respiratory physiology all and complete
DESCRIPTION
Hawler Medical University, College of Medicine - Medical Physiology - Respiratory System Physiology - Full Lecture in pptTRANSCRIPT
![Page 1: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/1.jpg)
Respiratory Physiology
Dr Sherwan R Shal2006-2007
1
![Page 2: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/2.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Respiration
Ventilation: Action of breathing with muscles and
lungs.
Gas exchange: Between air and capillaries in the lungs.Between systemic capillaries and tissues
of the body.
02 utilization:Cellular respiration in mitochondria.
2
![Page 3: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/3.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Ventilation
Mechanical process that moves air in and out of the lungs.
Diffusion of…O2: air to blood.
C02: blood to air.
Rapid:large surface area small diffusion distance.
Insert 16.1
3
![Page 4: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/4.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Respiratory structures
4
![Page 5: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/5.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Conducting Zone
Conducting zone:All the structures air passes through before reaching the respiratory zone.
Mouth,nose, pharynx, trachea, glottis, larynx, bronchi.
Insert fig. 16.5
5
![Page 6: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/6.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Conducting Zone
Conducting zone
Warms and humidifies until inspired air becomes:
37 degreesSaturated with water vapor
Filters and cleans:Mucus secreted to trap particles Mucus/particles moved by cilia to be expectorated.
6
![Page 7: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/7.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Respiratory Zone
Respiratory zone
Region of gas exchange between air and blood.
- bronchioles- alveoli
7
![Page 8: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/8.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Respiratory Zone
8
![Page 9: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/9.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Respiratory ZoneAlveoliAir sacsHoneycomb-like clusters~ 300 million.Large surface area (60–80 m2).Each alveolus: only 1 thin cell layer.Total air barrier is 2 cells across (2 m)
(alveolar cell and capillary endothelial cell).
9
![Page 10: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/10.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Respiratory Zone
Alveolar cells:
Alveolar type I: structural cells.
Alveolar type II: secrete surfactant.
10
![Page 11: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/11.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Mechanics of breathing
11
![Page 12: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/12.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Thoracic Cavity
Diaphragm:Sheets of striated muscle divides anterior
body cavity into 2 parts.
Above diaphragm: thoracic cavity:Contains heart, large blood vessels, trachea,
esophagus, thymus, and lungs.
Below diaphragm: abdominopelvic cavity:Contains liver, pancreas, GI tract, spleen, and
genitourinary tract.
12
![Page 13: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/13.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Mechanics of breathing
Gas: the more volume, the less pressure (Boyle’s law).
Inspiration: lung volume increase -> decrease in intrapulmonary pressure, to just
below atmospheric pressure -> air goes in!
Expiration: viceversa
13
![Page 14: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/14.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Mechanics of breathing
Intrapleural space:“Space” between visceral and parietal
pleurae. Visceral and parietal pleurae (membranes)
are flush against each other.Lungs normally remain in contact with the
chest walls. Lungs expand and contract along with the
thoracic cavity.
14
![Page 15: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/15.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Pleura
15
![Page 16: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/16.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Mechanics of breathing
Compliance: lungs can stretch when under tension.
Elasticity: they recoil (to original shape).- elastin
16
![Page 17: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/17.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Inspiration
Inspiration
Diaphragm contracts -> increased thoracic volume vertically.
Intercostals contract, expanding rib cage -> increased thoracic volume laterally.
Active
More volume -> lowered pressure -> air in.Negative pressure breathing.
17
![Page 18: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/18.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Expiration
Expiration
Due to recoil of elastic lungs.Passive.
Less volume -> pressure within alveoli is just above atmospheric pressure -> air leaves lungs.
Note: Residual volume of air is always left behind, so alveoli do not collapse.
18
![Page 19: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/19.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Mechanics of breathing
Quiet breath: +/- 3 mmHg intrapulmonary pressure.
Forced breath:Extra muscles, including abs+/- 20-30 mm Hg intrapulmonary
pressure
19
![Page 20: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/20.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Problems
Pneumothorax: a hole in chest can cause one lung to collapse.
