Respiratory Flashcards
(207 cards)
1
Q
How does bronchodilation happen in conducting airways?
A
Relaxing of smooth muscle
2
Q
What is laminar flow in a vein or artery?
A
Fluid does not touch walls of vessel
3
Q
What is turbulent flow in a vein or artery?
A
At walls, excited, eddies, radial traction
4
Q
What is radial traction?
(think alveoli and lungs)
A
Elastic fibres of the surrounding alveoli pull on the walls of small airways and hold them open.
The higher the elastic recoil of the lungs, the greater the radial traction will be.
Radial traction helps to prevent airway collapse in expiration.
5
Q
What is an eddy?
A
Eddy currents are loops of electrical current induced within conductors by a changing magnetic field in the conductor’s vicinity according to Faraday’s law of induction. Eddy currents flow in closed loops within conductors, in planes perpendicular to the magnetic field.
6
Q
What is an eddy in turbulent flow in a blood vessel?
A
Eddy is the swirling of a fluid and the reverse current created when the fluid is in a turbulent flow regime.
7
Q
What is dyspnoea?
A
Feeling of breathlessness
Sensation of laboured breathing
8
Q
Hyperventilation (+ examples)
A
Too much breathing
Breathing in excess of metabolic needs
e.g. asmtha, panic attack
9
Q
Hyperpnia (+ examples)
A
Elevated breathing
Increased breathing that matches the metabolic needs
Reason behind it e.g. faster breathing in exercise to pump blood around heart faster for increased demand
10
Q
Tachypnoea
A
Elevated frequency
Increased respiratory rate above normal (>20 breaths per minute)
Often shallow, rapid breathing
11
Q
Hypoventilation
A
Too little breathing
Breathing that is insufficient to meet the metabolic needs
e.g. constructive airflow
12
Q
Apnoea
A
No breathing - no airflow
An absence of airflow due to lack of respiratory effort or airway obstruction
13
Q
Hypoxia
A
Too little oxygen
14
Q
What type of gas is CO2 in the respiratory process?
A
- waste
- acidic
- buffer system
15
Q
What is involved in the respiratory control centre? (2)
A
Sensors - relay relevant information to the central control sites in the brain stem regarding respiratory homeostasis
Effectors - breathing adjusted through a change in the central rhythm (rate) and the neural activity of the effectors
16
Q
What is homeostasis?
A
Any self-regulating process by which biological systems tend to maintain stability while adjusting to conditions that are optimal for survival
17
Q
Thermoreceptors
A
Heat sensors
18
Q
Chemoreceptors
A
Chemical sensors
19
Q
Hypoventilation examples
A
- central
- spinal injury; motor neuron dysfunction
- neuromuscular disorders
- obesity
- airway obstruction
- obstructive diseases: COPD
- restricive diseases: Pulmonary Fibrosis
20
Q
Hypercapnia
A
Abnormally elevated levels of CO2
Hypoventilation & Lung disease
Alveolar hyperventilation clears CO2
21
Q
What is alveolar hypoventilation?
A
Lung alveolus hypoventilation refers to insufficient ventilation in the lungs, resulting in:
- increased levels of carbon dioxide (PaCO2)
- decreased levels of oxygen (PaO2) in the blood.
22
Q
What is the result of Alveolar hypoventilation?
A
Respiratory acidosis
23
Q
What is a respiratory acidosis?
A
Respiratory acidosis is when your blood is acidic because your lungs can’t remove carbon dioxide.
24
Q
What is the result of alveolar hyperventilation?
A
Respiratory alkalosis
25
What is respiratory alkalosis?
pH level of blood rises as there is not enough Carbon Dioxide in the blood
26
What is OSAS?
Obstructive sleep apnoea syndrome
Affects ~1 billion people
27
What contributes to or is associated with OSAS?
- Recurrent airway obstruction
- Insulin resistance
- Metabolic dysfunction
- Cardiovascular dysfunction
- Hypersomnolence
- Neurocognitive dysfunction
28
What is hypersomnolence?
