Asthma

This is a short video on asthma. I created this presentation with Google Slides. Images were created or adapted from Wikimedia Commons. ADDITIONAL TAGS: USMLE Step 2 CK 2CK Step 1 Step 3 board licensing exam Experience: Study Resources and Plan | How to Get a HIGH SCORE on STEP 2 CK Pathophysiology Etiology / Triggers Signs Symptoms Diagnosis Management Drugs Acute exacerbations Overview of Asthma Reactive obstructive airway disease Combined bronchoconstriction and inflammation Allergies, Atopy, IgE → mast cell histamine mediated Related to eczema, atopic dermatitis FDA/Renée Gordon; vectors by Mysid., Public domain, via Wikimedia Commons United States-National Institute Health: National Heart, Lung, Blood Institute, triggers What the bronchoconstriction? is unknown. Risk factors Exposure Nasal polyps Eczema Frequent hospitalizations, intubations Exacerbations Virus (RSV, rhinovirus in children) Exercise Allergens (indoor outdoor) Smoke Particles Cold air Mold Stress, psychologic, emotional Acid reflux Allergic rhinitis Catamenial (in conjunction with menstrual periods) Organic compounds, like formaldehyde, some pesticides Sometimes unknown Wheeze2O.ogg: James Heilman, MD derivative work: Natural Philo symptoms Obstructive lung dz Air gets but can’t get out Increased expiratory phase respiration Wheezing, shortness breath, chest tightness, coughing Paroxysmal +/- sputum production fever (avoid oral temp tachypnea) Difficulty breathing respiratory distress status asthmaticus Use accessory muscles (intercostals) Low sounds Hyperresonant Eczema, If pt has acute onset wheezing, breath treat Most accurate: pulmonary function test (spirometry): FEV1/FVC low suggests active asthma. Give bronchodilators repeat: FEV1 improves (12%) albuterol, it’s asthma doesn’t improve, consider other normal no disease. Methacholine challenge provide drops (20%) methacholine, change, can induce (1-2%) NOTE: a synthetic form acetylcholine, which essentially same effect histamine, it induces Other tests (not routine) CBC: increased eosinophils CXR: hyperinflation serum Skin testing allergies, find potential Sputum sample: Charcot-Leyden crystals or Curschmann’s spirals ratio used bc The decreases more than FVC Treatment added stepwise fashion depending on frequency/severity asthma: Severity Symptom frequency Night-time %FEV1 predicted SABA use Intermittent ≤2/week ≤2/month ≥80% ≤2 days/week Mild persistent 2/week 3–4/month 2 dose ICS Moderate Daily 1/week 60–80% daily + LABA Severe Continuously (7/week) 60% ≥twice/day high Modified from "Asthma- Diagnosis- Classification" Wikipedia Anti-bronchoconstriction: SABA, LABA, theophylline, antimuscarinic/anticholinergic, antileukotriene Anti-inflammation: corticosteroids (inhaled oral), Class Examples Benefits Warning levalbuterol, pirbuterol Bronchodilator budesonide, beclomethasone, fluticasone, mometasone, triamcinolone, flunisolide Anti-inflammatory, systemic steroid effects formoterol, salmeterol Don’t these first without (build tolerance, reduced sensitivity) antimuscarinic tiotropium, ipratropium Decrease secretions, bronchodilator monoclonal antibodies omalizumab, reslizumab, mepolizumab Good for IgE, IL-5, comorbid allergies steroids prednisone Anti-inflammatory Osteoporosis, skin/fat changes, Cushing syndrome all asthmatics flu pneumococcal vaccine treatment Roughly increasing severity as you go down Diagnose (repeat after initial treatment) High alveolar–arterial gradient ABG peak flow (based their individual levels) An approximation FVC, since PFT isn’t done dyspnea Treat inhaler/nebulizer every 4 hours IV Supplemental O2, cannula Magnesium might help (bronchodilator) Last resort Epinephrine Endotracheal intubation