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Physiology Module > Module 7: Respiratory System > Flashcards

Module 7: Respiratory System Flashcards

1
Q

Respiratory System

A

UPPER AIRWAYS - Nose, Sinuses, Larynx

LOWER AIRWAYS - Trachea, Airways, Alveoli

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2
Q

Nose: FUNCTIONS

A

warm (cold dry air damages the respiratory epithelium),
humidify (add water droplets to the air going in,
filter (prevent large particles from going in),
smell (olfactory neurons,only neurons capable for reproduction, are found in upper part of the nose),
defense

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3
Q
  • air filled spaces that lightens the skull
  • composed of frontal sinuses, maxillary sinus, sphenoid sinus, ethmoid sinus
  • Surround nasal passageways
A

Sinuses

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4
Q

Functions of Sinuses

A
  1. Lighten skull

2. Offer resonance to voice (improves the speech)

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5
Q
  • last part of the upper airway
  • voicebox
  • MAJOR STRUCTURES
  • Vocal Cords
  • Epiglottis, Arytenoids
A

Larynx

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6
Q
  • Covers the vocal cords during swallowing

- cover the entrance to the trachea during swallowing

A

Epiglottis, Arytenoids

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7
Q
  • part of the lower airway; airway that leads to the bronchus
  • In the trachea, C-shaped cartilages are found
A

Trachea

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8
Q

Trachea, Bronchi, Bronchioles

A

Trachea&raquo_space; Main Stem Bronchi&raquo_space; Lobar Bronchi&raquo_space; Segmental Bronchi&raquo_space; Terminal bronchioles&raquo_space; Respiratory bronchiole Alveoli

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9
Q

BRONCHI

A

Right vs Left: Right bronchi is wider, shorter and more vertical
Implication: will be common for aspiration on the RIGHT bronchi

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10
Q

BRONCHIOLE

A

Terminal Bronchiole vs Respiratory Bronchiole:

Terminal bronchiole - the distal part of the airway that has no alveoli or alveolar sacs; last part that has no gas exchange

Respiratory Bronchiole is capable of Gas Exchange

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11
Q
  • give rise to bronchopulmonary segment
A

Segmental Bronchi

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12
Q
  • consists of 8-10 per lung

- will have its own blood and nerve supply

A

Bronchopulmonary segments

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13
Q

3 Areas capable of gas exchange

A
  1. Respiratory Bronchioles
  2. Alveolar Ducts
  3. Alveoli
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14
Q
  • (+) presence of Respiratory Epithelium (pseudostratified ciliated columnar epithelium with goblet cells
  • Maintains periciliary fluid so that cilia may function
  • GOBLET CELLS, SUBMUCOSAL GLANDS
  • CLARA CELLS (CLUB CELLS)
A

Trachea, Bronchi, Bronchioles

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15
Q
  • Produces Mucus for lubrication

- Hyperplasia, Hypertrophy seen in chronic smokers

A

GOBLET CELLS, SUBMUCOSAL GLANDS

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16
Q
  • Controversial
  • nonciliated cells found in the respiratory epithelium
  • May play a role in EPITHELIAL REGENERATION after injury
A

CLARA CELLS (CLUB CELLS)

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17
Q
  • moves the dust debris towards the mouth

- has a unidirectional movement

A

Cilia

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18
Q

COUGH REFLEX

A
  1. 2.5 L of air rapidly inspired
  2. Epiglottis closes
  3. Abdominal muscles contract
  4. Epiglottis opens
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19
Q
  • Similar to cough reflex but applied to nasal passageways (upper respiratory passageways)
  • with depression of the uvula to force air to go to the nose
  • removes the irritating factor
A

SNEEZE REFLEX

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20
Q
  • Weighs 1kg
  • 60% lung tissue
  • 40% blood
  • Alveolar Spaces
  • Gas Exchange Area: 70 -80 m2
A

Lungs

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21
Q
  • Responsible for most of lung’s volume

- Divided by lung interstitium (tissue in between alveolar spaces)