An inability to stay awake & alert during major waking episodes, resulting in periods of irrepressible need for sleep / unintended lapses into drowsiness or sleep
29
Hypopnea
> 10s reduction in airflow by >30% and >=3% oximetry desaturation or arousal on EEG channels
30
AHI
Number of apnoeas and hypopnoeas per hour of sleep/study time
31
ODI
number of Oximetery desaturations per hour of sleep/study time
32
RDI
Respiratory Disturbance Index
33
Circadian Rhythm
a rest activity cycle in time with the 24hr rotation of our earth
34
What does an auditory click elicit in sleep?
Deepening of cortical sleep
It is progressively harder to wake someone up as they go from shallow stage 1 to deep SWS sleep
As such it represents a state of relative brain shutdown
35
Is REM or non-REM sleep associated with dreaming?
REM
REM: Rapid Eye Movements
When you are dreaming your eyes flash backwards and forwards under closed eyelids
36
37
37
38
What is behind the cardiorespiratory response to hypoxia?
Carotid bifurcation
39
What is a result of carotid bifurcation hyperactivity?
- Hypertension
- Apnoea
40
What is apnoea?
When breathing starts and stops in sleep
no movement of the muscles of inhalation, and the volume of the lungs initially remains unchanged. Depending on how blocked the airways are, there may or may not be a flow of gas between the lungs and the environment.
can lead to more severe problems
41
What is carotid bifurcation?
The point where the common carotid artery divides into internal and external carotid arteries.
This point is located in the carotid triangle, at the level of the fourth cervical vertebra or laryngeal prominence.
42
What is a carotid body? And what does it respond to? (5)
The carotid body is a chemoreceptor located in the adventitia of the bifurcation of the common carotid artery.
Responds to:
- Glucose
- Insulin
- Hormones
- Cytokines
- Temperature
43
What are cytokines?
Signalling proteins that help control inflammation
44
What is the role of the brainstem in respiratory function?
It controls breath-by-breath function
(Rhythm & pattern)
45
What syndrome often presents with sleep apnoea?
Restless leg syndrome
46
What can be used to detect or monitor sleep apnoea?
Polysomnography
47
What is polysomnography?
Records your brain waves, the oxygen level in your blood, and your heart rate and breathing during sleep
48
CSF is a common abbreviation for...
Cerebral spinal fluid
49
PO2 stands for...
The partial pressure of oxygen
50
What is central apnoea?
Breathing repeatedly stops and starts during sleep.
Must last a min. of 10s
51
What is obstructive apnoea?
Breathing stops because the throat muscles relax and block the airway.
52
Less than how many incidences per hour of sleep is sub clinical for central apnoea?
5
53
How many incidences of central apnoea per hour of sleep is considered severe?
>30
54
Anatomical contributors to sleep apnoea? (3)
- Narrow
- Crowded
- Collapsible
55
Non-anatomical contributors to sleep apnoea? (3)
- Ineffective pharyngeal dilator muscle activity in sleep
- Low arousal threshold to airway narrowing
- Unstable control of breathing (high loop gain)
56
What is a risk of low lung volumes?
Intrapulmonary airway collapse
57
What does Fick's Law state for Respiratory Physiology?
Rate of gas transfer across a tissue or membrane is directly proportional to the difference in partial pressures of the gas on the two sides of the membrane.
58
Mechanics of breathing (2)
- Complianace
- Elastance
59
What is the most performance aspect of exercise limitation?
Work of breathing
60
How does the mechanics of volume change work in the lungs?
Neuromuscular action
61
How does the mechanics of pressure change work in the lungs?
Encouragement of flow
62
How does a terminal bronchiole differ from a respiratory bronchiole?
Terminal:
- no alveoli at microscopic level
- blood delivered to it to maintain it's structure
- no gas exchange (walls not thick enough)
Respiratory:
- respiratory epithelium condenses
- occasional alveoli
- at walls: cul-de-sac of loads of alveoli (exponential rise in surface area for gas exchange)
63
What is compliance in relation to the lung?
Stretchiness
64
How is compliance related to elastance?
Reciprical values
65
What is elastance in relation to the lung?
Intrinsic recoil of lungs (and chest wall)
66
What is a communicable disease?
An illness caused by pathogenic microorganisms such as bacteria, viruses, fungi, parasites or prions.
