Respiratory Flashcards
At what vertebral level does the trachea begin?
C6
What is a typical tidal volume?
500 ml
What is a typical residual volume?
1200ml
If the lung is full of fluid, how will vocal resonance sound?
Louder
What is the majority of acute epiglottitis caused by?
Haemohpilus influenzae Type B
What do we call pus in the pleural space?
Empyema
HIgh pH and normal PaCO2 = what?
Metabolic alkalosis
Give a 2 word definition of asthma
Reversible bronchoconstriction
There is chemotaxis of which cell type in the delayed phase of asthma?
Mast cells
Lymphocytes
Eosinophils
Macrophages
Basophils
What is a Ghon’s complex comprised of?
Gohn focus + lymphadenopathy
Which lobe does secondary TB typically affect?
Upper lobe
What is Potts disease?
Single organ TB of the spine
What level must PaO2 drop below before it has an effect on ventilation?
~50mmHg
What information about cough must be obtained during history taking?
Site: throat vs deep chest
Quality: Dry vs wet; colour; thickness; pus; blood
Severity: volume of sputum (teaspoon vs cup)
Time course: duration
Context: Exertion; time of dayl time of year; smoking
Aggravating:
Relieving: medications
Associated features: pain while coughing
Vaccination Hx
Smoking Hx
What is haematemesis?
Vomited up blood
In which species is Type A influenza virus found?
Humans and other species
Which muscles may be contracted for forceful exhalation
Abdominal and internal intercostal muscles
Where does rotavirus replicate?
Rotavirus replicates in epithelial muscosa of GIT
What are the most common causes of otitis media?
Pneumococci,
H. influenzae
Moraxella catarrhalis
Hiow much oxygen is consumed at rest?
250ml/min
Define breathlessness
Pt’s recognition of an inappropriate relationship between respiratory work and total body work
What is corryza?
Runny nose
Name 4 features of airway remodelling in asthma that cause obstruction of the airways
Goblet cell hyperplasia with increased mucous production
Subepithelial collagen thickening
Increased airway smooth muscle volume
Increased mucosal vascularity
Define Gohn focus
Gohn focus = peripheral area of granulomatous inflammation and caseation
Which 3 factors determine fluid movement across pulmonary capillaries?
1 Hydrostatic pressure
2 Oncotic pressure
3 Capillary permeability
Define phlegm
Mucous + cell debris/bacteria/DNA etc
That is in the body
What is a medical way of saying “coughing up blood”
Haemoptysis
What is the most common cause of the common cold?
Rhinovirus
What influences the peripheral chemoreceptors involved in respiratory regulation?
PaO2, PaCO2, pH
What is the double fold of pleura inferior to the hilum called?
Pulmonary ligament
What is a normal PaCO2?
38-42 mmHg
On a CXR, what causes Kerley b lines?
Dilated lymphatics
What are 3 complications of emphysema?
1 hypoxia
2 pulmonary hypertension –> cor pulmonale
3 PTx
Define mucous
Physiological substance that is in the body
HIgh pH and low PaCO2 = what?
Respiratory alkalosis
What is on your list of differentials for haemoptysis?
Bronchitis
Pneumonia
Bronchiectasis
Pulmonary embolis
Tuberculosis
Lung cancer
Trauma
Inhaled foreign bodies tend to travel where?
Right main bronchus to right lung
What is a normal PaO2?
90-98 mmHg
What is the most viral common causes of croup?
Parainfluenza
What is the pressure of O2 at sea level?
160 mmHg
How does cigarette smoking lead to emphysema?
Cigarette smoke -> ROS -> alveolar damage
Smoke -> ROS –> neutrophil recruitment –> elastase -> alveolar septal degradation
Smoke -> inactivation of anti-proteases -> increased elastase -> alveolar septal degradation
What do people with chronic hypercapnoea have an increased dependence on for ventilatory regulation?
Respiratory drive
What does work of breathing include?
Elastic and resistive work
Which cell makes up most of the surface area of the alveolus?
Type 1 pneumocyte
What is stridor?
An audible breathing sound from the throat (often on inspiration)
What are the 4 most common viral causes of pneumonia?
Parainfluenza 3
Respiratory syncytial virus
Influenza virus
Adenovirus
What is a normal mixed venous PO2?
40mmHg
What causes excess mucus in chronic bronchitis?
Hypertrophy of mucus secreting glands
Increased goblet cells
What are the side effects of inhaled GCSs?
Oral candidiasis
Dysphonia
Decreased serum cortisol
What clinical feature particularly distinguishes influenza from other respiratory tract infections?
