Asthma Flashcards
What is asthma?
- Chronic Inflammatory Airway Disease • Variable & Reversible Airway Obstruction • Airway Hyper responsiveness • Bronchial Inflammation
- Affects Children & Adults
What is the epidemiology of asthma?
• Asthma prevalence is thought to have plateaued since the late 1990s, although the UK still has some of the highest rates in Europe and on average 3 people a day die from asthma.
It affects M=F.
It is the most common long term condition in children.
What’s the aetiology of asthma?
• Environment vs Genetic
– Influence severity & responsiveness
• Environment
– Allergens / Air Pollution
– Smoking during Pregnancy
– Low air quality
– Formaldehyde (attack)
– PVC
– Indoor Allergens (dust mites / cockroaches / animal dander / mould)
– Virus
• HygieneHypothesis – Reduced expose to non pathogenic bacteria / virus
– Increased Cleanliness
– Decreased Family Size
– Exposure to bact. Endotoxin in child hood protective
– Exposure to bact. Endotoxin in adulthood may provoke bronchoconstriction
– Antiobiotic Usage – C-Section
• Genetic
• Medical Conditions – Atopic Eczema, Allergic Rhinitis, Asthma – Atopy
• Obesity • Beta Blocker - propanolol
– Cardioselective are safer • NSAIDS / ACEi
What is the pathophysiology of asthma?
– Exposure to allergen
– Cross linking of IgE
– Mast Cell Degranulation
– Histamine release
– Mucous Hypersecretion
– Vasodilation
– Oedema
– Bronchoconstriction leading to Airway Obstruction
– Late phase: mixed inflammatory cell infiltrate & acculumation leading to further bronchial hyper responsiveness
– High power: Luminal Mucous Plugs, Epithelial Shedding, Mixed Cell infiltrate, Odema, submucosal gland hyperplasia, smooth muscle hypertrophy
What would a patient’s history be like with asthma?
- Variable
- Episodes of Wheeze
- Chest Tightness
- Breathlessness
- Cough – worse in morning / night • Related to exercise / cold weather
- Associated with: GORD / OSA / Rhinosinusitis
On examination what would you find?
- Tachypnoea • Use of Accessory Muscles • Prolonged Expiratory phase • Polyphonic Wheeze • Hyperinflated chest
- Severe Attack: PEFR 110/min RR>25/min, inability to complete sentences
- Life Threatening Attack: PEFR<33%, silent chest, cyanosis, bradycardia, hypotension, confusion, coma.
Is a chest x-ray necessary?
No, unless worried about an alrernative diagnosis.
How do you measure FEV? (forced expiratory volume)
With the blowey tube thing.
What’s the blue inhaler for?
- Generally a Beta Agonist
* For Treatment of an attack
What’s the brown inhaler for?
- It’s a Preventer
* A Steroid (to reduce inflammation)
What are some non pharmacological methods to prevent asthma?
- Numerous – many with no evidence
- Breast Feeding
- Avoidance of Tobacco Smoke
- Weight Reduction
- House Dust Mites
- Allergen Specific Immunotherapy
- Buteyko Technique
What’s the pharmacological therapy for asthma?
- Aim for control: no daytime symptoms, no night time awakening, no need for rescue medication, no exacerbations, no exercise limitation, normal lung function (>80% predicted)
- Regular review, Step down treatment as required.
What’s the treatment for each severity of asthma?
- Mild intermittent asthma = Inhaled Beta Agonist PRN
- Regular Preventer Therapy = Add inhaled steroid
- Initial add – on therapy = Add LABA / Increase Steroid / Trial Alternative Agent
- Persistent Poor Control = Increase Steroid / Leukotriene RA, Theophylline, Oral Beta Agonist
- Frequent use of Oral Steroids = Oral steroid
What is the treatment process in an asthma attack?
- Oxygen(>94-98%) • Nebulised B2 Agonist • OralSteroid • Nebulised Ipratropium Bromide
- MagnesiumSulphate • Nebulised Adrenaline • Ketamine
- No Antiobiotics