A

Alveolar Spaces

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22
Q

Lungs

A

RIGHT LUNG

  • 3 Lobes (Upper, Middle, Lower)
  • Oblique Fissure, Horizontal Fissure

LEFT LUNG

  • 2 Lobes (Upper, Lower)
  • has lingula
  • Oblique Fissure
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23
Q
  • VISCERAL PLEURA - closely attach to the lungs
  • PARIETAL PLEURA - closely attach to the chest wall
  • PLEURAL FLUID
A

Lungs

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24
Q
  • Found in potential space between the two pleura
  • Keeps the 2 pleura together (allows them to slide)
  • Has negative pressure
A

PLEURAL FLUID

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25
- air inside the pleural space that cause the lungs to expand limitedly during inspiration
Pneumothorax
26
- water inside the pleural space
Pleural Effusion
27
- pus collection in the pleural space secondary to infection
Empyema
28
- 5 x 108 alveoli - Made up of 2 Cells in a 1:1 ratio * TYPE I Pneumocytes * TYPE II Pneumocytes
Alveoli
29
- 96-98% of surface area | - For Gas Exchange
TYPE I PNEUMOCYTE
30
- 2-4% of surface area - Small, cuboidal, found at corners of alveoli - May turn into Type I if needed - For surfactant production (Decreases surface tension)
TYPE II PNEUMOCYTE
31
- Force caused by water molecules at the air-liquid interface that tends to minimize surface area
Surface Tension
32
(Surface Tension of the Alveoli) P=2T/r (P=Collapsing Pressure on alveolus, T=Surface Tension, r=radius of alveolus) - Smaller alveoli would likely collapse if not for surfactant
LAPLACE LAW
33
Laplace Law
- Collapsing Pressure is directly proportional to the surface tension - Collapsing Pressure is indirectly proportional to the radius * The higher the surface tension, the higher the collapsing pressure * The smaller the radius, the higher the collapsing pressure
34
- Synthesized by Type II alveolar cells - Made up of DPPC (Dipalmitoylphosphatidylcholine), phosphatidylglycerol, surface apoproteins, calcium ions - reduces surface tension (to 5-30 dynes/ cm) and increases compliance - It also reduces capillary filtration forces (Reduces the possibility of pulmonary edema)
Pulmonary Surfactant
35
Causes of Respiratory Distress of the Newborn (Preterm)
1. Immature surfactant | 2. Smaller Alveoli (which means small radius)
36
- active component of surfactant - act as a detergent which decrease surface tension - also known as Lecithin
Dipalmitoylphosphatidylcholine
37
Which blood vessels are involved in hemoptysis?
Bronchi Blood vessels
38
- Also contributes to alveoli stability - One alveoli exerts traction on surrounding alveoli prevents collapse (alveolar collapse) - has 2 structures that prevents it: Pores of Kohn and Canals of Lambert
Interdependence
39
Connects alveoli to adjacent alveoli
PORES OF KOHN
40
Connects terminal airway to adjacent alveoli
CANALS OF LAMBERT
41
(Lung Interstitium) - Secretes Collagen (limits Lung Distensibility) - Secretes Elastin (contributes to Elastic Recoil of lung)
FIBROBLASTS
42
(Lung Interstitium) - Supports conducting airways
CARTILAGE
43
(Lung Interstitium) - Dilate or constrict airways
SPIRAL SMOOTH MUSCLES
44
(Lung Interstitium) - Secrete dopamine, serotonin
KULCHITSKY CELLS, NEUROENDOCRINE CELLS
45
(Pulmonary Circulation) - very thin and distensible - carries deoxygenated blood
PULMONARY ARTERIES
46
(Pulmonary Circulation) - same as the systemic veins - most oxygenated area; 100% of oxygenated blood
PULMONARY VEINS
47
(Pulmonary Circulation) | DUAL BLOOD SUPPLY OF THE LUNGS