Muscle aches
What are 3 important DDx for peripheral oedema?
1 Left heart failure
2 Low serum protein
3 Fluid volume overload
What does Fick’s law determine?
Rate of diffusion of a gas
What are 2 unique features of the Mycobacterium tuberculosis cell wall?
Contains mucolic acid in the cell wall, giving it a waxy coating.
It is acid fast
What is a normal pulmonary artery sys/dias blood pressure?
25/8 mmHg
What is the role of neuraminidase in influenza infection?
NA (neuraminidase) cleaves the sialic acid off the epithelial receptor to prevent newly released virus particles from re-infecting that very cell
What are 2 conditions that can cause hypoventilation through neuropathy?
Polio virus
Guillain-Barre syndrome
What is the range of normal respiration rates for an adult person at rest?
12 to 16 breaths per minute
What is a normal mixed venous CO2?
46 mmHg
Where are peripheral chemoreceptors that contribute to respiratory regulation?
Carotid bodies and aortic arch
What percentage of acute sore throats are caused by viruses?
70%
What is a typical total lung capacity?
5.7L
Where are pulmonary veins always situated within the hilum?
Anterior and inferior
If the radius of a small airway is halved, by how much will resistance increase?
16 times
Define emphysema
Permanent and abnormal enlargement of the airways distal to the terminal bronchioles
What is the order of pharmacological agents used to treat COPD as disease severity increases?
1 Short acting bronchodilator if FEV1 >80?
2 Long acting bronchodilator if FEV1 = 50-80?
3 Inhaled GCS if FEV1 = 30-50%
4 Oxygen if FEV1
What are the most common bacterial causes of atypical pneumonia?
mycoplasma pneumonia,
Coxiella Burnetti,
Chlamydophila pneumoniae
Legionella spp
What is the normal range for arterial pH?
7.35 - 7.45
Alveolar pneumonia is characterised by what?
Consolidation (neutrophils) in the alveolar spaces
What is the best imaging modality for the lung parenchyma?
CT
Yellow sputum suggests what are present in the sputum?
Neutrophils
What does a CXR classically show in atypical pneumonia?
Reticulonodular infiltrate: “dots and dashes” throughout both lung fields
What are the most common causes of a flu-like sickness?
Influencza
Respiratory syncytial virus
In which species is Type B influenza virus found?
Humans only
How does consolidation of pneumonia appear on CXR?
Hyperdense = white
What is the most common viral cause of pharyngitis?
Adenovirus
What is the major cause of empyema?
Staph. aureus
What’s the most common bacterial cause of a sore throat?
Streptococcus pyogenese
What are the most common pathogenic agents for acute exacerbation of chronic bronchitis?
Haemophilius influenzae Streptococcus pneumoniae
Koplick spots are diagnostic of what disease?
Measles
What is a medical way of saying “vomited up blood”?
Haematemesis
List 6 clinical features of atypical pneumonia
Malaise,
aches/pains,
HA,
diarrhoea
Dry non-productive cough
Patients often ambulant (walking pneumonia)
What is the fancy way of saying “coughing up blood”?
Haemoptysis
An unconscious supine patient who vomits will most likely have fluid in which lung segment?
Apical segment of the lower lobe of the right lung
What is a normal PAO2?
100mmHg
What type of respiratory disorder does pneumonia cause?
Restrictive
What do we know about the receptor for influenza virus?
Terminal sialic acid bonded via alpha 2-6 linkage to galactose
Name 4 features of congenital rubella syndrome
Microcephaly
Deafness
Cataracts
Congenital heart defects
What type of cartilage is in the trachea?
Hyaline
In what pattern of distribution is consolidation in bronchopneumonia?
Multifocal and patchy
What kind of flow occurs in large airways?
Turbulent
What is the definition of chronic bronchitis
Persistant cough, productive of sputum for at least 3 months in at least 2 consecutive years
Not due to another cause
What does a wheeze imply?
Pathology in the airways
What is a saddle pulmonary thrombo-embolism?
One that spans across the pulmonary trunk
What is implied by crackles on ausculation of the lungs?
Fluid in alveoli or terminal bronchioles.
Could be pus, haemorrhage, oedema, salt water
What is the most common pattern of bacterial pneumonia?
Bronchopneumonia
What changes are there in ABG in Type 2 respiratory failure?
Low PaO2 and high PaCO2
What are 3 pathological features of the immediate response in asthma?
Oedema,
mucous production and
bronchospasm
What is the O2 saturation of venous blood?
75%
What are the most common pathogenic agents that cause an acute exacerbation of chronic bronchitis?
