The document summarizes pulmonary ventilation and lung volumes and capacities. It discusses:
1) The basic functions of the respiratory system including breathing (pulmonary ventilation) which draws gases into and out of the lungs via inhalation and exhalation.
2) The mechanics of breathing including the roles of the diaphragm and intercostal muscles in inspiration and expiration as well as intrapulmonary, intrapleural, and transpulmonary pressures.
3) Lung volumes including tidal volume, inspiratory reserve volume, expiratory reserve volume, residual volume, and total lung capacity.
Regulation of respiration (the guyton and hall physiology)Maryam Fida
Normal respiration is spontaneous and unconscious.
There are 4 groups of neurons on each side in the Pons and medulla oblongata which are involved in regulation of respiration. These include
1. Medullary centers
Dorsal respiratory group of neurons
Ventral respiratory group of neurons
2. Pontine centers
Pneumotaxic centre
Apneustic centre.
It contains “I”neurons which are inspiratory neurons.
It’s located in dorsal portion of medulla oblongata.
It also includes the nucleus of tractus solitarius which is the sensory termination of afferent fibers in 9th ( GLOSSOPHARYNGEAL NERVE) and 10th (VAGUS NERVE) cranial nerves.
They receive impulses from peripheral chemoreceptors, carotid and aortic baroreceptors and also other receptors in the lungs.
In this group inspiratory ramp signals are produced spontaneously.
If we cut the medulla oblongata from other parts of brain and also the afferent nerves which enter the medulla, still inspiratory ramp signals are produced which indicate it’s the inherent property of medulla.
Initially the signal is weak and then it progressively increases and then fades away.
Each ramp signal’s duration is 2 sec and then for 3 seconds there is no ramp signal.
So each cycle lasts for 5 seconds and there are 12 cycles /minute which is the respiratory rate.
Significance of the signal in the form of ramp is that it causes progressive expansion of the lungs. After production, these ramp signals are transmitted to the contra lateral motor neurons supplying the inspiratory muscles.
Rate and duration of inspiratory ramp signals is controlled by impulses from the Pneumotaxic centre and impulses from the lungs via vagi.
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.
Transport of oxygen (the guyton and hall physiology)Maryam Fida
Supply of oxygen to tissues mainly involves two systems i.e. respiratory system and the cardiovascular system.
Supply of oxygen to tissues depends upon
Adequate PO2 in atmospheric air
Adequate pulmonary ventilation
Adequate gaseous exchange in the lungs
Adequate uptake of oxygen by the blood
Adequate blood flow to the tissues
Adequate ability of the tissues to utilize oxygen
Oxygen diffuses from the alveoli into the pulmonary capillary blood because the oxygen partial pressure (Po2) in the alveoli is greater than the Po2 in the pulmonary capillary blood.
In the other tissues of the body, a higher Po2 in the capillary blood than in the tissues causes oxygen to diffuse into the surrounding cells.
The Po2 of the gaseous oxygen in the alveolus averages 104 mm Hg,
whereas the Po2 of the venous blood entering the pulmonary capillary at its arterial end averages only 40 mm Hg
Therefore, the initial pressure difference that causes oxygen to diffuse into the pulmonary capillary is 104 – 40, or 64 mm Hg.
About 98 percent of the blood that enters the left atrium from the lungs has just passed through the alveolar capillaries and has become oxygenated up to a Po2 of about 104 mm Hg.
Another 2 per cent of the blood which supplies mainly the deep tissues of the lungs and is not exposed to lung air. This blood flow is
called “shunt flow,” meaning that blood is shunted past the gas exchange areas
One gram of Hb can bind 1.34 ml of Oxygen
Normal level of Hb is 15 grams/dL
Thus 15 grams of hemoglobin in 100 milliliters of blood can combine with a total of almost exactly 20 milliliters of oxygen if the hemoglobin is 100 per cent saturated
This is usually expressed as 20 volumes per cent
Hemoglobin is a conjugated protein consisting of heme and globin.
The ferrous form can bind oxygen.