Can be transmitted from one person, animal, or object to another, leading to the spread of infection within a community or population.
67
What is the infection pathway of a communicable disease? (6)
- Infectious agents
- Resevoirs
- Portals of exit
- Modes of transmission
- Portals of entry
- Susceptible host
68
In the infection pathway, what is an infectious agent? Give examples.
Microorganism capable of causing disease or illness
e.g. Bacteria, fungi, parasites, prions
69
In the infection pathway, what is a reservoir? Give examples.
Place in which infectious agents live, grow, and reproduce.
e.g. people, water, food
70
In the infection pathway, what is are portals of exit? Give examples.
Ways in which infectious agent leaves the reservoir.
e.g. blood, secretions, excretions, skin
71
What is the difference between a secretion and an excretion?
Excretion: elimination of waste material
Secretion: transport of material from one part of the body to another
72
In the infection pathway, what is a mode of transmission? Give examples.
Way in which the infectious agent spreads from the reservoir to susceptible host
e.g. physical, contact, droplets, airborne
73
In the infection pathway, what is are portals of entry? Give examples.
Ways in which the infectious agent enters the susceptible host
e.g. mucous membrane, resp system, dig system, broken skin
74
What is the mucous membrane?
The moist, inner lining of some organs and body cavities (such as the nose, mouth, lungs, and stomach).
Glands in the mucous membrane make mucus (a thick, slippery fluid)
75
In the infection pathway, what is a susceptible host? What makes a host susceptible?
Individuals that may have traits affecting their susceptibility and severity of disease
e.g. immune deficiency, diabetes, burns, surgery, age
76
Modes of transmission in a healthcare setting (4)
- Hands
- Equipment
- Inhalation
- Ingestion
77
Name some healthcare associated infections. (9)
- Norovirus (vomiting bug)
- MRSA
- C.diff
- CPE
- ESBLs (superbugs)
- VRE (superbug)
- IV Line infection
- Urinary catheter infection
- C.auris (superbugs)
78
WHO 5 Moments for Hand Hygiene
1. Before touching a aptient
2. Before a procedure
3. After a procedure or body fluid exposure risk
4. After touching a patient
5. After touching a patient's surroundings
79
Steps for putting on PPE (5)
1. Hand hygiene
2. Plastic apron
3. Surgical mask
4. Protective eyewear
5. Gloves
80
Steps for taking off PPE (5)
1. Remove gloves
2. Hand hygiene
3. Remove eye wear / apron / surgical mask
4. Dispose of waste
5. Hand hygiene
81
Chain of transmission of influenza (8)
1. Virus shedding
2. Exposure
3. Inhalation
4. Attachment
5. Entry
6. Spread
7. Symptoms develop
8. Shedding
82
Respiratory reSIStance (as measured by oscillometry) Rrs
Degree of obstruction / opposition to flow across the tracheobronchial tree
83
Respiratory reACTance (as measured by oscillometry) Xrs
Measure of the inertance/elastance of the stimulated airways & alveoli
84
Is respiratory resistance or reactance more sensitive to changes in the peripheral part of the airways?
Respiratory reactance
85
What type of airway pathology is respiratory resistance particularly sensitive to?
Central Airway Pathology
86
What 2 types of sensors are in a oscillimetry machine?
Flow & Pressure
87
What frequency range is used in oscillometry testing?
4/5 Hz up to 35/50 Hz
88
What type of patients requires higher testing frequencies (~35 Hz)?
Children
89
What is the variable measurement in an oscillometry test? And what is its relationship to resistance?
Pressure
Directly proportional
90
Is there a phase difference when flow and pressure are in phase?
No
91
What is represented by the length of a flow/pressure line in the real/imaginary plane?
Amplitude
92
What is represented by the angle of a flow/pressure line to the real axis in the real/imaginary plane?
Phase
93
Is inertance positive or negative in the imaginary axis?
Positive
94
Is inertance positive or negative in the imaginary axis?
Positive
95
Is elastance positive or negative in the imaginary axis
Negative
96
Is resistance represented by the real or imaginary axis?
Real
97
Is resistance represented by the real or imaginary axis?
Real
98
Is reactance represented by the real or imaginary axis?