Pneumococcus
H. influenzae
What is the pathophysiological definition of emphysema
Destruction of the alveolar wall without fibrosis
What is the incubation period of influenza?
1-5 days
What is empyema?
Pus in the pleura
Define asthma (in more than 2 words)
Hyper-responsive airways…
…to various stimuli…
which leads to episodic bronchoconstriction
that is at least partly reversible
What is the name of the active transporter that pumps Ca2+ into the SR in smooth muscle?
SERCA
How does emphysema cause airway obstruction?
There is a loss of elastic recoil,
leading to collapse of small airways
Pleural friction suggests what type of pneumonia?
lobar pneumonia
What is the mechanism of omalizumab in asthma treatment?
Blocks mast cell degranulation via steric hindrance of Fc portion of Ab, blocking IgE binding to mast cell
Low pH and low PaCO2 = what?
Metabolic acidosis
What is a typical minute ventialtion?
7-8 L/min
What is haemoptysis?
The expectoration of blood or of blood-stained sputum
What is the average number of deaths annually from influenza in Australia?
1,500
What is the medical term for a sore throat?
Pharyngitis
What is the role of haemagglutinin in the influenza virus?
Binds to sialic acid containing receptor → initiates entry
The transition from bronchi to bronchioles is marked by which histological feature?
Disappearance of cartilage in the wall
When are inhaled GCSs indicated in the treatment of asthma?
When the patient requires beta 2 agonists more than three times weekly
Which pattern of pneumonia is more common in 20-50 years olds?
Lobar pneumonia
What are the 3 most common viral causes of URTI?
Rhinovirus
Corona virus
Adenovirus
What is the cut off for abnormal FEV1/FVC in a healthy young adult?
80%
What is the pathogensesis of chronic bronchitis?
Cigarettes -> inflammation:
–> mucous production in larger airways
–> scarring and narrowing of smaller airways
What must happen to the influenza virus for it to be activated once it leaves a respiratory eptithelial cell?
Must be cleaved by tryptase clara
What coloured phlegm do viruses tend to cause?
White
Give an example of a virus that causes a latent infection
Herpesvirus
What does central cyanosis imply?
Hypoxaemia (low PaO2)
What are 5 potential respiratory system causes of dyspnoea?
1 Airways
2 Alveoli
3 Pleura/chest wall
4 Pulmonary vasculature
5 Respiratory muscle
What does pruritus mean?
Itchy
What are 5 classes of causes of inadequte ventilation?
1 Central
2 Neuromuscular eg MND
3 Obesity
4 Chest wall deformities
5 Sleep disordered breathing
What are complications of chronic bronchitis
Superimposed infective exacerbations
Hypoxia
Pulmonary hypertension
Squamous metaplasia and dysplasia leading to malignancy
Where would painful irritation of the costal parietal pleura be experienced?
Thoracic wall (because parietal pleura is innervated by branches from intercostal nerves)
Where does the respiratory virus replicate in humans?
Virus replicates in respiratory epithelium, esp in large airways such as bronch
What is the first level of the airways where gas exchange may occur?
Respiratory bronchioles
What are the most common pathogenic agents for low severity index community-acquired pneumonia?
Streptococcus pneumoniae
Mycoplasma pneumoniae
Chlamydophila pneumoniae
What is the defining histopatholgoical feature of idiopathic pulmonary fibrosis
Interstitial inflammation with firbosis at varying stages of development
What is the most common preventable cause of death in hospitalised patients?
Venous thrombo-embolism
Which type of pneumonia is more common at extremes of age?
Bronchopneumonia
What is the GPCR downstream effect of salbutamol leading to bronchodilation
Increases activity of SERCA, which takes up Ca2+ into SR, decreasing ASM contractility –> bronchodilation
What is the most common cause of aortic stenosis?
Dysrtrophic calcification
How may someone with PE present?
Dyspnoea
Haemoptysis
Cough
Syncope
Pleuritic pain
Which influenza type has many subtypes?
Type A
What stimulates central chemoreceptors involved in respiratory regulation?
[H+]
What are the 4 stages of lobar pneumonia?
1 Congestion
2 Red hepatisation
3 Grey hepatisation
4 Resolution
What is the pathogenic agent in typhus?
Rickettsia
What type of respiratory disease does emphysema cause?
Obstructive
What causes antigenic drift in influenza virus?
RNA-dependent RNA polymerase errors during replication lead to single amino acid changes in HA or NA sites that reduce affinity of neutralising antibodies.
These viruses will be selected for, and a new strain will emerge
What is the defining feature of the histopathology of restrictive lung diseases?
