Respiratory therapeutics Flashcards
What happens in asthmas and what are the symptoms?
bronchospasm - rapid onset,
symptoms - SOB, cough, wheeze and chest tightness (>1)
What is a key characteristic in terms of diagnosis of asthma?
variation in airflow obstruction throughout the day
What can late onset asthma be mistaken for?
HF or COPD
What factors in adults make it more likely to be a diagnose of asthma over HF/COPD?
Symptoms are worst at night or following exercise/cold exposure History of atopy FHx of asthma Wheeze on auscultation Low FEV1 or PEFR Raised eosinophils
What factors in adults makes it less likely to be asthma?
dizziness, light headedness or tingling productive cough without wheeze or SOB Normal examination and PEFR when symptomatic voice disturbance symptoms with colds only smoking history cardiac disease
What are triggers for asthma?
likely multifactorial
- allergens - dust mite and pollen
- drugs - aspirin and beta blockers
- occupational factors - isocyanates, wood resin, dyes
- environmental factors - cold air, emotion and exercise
What are the general principles of treating asthma?
avoiding triggers
treating inflammation with steroids, blocking inflammatory mediates with leukotriene antagonists and preventing bronchospasm using beta 2 agonists
What is the aim of asthma treatment?
no daytime symptoms, no night time awakenings due to symptoms, no need for rescue medication, no exacerbations, no limitations on activities and normal lung function (FEV1/PEFR>0.8)
All controlled with minimal drug side effects
What is the key aim of the stepwise approach to asthma treatment?
achieve disease control with minimal intervention
Control is maintained by stepping up treatment when necessary or stepping down when control is good
What are the 4 stages asthma?
1) minimal intermittent asthma
2) regular preventer therapy
3) initial add on therapy
4) persistent poor control
How is minimal intermittent asthma treated?
short acting beta-2 agonist (salbutamol, terbutaline)- PRN for rapid bronchodilation
Selective B2 agents only used PRN or before anticipated symptoms (before exercise)
What can high doses of beta 2 agonists cause?
no specific contraindications with minimal SE
high dose can cause tremor, tachycardia and hypokalemia
What can be done if a patient inhaler technique is poor?
teach them proper technique or it can be delivered by nebulizers, IV or orally
What is regular preventer therapy?
inhaled corticosteroids - beclometasone, fluticasone or budesonide
taken usually by inhaler twice a day at the lowest dose appropriate to the severity of asthma
When are inhaled corticosteroids prescribed to patients?
when they have had exacerbations in the last 2 years, have symptoms requiring short acting beta 2 agonist use >2/week and/or have symptoms at least one night/week
What are the adverse effects of inhaled corticosteroids?
osteoporosis at high doses, growth suppression in children, sore throat and oral thrush
thrush =common and can be reduced by using a spacer or brushing teeth after inhaler use - treated using antifungaloral suspensions or lozenges
What are the initial add on therapies?
long acting selective beta-2 agonists (salmeterol or formoterol) - long duration of action of around 12 hours- relief of reversible airway obstruction
What should long acting selective beta 2 agonists (LABAs) be taken with?
alongside corticosteroids and can sometimes be given as a combination inhaler (seretide = salmeterol+fluticasone)
When asthma is persistently poorly controlled what treatments are offered?
1st is a leukotriene receptor antagonist = montelukast or zafirlukast (oral - prophylaxis) - given particularly in exercise induced or aspirin induced - can be added to inhaled steroids if not responsive to LABAs
What are the adverse effects of leukotriene antagonists?
hypersensitivity and GI upset
Other than leukotriene antagonists what else can be used for poorly controlled asthma?
xanthine derivative e.g. modified release theophylline - limited use due to potential drug interactions and narrow therapeutic index
What are the adverse effects of xanthine derivatives?
cardiac arrhythmias and seizure
What are some of the common reasons people have poor asthma control?
poor compliance
- could be due to poor understanding or treatment, complicated regime, psychological or physical stress
May also have poor technique
Presence of triggers e.g. smoking, occupational factors, allergens
diagnosis of asthma may be wrong (GORD, COPD or bronchiectasis)
On examination of an acute severe asthma attack what is noted?
patient unable to complete sentences
chest will be quiet with high heart rate (>110) and resp rate (>25)
PEFR <0.5 predicted and they will easily tire and become dehydrated
What treatment is given for an acute severe asthma attack ?
OSHITME
- high flow oxygen
- salbutamol or terbutaline (nebulizer)
- hydrocortisone IV (100mg)/oral predisolone (40-50mg)
- ipratropium bromide (every 4-6 hours via nebulizer)
- theophylline
- magnesium (+ also intravenous b2 agonists)
- escalate
What should be given to a patient following an acute asthma attack?
nebulizers and steroids over next few days
Also important to establish reason behind attack (technique, compliance or infection)
What happens in asthma FUs?
usually at GPs with specialist asthma nurses
- adjust medications and check PEFR and symptom
What are the bronchodilators in asthma treatment?
b2 agonists
PDE inhibitors (aminophylline)
anticholinergics (ipratropium bromide)
What are the anti-inflammatories in asthma treatment?
sodium chromoglycate (stabilise mast cells)
inhaled corticosteroids (beclomethasone)
Leukotriene receptor antagonists (montelukast)
anti-igE (omalizumab)
What people is COPD diagnosis most common?
middle aged and elderly smokers
What are the symptoms of COPD?
Productive cough, alongside increase dyspnoea
What factors are looked at assessments of COPD?
How much bronchospasm, infection and emphysema the patient has as well as checking for signs of R HF
What are the 3 main groups of drug treatments for COPD?
1) Inhaled bronchodilators
2) inhaled corticosteroids
3) oral bronchodilators (theophylline)
What inhaled bronchodilators are used in COPD?
Short or long acting B2 agonists or short or long acting antimuscarincs
What is tiotropium?
long acting antimuscarinc - not used in preference of regular short acting antimuscarinics (ipratropium)
used alongside short acting B2 agonists in stage 2 treatment or long acting B2 agonists and corticosteroids in stage 3
Other than the 3 main treatments for COPD what other medications are commonly used?
antibiotics when required
annual flu vaccination and pneumococcal vaccination
When are mucolytics used?
carbocisteine is used for chronic productive cough
When are diuretics used in COPD?
Later stages given for HF and oxygen therapy should be given for resp failure
What is an essential lifestyle change in COPD?
Smoking cessation
What is particle proportional to ?
to deposition therefore smaller particles are deposited deeper into the lungs >10micrometers = mouth to large airways <5 micrometers = small airways <2micrometers = alveoli <1micrometers - may be exhaled again
What is a common form of inhaler and why?
metered dose inhalers - easy to carry around and each actuation contains a measured dose
What is the main issue with metered dose inhalers?
often people have poor technique as it requires coordination
Why are spacer devices used?
commonly used with metered dose inhalers because they reduce risk of adverse effects, no longer requires coordination
Less convenient to carry around and reduce amount of medication absorbed
How do nebulizers work?
use compressed air or ultrasonic energy to produce aerosolized particles of around 1-5 micrometers in size
only 10% of the prescribed dose actually reaches the lungs
