Respiratory Physiology Lecture 6 Pulmonary circulation and ...
Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between...
-
date post
21-Dec-2015 -
Category
Documents
-
view
215 -
download
0
Transcript of Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between...
![Page 1: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/1.jpg)
Pulmonary Function During Exercise
Chapter 10
![Page 2: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/2.jpg)
The Respiratory System
Provides gas exchange between the environment and the body
Regulates of acid-base balance during exercise
![Page 3: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/3.jpg)
Ventilation
Moving Air
![Page 4: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/4.jpg)
Conducting and Respiratory Zones
Conducting zone Conducts air to
respiratory zone Humidifies, warms,
and filters air Components:
– Trachea– Bronchial tree– Bronchioles
Respiratory zone Exchange of gases
between air and blood Components:
– Respiratory bronchioles
– Alveolar sacs
![Page 5: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/5.jpg)
Pathway of Air to Alveoli
![Page 6: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/6.jpg)
Mechanics of Breathing
Ventilation– Movement of air into and out of the lungs via bulk
flow Inspiration
– Diaphragm pushes downward, lowering intrapulmonary pressure
Expiration– Diaphragm relaxes, raising intrapulmonary pressure
Resistance to airflow – Largely determined by airway diameter
![Page 7: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/7.jpg)
The Mechanics of Inspiration and Expiration
![Page 8: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/8.jpg)
Pulmonary Volumes and Capacities
Measured by spirometry Vital capacity (VC)
– Maximum amount of air that can be expired following a maximum inspiration
Residual volume (RV)– Air remaining in the lungs after a maximum expiration
Total lung capacity (TLC)– Sum of VC and RV
![Page 9: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/9.jpg)
Pulmonary Volumes and Capacities
Inspiratory Reserve volume (IRV)– Maximum amount of air that can be inspired following a
normal inspiration Expiratory reserve volume (ERV)
– Air remaining in the lungs after a normal expiration
![Page 10: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/10.jpg)
A Spirogram Showing Pulmonary Volumes and Capacities
![Page 11: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/11.jpg)
Check measurements to find:
Norms for body sizes Indications of healthy lung function Indications of diseases/conditions that
affect ventilation– Asthma– Emphysema
![Page 12: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/12.jpg)
Pulmonary Ventilation (VE)
The amount of air moved in or out of the lungs per minute– Product of tidal volume (VT)
and breathing frequency (FB)
– (looks similar to Q = SV x HR? )
VE = VT x FB
.
.
.
![Page 13: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/13.jpg)
Respiration
Movement of gasses
![Page 14: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/14.jpg)
Diffusion of Gases
Gases diffuse from high low partial pressure
– From lungs to blood and back to lungs– From blood to tissue and back to blood
![Page 15: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/15.jpg)
Partial Pressure of Gases
Each gas in a mixture exerts a portion of the total pressure of the gas
The partial pressure of oxygen (PO2)
– Air is 20.93% oxygen• Expressed as a fraction: 0.2093
– If total pressure of air = 760 mmHg, then
PO2 = 0.2093 x 760 = 159 mmHg
![Page 16: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/16.jpg)
Partial Pressure and Gas Exchange
![Page 17: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/17.jpg)
O2 Transport in the Blood
O2 is bound to hemoglobin (Hb) for transport in the blood– Oxyhemoglobin: O2 bound to Hb
Carrying capacity – 201 ml O2•L-1 blood in males
• 150 g Hb•L blood-1 x 1.34 mlO2•g Hb-1
– 174 ml O2•L-1 blood in females
• 130 g Hb•L blood-1 x 1.34 mlO2•g Hb-1
![Page 18: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/18.jpg)
Oxyhemoglobin Dissociation Curve
![Page 19: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/19.jpg)
O2-Hb Dissociation Curve: Effect of pH Blood pH declines during heavy
exercise Results in a “rightward” shift of the
curve– Bohr effect
– Favors “offloading” of O2 to the tissues
![Page 20: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/20.jpg)
O2-Hb Dissociation Curve: Effect of pH
20
1816
1412
10 8 6
4 2
Oxy
gen
Con
tent
(ml O
2 / 1
00 m
l blo
od)
Amount of O2
unloaded
![Page 21: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/21.jpg)
O2-Hb Dissociation Curve: Effect of Temperature Increased blood temperature results in
a weaker Hb-O2 bond Rightward shift of curve
– Easier “offloading” of O2 at tissues
