to inflate; has lost some elastic recoil
Gas velocity (Poiseuille's law)
Increases airway resistance
Decreases airway resistance
Work of breathing
Determined by muscular effort
More muscular effort Lung compliance is decreased.
Chest wall compliance is decreased.
Airways are obstructed by bronchospasm or mucous plugs.
Normal 4L/min ventilation and 5L/min of perfusion (4/5=0.8)
Ventilation-perfusion ratio-normal 0.8
Perfusion exceeds venfilation in the bases of the lungs because of grávity
Ventilation exceeds perfusion in the apices of the lungs
Very important in affecting alveolar and therefore arterial levels of oxygen and carbon dioxide
Leads to hypoxemia, increase in CO2
Lowering the V/Q ratio
Low PaO2 and High PaCO2
low ventilation, high perfusign
Decrease numerator and increase denominator .
For example 3/6 0.5 (lower than normal 0.8)
Higher o2 and less CO2
Increasing the V / Q ratio
Higher PaO2 and Lower PaCO2
high ventilation, low perfusion Increase numerator and decrease denominator
For example 5/2 2.5 ( higher than normal 0.8 ) Can be physiologically controlled
PHYSIOLOGICAL CHANGES OF V/Q RATIO
Just by standing up
Perfusion exceeds ventilation in the bases of the lungs because of gravity
Ventilation exceeds perfusion in the apices the lungs
V/q inequality- mismatch
Standard blood gas- from middle of lungs
Well oxygenated blood from top of lungs
More blood than oxygen from bottom of lungs
In cases where the V/Q ratio is low (too little ventilation or too much blood), hypoxic vasoconstriction can occur and causes the blood coming into the area to be directed to other parts of the lung.
Decreasing the perfusion of the hypoxic region will raise the V/Q ratio and bring the arterial blood closer to what expect.
Most important cause of pulmonary artery constriction: Low alveolar partial pressure of oxygen (Pao2)
Acidemia and inflammatory mediators can also cause pulmonary artery constriction.
Low alveolar pao2- pulmonary artery vasoconstriction- main mediator of v/q matching
Body can control both air delivery and blood delivery to lungs
In cases of high V/Q ratio (too much will constrict slightly to to nsrtase increase ventilation, the the resist resistance ance enough and and blood), decrease decrease the bronchi tt amount of ventilation coming into area that is not well perfused (although it won't shut it down entirely).
This limits the amount of alveolar dead space that occurs and minimizes the 'wasted' work.
Delivery of oxygen to the cells of the body and the removal of CO2
Depends on body position and alveolar pressure
Ventilation of the lungs
Diffusion of from the alveoli into the capillary blood
Perfusion of systemic capillaries with oxygenated blood
Diffusion of oxygen from systemic capillaries cells
Diffusion of CO2 occurs in the reverse order.
Effective gas exchange:
Needs approximately even distribution of gas (ventilation) and blood (perfusion) in all portions of the lungs.
Distribution of ventilation and perfusion Gravity and alveolar pressure
Ventilation and perfusion depend on body position.
If a standing individual assumes a supine or side- lying position, the areas of the lungs that are then most dependent become the best ventilated and perfused.
Ventilation of the lungs
Diffusion of oxygen from the alveoli into the capillary blood
Perfusion of systemic capilaries with oxygenated blood .
Diffusion of oxygen from systemic capillaries into cells
Carbon Dioxide removal
.Diffusion of carbon dioxide from the cells into systemic capillaries
Perfusion of the pulmonary capillary bed by venous blood .
Diffusion of carbon dioxide into the alveoli -
Removal of carbon dioxide from the lung by ventilation
PHYSICAL PRINCIPLES OF GAS EXCHANGE
Diffusion in response to concentration gradient
Pressure proportional to concentration
Gas contributes to total pressure in direct proportion to concentration
CO2 20 times as soluble as O2
Diffusion depends on partial pressure of gas
Partial pressure of he gas is driving force of diffusion from high to low
Haldane Effect- amount of O2 in hemaglobin is going to impact what happens with CO2
97 % of oxygen transported from the lungs to the tissues is bound with hemoglobin in red blood cells
3 % is dissolved in plasma
Oxygen binds with heme portion of hemoglobin
Binds in areas of high partial pressure and released areas of low partial pressure
Continues to bind until hemoglobin binding sites are saturated
Diffusion across alveolocapillary membrane diffusion
Ideal medium for oxygen
Large total surface area
Very thin .Partial pressure of oxygen molecules (Po2) is much greater in alveolar gas than it is in capillary blood:
Promotes rapid diffusion from the alveolus into the capillary
Determinants of arterial oxygenation .
