BRONCHIAL ASTHMA

BRONCHIAL ASTHMA


Asthma is a common chronic inflammatory disease of the airways. It is characterised by recurrent episodes of dyspnoea, cough & wheeze and is caused by reversible airways obstruction.
The 3 factors responsible for airway obstruction in asthma

Bronchial muscle contraction – cold air, smoking, allergens, beta blockers,, NSAIDs, Infection
Mucosal swelling & inflammation – mast cell & basophils releasing inflammatory mediators
Increased mucus production
Symptoms & Signs

Symptoms
Dyspnoea
Wheeze
Cough - often at night or early morning
Sputum

Signs
Tachypnoea
Audible Wheeze
Hyper-inflated Chest
Hyper-resonant percussion note
Reduced air entry noises
Widespread polyphonic wheeze
.
Severe Attack
Unable to complete sentences
Pulse >110bpm
Respiratory rate >25/min
Peak Expiratory Flow 33-50% of predicted
Accessory muscle use
.
Life threatening Attack
Silent chest - no air entry
Cyanosis
Bradycardia
Exhaustion
Confusion
Poor respiratory effort
Peak Expiratory Flow <33% of predicted
Investigations

Acute attack
Peak Expiratory Flow – decreased
ABG - reduced PaO2 & low CO2 (due to hyperventilation)
CRP – sometimes raised – non specific
Sputum Culture – pneumonia?
Blood cultures – sepsis?
CXR - infection or pneumothorax?
.
Chronic Asthma
Peak expiratory flow monitoring
.
Spirometry:
↓FEV1 but normal FVC
Decreased FEV1/FVC ratio
FEV1 improvement (>15%) after using B2 agonist

CXR - Hyperinflation of lungs
Management

Chronic Asthma

Patient education
Inhaler technique – are they correctly administering the treatment?
Lifestyle factors - smoking, passive smoking, allergies?
Importance of treatment – inhaled steroids need to be taken regular (no immediate effect)
.

Treatments are offered in a stepwise approach
1. Short acting Beta 2 Agonist – Salbutamol
2. Inhaled corticosteroid – Beclamethasome
3. Long acting beta 2 agonist – Salmeterol
4. Increase dose of inhaled steroid + Add Theophylline or Leukotriene antagonist
5. Oral prednisolone - Refer to specialist
.
Acute Asthma Attack
If mild attack then short acting B2 agonist is usually sufficient

If Severe Attack
Immediate referral to hospital by ambulance is required- 999
Inform ITU so that they are ready to respond if intubation required
Give High Flow O2 >60%
Aim for O2 saturation >92%
Nebulised High Dose B2 Agonist
If poor response to treatment add Nebulised Ipratropium
Prednisolone (40-50mg adults) – 3 to 5 days until recovery - oral or IV – reduces mortality
IV Bolus Magnesium Sulphate - used in life threatening non-responsive asthma
IV Aminophylline – life threatening non responsive asthma - consult senior as serious side effects
Intubation & specialist ITU management when - worsening hypoxia, drowsiness, unconscious
Prognosis

Half of those with childhood asthma grow out of it – due to increased bronchial diameter
Those who remain asthmatic usually find theIR asthmas severity decreases in adulthood
Some adults develop chronic asthma
Acute severe asthma attacks can have a high mortality if not treated
quickly & aggressively

http://geekymedics.com/2010/11/08/asthma/