Hemoglobin molecule consists of four subunits each consists of one heme and one polypeptide chain
Each subunit can bind one molecule of Oxygen
Oxygenation is a very rapid and reversible process and it can occur in 0.01 seconds
When PO2 is high, oxygen binds with Hb to form Oxyhemoglbin
When PO2 is low oxygen leaves Hb to form Deoxy Hb.
Factors that shift the oxygen hemoglobin dissociation curve
Regulation of respiration (the guyton and hall physiology)Maryam Fida
Normal respiration is spontaneous and unconscious.
There are 4 groups of neurons on each side in the Pons and medulla oblongata which are involved in regulation of respiration. These include
1. Medullary centers
Dorsal respiratory group of neurons
Ventral respiratory group of neurons
2. Pontine centers
Pneumotaxic centre
Apneustic centre.
It contains “I”neurons which are inspiratory neurons.
It’s located in dorsal portion of medulla oblongata.
It also includes the nucleus of tractus solitarius which is the sensory termination of afferent fibers in 9th ( GLOSSOPHARYNGEAL NERVE) and 10th (VAGUS NERVE) cranial nerves.
They receive impulses from peripheral chemoreceptors, carotid and aortic baroreceptors and also other receptors in the lungs.
In this group inspiratory ramp signals are produced spontaneously.
If we cut the medulla oblongata from other parts of brain and also the afferent nerves which enter the medulla, still inspiratory ramp signals are produced which indicate it’s the inherent property of medulla.
Initially the signal is weak and then it progressively increases and then fades away.
Each ramp signal’s duration is 2 sec and then for 3 seconds there is no ramp signal.
So each cycle lasts for 5 seconds and there are 12 cycles /minute which is the respiratory rate.
Significance of the signal in the form of ramp is that it causes progressive expansion of the lungs. After production, these ramp signals are transmitted to the contra lateral motor neurons supplying the inspiratory muscles.
Rate and duration of inspiratory ramp signals is controlled by impulses from the Pneumotaxic centre and impulses from the lungs via vagi.
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.
Transport of oxygen (the guyton and hall physiology)Maryam Fida
Supply of oxygen to tissues mainly involves two systems i.e. respiratory system and the cardiovascular system.
Supply of oxygen to tissues depends upon
Adequate PO2 in atmospheric air
Adequate pulmonary ventilation
Adequate gaseous exchange in the lungs
Adequate uptake of oxygen by the blood
Adequate blood flow to the tissues
Adequate ability of the tissues to utilize oxygen
Oxygen diffuses from the alveoli into the pulmonary capillary blood because the oxygen partial pressure (Po2) in the alveoli is greater than the Po2 in the pulmonary capillary blood.
In the other tissues of the body, a higher Po2 in the capillary blood than in the tissues causes oxygen to diffuse into the surrounding cells.
The Po2 of the gaseous oxygen in the alveolus averages 104 mm Hg,
whereas the Po2 of the venous blood entering the pulmonary capillary at its arterial end averages only 40 mm Hg
Therefore, the initial pressure difference that causes oxygen to diffuse into the pulmonary capillary is 104 – 40, or 64 mm Hg.
About 98 percent of the blood that enters the left atrium from the lungs has just passed through the alveolar capillaries and has become oxygenated up to a Po2 of about 104 mm Hg.
Another 2 per cent of the blood which supplies mainly the deep tissues of the lungs and is not exposed to lung air. This blood flow is
called “shunt flow,” meaning that blood is shunted past the gas exchange areas
One gram of Hb can bind 1.34 ml of Oxygen
Normal level of Hb is 15 grams/dL
Thus 15 grams of hemoglobin in 100 milliliters of blood can combine with a total of almost exactly 20 milliliters of oxygen if the hemoglobin is 100 per cent saturated
This is usually expressed as 20 volumes per cent
Hemoglobin is a conjugated protein consisting of heme and globin.
The ferrous form can bind oxygen.
Hemoglobin molecule consists of four subunits each consists of one heme and one polypeptide chain
Each subunit can bind one molecule of Oxygen
Oxygenation is a very rapid and reversible process and it can occur in 0.01 seconds
When PO2 is high, oxygen binds with Hb to form Oxyhemoglbin
When PO2 is low oxygen leaves Hb to form Deoxy Hb.