1. PULMONARY CIRCULATION | 2. BRONCHIAL CIRCULATION
48
- role is to pick up oxygen for the nonpulmonary parts of the body - Carries DEOXYGENATED BLOOD to the lungs - “Sheet” of capillaries in the alveoli - Pulmonary Veins returns to L atrium
PULMONARY CIRCULATION
49
- gives up oxygen - Carries OXYGENATED BLOOD to the lungs - 1-2% of cardiac output - 1/3 returns to Right atrium via bronchial veins, 2/3 goes to the Left atrium via pulmonary veins
BRONCHIAL CIRCULATION
50
Pulmonary Circulation: Lymphatic Vessels of the Pulmonary System
- start from the terminal bronchioles - drains into the RIGHT LYMPHATIC DUCT - Removes particulate matter and plasma proteins - Creates negative pressure in the pleural space
51
(Pulmonary Circulation Pressures) RIGHT VENTRICULAR PRESSURE
25/0 mmHg
52
(Pulmonary Circulation Pressures) PULMONARY ARTERY PRESSURE
25/8 mmHg
53
(Pulmonary Circulation Pressures) PULMONARY CAPILLARY PRESSURE
7 mmHg
54
(Pulmonary Circulation Pressures) LEFT ATRIAL AND PULMONARY VEIN PRESSURE
1-5 mmHg
55
- used to estimate Left atrial pressure | - whatever pressure that is in here it's 2-3 mmHg higher that the Left atrial pressure
PULMONARY CAPILLARY WEDGE PRESSURE (PCWP)
56
Clinical Significance of measuring Pulmonary Capillary Wedge Pressure
Enables us to differentiate between diseases like Cardiogenic Pulmonary Edema and Acute Respiratory Distress Syndrome in Adult
57
Cardiogenic Pulmonary Edema vs Acute Respiratory Distress Syndrome in Adult
Cardiogenic Pulmonary Edema >> Increase PCWP due to increase atrial pressure (involves the heart) Acute Respiratory Distress Syndrome in Adult >> Decrease PCWP (involves the lungs)
58
Blood Volume, Blood Flow in the lungs
- Blood Volume of the lungs: 450 mL - Hypoxia in the lungs causes Vasoconstriction - All other organs: hypoxia causes Vasodilation - Blood flow in the lungs is divided into theoretical 3 Zones
59
All arterioles in the body their response to Hypoxia is __
VASODILATION (to provide more oxygen to go to the organ like muscles)
60
Pulmonary arterioles response to Hypoxia is __
VASOCONSTRICTION (to shunt blood among areas for better oxygenation)
61
Lungs are not uniformly oxygenated
Base receive more oxygen or air more on the Apex
62
Lung Zones (Scenarios)
Zone 1 Zone 2 Zone 3
63
- No Blood flow | - local alveolar capillary pressure
Zone 1
64
- Intermittent Blood Flow (Blood flow during systole; No Blood flow during diastole) - local alveolar capillary systolic pressure > alveolar air pressure but less than that during diastole
Zone 2
65
- Continuous Blood Flow | - local alveolar capillary pressure > alveolar air pressure throughout the cycle
Zone 3
66
Lung Zone during Sitting upright
Upper third of the Lungs - Zone 2/3 | Middle and Lower third of the Lungs - Zone 3 exclusive
67
Lung Zone during Exercise
The entire lung is in Zone 3 (Continuous)
68
Lung Zone during Supine Position
The entire lung is in Zone 3 (Continuous)
69
Innervation
LUNGS - Under Autonomic Nervous System (ANS) Control - No pain fibers (Pain fibers are found only in the pleura) MUSCLES OF RESPIRATION Under Somatic Control
70
(ANS Control of the Lungs): SYMPATHETIC
- bronchodilation (Beta 2 >> Relax smooth muscle >> will cause BRONCHODILATION) - Airway relaxation, blood vessel constriction, inhibition of glandular secretion
71
(ANS Control of the Lungs): PARASYMPATHETIC
- Bronchoconstriction (Muscarinic(acetylcholine) >> Bronchial smooth muscle to contract >> BRONCHOCONSTRICTION) - Airway constriction, blood vessel dilation, increased glandular secretion
72
Muscles Involved in Pulmonary Ventilation: INSPIRATION