Imaginary
99
Is resistance the in-phase or out-of-phase part of impedance?
In-phase
100
Is reactance the in-phase or out-of-phase part of impedance?
Out-of-phase
101
What does it mean for oscillometry and respiratory flow to be in-phase?
Pressure and flow are varying at the same frequency.
102
What is the relation between the magnitude of a vector and the amplitude of oscillation?
Length of vector = peak amplitude of oscillation
103
Vector division in polar form. How does it work?
Divide the magnitudes.
Subtract the phase angle.
104
Why does the resistance rapidly increase when f < 5 Hz? (and reactance rapidly decrease)
Due to dominance of the mechanical properties of the lung (tissue viscoelasticity) and chest wall (elastance)
105
At f > 5 Hz, what happens to the resistance and reactance?
Resistance is largely independent of frequency.
Reactance has a positive frequency dependence. Apparent elastance decreases, reactance becomes less negative and inertia dominates.
106
What is resonant freqeuncy? What does this look like on a graph in the Re-Im plane?
Xrs = 0
Curve cross real axis (imaginary axis = 0)
107
Is reactance positive or negative below fres? Why?
Negative.
Dominated by apparent elastance.
108
What is resonant frequency in healthy adults?
8 - 12 Hz
109
Is reactance positive or negative above fres? Why?
Positive.
Dominated by apparent inertia of gases and tissues.
110
Is Ax (area of reactance) dominated by elastance or inertance?
Elastance
111
Does Ax increase or decrease in peripheral lung disease?
Increase
112
What indicates that there is greater elastance than inertance? (2)
1. Angle of flow > angle of pressure
2. Flow first peak (crosses Im first)
113
What indicates that elastance = inertance? What does this mean?
In-phase
It was measured at fres
114
What is the Z score?
How well estimated value compares with real value
115
Uses of oscillometry?
To quantify bronchodilator responses, and in bronchial challenge testing.
116
What is the effect of volume history on oscillometry?
Volume history potentially affects impedance measurements in
individuals with airways disease and in healthy subjects during
bronchial challenge testing
117
What is the difference between obstructive and restrictive lung diseases?
OLD: restriction of airflow during expiration
RLD: restriction of airflow during expiration
118
What respiratory diseases are classed as obstructive lung diseases?
- COPD (chronic obstructive pulmonary disease)
- Cystic Fibrosis
- Asmtha
119
What respiratory diseases are classed as restrictive lung diseases?
- Sarcoidosis
- Pulmonary fibrosis
- Insterstitial lung disease
120
What are risk factors for COPD? List at least one factor from each of development factors, socioeconomic factors, and noxious exposures.
- premature birth
- asthma
- maternal, pre-natal, and childhood exposures
- ageing
- access to healthcare
- socioeconomic disadvantage
- pollution and biomass combustion
- tobacco smoke
121
COPD
persistent airflow limitation that is not fully reversible, typically caused by long-term exposure to harmful irritants, most commonly cigarette smoke.
- chronic bronchitis
- emphysema
122
Chronic bronchitis
inflammation and mucus buildup in the airways
123
Emphysema
destruction of alveoli and loss of lung elasticity, leading to difficulty with expiration
124
COPD Symptoms (4)
- chronic cough
- dyspnea (shortness of breath)
- wheezing
- excessive mucus production, which worsen over time
125
Cystic Fibrosis
Congenital lung disease - mutation in CFTR gene
production of thick, sticky mucus in the airways, leading to recurrent lung infections, chronic inflammation, and progressive airway obstruction.
very low immune system
126
How long is a person with CF expected to survive? (Based on medium in Ireland)
51 y/o
127
What gene is affected in CF patients and how does this impact the patient?
CFTR
This gene regulates the movement of chloride ions in and out of cells, which is crucial for maintaining the balance of salt and water on epithelial surfaces, like those lining the lungs.
- impaired chloride ion transport
- disrupts the normal salt and water balance in the airway lining
- mucus that lines the respiratory tract becomes thick, sticky, and dehydrated.
128
What is observed in FEV1 capacity, FVC, and RV in CF patients?