20
![Page 21: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/21.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Surface tension
21
![Page 22: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/22.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Surface Tension
Very thin film of fluid in alveoli.Absorb: Na+ active transport. Secrete: Cl- active transport.
22
![Page 23: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/23.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Surface Tension
Surface tension:H20 molecules at the surface are attracted
to other H20 molecules rather than to air.
Surface tension-> hard to expand the alveoli.Small alveoli, more resistance to expansion.
23
![Page 24: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/24.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Surface tension
Surfactantproduced by alveolar type II cells.Interspersed among water molecules.Lowers surface tension.
RDS, respiratory distress syndrome, in preemies.
First breath: big effort to inflate lungs!
24
![Page 25: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/25.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Surface tension
Insert fig. 16.12
25
![Page 26: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/26.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Measuring pulmonary function
26
![Page 27: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/27.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Pulmonary Function
Spirometry:Breathe into a closed system, with
air, water, moveable bell
Insert fig. 16.16
27
![Page 28: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/28.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Lung volumes
Tidal volume (TV): in/out with quiet breath (500 ml)
Total minute volume: tidal x breaths/min6 L/minExercise: even 200 L/min!
Anatomical dead space:Conducting zoneDilutes tidal volume, by a constant amount.Deeper breaths -> more fresh air to alveoli.
28
![Page 29: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/29.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Lung volumes
Inspiratory reserve volume (IRV): extra (beyond TV) in with forced inspiration.
Expiratory reserve volume (ERV): extra (beyond TV) out with forced expiration.
Residual volume: always left in lungs, even with forced expiration.Not measured with spirometer
29
![Page 30: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/30.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Lung capacities
Vital capacity (VC): the most you can actually ever expire, with forced inspiration and expiration.VC= IRV + TV + ERV
Total lung capacity: VC plus residual volume
30
![Page 31: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/31.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Pulmonary disorders
31
![Page 32: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/32.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Pulmonary disorders Stop
Restrictive disorder:Vital capacity is reduced. Less air in lungs.
Obstructive disorder:Rate of expiration is reduced.Lungs are “fine,” but bronchi are obstructed.
32
![Page 33: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/33.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Disorders
Restrictive disorder:Black lung from coal mines.Pulmonary fibrosis: too much connective tissue.
33
![Page 34: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/34.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Pulmonary Disorders
COPD (chronic obstructive pulmonary disease):AsthmaEmphysemaChronic bronchitis
34
![Page 35: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/35.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Disorders
Obstructive disorder:
FEV = forced expiratory volume.
FEV1 = % of vital capacity expired in 1st second.
Disorder if FEV1 is < 80%
Note: same total amount expired.
Insert fig. 16.17
35
![Page 36: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/36.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Disorders
Asthma:Obstructive Inflammation, mucus secretion, bronchial
constriction.Provoked by: allergic, exercise, cold and dry
airAnti-inflammatories, including inhaled
epenephrine (specific for non-heart adrenergic receptors), anti-leukotrienes, anti-histamines.
36
![Page 37: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/37.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Disorders
Emphysema:Alveolar tissue is destroyed.Chronic progressive condition
Cigarette smoking stimulates macrophages and WBC to secrete enzymes which digest proteins.
Or: genetic inability to stop trypsin (which digests proteins).
37
![Page 38: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/38.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
38
![Page 39: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/39.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
Barometers use mercury (Hg) as convenience to measure total atmospheric pressure.
Sea level: 760 mm Hg (torr)
39
![Page 40: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/40.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
Total pressure of a gas mixture is = to the sum of the independent, partial pressures of each gas (Dalton’s Law).
In sea level atmosphere:PATM = 760 mm Hg = PN2 + P02 + PC02 +
PH20
40
![Page 41: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/41.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
Partial pressures: % of that gas x total pressure.
In atmosphere:
02 is 21%, so (.21 x 760) = 159 mm Hg = P02
Note: atmospheric P02 decreases on a mountain, increases as one dives into the ocean.
41
![Page 42: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/42.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
But inside you, the air is saturated with water vapor.PH20 = 47 mm Hg at 37 degrees
So, inside you, there is less P02:P02 = 105 mm Hg in alveoli.
In constrast, alveolar air is enriched in CO2, as compared to inspired air.