NORMAL INSPIRATION: Active Process (Diaphragm) FORCED INSPIRATION (happens during exercise): External Intercostals, SCM, Anterior Serrati, Scalene, Alae Nasi, Genioglossus, Arytenoid *Accessory muscle + External intercostal
73
Muscles Involved in Pulmonary Ventilation: EXPIRATION
NORMAL ESPIRATION: Passive Process FORCED EXPIRATION: rectus abdominis, Internal and External Oblique, Transversus Abdominis, Internal Intercostals *Abdominal muscles + Internal Intercostal
74
How do the lungs contract and expand?
Diaphragmatic upward and downward movement >> Chest cavity lengthening and shortening Rib upward and downward rotation >> Increase and decrease thoracic AP diameter
75
Elastic Forces of the Lungs and Thorax
LUNGS - inwardly directed elastic recoil; tendency is to collapse CHEST WALL - outwardly directed elastic recoil; tendency is to expand
76
Elastic Forces of the Lungs and Thorax
Before Inspiration/After Expiration - At Functional Residual Capacity, Recoil forces from lungs and thorax are equal and opposite (pressure in the alveoli is the same the pressure in the air in the atmosphere = no air will go in and out)
77
Pressures in the Pulmonary System: PLEURAL PRESSURE (pressure inside the pleural cavity)
Start of inspiration: -5cm H2O | End of inspiration: -7.5cm H20
78
Pressures in the Pulmonary System: ALVEOLAR PRESSURE
Start of Inspiration: 0cm H20 | End of Inspiration: -1cm H20
79
- (Alveolar Pressure – Pleural Pressure) | - Measure of Recoil Pressure
TRANSPULMONARY PRESSURE
80
- Extent to which lungs will expand for each unit increase in transpulmonary pressure - Normal Value = 200 ml or air/cm of water transpulmonary pressure - Determined by Lung Elasticity
Lung Compliance
81
TOTAL LUNG ELASTICITY
- 1/3 due to Tissue Lung Elasticity | - 2/3 due to Fluid-Air Surface Tension Forces in the Alveoli
82
- Determined by properties of the lung parencyma and interaction between the lungs and chest wall - 4 Basic Lung Volumes
LUNG VOLUMES
83
- Sum of 2 or more lung volumes
LUNG CAPACITIES
84
LUNG VOLUMES
- Inspiratory Reserve Volume (IRV) - Tidal Volume (TV) - Expiratory Reserve Volume (ERV) - Residual Volume (RV)
85
Sum of - Inspiratory Reserve Volume (IRV) - Tidal Volume (TV) - Expiratory Reserve Volume (ERV)
Vital Capacity
86
Sum of - Inspiratory Reserve Volume (IRV) - Tidal Volume (TV)
Inspiratory Capacity
87
Sum of - Expiratory Reserve Volume (ERV) - Residual Volume (RV)
Functional Residua Capacity
88
What’s the difference in Lung Volumes and Capacities between males and females?
Females; 20-25% lower in females
89
- the amount of air that we normally inhale or exhale - 500ml - Normal Quiet Breathing Volume
Tidal Volume
90
- is the volume of air remaining in the lungs after the most forceful expiration - 1200 ml - Left in Lungs after maximal expiration - function: maintain oxygenation of blood in between breaths and breath holding
Residual Volume (RV)
91
- extra volume of air that can be inspired over and above the normal tidal volume when the person inspires with full force - 3000 ml - Above Tidal volume w/max inspiration
Inspiratory Reserve Volume (IRV)
92
- is the maximum extra volume of air that can be expired by forceful expiration after the end of a normal tidal expiration - 1100 ml - Forcefully expired at Tidal volume end
Expiratory Reserve Volume (ERV)
93
- this capacity is the amount of air a person can breathe in, beginning at the normal expiratory level and distending the lungs to the maximum amount - 3500ml - From normal expiratory level up to max voume. lung can be distended - VT+IRV
Inspiratory Capacity (IC)
94