FEV1: Reduced FEV1 (airway obstruction)
FVC: Low FEV1/FVC ratio (difficulty exhaling)
RV: Increased residual volume (air trapping and reduced lung elasticity)
129
Hypercapnia
High CO2 levels
130
Asthma
OLD characterized by hyperactive airways
- triggered by allergens or irritants, causing bronchoconstriction
- airway inflammation that can be relieved with medications.
131
What lung function tests may be used in diagnosing OLD?
- Sprirometry
- Peak expiratory flow (PEF) measurement
- Exhaled Nitric Oxide fraction
- Bronchial challenge testing
132
In using a peak expiratory flow measurement over a 2-week period, what % supports an asthma diagnosis?
> 20%
133
In a spirometry test, what FEC/FVC ratio supports an asthma dianosis?
Lower Limit of Normal (LLN) < 0.75
134
Bronchial challenge testing is performed in secondary care when a diagnosis of asthma could not be confirmed in primary care. What amount of methacholine (PC20M) or histamine (mg·mL−1) supports a diagnosis of asmtha?
<8 mg·mL−1 methacholine (PC20M) or histamine in steroid-naïve patients
<16 mg·mL−1 in a patient receiving regular inhaled corticosteroids
135
How do asthma patients respond after the use of a dilator?
improved FEV1
136
What is the key pathophysiological feature of OLD?
increased resistance to airflow caused by
- inflammation
- mucus hypersecretion
- structural changes in the airways.
137
How can OLD be managed?
- reducing inflammation (with inhaled corticosteroids)
- relaxing airway muscles (with bronchodilators)
- improving lung function with lifestyle changes and therapies like pulmonary rehabilitation.
138
People of what ethnic background are prone to Restrictive Lung Diseases?
African-Americans (35.5 cases per 100,000)
139
What leads to hypoxemia?
A reduction in the lung’s ability to take in oxygen and eliminate carbon dioxide.
140
What characteristics are associated with RLD?
- decreased lung compliance
- lungs become stiffer and require more effort to expand
141
Intrinsic vs Extrinsic RLD
Intrinsic: Primarily involve diseases affecting lung parenchyma, such as interstitial lung disease (ILD), pulmonary fibrosis, and sarcoidosis, leading to fibrosis, inflammation, and scarring of lung tissue.
Extrinsic: Conditions external to the lung, such as obesity, kyphoscoliosis, pleural effusions, and neuromuscular disorders
142
What is pleural effusion?
Fluid accumulation in the pleural space compresses lung tissue, leading to a restrictive pattern with decreased total lung capacity (TLC) and vital capacity (VC), functional residual capacity (FRC) and forced vital capacity (FVC).
143
What effect does fluid accumulation in the pleural space have on the lung properties?
Decreased
- total lung capacity (TLC)
- vital capacity (VC)
- functional residual capacity (FRC)
- forced vital capacity (FVC)
144
What happens in the lung as a result of pleural effusion?
- fluid layer between the lung and chest wall disrupts ventilation-perfusion matching, leading to hypoxemia
- lung compression from the effusion increases the effort required to inflate the lungs, leading to dyspnea
145
Hypoxemia
Low O2 levels
146
What is a pneumothorax?
Lung collapse & impaired ventilation
Air in the pleural space during a pneumothorax disrupts the negative pressure needed to keep the lung inflated
147
Name the 3 types of Interstitial lung disease and give examples of each.
- exposure: drug induced, occupational, environmental
- autoimmune: Rheumatoid Arthritis, Scleroderma, Polymyositis, Dermatomyositis
- idiopathic: Idiopathic pulmonary fibrosis (IPF), Non-specific interstitial pneumonia (NSIP), Cryptogenic organizing pneumonia (COP)
148
What does idiopathic mean?
Unknown cause
149
What is a common physical characteristic of Interstitial Lung Disease? (2)
inflammation & fibrosis (scarring) of the lung interstitium, affecting the space around the alveoli.
150
If a patient presented with restrictive lung pattern on PFTs, showing reduced forced vital capacity (FVC), total lung capacity (TLC), and diffusion capacity for carbon monoxide (DLCO), indicating impaired gas exchange, what type of lung disease might they be diagnosed with?
Interstitial Lung Disease
151
Anti-inflammatory & immunosuppressive drugs, and anti-fibrotic therapies may be used to treat what form of lung disease?
