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Asthma in the ERJuly 24 2014,
Antony Robert, R1 Emergency Med
Outline of the Day
● Quick review of Asthma Basics● Clinical Case
○ History○ Physical○ Differential Diagnosis○ Investigations○ Management in ER○ Discharge instructions
● Round Table with 1 new knowledge each
Asthma Basics
It is ...● chronic inflammatory disease● acute exacerbations
Cause by● Genetics● # Childhood infections and Antibiotics use● Exposure to allergens/ Western lifestyle
Asthma Basics
Chronic airway disorder● Affects Large and Small Airways
○ Mast cells, Eosinophils, T-Lymphocytes, Macrophages, Dendritic cells, Myofibroblasts, Epithelial cells
● Airway Remodelling○ Subbasement membrane thickening, ○ Subepithelial fibrosis, ○ Airway smooth muscle hypertrophy and hyperplasia,○ Angiogenesis, ○ Mucous gland hyperplasia and hypersecretion,○ with progressive, non-reversible loss of lung function
Chronic Inflammatory Disease
Continuum from Bronchospasm to Remodelling● Inflammation plays a key role ● Inhaled antigens activate ● → immunoglobulin E, mast cells, and T helper cells ● → induce inflammatory mediators and cytokines● → this initiates release of chemokines, cytokines, leukotrienes & NO
● Medications ○ (ASA, B-Blockers, NSAIDS, Sulfating, Dyes, Preservatives)
● Occupational Chemicals● Viral Infections● Indoor Antigens
○ (mold, dust mites, cockroaches, animal dander)● Exercise / cold air● Environmental Pollutants ● Emotional
Acute Exacerbations
Doctor, I have a patient in Resus
When to consider Asthma● On History
When do you consider Asthma?
● On History○ By Seasons○ Known-Asthmatic, previous admission○ Dyspnea ○ Chest tightness○ Wheezing○ Fever/Cough/Sputum○ Triggers ( MOVIEEE)
Tip for the ER
From Triage→ Likely Diagnosis
→ Likely BAD Diagnosis→ Tests to Order
→ Formulate DDx→ Focused History ( for all above)
Case : 24 y/o Man: Mateo
Its November, in ER, Gasping for air, bag with 2 puffers and advil, from south shore, was here for soccer game outdoors, during game got hit in knee, developed Dyspnea in the car, Friend drove to ER. Works at chemical plant, has 2 cats at home for the past year. Frequent episodes q 2days, worst today, cold x 1 day. Forgot puffers at home.
When do you consider Asthma?
● On Physical Exam
When do you consider Asthma?
● On Physical Exam○ Wheezing○ Hyperresonance to percussion○ Decreased breath sounds○ Prolonged expiratory phase○ Tachycardia○ Tachypnea○ Paradoxical breathing○ Pulsus paradoxus >20mmHg (severe)○ Silent chest (severe)○ Altered Mental Status
Is this Asthma
● What is the likely Diagnosis● What are the pertinent DDx?● Do we need to have a DDx?● How to come up with DDx?
Yes this is Asthma
● How to come up with DDx?○ Rule out the worst○ Remember your Pathophysiology of Asthma: Obstruction of Airway
■ From inside lumen, ■ From in the lumen walls■ From outside the lumen
○ VINDICATE
Differential diagnosis
Asthma Mimickers● Congestive Heart Failure ( Cardiac Asthma )● Upper airway Obstruction● Aspiration● Bronchogenic Ca with endobronchial obstruction● Metastatic Ca with lymphangitic metastasis● Sarcoidosis with endobronchial obstruction● Vocal cord dysfunction● Multiple pulmonary emboli
Broad Differential: IM ApproachPneumothoraxPneumoniaPulmonary EmbolismAirway Foreign Body / Foreign Body AspirationCOPDCHF Alpha1-Antitrypsin DeficiencyGERDBronchitis / Sinusitis/ Upper Respiratory Tract InfectionChurg-Strauss Syndrome ( vasculitis)NeoplasiaAortic Arch AbnormalitySarcoidosis Aspergillosis TracheomalaciaVocal Cord Dysfunction
My ER ApproachMove to Chibougamau if missed:● Pneumothorax● Pneumonia● Pulmonary Embolism● Airway Foreign Body ● Foreign Body Aspiration
No soup for you if missed● COPD● CHF ● URTI● GERD● NEOPLASIA
May get bonus pts if brought up● Sarcoidosis ● Tracheomalacia● Vocal Cord Dysfunction● Aortic Arch Abnormality● Alpha1-Antitrypsin Deficiency● Churg-Strauss Syndrome
Back to Asthma
● History +, P/E +● Labs/Exam?
Back to Asthma
● History +, P/E +● Labs/Exam
○ Spirometry○ Pulse Oximetry○ Arterial blood gas
● Assess PaCO2 ( should be low in Asthmatic)
Classification of Asthma
Mild● Dyspnea on exertion + > 70% PEF● Prompt relief with SABA
Moderate● Dyspnea limits activity + 40-69% PEF● Relief from frequent SABA + Sx for 1-2d after Oral Corticosteroids
Severe● Dyspnea at rest + PEF < 25%● Partial Relief from SABA, symptoms last > 3 days on Oral Corticosteroids
Treatment
Treatment Algorithm Round 1● PEF, FVE1 > 40%
● Start with SABA x 3 in 60 min +● ? Oral Corticosteroids
● PEF, FVE1 < 40%● Start with SABA + ● Oral Corticosteroids + Ipratropium
● Unstable● Start with SABA + ● IV Corticosteroids + Ipratropium
Treatment Algorithm Round 2● PEF, FVE1 > 40% to 69%
● Start with SABA x 1 in 60 min + ● Oral Corticosteroids
● PEF, FVE1 < 40%● Start with SABA + ● Oral Corticosteroids + Ipratropium + Adjunct
● Unstable● Admission ? ICU
Treatment Algorithm Round 3● PEF, FVE1 > 70% :
● DC HOME● PEF, FVE1 > 40% to 69% ( after 3-4 hours)
● Admit to hospital● PEF, FVE1 < 40% (after 3-4 hours) or Unstable
● Admit to ICU
Drugs● Albuterol
● relaxation of bronchial smooth muscle via Beta 2 adrenergic effect● inhibit mediator release, promote mucociliary clearance.● DOSE :
○ 2.5–5 milligrams every 20 min for three doses, ○ then 2.5–10 milligrams every 1–4 h, PRN○ or 10–15 milligrams/h as continuous nebulization.
● Ipratropium Bromide● dilate larger airways● DOSE:
○ 0.5 milligram every 20 min for three doses, then as needed.● Corticosteroids
● unclear mechanism, anti-inflammatory effect at 4-6hour● DOSE
○ Prednisone 40–80 mg/d until PEF reaches 70% or personal best.○ Methylprednisolone IV: 1 milligram/kg every 4–6 h.
Other Tx : outside this scope
● Magnesium IV (in severe Asthma)
● Heliox ( not EBM)
● Theophylline (not anymore)
● Ketamine and Halothane (not EBM)
● Mast Cell Modifiers (not in ED)
● Leukotriene Modifiers (not in ED)
● NPPV (except in Pneumothorax)
D/C Instructions
● Continue SABA● Initiate ICS (if not already on)● Continue Oral Corticosteroid● Patient Education
○ (drugs, side effects, techniques, indications, signs and symptoms)
● F/U GP in 1-4 weeks
Questions?