- 2300 ml - happens before you inhale or after you exhale (or before tidal volume inspiration or tidal volume expiration) - Remains in lungs at end of normal expiration - ERV+RV
Functional Residual Capacity (FRC)
95
- 4600 ml - maximum amount of air that you can inhale or exhale - Max that can be expelled after max inspiration then max expiration - IRV+VT+ERV or IC+ERV
Vital Capacity (VC)
96
- 5800 ml or approx 6L - maximum volume to which the lung can be expanded with the greatest possible effort - Maximum volume that lungs can hold at a given time - VC+RV or FRC+IC
Total Lung Capacity (TLC)
97
- marker for lung function - if its decrease, you already have a lung failure - alveolar pressure = atmospheric pressure (no air is coming in and out of the lungs) - also known as equilibrium volume
Functional Residual Capacity (FRC)
98
Spirometry
- Forced Vital Capacity (FVC) - Forced Expiratory Volume in 1 second (FEV1) - FEV1/FVC - Average midmaximal expiratory flow rate (FEF25-75)
99
- is the total volume of air that can be forcibly expired | after a maximal inspiration
Forced vital capacity (FVC)
100
The volume of air that can be forcibly expired in the | first second is called __.
Forced Expiratory Volume in 1 second (FEV1)
101
- measure severity of certain lung condition | - used to differentiate Obstructive Pulmonary Disease and Restrictive Pulmonary disease
Spirometry
102
Obstructive Pulmonary Disease vs Restrictive Pulmonary disease
Obstructive Pulmonary Disease - problems with expiration; can cause expiratory wheezing; COPD, Asthma Restrictive Pulmonary disease - problems with inspiration; Interstitial Lung Disease like fibrosis
103
In a normal person, __ is approximately 0.8, meaning that 80% of the vital capacity can be expired in the first second of forced expiration
FEV1/FVC
104
In a patient with an __, both FVC and FEV1 are decreased, but FEV1 is decreased more than FVC is. Thus, FEV1/FVC is also decreased, which is typical of airway obstruction with increased resistance to expiratory airflow
obstructive lung disease
105
In a patient with a __, both FVC and FEV1 are decreased but FEV1 is decreased less than FVC is. Thus, in fibrosis, FEV1/FVC is actually increased
restrictive lung disease
106
obstructive lung disease
FEV1: Decreased More FVC: Decreased FEV1/FVC: Decreased
107
restrictive lung disease
FEV1: Decreased FVC: Decreased More FEV1/FVC: Normal or Increased
108
Total amount of new air moved into the respiratory passages per minute
Minute Respiratory Volume
109
Minute Respiratory Volume (MRV)
Minute Respiratory Volume (MRV) = Tidal Volume x Respiratory Rate * Normal MRV = 0.5L x 12 bpm = 6L/min * Max MRV = 4.6L x 50 bpm = 230L/min
110
- Rate at which new air reaches the alveoli | - One of the major factors in determining the concentration of Oxygen and Carbon Dioxide in the Alveoli
Alveolar Ventilation
111
Areas where there is no gas exchange is referred to as __
Dead Space
112
- Normal and physiologic - Air in normal non-conducting areas (from nose to terminal bronchiole) - Normal value: 150 ml
Anatomic Dead Space Volume
113
- Amount of air in the alveoli that are not capable of gas exchange - Air in abnormal non-conducting alveoli - Normal value: 0 ml
Alveolar Dead Space Volume
114
- Sum of Anatomic Dead Space Volume + Alveolar Dead Space Volume
Physiologic Dead Space Volume
115
Alveolar Ventilation
VA = RR x (Tidal Volume – Physiologic Dead Space Volume)
116
- Air flows through the airways when pressure difference is present between the two ends - Air only flow from high pressure to low pressure
