WEEK 11

Question 1

What is allergic asthma?

Answer 1

Recurrent reversible airway obstruction with attacks of wheezing, shortness of breath & often a nocturnal dry cough
- airway inflammation, bronchial hyper-resposiveness

Question 2

What is the pathogenesis of asthma?

Answer 2

activation of Th2 profile of cytokine production in genetically susceptible people

• it attracts eosinophils to mucosal surface
• IL-5 & GMCSF cause eosinophils to produce cysteinyl leukotrienes & release granule proteins
• IgE synthesis promoted & expression of IgE receptors on mast cells & eosinophils

Question 3

What are important mediators in asthma?

Answer 3

• leukotriene B4 and cysteinyl- leukotrienes IL-4, 5 and 13, and tissue damaging eosinophil proteins

Question 4

What is used to monitor the treatment of asthma?

Answer 4

Peak expiratory flow rate

- also FEV, O2 sats and arterial blood gases

Question 5

What are the 5 main classes of drugs used to treat asthma?

Answer 5

1. Beta 2 adrenoreceptor agonists
2. Anti - inflammatories
3. Cysteinyl leukotriene antagonists (LTRA)
4. Methylxanthines
5. Anti-IgE treatment

Question 6

Give examples of Beta 2 adrenoreceptor agonsts.

Answer 6

SABA e.g. salbutamol (lasts 3-5 hrs)

LABA e.g. salmeterol (lasts 8-12 hrs)

Question 7

Give examples of inflammatory mediators. What is their action ?

Answer 7

GLUCOCORTICOIDS e.g. beclometasone, budesonide

• they prevent progression of chronic asthma
• decrease: formation of cytokines, generation of vasodilators and activation of eosinophils
• in deteriorating asthma, oral (prednisolone) or IV (hydrocortisone) can be given

Question 8

Give an example of a cysteinyl leukotriene antagonist. What is its MoA?

Answer 8

Montelukast

• antagonises only CysLT1 which decreases exercise induced asthma and decreases early and late allergen responses, relaxes airways in mild asthma and decreases acute reactions to aspirin
• is used mainly as an add on to ICS and LABAs

Question 9

What are methylxanthines? What are they used for?

Answer 9

Theophylline and its derivatives

• theophylline = increases cyclic nucleotides in cell to relax smooth muscle
• uniphyllin orally in addition to steroids for COPD
• rarely it is used IV aminophylline in acute severe asthma

Question 10

Give an example of an anti-IgE treatment drug.

Answer 10

Omalizumab

Question 11

What is the steps/process for treating acute severe asthma?

Answer 11

IMMEDIATE TREATMENT (adults)
- O2 (sats kept at 94-98%)
- salbutamol or terbutaline plus ipratropium via nebuliser
- IV hydrocortisone or prednisolone tablets
IF NO IMPROVEMENT IN PT
- IV magnesium sulphate
- switch from nebulised to IV salbutamol or aminophylline
MONITOR BLOOD GASES and PT EXHAUSTION/ALERTNESS

Question 12

What is ipratropium? What is it used for?

Answer 12

SAMA used for some COPD patients, especially the long acting (LAMA) version - tiotropium

• rarely used in asthma
• used for cough caused by irritant stimuli
• decreases augmentation of mucus secretion and may increase bronchial secretion clearance
• not selective for one muscarinic type
• used for bronchospasm precipitated by beta blockers
• not effective against allergen challenge

Question 13

What does PICO stand for?

Answer 13

Patient
Intervention
Comparison
Outcome

Question 14

What is the 3 points for the ‘anatomy’ of a good question?

Answer 14

1. Define who the q is about
2. Define which option you’re considering (drug treatment) and a possible comparison (placebo or stnd therapy)
3. Define desired (or undesired) outcome

Question 15

What are the 3 types of information resources? (HINT: put in order of importance/priority)

Answer 15

1. Systematic Reviews and Meta-analyses
   - cochrane reviews, 2ndary sources of info
2. Clinical practice guidelines
   - NICE and SIGN
3. Original article containing primary research data (RCT)

Question 16

What is hypothesis construction? What is the difference between a null and alternative hypothesis?

Answer 16

Is one set of data different from another?
NULL = 2 sets of data from same population and NOT different
ALTERNATIVE = 2 sets of data from different population and are different

Question 17

What are the 2 types of quantitative data? Describe them.

Answer 17

DISCRETE - can only have certain numerical values

CONTINUOUS - don’t have discrete steps

Question 18

What are the categorical variables? Describe them.

Answer 18

NORMAL (unordered categories)
- male/female, green/blue eyes, alive/dead
ORDINAL (ordered categories)
- objective: heavy, moderate or light drinkers, grade of breast cancer
- subjective: health status questionnaires

Question 19

What is hypothesis testing? What is the P value? What does a P of 0.1 mean? What value of P means a null hypothesis can be rejected?

Answer 19

Assume null hypothesis and determine the probability that the null hypothesis is correct: P value
P of 0.1 = 10% chance null hypothesis is correct
If P<0.05 then null hypothesis can be rejected as there’s a statistically significant difference

Question 20

What is a (i) type I (ii) type II error?

