Respiratory 1 Flashcards
What is asthma?
Chronic inflammatory airway disease characterised by intermittent, variable airway obstruction that is usually reversible and hyper-reactivity/hypersensitivity to a variety of stimuli.
State some risk factors for asthma
- Family history of asthma or atopy
- Personal history of atopy
- Prematurity
- Low birth weight
- Parental smoking
- Viral bronchiolitis early in life
State some possible asthma triggers
- Allergens: house dust mites, animals, food
- Cold air
- Exercise
- Cigarette smoke
- Infection
- Drugs e.g. NSAIDs, beta blockers
- Emotional distress
State some features of the presentation that would suggest asthma (not asking for symptoms asking for features in history/presentation)
- Episodic symptoms with intermittent exacerbations
- Diurnal variability, typically worse at night and early morning
- Dry cough with wheeze and shortness of breath
- Typical triggers
- A history of other atopic conditions such as eczema, hayfever and food allergies
- Family history of asthma or atopy
- Bilateral widespread “polyphonic” wheeze heard by a healthcare professional
- Symptoms improve with bronchodilators
State some symptoms of asthma- highlighting the most common
- Intermittent dyspnoea
- Wheeze
- Cough (often dry)
- Chest tightness
- Chest pain
- Atopy
State 5 investigations you can use to diagnose asthma- highlighting which is first line
- Spirometry
- Spirometry with bronchodilator reversibility testing
- Fraction exhaled nitric oxide (FeNO)
- Bronchial challenge test
- Peak flow variability
*Lecturer gave in this order exactly
State 5 investigations you can use to diagnose asthma- highlighting which is first line
- Spirometry
- Spirometry with bronchodilator reversibility testing
- Fraction exhaled nitric oxide (FeNO)
- Bronchial challenge test
- Peak flow variability
What change do you need in spirometry with bronchodilator reversibility in order to diagnose asthma? (state for both children & adults)
- Children: FEV1 >/= 12%
- 17yrs & over/adults: FEV1 >/= 12% AND increase in volume (of FEV1) of at least 200mL
What FeNO level do you need to diagnose asthma in both children & adults?
- Children: >/= 35ppb
- 17yrs and over/Adults: >/= 40 ppb
Bronchial challenge test can be direct or indirect; explain difference
- Direct: nebulise a chemical that will cause irritation & constriction e.g. histmine, methacholine
- Indirect: ask them to do something to trigger symptoms e.g. get them on exercise bike
*NOTE: NICE don’t seem to recommend for children
What results would you need in peak flow variability to diagnose asthma in both children & adults
>20% in both (after 2-4 weeks monitoring peak flow at least twice per day)
State some potential side effects of inhaled corticosteroids; think about side effects of low and high dose
Common side effects of ICS:
- Headache
- Oral candidiasis
- Voice alteration
- Taste alteration
High dose ICS or prolonged treatment may lead to systemic absorption and cause side effects of systemic steroids (see image)
Asthma management uses a stepwise ladder; discuss principles of stepwise ladder
- Start at the most appropriate step for the severity of the symptoms
- Review at regular intervals based on the severity
- Step up and down the ladder based on symptoms
- Aim to achieve no symptoms or exacerbations on the lowest dose and number of treatments
- Always check inhaler technique and adherence at each review
Discuss the general management of asthma for all children (and adults)
- Assess severity/current control and future risk
- Education
- Written asthma management plan
- Management of triggers e.g. smoking, pets, hayfever, stress
- Pharmacological therapy
Discuss the management of asthma in children <5yrs
- Newly-diagnosed asthma: SABA
- Not controlled on previous step OR newly-diagnosed asthma with symptoms >= 3 / week or night-time waking: SABA + an 8-week trial of paediatric MODERATE-dose inhaled corticosteroid (ICS). After 8-weeks stop the ICS and monitor the child’s symptoms. If symptoms did not resolve during the trial period, review whether an alternative diagnosis is likely. If symptoms resolved then reoccurred within 4 weeks of stopping ICS treatment, restart the ICS at a paediatric low dose as first-line maintenance therapy. If symptoms resolved but reoccurred beyond 4 weeks after stopping ICS treatment, repeat the 8‑week trial of a paediatric moderate dose of ICS
- SABA + paediatric low-dose ICS + LTRA
- Stop the LTRA and refer to an paediatric asthma specialist
***CHECK ERS GUIDELINES/LECTURE AS HE SAID WILL STOP GIVING SABA ON IT’S OWN DUE TO INCREASED MORTALITY
Discuss the management of asthma in children aged 5-16yrs
- SABA
- SABA & paediatric low dose ICS
- SABA + paediatric low dose ICS + LTRA
- SABA + paediatric low dose ICS + LABA (and stop LTRA if it hasn’t helped)
- MART regime of paediatric low dose ICS + LABA
- MART regime (of paediatric moderate dose ICS + LABA) or fixed dose moderate dose ICS + SABA
- MART regime (of paediatric high dose ICS + LABA) or fixed dose paediatric high dose ICS + SABA OR an additional drug (e.g. theophylline)
*CHECK AS LECTURER SAID GUIDANCE CHANGING
What is MART?