![Page 22: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/22.jpg)
O2-Hb Dissociation Curve: Effect of Temperature
Amountoffloaded
Oxy
gen
Con
tent
(ml O
2 / 1
00 m
l blo
od)
![Page 23: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/23.jpg)
O2 Transport in Muscle
Myoglobin (Mb) shuttles O2 from the cell membrane to the mitochondria
Higher affinity for O2 than hemoglobin
– Even at low PO2
– Allows Mb to store O2
![Page 24: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/24.jpg)
Dissociation Curves for Myoglobin and Hemoglobin
![Page 25: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/25.jpg)
Carbon Dioxide Transport
Not identical to oxygen transport
![Page 26: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/26.jpg)
CO2 Transport in Blood
Dissolved in plasma (10%) Bound to Hb (20%) Bicarbonate (70%)
CO2 + H2O H2CO3 H+ + HCO3-
MuscleNormal Metabolism
binds to HbCarbonic Acid
Bicarbonate
![Page 27: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/27.jpg)
CO2 Transport in Blood
Dissolved in plasma (10%) Bound to Hb (20%) Bicarbonate (70%)
CO2 + H2O H2CO3 H+ + HCO3-
Lung Ventilation
O2 replaces on Hb
![Page 28: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/28.jpg)
CO2 Transport in Blood
Dissolved in plasma (10%) Bound to Hb (20%) Bicarbonate (70%)
CO2 + H2O H2CO3 H+ + HCO3-
– Also important for buffering H+
Muscle
Lung
Intense Exercise
Ventilation
![Page 29: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/29.jpg)
Release of CO2 From Blood
![Page 30: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/30.jpg)
Effect of Respiratory Gases on Ventilation
How do these gasses affect breathing?
![Page 31: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/31.jpg)
Control of Ventilation
Respiratory control center in the brainstem– Regulates respiratory rate– Receives neural and humoral input
• Feedback from muscles
• PO2, PCO2, H+, and K+ in blood
• PCO2 and H+ concentration in cerebrospinal fluid
![Page 32: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/32.jpg)
Effect of Arterial PO2 on Ventilation
![Page 33: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/33.jpg)
Effect of Arterial PCO2 on Ventilation
![Page 34: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/34.jpg)
Ventilation and Acid-Base Balance
Blood pH is regulated in part by ventilation
An increase in ventilation causes exhalation of additional CO2
– Reduces blood PCO2
– Lowers H+ concentration
H+ + HCO3- H2CO3 H2O + CO2
Exhalation
![Page 35: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/35.jpg)
Ventilatory Control During Submaximal Exercise
![Page 36: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/36.jpg)
Incremental Exercise
Linear increase in ventilation – Up to ~50-75% VO2max
Exponential increase beyond this point Ventilatory threshold (Tvent)
– Inflection point where VE increases exponentially
.
.
![Page 37: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/37.jpg)
Ventilatory Response to Exercise:Tvent
![Page 38: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/38.jpg)
Is This Trainable?
Does an endurance trained person breathe less?
Does an endurance trained person need less oxygen?
![Page 39: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/39.jpg)
Effect of Training on Ventilation
Ventilation is lower at same work rate following training– May be due to lower blood lactic acid levels– Results in less feedback to stimulate
breathing
– Well trained produce less CO2 – stim. for breathing
![Page 40: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/40.jpg)
Effects of Endurance Training on Ventilation During Exercise
![Page 41: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/41.jpg)
Ventilatory Response to Exercise:Trained vs. Untrained In the trained runner
– Decrease in arterial PO2 near exhaustion• more oxygen extracted
– pH maintained at a higher work rate• less lactic acid produced – “aerobic metab.”
– Tvent occurs at a higher work rate• lower relative intensity
![Page 42: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/42.jpg)
Ventilatory Response to Exercise:Trained vs. Untrained
![Page 43: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/43.jpg)
Do the Lungs Limit Exercise Performance? Sub maximal exercise
– Pulmonary system not seen as a limitation Maximal exercise
– Not thought to be a limitation in healthy individuals at sea level
– May be limiting in elite endurance athletes
![Page 44: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/44.jpg)
Questions?
![Page 45: Pulmonary Function During Exercise Chapter 10. The Respiratory System Provides gas exchange between the environment and the body Regulates of acid-base.](https://reader035.fdocuments.in/reader035/viewer/2022062421/56649d5d5503460f94a3c948/html5/thumbnails/45.jpg)
End