Inflammation and fibrosis of inter-alveolar septa (interstitium)
Low pH and high PaCO2 = what?
Respiratory acidosis
What type of respiratory disease does asthma cause?
Obstructive
What percentage of people have viridans streptococci in their URT?
100%
What kind of flow occurs in small airways?
Laminar
What information about sputum must be obtained during history taking?
Colour
Volume
Thickness
Pus
Blood
What type of breathing pattern would be adopted by a person with stiff lungs?
Rapid shallow breaths
The transition from terminal bronchioles to respiratory bronchioles is marked by which histological feature?
Breaks in the continuity of the walls
What is haemoptysis?
Coughed up blood
What is the most common valvular disease in Western world?
Aortic stenosis
What are the side effects of short acting beta 2 agonits?
tachycardia,
tremor and
hypokalemia
Which lung volumes are reduced in restrictive respiratory diseases?
All lung volumes are decreased
List 4 histological featrues of interstitial pneumonia
1 Lymphocytes, macrophages and plasma cells present in the alveolar septa (ie interstitium)
2 Alveolar septa are widened
3 No inflammatory cells in the alveoli
4 Bronchiolitis
Define cor pulmonale
Right sided heart failure caused by pulmonary hypertension
What type of respiratory disease does COPD cause?
Obstructive
What is the medical way of saying runny nose?
Corryza
What type of respiratory disorder does pulmonary oedema cause?
Restrictive
What are 3 distinguishing features of the right main bronchus compared with the left main bronchus?
Shorter, wider and more vertical
What is the most numerous cell in the alveolus?
Type 2 pneumocyte
How much CO2 is produced at rest?
200ml/min
What is the most common cause of pneumonia?
Pneumococcus
How would you distinguish haemoptysis from haematemesis on history taking?
Prodome: (irriation in chest or desire to cough)
Colour: bright red = haemoptysis; dark red = haematemesis
Frothiness: frothy = haemoptysis; not frothy = haematemesis
Pain: localised to URT, chest, or epigastric
If there is a pneumothorax, how will vocal resonance sound?
Duller/softer
An abnormally low FEV1/FVC implies what type of respiratory dysfunction?
Obstructive
Is gas diffusion across the A-C membrane perfusion- or diffusion-limited
Perfusion
Define sputum
Expectorated product
At what level of the respiratory system do airways lose cartilage in their walls?
Bronchioles
What percentage of pneumonia is due to bacteria?
85%
How many people out of 100,000 in Australia have tuberculosis?
4
How is TB transmitted between people?
Infected aerosolised droplets
What is under nervous control within the lungs?
Mucous production and diameter of bronchi
What are the 3 broad causes of pulmonary HT?
Increased left atrial pressure (eg mitral stenosis)
Increased pulmonary blood flow (eg excess central volume)
Increased pulmonary vascular resistance (eg emphysema, embolism)
What are the 2 most common causes of the common cold?
Rhinovirus and coronavirus
How is Type 1 respiratory failure diagnosed?
PaO2 less than 50 mmHg, with evidence of respiratory compensation.
Where would painful irritation of the diaphragmatic pleura be experienced?
Pain in the lateral neck and supraclavicular region of the shoulder (C3-C5 dermatomes)
How could you assess whether alveolar ventilation is adequate?
PaCO2
What is miliary TB?
Mycobacterium TB that has spread through blood to infect other organs
What is a normal PACO2?
40mmHg
List 5 clinical features of pneumonia
1 Intractible cough
2 that is productive of green/yellow sputum
3 fever and chills
4 Chest pain (if pleural inflamed)
5 Impaired gas exchange –> dyspnoea and tachypnoea
Sleep deprivation of how long will result in cognitive performance equivalent to BAC of 0.05?
18-24 hours
What happens to PaCO2 during sleep?
Increases from 40 to 45mmHg
How many sleep cycles are there in a night typically?
4-6
What is a typical length of a sleep cycle?
90-120 mins
Where does the suprachiasmatic nucleus project to?
Paraventricular nucleus
Which nucleus in the brain releases histamine?
Tuberomammilary nucleus
Which nucleus in the brain is activated by adenosin and depleted ATP and inhibits ascending cholinergic and monoaminergic neurones to promote sleep?
Ventro-lateral preoptic nucleus
Do you get fibrosis in emphysema?
No
In percussion of the chest, how will different tisuues sound from dullest to most resonant
Fluid -> Solid organs -> Lung -> Air
What type of noradrinergic receptors are found in the lungs?
Beta 2 (because you have 2 lungs)
Which nerve passes in front of the lung root?
Phrenic nerve
Which nerve passes behind the lung root?
Vagus nerve