Respiratory Flashcards
Name two things that lower lung compliance
Oedema and fibrosis
What are the name of three conditions causing diaphragmatic muscle weakness ?
Muscular dystrophy, spinal muscle atrophy and myasthenia gravis
What is the volume of dead space
2cc/kg
Poiseuilles law
Flow = pressure x r4 x pi / 8 x viscosity x length
Significant response in spiro to bronchodilator
12% increase fev1
Ficks law
Flux is directly proportional to the steepness if the gradient (pressure difference both sides and area by which diffusion occurs) over thickness
Two main causes of VQ mismatch and examples
- Shunt (cardio or pulm I.e AV malformation)
2. Dead space increased I.e in PE, mucous plug
A-a gradient
Alveolar gas equation
Body plethysmography utilises Boyles law
In a closed system pressure and volume change inversely when temperature is constant
What is Niemann-Pick disease?
Types A,B,C1andC2 lysosomal storage disorder
Most common virus causing croup
Parainfluenza Type 1
How many mm at 2nd cervical vertebrae would be concerning for retropharyngeal abscess
7mm
What does a displaced uvula in a teenager possibly represent?
Peritonsillar abscess
What percentage of kids with tracheolaryngomalacia have cardiovasc abnormalities
60%
Name four other odd causes of bronchi tasks
UC, Alpha antitripsan def, young syndrome, sawyer-James-Macleod syndrome
Inheritance of primary ciliary dyskinesia
AD
Vocal cord dysfunction spirometry change
Flattening of the inspiratory flow loop
How does montelukast work
Block effects of cysLT1 receptor (leukotriene receptor antagonists)
Cf newborn screen
Blood immunoreactive trypsinogen
Falsely elevated saturation from
Methaemoglobimaemia
Sickle cell and sats
Can be high or low
Macrolide use in CF for
Anti inflammatory effect
Narcolepsy test
Multiple sleep latency test
Kartageners syndrome is
Primary ciliary dyskinesia
AR
Dextrocardia
Bradycardia with cabal stimulation treat
Atropine
Three most common mutations CF
F508
G451X
G551D
5, 12, 31
Pulmozyme
RhDNase
Synthetic enzyme reduces sputum viscosity
For FeV1 persistently below 70%
K complexes and spindles in which stage of sleep
N2 (3)
% with OSA and sleep disordered breathing
OSA 1-4%
SDB 12-13%
Nasal steroids OSA
Halve score can cure mild
High CO2 indicates
Inadequate ventilation
Does dry air worsen asthma
Yes
Provocation asthma timing after intense exercise
6-8min (HR 85% of max)
Montelukast timing of action
2 hours and accelerates recovery
LABa not recommended isolated use in children because
Reduction in B2 density
Cytokines produced by Th2 in asthma
IL-4/5/13
Older child montelukast (blocks leukotreine receptors)
EIA if on ICS and no improvement with LABA
Over 12 with severe asthma can use
Omalizumab (humanised monoclonal anti-IgE antibody) sc
Wheeze persisting from viruses (name 2)
RSV
Rhinovirus
CF screened for using
Immunor active trypsinogen level and genetics
Azithromycin in CF
Anti inflammatory
Ivacaftor used for
CF G551D mutation to improve transport of Cl through ion channel
Cataplexy is
Intense emotions cause sudd n loss of muscle tone
Periodic sleepiness syndrome
Klein-levin syndrome
Multiple sleep latency test in narcolepsy
Short latency (quick to sleep) and two periods of REM
Narcolepsy two special tests and results
HLA 95% positive for DQB1*0602
(Also positive in 20% normal)
Hypocretin-1 levels low or absent in CSF
What Does sleep deprivation lead to
Obesity (more time to eat and more hungry)
Leads to inflam and insulin resistance
Slow sleep waves in
N3
R.E.M. With age
Decreases
Adolescent sleep duration in time
Has decreased
Percent of autism with sleep problem
44-83%
Parasomnia vs frontal lobe sz
In frontal lobe sz not related to stage of sleep, pointing and pelvic thrust stereotypical and looks same each time
Treat Periodic limb disorder with
Iron
Commonest cause of hypersomnia (excessive sleepiness)
Lack of sleep
Variation limit in spirometry performance
5%
Flow loop in obstruction
Concave
Spirometry flattened inspired curve causes
Vocal cord paralysis or dysfunction
Flat expiration curve spirometry cause
Tracheomalacia (variable intrathoracic obstruction)
Flat inspiration and expiration curve cause
Tracheal stenosis (fixed upper airway obstruction)
Loss of loop contour on spirometry due to
Poor effort
Jaggered expiration on spirometry
Coughing
Airway resistance highest..