Interstitial Lung Disease
152
In what form of ILD might a patient present with a restrictive lung disease pattern, with reduced lung volumes, including total lung capacity (TLC) and forced vital capacity (FVC), while the FEV1/FVC ratio remains normal or increased?
Idiopathic pulmonary fibrosis (ILD)
153
How does Idiopathic pulmonary fibrosis (ILD) initiate?
abnormal activation of fibroblasts, which proliferate and produce excessive collagen, leading to the formation of fibrotic tissue in the lungs
154
A farmer who is often exposed to environmental antigens such as mold spores, animal proteins, and organic dust has a high probability of developing what from of ILD?
hypersensitivity pneumoitis (HP)
155
In what from of restrictive lung disease would alveolar inflammation and granuloma formation in the lung parenchyma be observed, as well as enlargement of the lymph nodes?
Sarcoidosis
156
List the 6 areas where restrictive and obstructive lung diseases differ.
- Airflow Limitation vs. Lung Volume Reduction:
- FEV1/FVC Ratio:
- Total Lung Capacity (TLC)
- Pathophysiology: Airway Narrowing vs. Stiffening:
- Breathing Mechanics: Expiratory vs. Inspiratory:
- Gas Exchange
157
Tidal Volume (Vt)
volume of gas entering the lungs in each breath during quiet breathing
measured by spirometry
158
Forced Vital Capacity (FVC)
If a person subjects takes a maximal inspiration followed by a forced maximal expiration, the FVC is the max amount of air you can exhale after maximum inhalation (~80% total lung volume))
measured by spirometry
159
Residual Volume (RV)
Volume of gas remaining in lungs after FVC
160
Total Lung Capacity (TLC)
Volume of gas in the lung after a deep breath
161
Explain the mechanism and muscles involved in the inspiration part of the respiratory cycle.
Contraction of the diaphragm forces abdominal contents downwards expanding the abdomen and thorax outward
- external intercostals: pull the ribs forwards and upwards, does <20% work
- accessory muscles: scalene lifts the first 2 ribs and sternocleidomastoids elevate the sternum (exercise & respiratory disease)
- contraction of the inspiratory muscles expand the thorax outward, creating a more negative intrapleural pressure (Ppl) which pulls on the lungs
- as lungs inflate, alveolar pressure drops below atmospheric pressure, drawing air into the lungs
- process continues until lung volume reaches a point where maximal F exerted by the inspiratory muscles = lung and chest wall elastic recoil causing inspiratory flow to stop
162
Vital Capacity (VC)
VC = TV + IRV + ERV,
IRV = inspiratory reserve volume
ERV = exspiratory reserve volume
Vital capacity is the volume of gas from maximum inspiration to maximum expiration.
163
What is the difference between FVC and VC?
FVC = forced, volume of air exhaled with maximal effort from inspiration
VC = relaxed form of FVC
164
At what point in the respiratory cycle does inspiration stop?
When lung volume Fmax = lung & chest elastic recoil
165
What happens to the lung and chest wall at the end of the respiration cycle?
The lung and chest wall are elastic and tend to return to their equilibrium positions.
166
What does relaxation of the respiratory muscles do to the lung and chest wall?
Relaxation of the respiratory muscles causes an inward elastic recoil of the lung and chest wall.
167
Functional Residual Capacity (FRC)
Volume of gas remaining in the lung upon reaching the relaxation volume (Vr) or at the end of tidal expiration
168
At what point in the respiratory cycle does inward lung recoil equal the outwards chest wall recoil?
Functional Residual Capacity
169
What muscles do 80% of the work in the respiratory process?
Internal muscles, mainly diaphragm
170
What muscles are involved in the respiratory cycle?
Internal muscles, mainly diaphragm and external intercostals
171
At what point in the respiratory cycle does alveolar pressure = atmospheric pressure?
Functional Residual Capacity
172
What is the avg pleural pressure?
-5 cm H2O
173
In the supine position, what happens to FRC?
reduced FRC
abdominal contents are displaced towards the chest wall
174
What are the most important muscles in expiration?