PCO2 = 40 mm Hg in alveoli.
42
![Page 43: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/43.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
Insert fig. 16.20
43
![Page 44: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/44.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
Gas and fluid in contact:[Gas] dissolved in a fluid depends directly on its
partial pressure in the gas mixture.With a set solubility, non changing temp.(Henry’s law)
So…
P02 in alveolar air ~ = P02 in blood.
44
![Page 45: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/45.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
O2 electrodes can measure dissolved O2 in a fluid. (also CO2 electrodes.)
Good index of lung function.
Arterial P02 is only slightly below alveolar P02
Arterial P02 = 100 mm Hg Alveolar P02 = 105 mm Hg
P02 level in the systemic veins is about 40 mm Hg.45
![Page 46: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/46.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
46
![Page 47: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/47.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood gases
Most O2 is in hemoglobin
.3 ml dissolved in plasma + 19.7 ml in hemoglobin 20 ml O2 in 100 mls blood!
But: O2 in hemoglobin-> dissolved -> tissues.
Breathing pure O2 increases only the dissolved portion.
- insignificant effect on total O2
- increased O2 delivery to tissues47
![Page 48: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/48.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Pulmonary Circulation
L ventricle pumps to entire body, R ventricle only to lungs.
Both ventricles pump 5.5 L/min!
Pulmonary circulation: various adaptations.
as a mellow river, doesn’t spill over the bankslow pressure, low resistance.prevents pulmonary edema.pulmonary arteries dilate if P02 is low (opposite of
systemic) 48
![Page 49: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/49.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Neural control
49
![Page 50: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/50.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Neural control
Respiratory centers
In hindbrain
- medulla oblongata
- pons
automatic breathing
Insert fig. 16.25
50
![Page 51: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/51.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Neural control
I neurons = inspiration E neurons = expiration
I neurons -> spinal motor neurons -> respiratory muscles.
E neurons inhibit I neurons.
51
![Page 52: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/52.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Neural control
Also: voluntary breathing controlled by
cerebral cortex.
52
![Page 53: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/53.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Neural control
Ondine’s curse: only voluntary breathing.
Ondine: “water nymph, punished by gods, must stay awake in order to breath.”
Or: she so cursed her philandering husband, after she gave up immortality to join him, and he promised to love her with every waking breath…
http://www.silentpartners.org/sleep/sinfo/miscl/ondine.htm
Gene mutation in fetus:http://news.bbc.co.uk/1/hi/health/2996791.stm
Description:http://www.medterms.com/script/main/art.asp?articlekey=9634
53
![Page 54: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/54.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Chemoreceptors
Oxygen: large “reservoir” attached to hemoglobin.
So chemoreceptors are more sensitive to changes in PC02
(as sensed through changes in
pH).
Ventilation is adjusted to maintain arterial PC02 of 40 mm Hg.
Chemoreceptors are located throughout the body (in brain and arteries).
54
![Page 55: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/55.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
chemoreceptors
55
![Page 56: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/56.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
56
![Page 57: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/57.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Each hemoglobin has 4 polypeptide chains (2 alpha, 2 beta) and 4 hemes (colored pigments).
In the center of each heme group is 1 atom of iron that can combine with 1 molecule 02.
(so there are four 02 molecules per hemoglobin molecule.)
280 million hemoglobin molecules per RBC!57
![Page 58: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/58.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
58
![Page 59: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/59.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Oxyhemoglobin:Ferrous iron (Fe2+) plus 02.
Deoxyhemoglobin:Still ferrous iron (reduced).No 02.
59
![Page 60: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/60.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Carboxyhemoglobin:carbon monoxide (CO) binds to heme
instead of 02
- smokers
60
![Page 61: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/61.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Can tell % of types of hemoglobin by color!
61
![Page 62: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/62.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Loading:Load 02 into the RBC.
Deoxyhemoglobin plus 02 -> Oxyhemoglobin.
Unloading:Unload 02 into the tissues.
Oxyhemoglobin -> deoxyhemoglobin plus 02.
62
![Page 63: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/63.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Loading/unloading depends on:- P02
- Affinity between hemoglobin and 02
- pH- temperature
63
![Page 64: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/64.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Dissociation curve: % oxyhemoglobin saturation at different values of P02.
