Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
11.18.08(b): Respiratory Control, Ventilation, and Regulation of PaCO2Open.Michigan
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Surfactant & compliance, LAW OF LAPLACE, Work of Breathing (the guyton and ha...Maryam Fida
It is a lipoprotein mixture present in thin layer of fluid lining the alveoli at the air fluid interface.
COMPOSITION
It is composed of
Apoprotein
Calcium ions
Phospholipids i.e. dipalmitoyl lecithin
Surfactant is secreted by
1. Mainly type II alveolar cells in the lungs.
2. Clara cells, which are situated in the bronchioles.
It lowers the surface tension of fluid lining the alveoli.
Surface tension is inversely proportional to surfactant concentration.
During inspiration surfactant molecules move apart as lungs are expanded and during expiration surfactant molecules become concentrated as lungs shorten.
When there is no surfactant, Surface Tension is 50 dynes/cm. when surfactant is present it is 5-30 dynes/cm depending upon the concentration
Prevents collapse of lungs
Stabilize size of alveoli
Surfactant helps to keep lungs expanded. If there is deficiency of surfactant then the pressure of -20 to -30 mm of Hg will be required to keep the lungs expanded
Surfactant also helps to keep the alveoli dry and prevent development of pulmonary edema.
Surfactant is also helpful in lung expansion at birth. If there is deficiency then there is Respiratory Distress Syndrome.
LAW OF LAPLACE:
pressure required to keep a hollow viscous distended = 2 T/R
Where T is tension and R is radius.
During expiration, size of alveoli decreases so R is decreased and if T does not decrease, much higher pressure will be required to keep the alveoli distended.
When adequate amount of surfactant is there T also decreases so increased pressure is not required. This prevents the collapse of lungs and also stabilizes the equal size of alveoli
Definition:
“Compliance is the measure of expansibility or distensibility of the lungs. It indicates with how much ease lungs can be expanded”.
Work of Breathing
In certain diseases there is increased work of breathing and depending upon the nature of breath there will be specific increase in work of breathing.
In asthma there is increase in work of breathing to overcome airway resistance
In restrictive lung diseases there is increase work of breathing in both tissue resistance and elastic recoil.
Slideshow is from the University of Michigan Medical
School's M1 Embryology sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Embryology
01.07.09(b): Introduction to Radiation Oncology, ClinicalOpen.Michigan
Slideshow is from the University of Michigan Medical
School's M2 Hematology / Oncology sequence
View additional course materials on Open.Michigan: openmi.ch/med-M2Hematology
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Outline the various factors affecting airway resistance and correlate it to changes in pulmonary ventilation.
Describe the metabolism of surfactant, discuss its significance and relate its deficiency to clinical conditions.
Define compliance of the lung and chest wall, illustrate and discuss the compliance curve and describe the effect of surfactant on it.
Discuss work of breathing and relate it to clinical conditions.
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
This is a lecture by Jim Holliman, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC- Alterations in Body Temperature: The Adult Patient with a Fever- Reside...Open.Michigan
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC- Rapid Sequence Intubation & Emergency Airway Support in the Pediatric E...Open.Michigan
This is a lecture by Michele Nypaver, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC- Disorders of the Pleura, Mediastinum, and Chest Wall- Resident TrainingOpen.Michigan
This is a lecture by Andrew Barnosky, DO from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC- Dental Emergencies and Common Dental Blocks- Resident TrainingOpen.Michigan
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC- Arthritis and Arthrocentesis- Resident TrainingOpen.Michigan
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC- Bursitis, Tendonitis, Fibromyalgia, and RSD- Resident TrainingOpen.Michigan
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC- Right Upper Quadrant Ultrasound- Resident TrainingOpen.Michigan
This is a lecture by Jeff Holmes from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
This is a lecture by Joe Lex, MD from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC: Nursing Process and Linkage between Theory and PracticeOpen.Michigan
This is a lecture by Jeremy Lapham from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
2014 gemc-nursing-lapham-general survey and patient care managementOpen.Michigan
This is a lecture by Dr. Jeremy Lapham from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
This is a lecture by Dr. Jessica Holly from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
GEMC: The Role of Radiography in the Initial Evaluation of C-Spine TraumaOpen.Michigan
This is a lecture by Dr. Stephen Hartsell from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
This is a lecture by Dr. Jim Holliman from the Ghana Emergency Medicine Collaborative. To download the editable version (in PPT), to access additional learning modules, or to learn more about the project, see http://openmi.ch/em-gemc. Unless otherwise noted, this material is made available under the terms of the Creative Commons Attribution Share Alike-3.0 License: http://creativecommons.org/licenses/by-sa/3.0/.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
Safalta Digital marketing institute in Noida, provide complete applications that encompass a huge range of virtual advertising and marketing additives, which includes search engine optimization, virtual communication advertising, pay-per-click on marketing, content material advertising, internet analytics, and greater. These university courses are designed for students who possess a comprehensive understanding of virtual marketing strategies and attributes.Safalta Digital Marketing Institute in Noida is a first choice for young individuals or students who are looking to start their careers in the field of digital advertising. The institute gives specialized courses designed and certification.