Airflow in Airways
117
Determinants of Air Flow Rate
1. Pattern of Gas flow | 2. Resistance to airflow by airways
118
Pattern of Gas flow
1. Laminar Flow | 2. Turbulent Flow
119
- Parallel to walls (fastest at the center; slowest at the edges - Present at low flow rates - Described by Poiseuille’s Equation
Laminar Air Flow
120
- random, disorderly, disorganized air flow
Turbulent Air Flow
121
Airway Resistance
Major site of resistance: large bronchi | Approximately 1 cm H20/L/ sec
122
Airway Resistance: FACTORS
1. Lung volume - Decreased by airway mucus, edema and bronchiolar constriction 2. Density and viscosity of inspired gas - E.g. inc density of gases in scuba diving
123
- Caused by the constant impact of moving molecules against a surface - directly proportional to the concentration of the gas molecules
PRESSURE
124
- In a mixture of different gases, it is the pressure caused by each gas alone
PARTIAL PRESSURE
125
DALTON’S LAW OF PARTIAL PRESSURE’S
Partial Pressure = Total pressure x Fractional gas concentration
126
Physics of Diffusion and Partial Pressures: EXAMPLE
Atmospheric pressure = 760mmHg Oxygen =21% of atmosphere Nitrogen = 79% of atmosphere Partial Pressure of Oxygen(PO2) in the Atmosphere 760x.21 = 159.6 Partial Pressure of Nitrogen (PN2) in the Atmosphere 760x.79 = 600.4
127
HENRY’S LAW
Partial Pressure = Concentration of Dissolved Gas/Solubility Coefficient
128
SOLUBILITY COEFFIECIENT
``` CO2 = 0.57 (has a higher solubility coefficient) O2 = 0.024 CO = 0.018 Nitrogen =0.012 Helium = 0.008 ```
129
Fick’s Law of Gas Diffusion
D = Delta P x A x S -------------------- d x √MW ``` Where: D = Diffusion Rate Delta P = Partial Pressure Difference between two ends A = Cross-Sectional Area S = Solubility of Gas d = distance of diffusion MW = Molecular weight ```
130
(Fick’s Law of Gas Diffusion) Diffusion is directly proportional to
1. Partial pressure difference between two ends 2. Cross-sectional area (the larger the cross sec area, the greater the diffusion) 3. Solubility of Gas (the greater the solubility, the greater the diffusion)
131
(Fick’s Law of Gas Diffusion) Diffusion is inversely proportional to
1. Distance of diffusion (the longer the distance, the slower the diffusion rate) 2. Molecular weight (the larger the MW, the slower the diffusion)
132
DIFFUSION COEFFICENT
DIFFUSION COEFFICENT = S/√MW D = Delta P x A x Diffusion Coeff --------------------- d
133
Rate at Which Alveolar Air is Renewed by Atmospheric Air
- Only 350ml on new air is brought to the alveoli - FRC = 2300ml - It will take more than 16 breaths to replace most of the alveolar air * Prevents sudden changes in gas concentrations in the blood
134
Factors Affecting Diffusion in the Respiratory Membrane
1. Thickness of the membrane - affected by Edema, Fibrosis 2. Membrane surface area - affected by Emphysema 3. Diffusion coefficient of the gas - depends on the gas’ SOLUBILITY in the membrane and inversely on the square root of the gas’ molecular weight CO2 > O2 > N2 4. Pressure difference of a gas
135
- the ability to exchange gas - ability of the respiratory membrane to exchange gas between the alveoli and the pulmonary blood - Volume of gas that will diffuse through the membrane each minute for a pressure difference of 1 mmHg
Diffusing Capacity
136
DIFFUSING CAPACITY (O2)
O2– normal is 21 ml/min/mmHg, if exercising, 65 ml/min/mmHg | *during exercise, the diffusing capacity will increase three times the normal value
137
DIFFUSING CAPACITY (CO2)
