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?