Bronchial asthma

1. Bronchial asthma By: NurIzzatulAshikinHarun Moderator: DrNikAzmanNikAdib

2. Outline • Definition • Diagnosis • Management and prevention 1 Develop patient-doctor relationship 2 Identify and reduce exposure to risk factor 3 Assess, treat and monitor asthma 4 Management of exacerbation • Management of life threatening asthma

3. Introduction • Asthma is a serious public health problem throughout the world • When uncontrolled, asthma can place several limits on daily life and is sometimes fatal • Early diagnosis of asthma and implementation of appropriate therapy significantly reduce the socioeconomic burden of asthma and enhance patients’ quality of life

4. Updated 2012

5. Objective • To increase awareness on asthma among health professionals, public health authorities, and the genaral public • To improve prevention and management of asthma through a concerted worldwide effort

6. GINA • Offers a framework to achieve and maintain asthma control for most patient that can be adapted to local health care systems and resources

7. Definition • Chronic inflammatory disorder of the airways associated with airway hyperreposive that leads to widespread but variable airflow obstruction that is often reversible either spontaneously or with treatment. • causes recurrent episodes of wheezing, breathlessness, chest tightness and cough, particularly at night and in the early morning.

8. Diagnosis HISTORY Wheezing - high-pitched whistling sounds when breathing out (A normal chest examination does not exclude asthma). History of any of the following: • cough, worse particularly at night/early morning • recurrent wheeze • recurrent difficulty in breathing • recurrent chest tightness Note: Eczema, hay fever, or a family history of asthma or atopic diseases is often associated with asthma.

9. Precipitating factor: Symptoms occurs or worsen in presence of: • Exercise • respiratory tract infection • animals • smoke (tobacco, wood) • pollen • changes in temperature • aerosol chemicals • drugs (aspirin, beta blockers) • dust mites (in mattress, pillows, upholstered furniture, carpets) • strong emotional expression (laughing or crying hard)

10. Symptoms respond to anti-asthmatic therapy • Patient’s cold ‘go to the chest’ or take more than 10 days to clear up

11. Lung Function Test • Spirometry • For confirmation of diagnosis • Measure the severity of air flow limitation and its reversibility • Increase in FEV1 of ≥12% and ≥ 200ml after administration of a bronchodilator indicates reversible airflow limitation consistent with asthma • PEF • For diagnosis and monitoring • PEF measurement ideally compared to the patient’s own previous best measurement • An improvement of 60L/min, or ≥20% of the pre-bronchodilator PEF after inhalation of a bronchodilator • Diurnal variation in PEF more than 20% (with twice daily readings, more than 10%)

12. Pefr chart

13. Other test: • Measurement of airway responsiveness to metacholamine and histamine • Indirect challenge test i.e. inhaled mannitol • Exercise challenge test • Skin test

14. Management and prevention 4 components to achieve and maintain control: • Develop patient-doctor relationship • Identify and reduce exposure to risk factor • Assess, treat and monitor asthma • Management of exacerbation

15. 1. Develop patient-doctor relationship • Development of partnership between patient and health care team • Avoid exposure to risk factor • Take medication correctly • Understand different between controller/reliever • Monitor symptoms, if relevant PEF • Recognize symptoms that asthma is worsening and take action • Seek medical advice as appropriate

16. 2. Identify and reduce exposure to risk factor • Domestic mites – mattress encasing • Furred animal – remove from house • Outdoor allergen – close door and window • Indoor air pollutant – avoid passive and active smoking • Occupational exposure • Food allergy • Avoid drugs – aspirin, NSAIDs, B blocker • Obesity – weight reduction

17. 3. Assess, treat and monitor asthma • Asthma is controlled when: • Patient can prevent most attack • Avoid troublesome symptoms day and night • Keep physically active • Good control is important  reduce risk of exacerbation

20. Difficult to treat • Patient who do not reach an acceptable level of control at step 4 • Symptoms not control in spite of reliever + ≥2 controllers • Consider: • Diagnosis, Compliance, Smoking, Comorbidities • Focus on achieving the best level of control

21. 4. Management of asthma exacerbation • Exacerbation? • Episodes of progressive increase in SOB, cough, wheezing, chest tightness • Characterized by reduced in expiratory airflow, as measured by FEV1 and PEF

23. High risk for asthma-related death • History of near-fatal requiring intubation / mechanical ventilation • Had history of emergency visit or hospitalization for asthma in the past year • Not currently using inhaled corticosteroid • Currently using / have recently stopped using oral glucocorticosteroid • Over-dependent on rapid-acting inhaled beta2-agonist, esp those who use >1 canister monthly • History of psychiatric disease / psychosocial problem • History of non-compliance to asthma medication