CO2 – normal is 400-450 ml/min/mmHg, if exercising, 1200-1300 ml/min/mmHg * higher than Oxygen because CO2 is more soluble * during exercise, the diffusing capacity will increase three times the normal value
138
Factors that increase Diffusing Capacity during Exercise:
1. Opening of dormant capillaries | 2. Greater V/Q ratio
139
Another condition in which the diffusing capacity will increase three times the normal value
High Altitude
140
V/Q Ratio and Alveolar Gas Concentration
- The lung areas are NOT made equal | - Different areas have different ventilation, different perfusion
141
Site of Highest Ventilation (V):
BASE
142
Site of Highest Perfusion (Q):
BASE (because of gravity)
143
Site of Highest Ventilation-Perfusion Ratio (V/Q):
APEX
144
Normal Ventilation-Perfusion Ratio
80% or .8
145
(V/Q Ratio and Alveolar Gas Concentration) | If VA/Q = 0
- VA = 0 - occurs during mucus plug; no air flow - Air in the alveoli equilibrates with blood O2 and CO2 - termed for Physiologic Shunt (shunted towards better ventilated area)
146
(V/Q Ratio and Alveolar Gas Concentration) | If VA/Q = infinity
- Perfusion = 0 - happen in Pulmonary Embolism; no blood flow =no gas exchange - Air in the alveoli equilibrates with humidified inspired air - Physiologic Dead Space (no gas exchange)
147
Abnormalities of V/Q Ratio: UPRIGHT POSITION
Top of the lung: moderate degree of physiologic dead space (low perfusion) Bottom of the lung: moderate degree of physiologic shunt (low ventilation)
148
- Has areas with both serious physiologic dead space (inadequate flow in some areas) and serious physiologic shunt (obstructed small bronchioles)
Chronic Obstructive Pulmonary Disease (COPD)
149
(Oxygen Transport in the Blood) | O2 is transported as:
1. Freely-dissolved O2 in the plasma (2%) | 2. Bound to Hemoglobin (98%)
150
Oxygen Transport in the Blood
Oxyhemoglobin: with bound O2 Deoxyhemoglobin: without bound O2
151
Hemoglobin is ideal for transport of O2 and CO2
1. Positive cooperativity happens for Oxygen | 2. CO2 participates in the Haldane effect and Bohr Effect
152
Total amount of O2 carried in blood including bound and dissolved O2
O2 Content of Blood
153
O2 Content of Blood
O2 content = (hemoglobin concentration x O2 binding capacity x % saturation) + dissolved O2
154
Enable to pick up oxygen easily especially when there is high level of oxygen like in the lungs
Positive cooperativity
155
- Sigmoidal in shape (rapid pick up of oxygen in high oxygen area) * PO2 of 25 mmHg: 50% saturated (P50) * PO2 of 40 mmHg: 75% saturated (mixed venous blood) * PO2 of 100 mmHg: almost 100% saturated (arterial blood) - Exhibits Positive Cooperativity * Binding of first O2 molecule increases affinity for second O2 molecule and so forth O2-HgB Dissociation Curve
O2-HgB Dissociation Curve
156
(O2-HgB Dissociation Curve) | Shift to the RIGHT
“CABET, do the RIGHT thing, LET GO” ``` CO2 Acidosis 2,3 BPG Exercise Temperature ```
157
- For a given partial pressure of oxygen, mas mababa ang saturation - Increase unloading of oxygen that's why the saturation is low - Decrease binding of oxygen to hemoglobin - faster unloading of oxygen = will go to the starving tissues that needs oxygen - happen during HYPOXIA
Shift to the RIGHT
158
- For a given partial pressure of oxygen, the higher the saturation; increase binding of oxygen to hemoglobin - eg Fetal Hemoglobin; Carbon Monoxide Poisoning
Shift to the LEFT
159
pH of 7.4 to 7.2
Shift to the Right
160
Decrease CO
Shift to the RIGHT
161
Decrease CO2
Shift to the LEFT
162
Increase pH
Shift to the LEFT
163
Increase CO
Shift to the LEFT
164
Increase CO2
Shift to the RIGHT
165
Increase Acidity/Low pH
Shift to the RIGHT
166
