or more simply.. -asthma is a condition of paroxysmal reversible airway obstruction which is characterised by : Airflow limitation ( reversible) Airway hyper- responsiveness Inflammation of the bronchi

UK, 5.4 million people currently receiving treatment for asthma 1.1 million of whom are children 25% adults 20-44yrs suffer with wheeze 15% suffer from wheeze with breathlessness

Genetic / environmental influence Based on : -History : pattern of symptoms ?Exposure to tobacco/cats/exercise worsen sx -Exam : Nasal polyps/expiratory wheeze -spirometry/PEF -response to therapy

More than one of the following symptoms: wheeze, breathlessness, chest tightness and cough particularly if: -symptoms worse at night and in the early morning -symptoms in response to exercise -allergen exposure and cold air -symptoms after taking aspirin or beta blockers - History of atopic disorder - Family history of asthma and/or atopic disorder -Widespread wheeze heard on auscultation of the chest - Otherwise unexplained low FEV1 or PEF (historical or serial readings) - Otherwise unexplained peripheral blood eosinophilia

- Prominent dizziness -light-headedness -peripheral tingling -Chronic productive cough in the absence of wheeze or breathlessness -Repeatedly normal physical examination of chest when symptomatic -Voice disturbance -Symptoms with colds only -Significant smoking history (ie > 20 pack-years) -Cardiac disease -Normal PEF or spirometry when symptomatic A normal spirogram/spirometry when not symptomatic does not exclude the diagnosis of asthma. Repeated measurements of lung function are often more informative than a single assessment.

CXR/bloods FEV1= forced expiratory volume in 1 minute (reduced in restrictive and obstructive disease) FVC = forced vital capacity (Reduced in restrictive disease and obstructive disease) FEV1/FVC = normal in restrictive, reduced in obstructive disease FEV1/FVC <70% = obstructive disease -confirm reversibility of airflow obstruction -defined by improvement in FEV1 by > 12% and 400mls by the use of a short acting bronchodilator or a course of prednisolone (30mg od for 2/52)

PEF showing diurnal variability -highest daily PEFR-Lowest daily PEFR/(highest daily PEFR) diagnosis of asthma is supported if PEFR varies by at least 20% for 3 days in a week over several weeks or PEFR increases by at least 20% in response to asthma treatment. Nb : doesn’t reflect the level of lung obstruction as well as lung function testing

Clinical assessment + Spirometry (or PEF if spirometry not available)  High probablity Intermediate probablity low probablity  TREAT  FEV1/FVC 0.7 treat other condition and assess response ? Further IX  Further assessment and referral

diagnosis unclear unexpected clinical findings (ie crackles, clubbing, cyanosis, cardiac disease) unexplained restrictive spirometry suspected occupational asthma persistent non-variable breathlessness monophonic wheeze or stridor prominent systemic features (myalgia, fever, weight loss) chronic sputum production CXR shadowing marked blood eosinophilia (>1 x 10^9/l) poor response to asthma treatment severe asthma exacerbation

COPD = generally >35yrs Risk factor =smoker, regular sputum production No diurnal variation in symptoms, very little variability in PEFR FEVI<70%, FEV1/FVC<0.7 <15% response to reversibility test Single breath diffusing capacity (Lung function tests) Normal person DLC %, Reduced in COPD

Nice guidelines BTS/Sign guidelines Oxford handbook GP