Answer 20

(i) Rejecting null hypothesis when it is true (false +ve)
- concluding there’s an effect when there isn’t
(ii) NOT rejecting null when it’s false (false -ve)
- concluding there’s no effect when there is

Question 21

What is the power of a test?

Answer 21

Its ability to reject a null hypothesis when it is false

- the capacity to detect an effect if one present

Question 22

What is the pathogenesis of AMI?

Answer 22

Atherosclerotic plaque destabilisation

• rupture or erosion
• platelet adherence and aggregation
• intracoronary coagulation

Question 23

What are the 4 complications of an acute myocardial infarction?

Answer 23

1. ARRHYTHMIA
   - bradycardia = heart block
   - tachycardia = AF, VT, VF
2. MYOCARDIAL DEATH
   - pericarditis, VSD, free wall rupture, papillary muscle necrosis
3. LV THROMBUS and EMBOLISATION
4. HEART FAILURE
   - pump failure
   - LV dilatation
   - LV aneurysm

Question 24

How do you know if someone is dead?

Answer 24

1. Cessation of the CIRCULATION
   - no pulses
   - no cardiac activity (no heart sounds or electrical activity)
2. Cessation of RESPIRATION
3. Cessation of CEREBRAL function
   - fixed dilated pupils (don’t constrict in response to a light stimulus)

Question 25

What is the pathology of myocardial infarction? (HINT: there's 4 points)

Answer 25

1. Myocyte death 2. Coagulation 3. Inflammation - neutrophil recruitment - monocyte recruitment and macrophage formation - digestion and removal of debris 4. Granulation and scar formation

Question 26

Why is the association of psychological factors to asthma important?

Answer 26

``` Asthma related deaths Near fatal asthma Brittle asthma Non-compliance A&E visits ```

Question 27

What are the main psychological factors of significant importance with relation to asthma?

Answer 27

depression anxiety panic denial

Question 28

What is the prevalence of anxiety within asthma children/adolescents? What does the expression of fear allow for?

Answer 28

up to 33% meet the criteria for comorbid anxiety disorders Allows for appropriate psychological formation - provision of information, discussion of accuracy, planned intervention and treatment plan

Question 29

How do you encourage the exploration of fears?

Answer 29

attentive listening comforting guidance quiet and accepting presence

Question 30

What is breathlessness a symptom of? What is it seen/explained as?

Answer 30

Respiratory disease AND panic attacks | - seen as complex interplay between between emotional, psychological, physical and functional factors

Question 31

Describe the association of asthma and avoidance of it as a disease.

Answer 31

12-20 % pts refuse to accept asthma diagnosis - avoidance is good short term (3 days) but long term it leads to more anxiety and depression, reduces physical functioning and more discomfort

Question 32

What are the illness representations within Leventhals "Common Sense Model"?

Answer 32

1. IDENTITY: name, signs and symptoms 2. CAUSE: internal or external 3. CONSEQUENCES: physical, social, economic, emotional 4. TIMELINE: acute, recurrent, chronic 5. CURE/CONTROL

Question 33

What does the process of finding a cause for an asthma attack help patients with?

Answer 33

To make sense of their illness experience to guide their future self-management

Question 34

Why is self-management important?

Answer 34

Prevents exacerbations Improves care Is a cost effective investment for healthcare services

Question 35

What is a confidence interval?

Answer 35

It describes the uncertainty of the point estimate (mean) | - a range of values in which we can be relatively sure that the true effect lies

Question 36

Why is confidence intervals better than P values? (HINT: there's 4 points)

Answer 36

1. Gives range of possible effect sizes 2. Embraces the value of no difference between treatments (not significantly different from control) 3. Help interpret clinical trial data by placing upper and lower bounds on true effect size 4. Statistically significant doesn't mean clinically important - the size of the effect determines importance

Question 37

What are the 3 ways to measure the effectiveness of interventions?

Answer 37

1. Number needed to treat (NNT) 2. Relative risk 3. Odds Ratio

Question 38

State the ARR and the NNT for the following: 10000 men NOT given thrombolytic treatment after heart attack - 1000 deaths after 6 weeks 10000 men given thrombolytic treatment after heart attack - 800 deaths after 6 weeks .

Answer 38

Treatment saves 200/10000 lives (=ARR) ARR = 0.02 NNT = (1/ARR) 50 => need to treat 50 people for 1 of them to avoid dying within 6 weeks

Question 39

How is the (i) probability (ii) odds calculated?

Answer 39

(i) no. favourable outcomes/ total no. possible outcomes | ii) no. favourable outcomes (successes) / no. unfavourable outcomes (failures

Question 40

What is the (i) RRR (ii) ARR?

Answer 40

(i) 1 - relative risk | ii) risk difference (divide by 100 if %

Question 41

What is the NNT the reciprocal of?

Answer 41

ARR

Question 42

What are the 5 key EBM concepts?

Answer 42

1. Evidence pyramid 2. Clinical research study designs (strengths and weaknesses) 3. Asking Qs and finding answers 4. Basic statistics (variable types, P values, CI) 5. Effectiveness of interventions (NNT, RR, odds ratio, forest plots)