Respiratory Flashcards
Give x2 consequences of COPD.
Increased goblet cell production and mucus secretion Depletion of ciliated cells. Cilia beat asynchronously.
In a healthy individual, goblet cells make up approximately what percentage of the lung?
20%
Why does fibrosis occur?
As an attempt to repair tissue
What are club cells
Non-ciliated secretory bronchiolar epithelial cells which contain detoxifying enzymes.
What is the purpose of epithelial type II cells?
Contain lamellar bodies which store and release surfactant to prevent alveolar collapse.
Which are more predominant - Type I or II epithelial cells?
Type I cells.
What is an impairment seen in alveolar fibrosis relating to Type II cells?
Type II epithelial cells cannot differentiate into type I cells. Proliferation of fibroblasts. Connective tissue synthesis
Which are the 3 secretory epithelial cells and what are their functions?
Type II epithelial cells, Goblet cells and club cells. Secrete surfactant and mucus, synthesise antioxidants, release lysozymes, secrete anti-proteases, contain cytochrome p450 enzymes.
Name an antioxidant
Glutathione
What is the main immune cell in respiratory units?
Macrophages
When are more neutrophils seen in compared with macropages?
In COPD
What do phase I and II enzymes do?
Involved with detoxification and xenobiotic metabolism - metabolise foreign bodies
What is the main way in which CO2 is transported within the blood?
In bicarbonate solution.
Respiratory disease kills how many people in the UK?
1 in 5
What is the normal value for PaO2?
> 10kPa
How do you calculate predicted maximum heart rate?
220 - age
Which is the primary inflammatory cell of asthma?
The eosinophil.
Which is the primary inflammatory cell of COPD?
The neutrophil.
Why will bronchodilators and corticosteroids not commonly be used in COPD patients?
COPD patients do not have much bronchoconstriction so bronchodilators will not have much effect. The inflammatory nature of COPD makes patients resistant to corticosteroids.
What are the two main groups of medication used in asthma?
Bronchodilators and corticosteroids.
Which inflammatory mediators are seen in Asthma Vs. COPD?
Asthma = IL-4, IL-5 COPD = TNF-a, IL-8
What is the main difference between Asthma and COPD?
Asthma is reversible whereas COPD is not.
Name x3 pathological differences seen in COPD.
- Mucus hypersecretion
- Disrupted alveolar attachments
- Bronchiolitis
Which interleukin is seen in COPD?
IL-8
What is TIMP?
Protease inhibitor
Why would a protease inhibitor help treat COPD?
Proteases contribute to alveolar wall destruction, mucus hypersecretion and mucus inflammation.
Which are the three proteases associated with COPD?
- Matrix metalloproteinase
- Serine proteases
- Cysteine proteases
Which statement is true regarding tidal volume (VT)?
It is the volume breathed during forced breathing.
It is the volume breathed in each breath.
It is the volume breathed in each minute.
It is unaffected by the frequency of breathing.
It is the volume breathed in each breath.
Which statement is true regarding expiratory reserve volume (ERV)?
ERV is kept at a low volume so that the vast bulk of the alveolar gas can be replaced with fresh air during the next inspiration.
ERV is the maximal amount of air that can be exhaled from the lungs after a normal expiration.
ERV is very small and unimportant in normal respiration.
ERV is the maximal amount of air that can be exhaled from the lungs after a normal expiration.
What is the approximate value for the ERV?
1200ml.
Which statement is true regarding residual volume (RV)?
RV is mostly found in the anatomical dead space.
RV is the volume of gas left in the respiratory system after exhaling maximally.
RV usually decreases in individuals with chronic obstructive lung disease (COPD).
RV is the volume of gas left in the respiratory system after exhaling maximally.
Which statement is true regarding vital capacity (VC)?
VC is a measure of the amount of gas that it is vital to retain in the respiratory system at the end of expiration.
VC is a measure of the maximum volume of gas in the respiratory system that can be exchanged with each breath.
VC is a measure of the volume of gas normally exchanged with each breath.
VC is a measure of the maximum volume of gas in the respiratory system that can be exchanged with each breath.
Which statement is true regarding total lung capacity (TLC)?
It increases as the frequency of breathing increases.
It is a measure of the volume of gas in the respiratory system at the end of a maximal inspiration.
It is constant in amount from person to person.
It is a measure of the volume of gas in the respiratory system at the end of a maximal inspiration.
How do you calculate TLC?
Adding together VT, ERV, IRV and RV.