Increase in Alkalinity
Shift to the LEFT
167
Decrease in Alkalinity
Shift to the RIGHT
168
pH 7.4 to 7.6
Shift to the LEFT
169
Fever
Shift to the RIGHT
170
Hyperventilation
Shift to the LEFT due to less carbon dioxide
171
CO2 is transported in the blood in 3 ways:
1. As HCO3- (90%) CO2 + H2O ↔ H2CO3 ↔ H+ + HCO3- 2. Freely-dissolved in plasma (5%) 3. CarbaminoHemoglobin (3%)
172
- Increased CO2/H+ causes UNLOADING OF OXYGEN from Hemoglobin (shift to the R of the O2-HgB dissociation curve) - Occurs in Body Tissues
BOHR EFFECT
173
- Increased O2 causes UNLOADING OF CARBON DIOXIDE from Hemoglobin (shift to the R of the CO2-HgB dissociation curve) - Occurs in the Lungs
HALDANE EFFECT
174
Components for Control of Breathing
- Cerebral Cortex - Control Centers in the Midbrain and Pons - Central and Peripheral Chemoreceptors - Mechanoreceptors - Respiratory Muscles
175
- Can override the autonomic brainstem centers - Voluntary Hyperventilation * Dec PaCO2 increases pH LOC - Voluntary Hypoventilation (breath-holding) * Dec PaO2, Inc PaCO2 decreases pH LOC - period of prior hyperventilation can prolong the duration of breath-holding
Cerebral Cortex
176
- Creates the Basic Respiratory Rhythm | - contains the Dorsal Respiratory Group (DRG), Ventral Respiratory Group (VRG) and Central Chemoreceptors
Medulla
177
- Modify the output of the Respiratory center - Modifies the Basic Respiratory Rhythm - contains the Apneustic and Pneumotaxic centers
Pons
178
- Inspiratory Center; Control Basic Rhythm; For Normal Inspiration; can be modified by apneustic and pneumotaxic centers
Dorsal Respiratory Group (DRG)
179
- Override Mechanism during exercise; for Forced Inspiration and Respiration
Ventral Respiratory Group (VRG)
180
- Found in the Lower Pons | - prolongs the duration of inspiration >> decrease Respiratory Rate
Apneustic Center
181
- Found in the Upper Pons | - Decreases the duration of the inspiration >> increases the Respiratory Rate
Pneumotaxic centers
182
- Found in the ventral medulla | - Respond directly to CSF H+ (increases RR)
Central Chemoreceptors
183
- Responds MAINLY to PaO2
Peripheral Chemoreceptors
184
Chemoreceptors
Central Chemoreceptors = CSH H+ Peripheral Chemoreceptors = Pang Low Oxygen (O2)
185
- Diseases that will decrease the RR: causes __ - accumulation of Oxygen in the blood (e. g. sedative overdose)
Respiratory Acidosis
186
- Diseases that will increase the RR: causes __ - less carbonic acid in the blood and associated with hypocalcemia (e. g.panic attacks)
Respiratory Alkalosis
187
In metabolic acidosis, the compensation is __
Tachypnea
188
In metabolic alkalosis, the compensation is __
Bradypnea
189
(Mechanoreceptors) - Stimulated by Lung Distension - Initiates Hering-Breuer Reflex that decreases Respiratory Rate by prolonging expiratory time
Lung Stretch Receptors
190
(Mechanoreceptors) - Stimulated by Limb Movement - Causes anticipatory increase in Respiratory Rate during Exercise - the moment you move your limbs, you Respiratory Rate will immediately go up
Joint and Muscle Receptors
191
Protection reflex that prevents the overinflation of the lungs
Hering-Breuer Reflex
192
(Mechanoreceptors) - Stimulated by Noxious chemicals - Causes bronchocontriction and increases the Respiratory Rate
Irritant Receptors
193
(Mechanoreceptors) - Found in “juxtacapillary” areas - Stimulated by pulmonary capillary engorgement - Causes rapid shallow breathing and responsible for the feeling of dyspnea (e.g. in L-sided heart failure)
J Receptors

Physiology Module (8 decks)

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