Maintenance & reliever therapy
Single inhaler containing both ICS and fast acting LABA used for both daily maintenance and symptom relief as required
Definitions of what constitutes a low, moderate or high dose of ICS differs between sources; what are the NICE definitions
- low: = 200ug budesonide or equivalent
- moderate: 200-400ug budesonide or equivalent
- high: > 400ug budesonide or equivalent
State some potential side effects of SABAs/LABAs
- Tremor
- Headaches
- Nausea
- Arrhythmias e.g. tachycardia (palpitations)
- Muscle spasms
- Rash
State some potential side effects of Montelukast (an LTRA)
Common
- Diarrhoea
- Stomach ache
- URTI/sore throats
Less common
- Nightmares
- Insomnia
- Sleep walking
- Mood changes (irritability, anxiety, depression)
Parents may have concerns about ICS due to potential side effects- particularly about growth. Discuss how you could manage this in a consultation
- Give them the evidence: ICS can slightly reduce growth velocity and cause small reduction in final adult height of up to 1cm
- Explain the side effects are dose-dependent
- Put it into context: they are effective at controlling asthma; if asthma is poorly controlled may lead to asthma attacks which will require oral steroids (side effects are greater when steroids are systemic)
- If we don’t control the asthma, poorly controlled asthma can impact a child’s growth and development
- Child will have regular reviews to ensure their asthma is controlled, that they are on the minimum effective dose and that they are growing well
Describe how to use a pressurised metered dose inhaler (PMDI) without a spacer
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ICS can cause oral candidiasis; state 2 ways to reduce risk oral candidiasis
- Use a spacer
- Rinse mouth after use
State 3 advantages of using a spacer
- Easier to take medication as the medicine collects in the chamber of space and you breath it in without having to worry about getting the timing & speed right
- Helps to ensure medication is deposited into lungs and not the mouth
- Can reduce side effects (e.g. of oral candidiasis)
Asthma attacks in children can be classified/graded as moderate, acute severe & life threatening; discuss characteristics of each (in children not adults)!
Mild: PEFR >75% of best or predicted. No features of other categories
Near fatal: pCO2 rising
When wishing to step down treatment for asthma attack you must regularly review the child; discuss some things you should assess and how you might step down treatment
- Should review before next dose of their bronchodilator
- Look for: cyanosis, tracheal tug, subcostal recessions, hypoxia, tachypnoea, wheeze
- Consider monitoring serum potassium as salbutamol can cause hyperkalaemia
- If appear well, consider stepping down treatment (can do this by moving down ladder and by decreasing frequency of intervention)
- Typical step down regime of inhaled salbutamol: 10 puffs 2hrly, 10 puffs 4hrly, 6 puffs 4hrly, 4 puffs 6hrly
Describe how to use a pressurised metered dose inhaler (PMDI) with a spacer
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Describe how to use a dry powder inhaler
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How often should you clean spacers?
How often should you replace your spacer?
How should you clean them?
- Clean once a month
- Change at least yearly
- Take apart and clean with gently with warm water and a detergent (e.g. washing up liquid). Do not scrub the spacer & always allow it to airdry to avoid creating static as static ant interact with mist and prevent medication being inhaled
Discuss the management of moderate, acute severe & life-threatening asthma attacks in children
Management involves: supplementary oxygen if sats <94% or working hard, bronchodilators, steroids and antibiotics if bacterial cause suspected (e.g. amoxicillin or erythromycin). Use step wise approach:
- Salbutamol nebuliser (if acute severe), can use inhaler if mild-moderte
- Nebulised ipatropium
- Oral prednisolone (aged 1month-11year: 1-2mg/kg/day up to max of 40mg for 3/7. Aged 12-17 40-50mg/day for 5/7)
- IV hydrocortisone
- IV magnesium sulphate
- IV salbutamol
- IV aminophylline
Escalate situation early! If struggling to get control call an anaesthetist & ICU as child may require intubation & ventilation.
Once established control, you can work your way back down the ladder as child gets better.
Discuss the management of mild asthma attacks
- Can be managed as an outpatient
- With regular salbutamol inhalers via a spacer (e.g. 4-6 puffs every 4hrs)
When wishing to step down treatment for asthma attack you must regularly review the child; discuss some things you should assess and how you might step down treatment
- Should review before next dose of their bronchodilator
- Look for: cyanosis, tracheal tug, subcostal recessions, hypoxia, tachypnoea, wheeze
- Consider monitoring serum potassium as salbutamol can cause hyperkalaemia
- If appear well, consider stepping down treatment (can do this by moving down ladder and by decreasing frequency of intervention)
- Typical step down regime of inhaled salbutamol: 10 puffs 2hrly, 10 puffs 4hrly, 6 puffs 4hrly, 4 puffs 6hrly
Discuss the discharge criteria following an asthma exacerbation, which required admission, in a child
- Child is well on 4hrly salbutamol (e.g. 6 puffs 4hrly)
- Child who has severe or life threatening asthma, peak flow should be >75% best predicted & sats >94% in air (BTS/SIGN) before discharge
- Compliance and inhaler technique should be reviewed
- Written asthma management plan updated/given
- Safety netting advice should be given
- GP follow up within 2 working days
- Outpatient follow up if seen in difficult asthma clinic, life-threatening asthma attack, needed HDU/ITU or is normally on high dose ICS
Child may be sent home on 6 puffs 4hrly salbutamol; describe an example regime of how this can be reduced once they are at home
- 6 puffs 4hrly for 48hrs
- 4 puffs 6hrly for 48hrs
- 2-4 puffs as required
Discuss pathophysiology of asthma
What is meant by viral induced wheeze?
Explain why young children bet viral induced wheezes
- Wheeze caused by viral infection
- When infected with a virus the airways become inflamed; inflammation results in oedema and bronchoconstriction. Since small children’s airways have small diameters, a slight narrowing leads to a proportionally larger restriction in airflow. Wheeze is caused by air flowing through narrowed airways. We can use Poiseuille’s law to demonstrate how small change in radius causes big change in resistance to flow (then factor in a child’s already small airways)!