ASTHMA Victor Politi M D FACP Medical Director

ASTHMA Victor Politi, M. D. , FACP Medical Director, SVCMC School of Allied Health

What is Asthma? n Asthma is a chronic condition that occurs when the main air passages of the lungs, the bronchial tubes, become inflamed. n The muscles of the bronchial walls tighten and extra mucus is produced, causing the airways to narrow. n can lead to minor wheezing to severe difficulty in breathing. In some cases, breathing may be so labored that an asthma attack becomes life-threatening n

Definitions n Asthma – Reversible airway obstruction – Airway inflammation – Increased bronchial hyperresponsiveness n Status Asthmaticus – Severe airway obstruction developing over days-weeks

The Respiratory System

Pathophysiology n Hallmark of Asthma -Bronchial wall Hyperresponsiveness n Early Phase Asthma Reaction n Bronchoconstriction – Antigenic Stimulation of bronchial wall – Mast Cell Degranulation releases n n Histamine Chemotactics Proteolytics Heparin – Smooth Muscle Bronchoconstriction

Pathophysiology n Late Phase Asthma Reaction: Bronchial Inflammation – Inflammatory Cells Recruited n n n Neutrophils Monocytes Eosinophils – Release Cytokines, Vasoactives, Arachidonic acid – Epithelial and Endothelial Cell inflammation – Release of Interleukin 3 -6, TNF, Interferongamma

Risk Factors n n n n Family History – – One parent with asthma: up to 25% risk for child Two parents with asthma: up to 50% risk for child Parental tobacco use Associated aspirin or NSAID allergy Classic Triad: – Asthma, Nasal polyps, Aspirin allergy RSV Bronchiolitis history Strongly associated with later development of asthma Strenuous exercise in areas of high ozone (pollution)

Types of Asthma n n n Extrinsic Asthma (Allergic) Intrinsic Asthma (Non-allergic) Mixed Asthma (Extrinsic and Intrinsic) Occupational Asthma Drug Induced Asthma – Aspirin-induced Asthma – NSAID-induced Asthma n n Exercise Induced Asthma Cough Variant Asthma – Very common! (Especially in children)

Asthma Statistics n n n For reasons no one quite understands, the number of asthma cases has risen dramatically during the past decade, especially among children living in the inner city. Approximately 14 million Americans have asthma, including more than 6 million children. Asthma is the most common chronic illness of childhood. – Among young children, asthma is more common in boys than in girls. – After puberty asthma becomes more common in girls

Intrinsic Asthma Non-allergic asthma n Pathophysiology – Non-Ig. E, Non-allergic asthma n Precipitating Factors – Irritant exposure n (Air Pollution, Fumes, Perfumes, Household cleaning agents, Insecticides, paint, tobacco, cold air – Infection n URI, purulent rhinitis, acute sinusitis – GERD n Epidemiology – Much more common in adults than children – Onset age over 40 years old

Extrinsic Asthma Allergic Asthma n Pathophysiology – Ig. E mediated response to allergens n n n Immediate allergic reaction Late-phase allergic reaction Causes – Indoor allergens n House –Dust mites (most common extrinsic allergen) Animal proteins (animal dander) Mold spores Cockroaches n Pollens , mold spores n n n – Outdoor allergens n Epidemiology – Much more common in children than adults – Age Onset under 40 years old

Asthma Triggers

Asthma Triggers

Asthma Triggers

All Asthma attacks give a warning n Warning signs and symptoms for adults can include: n n n Increased shortness of breath or wheezing Disturbed sleep caused by shortness of breath, coughing or wheezing Chest tightness or pain Increased need to use bronchodilators — medications that open up airways by relaxing the surrounding muscles A fall in peak flow rates as measured by a peak flow meter

All Asthma attacks give a warning n Warning signs and symptoms for children may include – An audible whistling or wheezing when the child exhales – Coughing, especially if the cough is frequent and occurs in spasms – Waking at night with coughing or wheezing – Shortness of breath, which may or may not occur when the child exercises – A tight feeling in the child's chest

Asthma and Other Conditions n Differentiating between asthma and chronic obstructive pulmonary disease (COPD) such as emphysema and chronic bronchitis can be especially challenging. n Asthma and COPD each cause similar symptoms. n Not uncommon for older adults — especially longtime smokers — to have both conditions. n Various tests — including skin or blood tests for allergies, and spirometry — can help determine whether asthma is present.