Nasal airway (50% total) Intermediate bronchi (4-8th generation)
Inspiration and expiration muscles (NMD)
Insp (diaphragm)
Exp (intercostal and abdominal
)
Aspirin overdose ABG
Respiratory alkalosis
Age can use dry powder inhaler
6
Montelukast
CysLT1 receptor on bronchial sm antagonist (leukotriene 4 blocked)
DMD thresholds in FVC
<60% is SDB
<20% daytime respiratory failure
CF FEV1 0% survival perfect in 2 years
50%
Lung transplant
Most useful spirometry measurement in obstructive lung disease progression
FEV1
NMD respiratory test to detect early failure
Polysomnography
FEV1 severity
> 70% mild
50% moderate
35% severe
I NO short duration of action due to
Binding to hb
iNO near tracheal tube due to
Minimise risk of NO2 which is toxic
Virus associated with brochiolitis obliterans
Adenovirus
L atrial enlargement compresses what
L main bronchus
Most common pathogen in CF
SA
Max fluticasone under 12y
Usually 200mcg but can go up to 400mcg if >4y
90% of effectiveness achieve at dose of 125mcg/day or 250mcg/day budesonide
PaO2 at 70%, 80%, 90%
40’ 50, 60
More sensitive in small airway disease
Recent research suggests that FEF25-75% or FEF25-50% may be a more sensitive
parameter than FEV1 in the detection of obstructive small airway disease
current practice guidelines
recommend using FEV1, FVC, and FEV1/FVC as indicators of obstructive disease.
Low FEV1 indicates current obstruction (impairment) and risk for future exacerbations
(risk). For children, the ratio of the FEVI/forced vital capacity (FVC) appears to be a
more sensitive measure of severity and control in the impairment domain. FEV1 is a
useful measure of risk for exacerbations,
serum periostin
a protein secreted by airway epithelial cells and lung fibroblasts in response to IL-4 and IL-13
What to us in asthma if all avenues exhausted
Omalizumab is a humanized, monoclonal anti‐IgE
antibody that binds specifically to circulating IgE
molecules, thus interrupting the allergic cascade.
Consider > 12 years for severe allergic asthma when all
other avenues exhausted.
Given by a subcut injection – may get site reactions
Well tolerated, but occasional anaphylaxis (medical
supervion needed)
Costly. NZ$500
Which viruses are associated with
increased risk of wheezing
persisting at age 6 years?
Think of 2 viruses
RSV
rhinovirus
Most common CF genetic mutations (3)
delta F 508, G451X and G551D
Sweat test not reliable when
<75g sweat (false if <60 Cl)
- Malnutrition
- Mineralocorticoid use
3.Adrenal insufficiency
4.Fucosidosis - G6PD deficiency
Azithromycin action in CF
Anti inflammatory
ivacaftor use for
Class III mutations in CF gene
Scimitar syndrome, or pulmonary venolobar syndrome , is…
a rare congenital heart defect characterized by anomalous venous return from the right lung
Surfactant def accounts for 10% ILD what are the four genetic def
Protein B (SPB)
Protein C
ABCA3
Thyroid transcription factor related disease
Ventilator tidal volume in relatively normal lungs
7-10ml\kg
Ground glass on CT indicates
Neuroendocrine cell hyperplasia of infancy
Long history of SOB on exertion and bay wing appearance on CXR with bronchopulmonary lovage milky coloured
Pulmonary alveolar proteinosis (increased surfactant)
Oxygen index equation
Oxygen index = (FiO2 x MAP)/PaO2
Is flow curve doesn’t meet the
Poor technique
Main component of surfactant
Phosphatidycholine
What virus can cause obliterative bronchiolitis
Adenovirus can cause obliterative bronchiolitis.
Round pneumonia under 8y most commonly due to
Strep pneumoniae
Proposed underdevelopment of pores of kohn and canals of lambert
Xray for suspected inhaled FB
Insp and exp films (air trapping)
Incidence CF
1/3,500
Types of CF mutations
5 main classes:
I: Lack of/no protein production.
Eg: Stop codons (eg. Trp1282X, Gly542X) and splicing defects
with no protein production.
II: CFTR not processed correctly, so no protein gets to the cell
membrane.
Eg: Phe508del.
III: Defective regulation; but transfer of CFTR occurs.
IV: Reduced chloride transport/current through CFTR at the apical
membrane.
V: Synthesis of CFTR abnormal but is transferred.
DMD study to review early respiratory failure
Polysomnography (sleep study)
Fractional exhaled NO associated with eosinophilic airway inflammation therefore high value predicts ? And low value what two conditions
High - atopy (asthma)
Low - CF/ciliary dyskinesia
Peak of bronchoconstriction how many minutes after start exercise
10
Long acting beta agonist not safe alone because
Reduction of beta two density
Virus associated with increased risk of wheeze persisting at 6y
Rhinovirus
RSV but gone by 11y
Ivacaftor for class?
Three
Another test for restrictive and asthma
Plethysmography
Exercise test
Best lung test in restrictive?
FVC
Inert gas washout actually can measure
Rv and FRC
Two test to review FRC
Plethysmography
Inert had washout test
Gas transfer test?
Diffusing capacity of lung to carbon monoxide