In the respiratory system, what is the major difference between a volume and a capacity?
A capacity is the sum of at least two volumes.
A volume is the sum of at least two capacities.
Their units are different.
A capacity is the sum of at least two volumes.
Which statement is true regarding forced expired volume in one second (FEV1)?
It has the units of L/min.
It is the same whatever the starting volume in the airways.
It provides a measure of the resistance of the airways to flow.
It provides a measure of the resistance of the airways to flow.
Why is the volume of exhaled air more than that of inhaled air?
The gas is inhaled at room temperature which is below body temperature. As inspired air is heated within the body, a larger volume is occupied resulting in a larger volume of exhaled gas.
What does a peak flow meter allow you to assess?
A person’s VC.
A person’s VT.
The maximum rate of flow that a person can achieve during a forced expiration.
The maximum rate of flow that a person can achieve during a forced expiration.
In COPD, what does lung tissue damage result in?
Decreased RV
Decreased TLC
Decreased % FEV1/FVC
Decreased % FEV1/FVC
Name x5 aspects of treatment for cystic fibrosis
Antibiotics, hypertonic saline, oxygen, lung transplant, airway clearance, high calorie diet
What is the commonest cause of hyperaemia in lung disease?
V/Q mismatch.
COPD commonly causes….
RVH
Which region of the lung has the best ventilation to perfusion ratio?
MIDDLE (ratio!)
Which region of the lung has the best ventilation to perfusion ratio?
MIDDLE (ratio!)
Which region of the lung has the best ventilation and perfusion?
Base
What is the respiratory exchange ratio (RER)?
CO2 Production/O2 consumption.
Give x5 main characteristics of Asthma
- Chronic lung disease
- Hypersensitive bronchi (cold air, pollen)
- Excess production of mucus
- Narrowed airways
- Low FEV1/FVC
What is the normal FEV1/FVC?
> 70%
What is the main difference between COPD and Asthma?
Asthma is reversible through use of bronchodilators and corticosteroids. COPD is irreversible.
Name x2 forms of COPD
Emphysema and chronic bronchitis.
Give x5 main characteristics of COPD
- Alveolar walls breakdown
- Loss of elastin
- Excess production of mucus
- Airspaces form ‘bullae’
- Loss of elastic recoil (required for expiration)
- Hyperinflation of lungs = flattens diaphragm = less effective
- High PCO2, low PO2.
- High RV, TLC.
- FEV1/FVC <70%
Barrel chest is an indicator of what?
Someone living in high altitudes, COPD.
What you must do before performing spirometry?
Calibrate the spirometer and set it to zero.
What does peak flow measure?
Airway resistance
Name the x3 dynamic respiratory measures
FVC, FEV1, FEV
Residual volume, tidal volume and inspiratory reserve volume are all examples of what kind of respiratory measures?
Static volumes
What is the name of the volume of air inhaled and exhaled during quiet breathing?
Tidal volume
What is the name of all of the air that it is possible for the lungs to contain?
Total lung capacity
What is the name for the volume of air remaining in the lungs after a full expiration?
Residual volume
What is the name for the maximum volume that we can inhale into our lungs?
Inspiratory reserve volume
What is LaPlace’s law?
P = 2T/r
What is Poiseuille’s law?
8nl/Pier^4
How are compliance and resistance affected by COPD?
Both increase; higher volumes increases compliance. more mucus and constriction increases resistance.
What is the reason for an UNDER READING of FVC in COPD?
Poor technique.
Resistance to airflow constantly increases as the airways get narrower. True or false?
False; resistance will peak up until a certain point and then enormously decrease.
Define minute ventilation
The volume of air expired per minute.
Define alveolar ventilation
The volume of air reaching the respiratory zone per minute.
Define anatomical dead space
The capacity of the airways incapable of undertaking gas exchange.
Define alveolar dead space
The capacity of the airways that should be able to undergo gas exchange but cannot.
Define physiological dead space
Alveolar dead space + anatomical dead space.
Define hyperpnoea
Increased depth of breathing.
Define orthopnoea
Difficulty in breathing whilst lying down.
The non perfused parenchyma is another name for what?
Alveolar dead space.
Name 2 procedures which increase dead space
Smoking, snorkelling
Name 2 procedures which decrease dead space
Trachestomy, Cricothyrocotomy.
Serous cells secrete what kind of substance?
Antibacterials: lysozymes.
Name x3 functions of airway smooth muscle
Structure, secretion and tone.