for beginners, providing thorough training in areas such as SEO, digital communication marketing, and PPC training in Noida. After finishing the program, students receive the certifications recognised by top different universitie, setting a strong foundation for a successful career in digital marketing.
Normal Labour/ Stages of Labour/ Mechanism of LabourWasim Ak
Normal labor is also termed spontaneous labor, defined as the natural physiological process through which the fetus, placenta, and membranes are expelled from the uterus through the birth canal at term (37 to 42 weeks
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
1. Author(s): Louis D’Alecy, 2009
License: Unless otherwise noted, this material is made available under the terms of the
Creative Commons Attribution–Non-commercial–Share Alike 3.0 License:
http://creativecommons.org/licenses/by-nc-sa/3.0/
We have reviewed this material in accordance with U.S. Copyright Law and have tried to maximize your ability to use,
share, and adapt it. The citation key on the following slide provides information about how you may share and adapt this
material.
Copyright holders of content included in this material should contact open.michigan@umich.edu with any questions,
corrections, or clarification regarding the use of content.
For more information about how to cite these materials visit http://open.umich.edu/education/about/terms-of-use.
Any medical information in this material is intended to inform and educate and is not a tool for self-diagnosis or a
replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional. Please speak to your
physician if you have questions about your medical condition.
Viewer discretion is advised: Some medical content is graphic and may not be suitable for all viewers.
2. Citation Key
for more information see: http://open.umich.edu/wiki/CitationPolicy
Use + Share + Adapt
{ Content the copyright holder, author, or law permits you to use, share and adapt. }
Public Domain – Government: Works that are produced by the U.S. Government. (USC 17 § 105)
Public Domain – Expired: Works that are no longer protected due to an expired copyright term.
Public Domain – Self Dedicated: Works that a copyright holder has dedicated to the public domain.
Creative Commons – Zero Waiver
Creative Commons – Attribution License
Creative Commons – Attribution Share Alike License
Creative Commons – Attribution Noncommercial License
Creative Commons – Attribution Noncommercial Share Alike License
GNU – Free Documentation License
Make Your Own Assessment
{ Content Open.Michigan believes can be used, shared, and adapted because it is ineligible for copyright. }
Public Domain – Ineligible: Works that are ineligible for copyright protection in the U.S. (USC 17 § 102(b)) *laws in
your jurisdiction may differ
{ Content Open.Michigan has used under a Fair Use determination. }
Fair Use: Use of works that is determined to be Fair consistent with the U.S. Copyright Act. (USC 17 § 107) *laws in
your jurisdiction may differ
Our determination DOES NOT mean that all uses of this 3rd-party content are Fair Uses and we DO NOT guarantee
that your use of the content is Fair.
To use this content you should do your own independent analysis to determine whether or not your use will be Fair.
3. Respiratory Mechanics II
M1 – Cardiovascular/Respiratory
Sequence
Louis D’Alecy, Ph.D.
Fall 2008 3
5. Tidal Volume (TV)
-- air volume entering or leaving
the respiratory system
in a single breath.
It adds to, and mixes with,
alveolar gases.
Contrast with :
Minute ventilation that is total
Ventilation per minute = TV X Rate
5
6. Tidal Volume & Intraplural (Pip)
Inspiration Expiration
Air Air
Entering Leaving
Lung Lung
Pip is -5 -7 -5 6
Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.
7. Mechanics of Breathing Tidal Volume
Figure shows
Spirometer opposite direction,
“down”,
but volume is same
Esophagus balloon
Flow meter
Calculated PA
7
Source Undetermined
8. Trans-pulmonary
or alveolar-distending
pressure .
= PA - Pip
-“across” lung wall
- Pip always negative
- not symmetrical
- max @ end of Insp. 8
Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.