Rate of oxygen transport to the tissues in blood
Rate at which oxygen is used by the tissues
TRANSPORT OF OXYGEN TO CELLS
Intracellular partial pressure of oxygen is lower than partial pressure in peripheral capillaries.
Sometimes significant distance between cell and capillary
Intracellular partial pressure of oxygen 5-40mmHg average 23mmHg
Only 1-3 mmHg of oxygen pressure is normally needed for cell usage
Oxyhemoglobin association and dissociation
. Hemoglobin molecules bind with oxygen: Oxyhemoglobin
When hemoglobin saturation and desaturation are plotted on a graph, the result is a distinctive S-shaped curve known as the oxyhemoglobin dissociation curve
Shift to the right depicts the hemoglobin's decreased affinity for oxygen or an increase in the ease with which oxyhemoglobin dissociates and oxygen moves into the cells.
Acidosis (low pH) and hypercapnia and hyperthermia
Shift to the left depicts the hemoglobin's increased affinity for oxygen, which promotes association in the lungs and inhibits dissociation in the tissues.
Alkalosis (high pH) and hypocapnia and hypothermia
: Shift in the oxyhemoglobin dissociation curve caused by changes in CO2 and H+ concentration in the blood
CARBON DIOXIDE TRANSPORT
Amount of carbon dioxide in the blood significant factor in acid-base balance
Retaining too much carbon dioxide will cause an increase in respiratory rate/ventilatory rate.
Carbon dioxide transport in 3 ways
Dissolved in plasma
As CO2 moves into the blood it diffuses into the red blood cells
Carbonic anhydrase combines CO2 and water to form carbonic acid
Carbonic acid dissociates into HCO and Ht 3
H binds to hemoglobin, (buffered), and the HCO3 moves out of the red blood cell into the plasma
60 % venous carbon dioxide is in bicarbonate for 90 % in arterial blood , is in bicarbonate form
Oxygen absorbed from alveoli to blood
Concentration and partial pressure of alveolar oxygen determined by:
Rate of absorption into blood
Rate of entry of new oxygen
Alveolar partial pressure normally 104mmHg
ALVEOLAR CARBON DIOXIDE
Removed from alveoli
Alveolar Partial pressure normally 40mmHg
Partial pressure increases directly in proportion to rate of carbon dioxide excretion
Partial pressure decreases in inverse proportion to alveolar ventilation
AGING AND THE PULMONARY SYSTEM
Loss of elastic recoil
Stiffening of the chest wall
Alterations in gas exchange Increases in flow resistance
Alveoli tend to lose alveoli wall tissue and capillaries
Decrease in Pao2 and diminished ventilatory causing a decrease in exercise tolerance
Decrease in respiratory muscle strength and endurance
too much vitamin D can cause what
What are the phases of the acute inflammatory response?
What are the 2 stages of shock?
what are the most common causes of hyperkalemia?
Recommended textbook explanations
Essential Cell Biology
Bruce Alberts, Dennis Bray, Karen Hopkin
Alton Biggs, Hagins
Biology With Masteringbiology Value Pack (Includes Biology Cd-Rom Investigating Biology Lab Manual)
Jane B. Reece, Lisa A. Urry, Michael L. Cain, Neil A Campbell, Peter V Minorsky, Robert B Jackson, Steven A. Wasserman
Genetic Analysis: An Integrated Approach
John L Bowman, Mark F Sanders
Sets found in the same folder
Pathophysiology Renal & Urologic Systems
Pathophysiology- Fluids &Electrolytes
Pathophysiology Alterations in Renal and Urinary T…
Pathophysiology- CV alterations
Sets with similar terms
Physiology Chapter 16
Chapter 21 Respiration
Pulmonary Structure and Function
Other sets by this creator
Pathophysiology- Neuro patho
Pathophysiology Neuro physiology
Other Quizlet sets
melt hostess test
2015 Honors History Quarter 2 quarterly
Chem Exam 4, ch 33 pt. 2