Describes effect of P02 on loading/unloading.SigmoidalAt low P02 small changes produce large
differences in % saturation and unloading. Exercise: P02 drops, much more unloading from veins.
At high P02 slow to change.
64
![Page 65: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/65.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Oxyhemoglobin Dissociation Curve
Insert fig.16.34
65
![Page 66: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/66.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
66
![Page 67: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/67.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Affinity between hemoglobin and 02:
- pH falls -> less affinity -> more unloading (and viceversa if pH increases)
- temp rises -> less affinity -> more unloadingexercise, fever
67
![Page 68: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/68.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Arteries: 97% saturated (i.e. oxyhemoglobin)Veins: 75% saturated.
Arteries: 20 ml 02 /100 ml blood.Veins: ~ 5 ml less
Only 22% was unloaded!Reservoir of oxygen in case:
- don’t breathe for ~5 min- exercise (can unload up to 80%!)
68
![Page 69: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/69.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Fetal hemoglobin (F):- gamma chains (instead of beta)- more affinity than adult (A) hemoglobin
69
![Page 70: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/70.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Anemias
70
![Page 71: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/71.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hemoglobin
Anemia:[Hemoglobin] below normal.
Polycythemia:[Hemoglobin] above normal.Altitude adjustment.
71
![Page 72: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/72.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Disorders
Sickle-cell anemia:fragile, inflexible RBCinherited change: one base pair in DNA -> one
aa in beta chainshemoglobin Sprotects vs. malaria; african-americans
Thalassemia:defects in hemoglobin
type of anemia
72
![Page 73: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/73.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Disorders
73
![Page 74: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/74.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
RBC
74
![Page 75: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/75.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
RBC
RBCno nucleusno mitochondria
Cannot use the 02 they carry!!!
Respire glucose, anaerobically.
(note: androgens stimulate erythropoiesis)
75
![Page 76: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/76.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Transport of CO2
76
![Page 77: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/77.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
C02 Transport
H20 + C02
carbonic acid
bicarbonate
H2C03 H+ + HC03-
77
![Page 78: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/78.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
C02 transported in the blood:
- most as bicarbonate ion (HC03-)
- dissolved C02
- C02 attached to hemoglobin (Carbaminohemoglobin)
C02 Transport
78
![Page 79: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/79.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
C02 Transport
Carbonic anhydrase in RBC promotes useful changes in blood PC02
H20 + C02 -> H2C03 -> HC03-
high PC02
CA
H20 + C02 <- H2C03 <-
HC03- low PC02
CA
79
![Page 80: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/80.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
C02 Transport
Chloride shift:Chloride ions help maintain electroneutrality.
HC03- from RBC diffuses out into plasma.
RBC becomes more +.Cl- attracted in (Cl- shift).
H+ released buffered by combining with deoxyhemoglobin.
Reverse in pulmonary capillaries80
![Page 81: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/81.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Acid-base balance
81
![Page 82: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/82.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Acid-Base Balance
Ventilation is normally adjusted to keep pace with metabolic rate, so homeostasis of blood pH is maintained.
82
![Page 83: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/83.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Acid-Base Balance
Hyperventilation -> PC02 down -> pH of CSF up -> vasoconstriction -> dizziness.
If hyperventilating, should you breath into paper bag? Yes! It increases PC02!
Metabolic acidosis can trigger hyperventilation.
Diarrhea -> acidosis.Vomit -> alkalosis.
83
![Page 84: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/84.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Adaptations
84
![Page 85: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/85.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Exercise
During exercise, breathing becomes deeper and more rapid.Yet blood gas levels instantly stay about the same. Huh?!
Neurogenic: sensory response from muscles?Humoral: homones? Local differences we can’t sense in a lab?
85
![Page 86: Respiratory Physiology All and Complete](https://reader034.vdocuments.mx/reader034/viewer/2022051820/5528659755034684588b4778/html5/thumbnails/86.jpg)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Adaptations
Frequent exercise, or high altitudes -> series of changes in oxygen consumption, or [hemoglobin], etc.
86