9. Transpulmonary Pressure by
“pumping” into isolated lung (positive)
Hysteresis Isolated Lung
Compliance =
(slope)
V
P
“ease of
stretching” or
“inverse of
elasticity”
9
Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.
10. Transpulmonary Pressure by “sucking”
on outside of isolated lung (negative)
Hysteresis = difference on inflation and deflation
deflation
inflation
-Surfactant
-Recruiting alveoli Source Undetermined
Same with positive or negative pressure. 10
11. Decreased
Compliance
Fibrosis or
stiffer lung
needs more pressure
to get same volume.
11
Source Undetermined
12. Abnormal Compliance
V
P
Emphysema
Greater
volume change
with
smaller Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.
pressure change
12
13. Static P / V Excised Isolated Lung
Air filled harder to inflate than saline filled BUT…
No air = no
surface tension.
Thus
most inflation
pressure is to
overcome
surface tension.
13
Source Undetermined
15. Infant Respiratory Distress Syndrome
• No functional pulmonary surfactant
• Great difficulty inflating lungs
• If inflated for them -- tend to collapse
• Very low compliance (very stiff)
• Strenuous effort needed to breathe
• Die from complete exhaustion
15
16. Work of breathing
Work ~ Pressure change X Volume change
Elastic work overcomes:
recoil of chest wall
recoil of lung parenchyma
surface tension of alveoli
Resistive Work overcomes:
Tissue resistance
Airway resistance
16
17. Airway Resistance
The major determinant of airway resistance is the
radius (r) of the airway, just as in blood vessels.
The walls of the airways are subjected to the same
changes in transmural pressures as alveolar walls.
During inspiration as the intrapleural pressure
decreases (becomes more negative), the transmural
pressure across the airway walls will increase and the
radius of the airway will increase resulting in a
decrease in airway resistance
during inspiration. 17
18. During inspiration
lung volume increases and
airway resistance decreases.
Airway -lateral traction
Resistance
-transpulmonary P or
alveolar distending P
Rest
forced P
r
expiration inspiration ip
Airway r increases
-resistance decreases
Pip
Airway r decreases
- resistance increases
Lung Volume 18
Source Undetermined
19. Measurement of Lung Volumes by
Spirometer
Source Undetermined
Please see: http://www.cvrti.utah.edu/
~macleod/bioen/be6000/labnotes/resp/
figures/spirometer.jpg
Measurement of lung volumes and capacities
and their relationships under different conditions is used
clinically to distinguish obstructive and restrictive disease. 19
20. All Volumes & Capacities
IC VC TLC
Volume
Volume
FRC
Volume
Volume
Source Undetermined
The sum of four volumes determine
the total lung capacity (TLC).
20
21. IC
Volume VC TLC
Volume
FRC
Volume
Volume
Source Undetermined
Each “capacity” is the sum of two or more volumes.
FRC is rest position and made of ERV + RV.
21
VC is maximum tidal volume.
24. FRC & RV
Neither functional residual capacity (FRC)
nor residual volume (RV) can be measured with
simple spirometer.
THREE CLINICAL OPTIONS
1) Gas (helium) dilution******* ( poor solubility )
( no metabolism )
( no diffusion )
2) Nitrogen-Washout Technique
3)Body plethysmography
24
25. Measurement of Functional Residual Capacity
= FRC
Source Undetermined
Before Equilibration After Equilibration
“Dilution”
Amount of He “Before” = Amount of He “After”
25
Solve for V2.
27. Standing increase FRC by increasing ERV
3.5
FRC 3.0
liters
2.5
Standing
2.0
1.5
Source Undetermined
Body position 27
28. FRC Standing is Larger Than FRC Supine
28
Source Undetermined
29. FRC Standing & Supine
When standing the abdominal contents
pull down on diaphragm increasing FRC
so chest has more air in it at rest (FRC).
When supine abdominal contents push
diaphragm up into chest reducing FRC
so chest has less air in it at rest (FRC).
29
31. Airway Resistance 1 (Normal)
Forced expired volume in 1 sec (FEV1) as a
faction of Forced Vital Capacity (FVC)
3.6
=
FEV1
4.5 = 80%
FVC
Fig 2-21 0.7 s
Forced
Expiratory
31
Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed. Flow 25-75%
32. Airway Resistance 2 (Obstruction)
More resistance so less and slower flow
x
3.0
x
FEV1 = 50%
FVC
x
2.7 s
Forced
Expiratory
Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed. Flow 25-75%
32