Factors that shift the oxygen hemoglobin dissociation curve
Hypoxia :types , causes,and its effects Aqsa Mushtaq
hypoxia :oxygen defecincy at tissue level.in these slides you are going to in touch with its types ,causes effects.share whatever you wanted to say comment us .
these notes are provided by our loving mam MAM SANIA .thanks to teach us mam :)
The apparatus used to measure
Volume of air exchanged during breathing
Respiratory rate
The record is called a spirogram
Upward deflection inhalation
Downward deflection exhalation
One of the academic presentations reflecting the Academic activity at Grande International Hospital, Dhapasi, Kathmandu; an initiative of our HOD of ED, Dr. Ajay Singh Thapa.
Hypoxia :types , causes,and its effects Aqsa Mushtaq
hypoxia :oxygen defecincy at tissue level.in these slides you are going to in touch with its types ,causes effects.share whatever you wanted to say comment us .
these notes are provided by our loving mam MAM SANIA .thanks to teach us mam :)
The apparatus used to measure
Volume of air exchanged during breathing
Respiratory rate
The record is called a spirogram
Upward deflection inhalation
Downward deflection exhalation
One of the academic presentations reflecting the Academic activity at Grande International Hospital, Dhapasi, Kathmandu; an initiative of our HOD of ED, Dr. Ajay Singh Thapa.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
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Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
3. Respiratory system extracts oxygen from the
atmosphere , and the body utilizes the oxygen
and produce CO2 as a result of metabolism.
RESPIRATORY SYSTEM
4. Basic functions of the
respiratory system
1. Breathing (Pulmonary Ventilation) –
movement of air in and out of the lungs
• Inhalation (inspiration) draws gases into
the lungs.
• Exhalation (expiration) forces gases out
of the lungs.
5. Non –pulmonary functions:
2. Gas Conditioning – as gases pass
through the nasal cavity and paranasal
sinuses, inhaled air becomes turbulent. The
gases in the air are
• warmed to body temperature
• humidified
• cleaned of particulate matter
3. Protects respiratory surfaces
4. Site for olfactory sensation
5. Secretes pulmonary alveolar
macrophages
6. Endocrine functions
6. 7. Immune function
8. Vocalization
9. Coughing and sneezing to eliminate
irritants from respiratory tract
10. Production of surfactant
9. Passageway for respiration
Receptors for smell
Filters incoming air to filter larger foreign
material
Moistens and warms incoming air
Resonating chambers for voice
Upper Respiratory Tract Functions
11. Functions:
Larynx: maintains an open airway, routes food
and air appropriately, assists in sound production
Trachea: transports air to and from lungs
Bronchi: branch into lungs
Lungs: transport air to alveoli for gas exchange
Lower Respiratory Tract
12. Mechanics of breathing
Pulmonary ventilation is accomplished
by two processes.
Inspiration is an active process and
refers to inflow of air into the lungs. This
occurs when the intrapulmonary
pressure falls below the atmospheric
pressure.
13. Expiration is a passive process and refers to
outflow of air from the lungs. This occurs
when intrapulmonary pressure exceeds the
atmospheric pressure.
Changes in intrapulmonary pressure which
govern respiratory cycle are related to the
changes in intrapleural pressure.
Changes in intrapleural pressure in turn
depend upon the changes in size of thoracic
cavity.
14. Changes in size of thoracic cavity
depend upon the respiratory muscles
Muscles of normal quiet inspiration are
diaphragm and external intercostal
muscles.
Muscles of forceful inspiration are
sternocledomastoid, scalenes and
parasternals
15. Normal quiet expiration is due to elastic
recoil of lungs
Muscles of forceful expiration are
internal intercostals and abdominal recti
16. movements of inspiration
It is an active process
Normally produced by descent of
diaphragm and contraction of inspiratory
muscles
Therefore diaphragm and external
intercostal muscles contract and cause
increase in vertical, antroposterior and
transverse diameters of thoracic cavity
17.
