Asthma in the Emergency Room Presentation.pptx

Asthma in the ER setting

1. Asthma SMCH Casualty PRESENTATION DR. T.c . Katsumbe

2. "Life is a miracle and every breath we take is a gift from God. “ ~ Unknown

3. what is Asthma? Asthma is a common chronic inflammatory disease of the airways characterized by variable and recurring symptoms , reversible airflow obstruction and bronchospasm . Affects the lower respiratory tract.

4. Reasons to care about Prompt Treatment of asthma? It saves lives! Improves quality of life Prevents occurrence of unwanted complications e.g pnuemothorax

5. Pathophysiology and Disease mechanism

6. Early-Phase Response Peaks 30-60 minutes post exposure, subsides 30-90 minutes later Characterized primarily by bronchospasm Increased mucous secretion, edema formation, and increased amounts of tenacious sputum Patient experiences wheezing, cough, chest tightness, and dyspnea

7. Late-Phase Response Characterized primarily by inflammation Histamine and other mediators set up a self-sustaining cycle increasing airway reactivity causing hyper responsiveness to allergens and other stimuli Increased airway resistance leads to air trapping in alveoli and hyperinflation of the lungs If airway inflammation is not treated or does not resolve, may lead to irreversible lung damage

8. In Summary… Reduction in airway diameter Increase in airflow resistance Mediated via: Mucosal inflammation Constriction of smooth muscle Excess mucus production

9. Etiology and risk factors Asthma occurs in a familial pattern of inheritance suggesting it is an inherited disorder Atopy is the strongest predisposing factor Occupational environment Chronic exposure to airway irritants or allergens Cold air Air pollution Respiratory infections Irritants (perfumes, insecticide sprays) Excitatory state (stress ,crying, exercise)

10. CLINICAL MANIFESTATIONs The principal symptoms: wheezing and episodic shortness of breath Typical symptoms: recurrent episodes of wheezing, chest tightness breathlessness cough, with or without mucus production Typical signs: Wheezing Increased expiratory effort and prolongation (inspiration-expiration ratio of 1:2 to 1:3 or 1:4) Difficulty vocalising Hypoxia Nasal flaring Thick tenacious sputum Malaise

11. Examination of the patient during an acute attack usually reveals signs of hypoxemia Restlessness Increased anxiety Inappropriate behavior Increased pulse and blood pressure Pulsus paradoxus (drop in systolic BP during inspiratory cycle >10)

12. Remember!!! Severe attacks can have no audible wheezing due to reduction in airflow “Silent chest” is ominous sign of impending respiratory failure Potential complications: Status asthmaticus - Severe, life-threatening attack refractory to usual treatment where patient poses risk for respiratory failure Pnuemothorax Respiratory failure Respiratory acidosis Metabolic acidosis

13. Classification Severity Intermittent Mild persistent Moderate persistent Severe persistent Control Well controlled Not well controlled Very poorly controlled

14. Diagnosis History taking: A complete family, environmental, and occupational history is essential Family history: History of asthma in family Environmental history : seasonal changes, high pollen counts, mold, climate changes (particularly cold air), and air pollution Occupational history : occupation-related chemicals and compounds, including metal salts, wood and vegetable dust, industrial chemicals and plastics, biologic enzymes (e.g. laundry detergents), animal and insect dusts, sera, and secretions

15. Physical examination Diagnostic tests: Lung function tests/ pulmonary function test : Shows variable airflow limitation Blood tests : fbc , peripheral film; shows increase in the number of eosinophils in peripheral blood (> 0.4 ×109/L) Sputum micrscopy : The presence of large numbers of eosinophils in the sputum (a more useful diagnostic tool)

16. Ancillary Diagnostic tools Chest X-ray : no diagnostic features of asthma on the chest X-ray, helpful in excluding a pneumothorax or triggers such as infections Skin-prick tests (SPT) should be performed in all cases of asthma to help identify allergic causes.

17. Bronchodilators- SABA, LABA, PDEi Anti-inflammatory- corticosteroids, mast cell stabilisers , luekotriene modifiers Drug therapy

18. Bronchodilators Short acting Beta 2-adrenergic agonists (e.g. salbutamol, albuterol Acts in minutes, lasts 4 to 8 hours Short-term relief of bronchoconstriction Treatment of choice in acute exacerbations

19. Useful in preventing bronchospasm precipitated by exercise and other stimuli Overuse may cause rebound bronchospasm Too frequent use indicates poor asthma control and may mask severity

20. Long acting Beta- adrenergic receptor agonist Eg . Salmetorol 8 – 12 or 24 hr duration of action useful for nocturnal asthma Avoid contact with tongue to decrease side effects- throat irritation, nause and vomiting , diarrhea Can be used in combination therapy with inhaled corticosteroid

21. Phosphodiestrase inhibitors( PDEi ) Eg . Theophyline Inhibit PDE and thereby antagonising Adenosine receptors

22. Antiinflammatory drugs Corticosteroids (e.g., beclomethasone , fluticasone Suppress inflammatory response Inhaled form is used in long-term control Systemic form to control exacerbations and manage persistent asthma

23. Corticosteroids Do not block immediate response to allergens, irritants, or exercise Block late-phase response to subsequent bronchial hyper responsiveness Inhibit release of mediators from macrophages and eosinophil's

24. Leukotriene modifiers (e.g. Montelukast ) causes   inhibition of airway cysteinyl leukotriene receptors Have broncho -dilator and anti-inflammatory effects

25. Mast cell stabilizers (e.g., cromolyn , nedocromil ) Inhibit release of histamine Inhibit late-phase response Long-term administration can prevent and reduce bronchial hyper-reactivity Effective in exercise-induced asthma when used 10 to 20 minutes before exercise

26. Management Acute- usually in the ER setting Chronic- usually in the OPD setting

27. Acute Asthma Episode: O2 therapy should be started and monitored with pulse oximetry or ABGs in severe cases Inhaled bronchodilators Subcutaneous epinephrine 1:1000 solution or  terbutaline  is an alternative for children. Nebulized ipratropium can be co-administered with nebulized albuterol for patients who do not respond optimally to albuterol alone; Systemic Corticosteroids And MgSo4 indicated if initial response is insufficient- status asthmaticus

28. Status asthmaticus IV corticosteroids Continuous monitoring Supplemental O2 to achieve values of 90% IV fluids are given due to insensible loss of fluids Mechanical ventilation is required if there is no response to treatment

29. The End/ Magumo / Isiphetho