Abdominal wall muscles
(Rectus abdominis, internal and external oblique muscles and transverse abdominis)
175
What happens to intraobdominal pressure during expiration?
Raised
Abdominal wall muscles raise intra-abdominal pressure pushing diaphragm upwards
176
What happens to intra-thoracic volume during expiration?
Decreased
Internal intercostal muscles assist expiration by pulling the ribs downwards and inwards
177
What techniques can be used to measure TLC, RV, and FRC?
- gas dilution
- body plethysmography
178
Body plethysmography
Measures the total volume of gas in the lung, including any that is trapped behind closed airways
Consists of a large, airtight box, like a telephone booth, where the subject sits
179
Helium dilution
Helium virtually insoluble in the blood
Subject is asked to inhale and exhale in a closed-circuit spirometer containing a known concentration of helium and oxygen
180
Name the 2 regions of the lungs
- Conducting
- Respiratory (acinar)
181
Why does the left lung have 2 lobes whereas the right lobe only has 3?
Heart is where middle left lobe would be
182
Ventilation
Total volume of gas exchanged from atmosphere and the lung in minute
183
Name the 3 lobes of the right lung
Superior, middle, inferior
184
How to exhale more CO2? (2)
- increase TV
- increase respiratory rate
185
The conducting zones of the lungs consist of: (3)
Nose to Bronchioles
- Bronchi
- Bronchioles
- Terminal Bronchioles
Path for conduction of inhaled gases
186
The respiratory zones of the lungs consist of:
- Respiratory Bronchioles
- Alveolar ducts
- Alveolar sacs
Gas exchange takes place
187
What is the pulmonary dead space?
No gas exchange occurs in the dead space
Concentration of CO2 in expired gas comes only from 𝑉 ̇A
188
What is a common critical lung volume value?
50-60%
189
Lung compliance
Stiffness of lungs (curve on Volume vs Pressure graph for TLC)
Low lung compliance in COPD and ILD (less stretchy)
190
Dynamic hyperinflation
can't get all air out
191
192
What is the key difference between aerobic and non-aerobic respiration?
Aerobic: OXYGEN
Anaerobic: NO Oxygen
193
What is the key difference between aerobic and non-aerobic respiration?
Aerobic: OXYGEN
Anaerobic: NO Oxygen
194
What are some key characteristics for aerobic respiration? (4)
Uses O2
Efficient way of releasing energy from food
Complete breakdown of glucose
2 stages:
- stage 1 is anaerobic and takes place in cytosol of cell, aka glycolysis
- stage 2 id aerobic and takes place in mitochondria of cell, Krebs cycle and electron transport
195
Mechanisms of airflow in asmtha (3)
- Bronchoconstriction by airway muscle.
- Obstruction of airflow by intraluminal mucus.
- Inflammation and remodeling of the airway wall.
196
Mechanisms of airflow in COPD (3)
- Mucus hypersecretion.
- Abnormal bronchiolar (small airways) tissue repair.
- Alveolar wall destruction.
197
Name 3 types of bronchodilator drugs
- Beta-2 agonists.
- Anticholinergics.
- Methylxanthines.
198
By what mechanism do bronchodilator drugs work?
Relaxation of airway smooth muscle
199
Name 3 types of anti-inflammatory drugs
Corticosteroids.
Biologics (Anti-IGE, Anti-IL-5, and Anti IL-4 monoclonal antibodies)
Leukotriene Modifiers.
200
Targeted therapy in cystic fibrosis is is directed towards...
CFTR protein (Chloride channel) function restoration.
201
How can OLD be managed?
- reduce inflammation
- relax airway muscles
- improve lung function
202
What is OLD?
AIrflow limitation due to airway narrowing or obstruction
Difficult to fully exhale
203
Key features of OLD (3)
- increased resistance to airflow caused by inflammation
- mucus hypersecretion,
- structural changes in the airways
204
General OLD Symptoms (7)
Shortness of breath
Exertional dysnpnea
Persistent chesty cough with phlegm
Frequeny chest infections
Wheezing
Fatigue
Swelling in ankle, fee, or legs (adema)
205
Notes on breathing mechanics in CF (3)
Airway obstruction
Reduced pulmonary function
Impaired gas exchange
206