18. Role of diaphragm
Helps in 70-75% expansion of chest
during normal inspiration
During inspiration , diaphragm contracts
and draw the central tendon part
downwards by 1.5cm in quiet breathing
and 7cm in deep respiration
Cause an increase in vertical diameter
of the thorax
19. Contraction of diaphragm also lifts the
lower ribs causing thoracic expansion
laterally and anteriorly
(the bucket handle and pump handle
movements respectively)
22. Role of external intercostal
muscles
Fibers of external intercostal muscles
are attached to vertebral ends of upper
and lower ribs
Contraction leads to elevation of ribs
causing lateral and antro posterior
enlargement of thoracic cavity
Bucket handle and pump handle
movements.
23. movements of expiration
Passive phenomenon brought about by
elastic recoil of lungs
Decrease in the size of thoracic cavity
by relaxation of diaphragm and external
intercostal muscles
24. mechanism of forced inspiration
Forceful contraction of
diaphragm…..decent 7-10 cm as
compared to 1-1.5 cm in quiet breathing
Forceful contraction of external
intercostal muscles……..increasing
transverse and AP diameter of thoracic
cavity
25. Contraction of accessory muscles
Sternocledomastoid contracts and lifts
the sternum upwards
Anterior serrati and scaleni muscles
contract and lift ribs upwards
26. mechanism of forced expiration
Contraction of abdominal muscles
causes increase in vertical diameter of
thoracic cavity
Downward pull on the lower ribs by
contraction of internal intercostal
muscles decreases AP and transverse
diameter of thoracic cavity
27.
28.
29. Pressure and volume changes during
respiratory cycle
Relationship between intrapulmonary pressure and
atmospheric pressure determines direction of air
flow
In quiet breathing , at end expiration and at end
inspiration .no air is going in and out of the lungs
as the intrapulmonary pressure and atmospheric
pressures are equal i.e. 0 mmHg
30. Intra ALVEOLAR pressure
(IAP)
During normal quiet
inspiration
IAP decreases to about -1
mmHg which is sufficient to
suck in 500 ml of air into
lungs within 2 sec.
At the end of inspiration IPP
decreases again to 0 mmHg
31.
32. During expiration
IAP swings slightly towards positive
side (+1 mmHg) which forces 500 ml of
air out of lungs in 3 sec
At the end of expiration IPP again
decreases to 0 mmHg
33. Significance
Negative pressure in alveoli during
inspiration causes the air to enter into
alveoli but during expiration IAP
becomes positive so air is expelled out
of the lungs
Helps in exchange of gasses between
air and lungs
35. During normal quiet inspiration
It is negative pressure
At the start of inspiration -5mmHg
which is the minimum amount of pressure to
hold the lungs open at resting level
During inspiration becomes more negative
( -7.5mmHg)
During expiration
All the events are reversed during expiration
36. significance
As it is negative pressure so it prevents
the collapse of lungs after elastic recoil
This also causes dilatation of larger
veins and vena cava. So act as suction
pump to pull venous blood from lower
part of the body to increase venous
return.
37. Transpulmonary pressure / recoil
pressure
It is the difference between alveolar
pressure and pleural pressure.
SIGNIFICANCE
It is the measure of elastic forces of
lungs that tend to collapse the lungs at
each instant of respiration
39. Change in lung volume for each unit change in
transpulmonary pressure = stretchiness of lungs
Transpulmonary pressure (TPP) is the
difference in pressure between alveolar
pressure and pleural pressure.
Value of compliance of both lungs in normal
human adult =200ml of air/TPP in cm of H2O
LUNG COMPLIANCE
(Hysteresis)
40. There are 2 different curves
according to different phases
of respiration.
The curves are called :
Inspiratory compliance
curve
Expiratory compliance
curve
COMPLIANCE DIAGRAM
41. Shows the capacity of lungs to “adapt” to
small changes of transpulmonary
pressure.
compliance is seen at low volumes
(because of difficulty with initial lung
inflation) and at high volumes (because of
the limit of chest wall expansion)
The total work of breathing of the cycle is
the area contained in the loop.