25. TREATMENT OF EXACERBATION MANAGEMENT IN ACUTE CARE MANAGEMENT IN COMMUNITY SETTING

26. MANAGEMENT IN COMMUNITY SETTNG

27. MANAGEMENT IN ACUTE CARE • Oxygen therapy • Aim SPO2 >95% • SPO2<92%  good predictor of the need for hospital admission • ABG: paO2<60mmHg with normal/increased PaCO2 (>45mmHg) indicates respiratory failure

28. Rapid acting inhaled B2 agonist • Administer at regular intervals by MDI or spacer device • Intermittent vs continuous neb  no significant difference in bronchodilator effect / hospital admission • Reasonable aproach  initial use of continuous therapy, followed by intermittent on demand therapy

29. Additional bronchodilator • Ipratropium bromide • Anti-cholinergic • Combination of nebulized B2 agonist with anti-cholinergic may produce better bronchodilation than either drug alone • Theophylline • Minimal role because the effectiveness and relative safety of rapid acting B2 agonist • Associated with severe and potentially fatal side effect (in patient with long term therapy with theophylline)

30. Systemic glucocorticosteroid • Speeds resolution of exacerbation • Should be utilized in all cases, esp: • Initial rapid acting inhaled B2 agonist therapy fails to achieve lasting improvement • The exacerbation develops even though the patient was already taking oral glucocorticosteroid • Previous exacerbations required oral glucocorticosteroid • Oral vs iv  equally effective • Course: 7days vs 14days • No need to taper down as long as pt on inhaled corticosteroid

31. Inhaled corticosteroid • Effective therapy for exacerbation • Combination of high dose inhaled glucocorticosteroid and salbutamol in acute asthma provide greater bronchodilation than salbutamol alone • Effective for prevent relapse • Discharge with prednisolone and inhaled budesonide  lower rate of relapse

32. Magnesium sulphate • IV MgSO4 2g infusion over 20min • Reduce hosp admission rates in certain patient

33. Life threatening asthma

34. Initial mx • Rapid ABC assessment • Oxygen therapy • Correct hypoxemia with high concentrations of inspired oxygen • Aim spo2> 92%

35. Nebulized B2 agonist • Short acting B2 agonist should be given repeatedly in 5mg doses or by continuous neb or 10mg/hr driven by oxygen • Administration should continue until there is significant clinical response or serious side effects

36. Nebulized ipratropium bromide • Added to nebulized B2 agonist (500mcg 4hly) • Produce significant greater bronchodilator than B2 agonist alone

37. Steroids • Systemic steroids in adequate doses should as early as possible (tables/intravenous) as it may improve survival • Inhaled/nebulized steroids do not provide additional additional benefit

38. Iv MgSO4 • Is a smooth muscle relaxant, producing bronchodilator • Single dose 1.2-2g over 20min shown to be safe and effective in acute severe asthma • Rapid administration may a/w hypotension

39. Iv bronchodilator • Should be considered in ventilated pt and those with life threatening asthma • Iv salbutamol 5-20mcg/min or terbutaline 0.05mcg/min should be titrated to response • Lactic acidosis will develop on 70% of patients after 2-4hr therapy • In extremis, salbutamol 100mcg can be given iv bolus or via ETT

40. Epinephrine • Should be considered in pt not responding adequately to measure outlined above • Route: • s/c 0.3-0.4ml 1:1000 every 20min for 3 doses • Neb 2-4ml of 1% solution hly • Iv 0.2-1mg bolus  1-10mcg/min

41. Who should be intubated & when & how should mechanical ventilation be initiated? • Bed side assessment based on assessment of risk and benefits • Absolute indications: • Coma • Respiratory collapse / cardiac arrest • Severe refractory hypoxemia

42. Relative indications • not response to initial mx • Fatigue • Somnolence • Cardiovascular compromise • Development of pneumothorax

43. Intubation • Place large ETT (≥7.5 for female, ≥8 for male) • To facilitate suctioning of mucus plugs and reduce airway resistance • Bags slowly to reduce auto-peep • Sedation and often paralysis is necessary during and after intubation

44. Mechanical ventilation • Aim • Achieve adequate oxygenation • Avoid lung hyperinflation • Buy time for medical mx to work

45. Recommended initial settings • RR 10-14/min • Vt 6-8mls/kg • Minute ventilation 8-10L/min • PEEP 0cm/H20 • Inspiratory flow 100Ls • I:E ≥1:3 • FiO2 1.0

46. Keep Pplat <30cm H2O • Keep PEEPi <12 cm H2O • Allow permissive hypercarbia

47. Sedation • Ketamine • Propofol • Fentanyl • Midazolam Neuromuscular blockade • Rocuronium / pancuronium

48. Extubation • Once airway resistance starts to fall & PaO2 normalizes, paralytic agents and sedatives should be withheld in anticipation of extubation