Clinical Phenotypes of airway disease

Question 1

what is the difference between asthma and COPD?

Answer 1

asthma Is a reversible condition whereas COPD is irreversible

Question 2

what indicators would point to asthma over COPD?

Answer 2

-large (>400ml) response to bronchodilators
-large (>400ml) response to 30mg oral prednisolone daily for 2 weeks
-serial peak Flow measurements showing 20% or greater diurnal or day-to-day variability
-clinically significant COPD is not present if the FEV1 and FEV1/FVC ratio return to normal with drug therapy

Question 3

what are some clinical diagnosis symptoms of asthma?

Answer 3

->2 of cough, wheeze, SOB, chest tightness
-nocturnal/ AM symptoms
-triggers/ exercise/ aspirin/ b-blockers
-allergy
-family history

Question 4

what is she objective evidence for diagnosis of asthma?

Answer 4

-eosinophils/ igE/ skin prick testing/ FeNO
-PEFR variability - assuming technique okay
-spirometry - air flow obstruction/ reversibility/ variability
-bronchial challenge - airway hyper responsiveness
-imaging - normal/hyperinflated CXR or air way trapping on HRCT

Question 5

what does FeNO test tell us?

Answer 5

measures how much nitric oxide in a breath which is directly correlated with eosinophils which are mainly present in asthma

Question 6

how do measure airway obstruction or inflammation?

Answer 6

measure nitrous oxide in broth

Question 7

what are some factors on measuring FeNO?

Answer 7

-easy to do at clinic
-asnwer in <5 mins
-normal <25ppb
-abnormal >50ppb
-grey area in between
-only validated in non-smokers
-indicates eosinophilic inflammation in the airway

Question 8

how do we treat bronchoconstriction in asthma?

Answer 8

-bronchodilators (add LAMA to LABA/steroid inhalers)
-SC bricanyl for true brittle asthma

Question 9

how do we treat airway inflammation (elevated FeNO) in asthma?

Answer 9

increase/change inhaled steroid

Question 10

how do we treat allergic drive in asthma?

Answer 10

antihistamines regularly and avoidance of allergen

Question 11

how do we treat other pathways in asthma?

Answer 11

leukotriene antagonists (children/exercise/polyps)
theophyllines (mixed effacer, little objective evidence for COPD type
macrolides - no evidence

Question 12

how do we treat IgE total in asthma?

Answer 12

omalizumab monoclonal antibody

Question 13

what is chronic obstructive pulmonary disease?

Answer 13

-smoking related lung disease
-presents in middle age
-20 pack years
-10% of UK population have FEV1 below predicted value
-6% of UK adult population have symptomatic of this
-worldwide prevalence lower

Question 14

what is the pathogenesis of COPD?

Answer 14

smoking
air pollution
wood burning
occupation
nutrition
socioeconomic status
bacterial colonisation
genetics
birth and development

Question 15

where does FEV1 peak usually?

Answer 15

around 25 years

Question 16

why does smoking cause COPD?

Answer 16

hydrogen peroxide and tars turn to free radicals which results in oxidative stress and inflammation (inflammation causes further damage and lung tissue destruction)

Question 17

what is the process behind emphysema?

Answer 17

-protease antiprotease imbalance
-inflammatory cells produce an excess of protease enzymes such as neutrophil elastase (NE) over antiproteases such as a1Antitrypsin (a1-AT)
-this protease/antiprotease imbalance results in lung tissue damage and subsequent development of COPD

Question 18

what happens during emphysema?

Answer 18

airflow obstruction -> peripheral airway disease
hyperinflation
airway compression
loss of elastic support
maldistribution of ventilation (air gets into the lungs but gets trapped so oxygen does not get into blood stream)
effects gas exchange

Question 19

what Is a1-antitrypsin?

Answer 19

main anti protein in the lung

Question 20

what is the correlation between a1-antitrypsin?

Answer 20

-strongest evidence of a genetic relationship in COPD
-deficient release of this molecule results in early development of COPD
-ZZ homozygotes produce very low levels of a1-antitrpysin
-OR >30 of developing COPD
-milder forms increased incidence of COPD
-a1At implicated in <1% of patients with COPD

Question 21

who should get LTOT (long term oxygen therapy)?

Answer 21

-patients whose disease is stable on a full medical regimen with PaO2<7.3 (55mmHg) (corresponding to an SaO2 ,88%)
-patients whose Pa,O2 is 7.3-7.8kPa (55-59mmHg) (Sa,O2 89%) with pulmonary hypertension
-patients who desaturate only during exercise or sleep consider oxygen therapy specifically under those conditions

Question 22

what is type 2 respiratory failure?

Answer 22

occurs when the respiratory system cannot sufficiently remove carbon dioxide from the body, leading to hypercapnia

Question 23

what is hypercapnia?

Answer 23

high levels of CO2 in blood

Question 24

what is non invasive ventilation?

Answer 24

tight fitting mask onto face which is connected to a ventilation machine
uses bi level ventilation

Question 25

how does bi level ventilation work?

Answer 25

when patients breathe in, it triggers a big push of air into the lungs and when they breath out it leaves a small amount of pressure within the lungs to stop the airways collapsing down

Question 26

what are the potential factors that COPD would present with recurrent exacerbations?

Answer 26

-element of asthma
-bacterial colonisation
-aspergillus sensitisation
-hypoxia
-reflux
-underlying bronchiectasis

Question 27

what should not be heard on auscultations during COPD or asthma?

Answer 27

bilateral crackles

Question 28

what is bronchiectasis?

Answer 28

a long-term condition where the airways of the lungs become widened, leading to a build-up of excess mucus that can make the lungs more vulnerable to infection

Question 28

what are some presentations of bronchiectasis?

Answer 28

purulent daily sputum
50% IDIOPATHIC
RECURRENT INFECTION
CRACKLES ON EXAM

Question 29

what are some presentations of empysema?

Answer 29

breathlessness
low BMI
oxygen requirement

Question 30

what are some clinical presentations of chronic bronchitis?

Answer 30

-seasonal
-daily sputum, esp winter
-recurrent infections