42. Two forces try to collapse the
lungs
Elastic forces of lungs
Thin layer of fluid
Two forces prevent collapse of the
lungs
Intra pleural pressure
surfactant
43. Major determinants of
compliance diagram
A.A. Elastic forces of the lung
tissue itself
B. Elastic forces of the fluid
that lines the inside walls of
alveoli and other lung air
passages (surface tension)
44. Elastic forces of the lungs
This is provided by
• Elastin and
• Collagen
interwoven in lung
parenchyma
Deflated lungs: fibers are contracted and in
kinked state
Inflated lungs: these fibers become stretched and
unkinked exerting more elastic forces
45. Elastic forces caused by surface
tension
Is provided by the
substance called
surfactant that is
present inside
walls of alveoli.
46. Experiment:
By adding saline solution there
is no interface between air and
alveolar fluid. (B forces were
removed)
surface tension is not present,
only elastic forces of tissue (A)
Transpleural pressures
required to expand normal lung
= 3x pressure to expand saline
filled lung.
47. Conclusion of this experiment:
Tissue elastic forces (A) =
represent 1/3 of total lung elasticity
Fluid air surface tension elastic
forces in alveoli (B) = 2/3 of total
lung elasticity.
48. Surface tension
water molecules are attracted to one
another.
The force of surface tension acts in the plane
of the air-liquid boundary to shrink or minimize
the liquid-air interface
In lungs = water tends to attract forcing air out
of alveoli to bronchi = alveoli tend to
collapse
50. Forces affecting lung compliance
Deformities of thorax like
Kyphosis
Scoliosis
Fibrosis
Pleural effusion
Paralysis of respiratory muscles
51. Surface agent which tend to decrease
surface tension
Synthesized by type II alveolar cells
Reduces surface tension (prevents
alveolar collapse during
expiration)
Consists of apoproteins +phospholipid
(dipalmitoylphosphatidylcholine) +
calcium ions
surfactant
52. Functions
Decreases surface tension in alveoli
of the lungs
Stabilize the alveoli which have
tendency to deflate
Prevents bacterial invasion
Cleans alveoli surface
53. Plays important role in inflation of lungs
during birth. In fetal life it starts producing
after 3rd
month and completes at 7 months. Till
that time lungs remain collapsed. After birth
inflation of lungs takes place with initiation of
respiration due to CO2 induced activation of
respiratory centers. Although respiratory
movements are attempted again and again by
the new born tend to collapse the lungs.
54. Effects of deficiency of surfactant
Infants: Collapse of the lungs called
Respiratory distress syndrome (RDS) or
hyaline membrane disease
Adults: Collapse of the lungs called
Adult respiratory distress syndrome
(ARDS)
55. Surface active agent in water = reduces
surface tension of water on the alveolar walls
Pure water (surface
pressure)
72
dynes/cm
Normal fluid lining
alveoli without
surfactant (surface
pressure)
50
dynes/cm
Normal fluid lining
alveoli with
surfactant
5-30
dynes/cm
57. Lung Volumes and Capacities
Tidal Volume (VT)
amount of air
entering/leaving
lungs in a single,
“normal” breath
500 ml at rest,
↑ with ↑ activity
IC
FRC
VC
TLC
Lung Capacities
Primary Lung
Volumes
IRV
VT
ERV
RV
Volume(ml)
0
6000
58. Inspiratory Reserve
Volume (IRV)
additional volume of
air that can be
maximally inspired
beyond VT by forced
inspiration
3000 ml. at rest
IC
FRC
VC
TLC
Lung Capacities
Primary Lung
Volumes
IRV
VT
ERV
RV
Volume(ml)
0
6000
59. Expiratory
Reserve Volume
(ERV)
additional volume
of air that can be
maximally expired
beyond VT by
forced expiration
1100 ml. at rest
IC
FRC
VC
TLC
Lung Capacities
Primary Lung
Volumes
IRV
VT
ERV
RV
Volume(ml)
0
6000
60. Residual Volume
(RV)
volume of air still in
lungs following
forced max.
