Asthma Summary Notes PDF

Asthma What is asthma? According to the Australian asthma handbook asthma is a chronic lung disease, which can be controlled but not cured. In clinical practice, asthma is defined by the presence of both of the following : excessive variation in lung function ('variable airflow limitatio...

Asthma What is asthma? According to the Australian asthma handbook asthma is a chronic lung disease, which can be controlled but not cured. In clinical practice, asthma is defined by the presence of both of the following : excessive variation in lung function ('variable airflow limitation' I.e. Variation in expiratory that is greater than that seen in healthy people) Respiratory symptoms (e.g. Wees, shortness of breath, cough, chest tightness) that very overtime and may be present or absent at any point in time In young children in human lung function testing is not feasible, including most preschool children, asthma is defined by the presence of variable respiratory symptoms Untreated asthma is usually characterised by chronic inflammation involving many cells and cellular elements, airway hyperresponsiveness, intermittent airway narrowing (due to bronchoconstriction, congestion or oedema of bronchial mucosa, mucus, or a combination of these. Asthma probably represents a spectrum of conditions with different pathophysiological mechanism. In order patients, there may be substantial overlap with the features of COPD. The diagnosis of allergic asthma is more likely when the person also has allergy and a family history of asthma What can trigger asthma? Diagnosis of asthma Diagnosis Triggers The diagnosis of asthma is viruses and bacteria based on a combination of: Weather history Allergens physical examination Mould considering other Exercise diagnoses Smoking documenting variable Occupational exposure airflow limitation hormonal influences Spirometry A diagnosis of asthma should be made if ALL of the following apply: the Person has a history of variable symptoms (especially cough, chest tightness, wheeze and shortness of breath) expiratory airflow limitation has been demonstrated (FEV1/FVC less than lower limit of normal for age Expiratory airflow limitation has been shown to be variable ** expiratory airflow is the rate at there are no findings that suggest an alternative diagnosis which air is exhaled from the lungs Signs and symptoms of asthma Signs Symptoms inflammation wheeze Airway obstruction Shortness of breath bronchial Chest tightness hyperresponsiveness cough Spirometry measure the volume of air (in litres) that can be inhaled and exhale over a period of time Determines how effectively air moves in and out of the airways Enables the detection of different types of lung problems Commonly used in diagnosis Also used to determine; extent of impairment Monitor response to treatment as an outcome measure in clinical studies Spirometry can assist in determining.... Obstruction If FEV1/FVC Ratio is determine that there is obstruction of the airways, and less air is able to flow through the airways less than 0.75 to 0.8 Narrow airway passage, create air turbulence and for adults and less increased resistance to airflow than 0.9 for children Restriction limits airflow during inspiration usually from loss of elasticity or physical deformities of the chest Reversible airway obstruction either spontaneous following administration or bronchodilators Asthma management and pharmacotherapy Remember SIL…. S Symbicort or SABA first < Symbicort Turbuhaler I Add ICS L Add LABA Short acting beta-agonists (SABA) Salbutamol, terbutaline Short acting beta agonists (SABA) act to relax the smooth muscle in the airways quickly. Salbutamol and Terbutaline have rapid onset of action (5 to 15 minutes) a short duration of action (3 to 6 hours) and similar efficacy. They are useful for symptom relief in asthma and COPD and prevention of exercise induced bronchoconstruction. Mode of Action Stimulate beta2 ↓ Relax bronchial smooth muscle adrenoreceptors Precautions Adverse reactions high or increasing usage of SABA indicates Tremor poorly controlled asthma and requires review Palpitations of management Headache check inhaler technique and compliance Muscle cramps regularly especially when asthma control is Tachycardia poor insomnia Counselling Points make sure that your doctor has given you an asthma action plan, and that you know what to do in an emergency Tell your doctor as soon as possible if you need to use this medicine in high or more frequently than prescribed clean the plastic mouthpiece of your inhaler at least once a week to prevent blockage of the nozzle Long-acting beta-agonists (LABA) Salmeterol, fomoterol, indacterol, oldaterol and vilanterol LABAs relax the bronchial smooth muscles over a long period of time (at least 12 hours) In asthma, LABAs are ONLY used in combination with an ICS, as LABA monotherapy is linked to an increased risk of asthma deaths In COPD , LABAs are used alone, in combination with SAMAs, LAMAs or triple therapy LABA/LAMA/ICS Mode of Action —> same as above Adverse reactions Precautions Tremor Palpitations check inhaler technique and compliance regularly when asthma is poor. Headache pregnancy Muscle cramps formoterol, salmeterol: limited experience Tachycardia but asthma control is paramount insomnia Indacterol: limited experience Counselling Points Olodaterol, vilanterol: no data, formoterol —> same as above and salmeterol preferred breastfeeding formoterol, indacterol: no human data, should be safe to use Salmeterol: safe to use Olodaterol, vilanterol: no data, fomoterol and salmeterol preferred Inhaled corticosteroids (ICS) Fluticasone, budesonide, beclametasone, ciclesonide,mometasone Mode of Action Reduce bronchial Easier to breathe and inflammation (swelling & Increase the airway > prevents asthma and mucus secretion) calibre symptoms Precautions Adverse reactions COPD: may increase risk of pneumonia oral thrush Smoking: patient who smoke may respond less rash well to ICS AND MAY REQUIRE HIGHER DOSES dysphonia Pregnant: encourage continued use of ICS. Adrenal suppression can occur with Becametasone, budesonide on fluticasone high doses preferred bone density loss: risk of osteoporosis Glaucoma, cataract: risk may be increased Counselling Points use a spacer with a PMDI to reduce risk of systemic absorption rinse mouth with water, gargling and spitting out after each dose Leukotriene receptor antagonists Montelukast Montelukast can be considered instead of an ICS space treatment, although it is less effective than regular daily low ICS for controlling asthma symptoms and reducing exacerbation risk. it can be trialed in patience who have experienced adverse affects with ICS, or who remain unwilling to use steroid based therapy. After an informed discussion with their clinician. It can also be useful in patient with coexisting allergic rhinitis, or in whom inhaled therapy is not practical. Mode of Action Leukotrienes are Blocks leukotrienes by chemicals that cause Reduces asthma inhibiting the cysteinyl & inflammation and > symptoms and leukotriene receptor constriction in the improves breathing airways Precautions Adverse reactions phenylketonuria- chewable tablets contain headache aspartame Abdominal pain Children: increased risk of neuropsychiatric Diarrhoea adverse effects eosinophilia granalomatosis with Pregnancy: may be used if needed for better polyangiitis (auto immune disease that asthma control causes inflammation of small blood Breastfeeding: safe to use vessels and damage to organs) very limited data Counselling Points take this medicine in the evening do not use this medicine to relieve symptoms of an asthma attack; follow your asthma action plan Tell your doctor if you notice a change in your moods of behaviour For chewable tablets to thoroughly before swallowing effect should be seen within days Oral corticosteroids Prednisone, prednisolone, dexamethasone The anti-inflammatory action associated with the glucocorticoid effects of oral corticosteroids is used to rapidly reduce airway inflation in severe asthma exacerbations Is indicated, start cotherapist as soon as practical, and at least within the first hour of presentation In adults should be continued for 5 to 10 days after discharge from acute care Mode of Action Reduces airway Relieve the symptoms of ↓ inflammation acute asthma exacerbations Precautions Adverse reactions breastfeeding: safe to use; avoided adrenal suppression breastfeeding for four hours after a dose to reduce the dose to the baby Sodium and water retention Latent TB- maybe reactivated Oedema Peptic ulcer disease; may increase the risk of Hypertension peptic ulcer Hypoglycaemia Diabetes; may cause hyperglycaemia and worse dyslipidaemia diabetes control Hypertension, heart failure; maybe worse due Psychiatric effects to sodium and water retention euphoria Glaucoma; intraocular pressure may increase Depression Osteoporosis; long-term use increases the risk disturbances of mood Counselling Points take the tablets or oral liquid with food to help reduce upset stomach Medication may affect your mood; may also cause sleeping problems, talk to your doctor if you have any concerns do not stop taking this medicine suddenly unless your doctor tells you so. The dose may need to be reduced gradually when stopping treatment.