How much of cardiac output is directed towards the tracheo-bronchial circulation?
2-5%.
What is the difference in blood return between the tracheal and bronchial circulation
Tracheal circulation: blood return via systemic veins
Bronchial circulation: blood return to both sides of the heart through bronchial and pulmonary veins.
Give x3 functions of the tracheo-bronchial tree
- Good gas exchange
- Warming of inspired air
- Clears inflammatory mediators
Name x5 inflammatory mediators of the airways
Histamine, arachidonic acid metabolites, cytokines, chemokines, reactive gas species.
Give x3 changes in goblet cells in smokers compared with normal individuals
Goblet cell number increases (at least doubles)
Goblet cells produce more mucus
Secretions become more viscoelastic
Goblet cells make up how many of the normal epithelial cells?
20%
Ciliated cells make up how many of the normal epithelial cells?
60-80%
How do cilia beat normally?
Metasynchronously
How do cilia beat abnormally?
asynchronously
Describe ciliated cell changes in bronchitis
Ciliated cells severely deplete
Cilia beat asynchronously
Cilia found in bronchioles
Cilia unable to transport thickened mucus = reduced mucociliary clearance
What is considered a small bronchiolar airway?
<2mm
Is COPD a small or large airways disease?
Small airways disease
Define the term Club cell
Non-ciliated secretory bronchiolar epithelial cell
Are bronchiolar ciliated cells increased or decreased in COPD?
Increased; to move mucus up to epiglottis and clear trapped debris.
Are there more or less club cells in smokers?
Less.
What is the typical pneumocyte ratio
Type I:II = 1:2 (more type II).
Which cells contain lamellar bodies and secrete surfactant?
Type II Pneumocytes.
Where is surfactant synthesised AND released?
Type II Pneumocytes
Which type epithelial cells cover 95% of the alveolar surface?
Type I epithelial cells.
What is the main function of type I epithelial cells?
Strong gas exchange; very thin
Name one other key function of type II epithelial cells apart from secreting surfactant?
Repair
Name x3 things you will see in alveolar fibrosis
Increased collagen
Increased fibroblasts
Increased type II epithelial cells; repair
Which cell is a result of abnormal repair in alveolar fibrosis?
Fibroblasts
Name three secretory epithelial cells
Goblet cells
Club cells
Type II epithelial cells
Give x5 functions of secretory epithelial cells
- Synthesise and release antioxidants
- Synthesise and secrete antiproteases
- Release lysosymes
- Secrete protective lining layer
- Contain cytochrome P450, phase I and II enzymes
What is glutathione an example of?
An antioxidant
What is xenobiotic metabolism?
Increasing the polarity of xenobiotics (drugs) so they are easier to excrete.
Are the respiratory units made up of mainly neutrophils or macrophages?
Macrophages.
Are the airways made up of mainly neutrophils or macrophages?
Macrophages in non-smokers (70:30)
Neutrophils in COPD (30:70 m-n)
Metalloproteinases inactivate what?
Alpha 1 antitrypsin
What is alpha 1 antitrypsin?
A serine protease inhibitor. It protects the lungs from inflammation.
What are phase I and II enzymes particularly involved in?
Xenobiotic metabolism.
Name an example of a non-small cell lung cancer
Adenocarcinoma (large)
Brain and liver metastases are what stage metastases?
M1b.
Which cancer type could be established for 13 years before diagnosis?
Adenocarcinoma
Are squamous carcinomas small-cell or non small cell?
Non-small cell carcinomas (large).
Define allergy
An exaggerated immune response to a foreign substance. A mechanism - not a disease.
Define atopy
The hereditary predisposition to produce IgE antibodies .
Asthma affects what proportion of the population?
8-12%
If a disease is described as being heterogenous it has many……
different phenotypes.
Name two things which asthma is determined by
Severity and cause (?allergic, ?exercise-induced)
Name one anti-inflammatory interleukin
IL-35
Name two differences between bronchitis and pneumonia
Bronchitis = Inflammation in the airways, tracheal chest pain Pneumonia = Inflammation in the lung interstitium, pleuritic chest pain
Give 3 guidelines for diagnosing pneumonia
- Acute lower respiratory tract symptoms
- New x-ray changes
- x1 systemic feature (fever, shiver, ache)
What is the formula for alveolar partial pressure?
PAO2/ CO2
What is fick’s law?
CO = O2 consumption/ A-V O2 content
What is VO2?
Oxygen consumption
What does the Borg scale measure?
Intensity of sensation