expiration
1200 ml. at rest
IC
FRC
VC
TLC
Lung Capacities
Primary Lung
Volumes
IRV
VT
ERV
RV
Volume(ml)
0
6000
61. Total Lung Capacity
(TLC)
total amount of air
that the lungs can
hold
amt of air in lungs at
the end a maximal
inspiration
VT + IRV + ERV +
RV
5800ml at rest
IC
FRC
VC
TLC
Lung Capacities
Primary Lung
Volumes
IRV
VT
ERV
RV
Volume(ml)
0
6000
62. Vital Capacity (VC)
max. amt. air that
can move out of
lungs after a person
inhales as deeply as
possible
VT + IRV + ERV
4600ml at rest
IC
FRC
VC
TLC
Lung Capacities
Primary Lung
Volumes
IRV
VT
ERV
RV
Volume(ml)
0
6000
63. Inspiratory Capacity
(IC)
max amt. of air that can
be inhaled from a
normal end-expiration
breathe out normally,
then inhale as much as
possible
VT + IRV
3500ml at rest
IC
FRC
VC
TLC
Lung Capacities
Primary Lung
Volumes
IRV
VT
ERV
RV
Volume(ml)
0
6000
64. Functional Residual
Capacity (FRC)
amt of air remaining in
the lungs following a
normal expiration
ERV +RV
2300ml at rest
IC
FRC
VC
TLC
Lung Capacities
Primary Lung
Volumes
IRV
VT
ERV
RV
Volume(ml)
0
6000
65. Forced Expiratory Volume
(FEVt)
Amount of air forcibly
expired in t seconds
FEVt = (Vt/VC) x 100%
Normally…
FEV1 = ~ 80% VC
FEV2 = ~ 94% VC
FEV3 = ~ 97% VC
Index of air flow through
the respiratory air
passages
0 1 2 3
5000
4000
3000
2000
1000
0
Time (sec)Volume(ml)
FEV1 = (5000 ml -1000 ml) / 5000ml
= 4000 ml / 5000 ml
= 80%
66. Restrictive and Obstructive Disorders
Restrictive
disorder:
Vital capacity is
reduced.
FVC is normal.
Obstructive
disorder:
VC is normal.
FEV1 is < 80%.
Insert fig. 16.17
Figure 16.17
67. Air-Flow Disorders
Obstructive disorders
obstruction of the pulmonary air passages
air flow α radius4
slight obstruction will have large ↓ in air flow
bronchiolar secretions, inflammation and edema
(e.g. bronchitis), or bronchiolar constriction (e.g.
asthma)
reduced FEV, normal VC
Restrictive disorders
damage to the lung results in abnormal VC test
e.g. pulmonary fibrosis
reduced VC, normal FEV
68. Ventilation
PULMONARY
VENTILATION
ALVEOLAR
VENTILATION
Cyclic process by which
fresh air enters and leaves
the lungs
Air utilized for gaseous
exchange
Product of TV and RR Product of TV excluding
dead space volume and RR
PV=TV X RR
500ml X 12/min
600ml or 6L/min
AV= (TV-DSV) X RR
(500-150) X 12/min
4.200ml or 4.2 L/min
69. Dead space
Part of respiratory tract where gaseous
exchange doesn’t take place
Types:
Anatomical dead space
Physiological dead space
70. ANATOMICAL DEAD SPACE
Volume of respiratory tract from nose
up to terminal bronchiole
PHYSIOLOGICAL DEAD SPACE
Includes anatomical dead space plus
well perfused but non ventilated alveoli
and well ventilated but non perfused
alveoli
71. NORMAL VALUE OF DEAD
SPACE
Under normal conditions ADS + PDS
So DSV = 150 ml
MEASUREMENT
BY N2 Wash method
74. vocal cords get approximated so air
trapped in
abdominal muscles contract forcefully
so that pressure exceeds 100 mmHg or
more
Epiglottis suddenly gets open, air
under high pressure in lungs exploded
out with the velocity of 70-100 miles
/hour