What is cardiac asthma? Cardiac asthma isn't actually asthma. n It refers to the wheezing that's caused by CHF n – Excess fluid in the lungs (pulmonary edema) associated with heart failure causes signs and symptoms such as shortness of breath, coughing and wheezing, which mimic asthma

Exercise Induced Asthma n Exercise-induced asthma — or exerciseinduced constriction of the bronchial tubes (bronchospasm) – a condition in which the airways narrow significantly during vigorous exercise. n Typical Symptoms – Cough, Wheezing, Shortness of breath, Chest tightness – Typically symptoms present about 10 minutes after stopping exercise

Exercise Induced Asthma Exercise-induced wheezing or shortness of breath is typical for people who have chronic asthma. n But exercise-induced wheezing or shortness of breath can occur when sensitive airways constrict when exercising, especially when combined with cold air, low humidity or pollution. n

Chronic Asthma or Exercise Induced Asthma n Basic difference between chronic asthma and exercise-induced asthma – People with exercise-induced asthma have symptoms only with physical activity. – People with chronic asthma often have exercise-induced wheezing or shortness of breath, but they may have asthma symptoms at other times as well.

Exercise Induced Asthma - Medications n The most common medications for exerciseinduced asthma are bronchodilators, which are taken about 15 to 30 minutes before exercising n Medications Include: – Albuterol (Proventil, Ventolin) – Pirbuterol (Maxair) – Ipratropium and albuterol combination (Combivent)

What's the difference between asthma and COPD? n similar symptoms but very different – Asthma causes reversible lung inflammation, – COPD causes irreversible lung damage – It's important to distinguish between the two conditions because they're treated differently

What's the difference between asthma and COPD? n Smoking history. Asthma may occur in nonsmokers as well as in smokers. But COPD is usually associated with a long history of smoking

What's the difference between asthma and COPD? n Symptoms – Periodic wheezing and chest tightness, especially at night, is typical of asthma. – COPD is more likely to cause a daily morning cough that produces mucus. – In COPD, patients may develop a permanently expanded barrel chest because too much air is trapped in the lungs.

Cough Variant Asthma n Chronic cough – – Cough > 3 weeks – Nonproductive – Usually nocturnal – but can occur anytime n n Occur any age group PFTs –normal Rule out other causes of chronic cough TX – Similar to common forms of asthma

Asthma Evaluation Differential Diagnosis n n General – – All that wheezes is not asthma!! However most recurrent cough and wheeze is asthma – – – – – Allergic rhinitis sinusitis Large airway obstruction Foreign body Vocal cord dysfunction Vascular rings of laryngeal webs Laryngotracheomalacia Tracheobronchial-stenosis Enlarged lymph node or tumor Upper airway disease

Asthma Evaluation Differential Diagnosis n n Small Airway obstruction – – – Viral Bronchiolitis obliterans Cystic Fibrosis Bronchopulmonary dysplasia Heart disease Other Causes – Psychogenic cough – GERD – ACE inhibitors

Asthma Evaluation History n General: History is not always accurate – Confirm with PFTs every 3 -6 month – Patient may underplay symptoms – 10% of patients do not recognize severe Symptoms of their asthma n n n Age of onset and asthma diagnosis Past history of respiratory failure or intubation Recognize cohorts at additional risk – Elderly – Pregnancy

Asthma Evaluation History of early life injury to airways – Bronchopulmonary Dysplasia – Parental smoking n n n Disease progression Present management and response Frequency of systemic corticosteroid use – History steroid-induced complications n Comorbid conditions – Chronic sinusitis – Assess in all asthma patients – Consider empiric treatment if refractory asthma

Asthma Evaluation History n n Family History (any asthma, allergic rhinitis, etc. ) Social History – Home characteristics n n Heating and cooling system Wood burning stove Humidifier Carpeting over concrete – Smokers in home – Daycare and school situation impacting compliance

Asthma Evaluation Signs: Respiratory distress n n n Tachypnea Dyspnea Anxiety Accessory Muscle Use – Intercostal muscle use – Sternocleidomastoid use – Scalenes Muscle use Cyanosis in severe cases (lips) Tachycardia

Asthma Evaluation Radiology: chest x-ray n Indications n Low yield in acute asthma exacerbations n Status Asthmaticus or no acute asthma improvement – Initial asthma diagnosis – Abnormal findings at presentation: 5% – Abnormal findings if no improvement in 12 hours: 34% – Excludes other diagnoses n n CHF Pneumonia – Excludes complications n n Pneumothorax Pneumomediastinum

Asthma Evaluation Labs n ABGs – Hypoxemia – Hypercarbia (or normal CO 2) with decompensation n CBC – Eosinophilia may be present – Increased Levels of Ig. E may be present n Sputum Sample – – May show casts of small airways Thick mucoid sputum Curschmann's spirals Charcot-Leyden crystals

Asthma Evaluation Other Diagnostic Tests n PFT’s – Pulmonary Function Testing – Spirometry – Methacholine Challenge

What are PFT's? n n n Pulmonary function testing is one of the basic tools for evaluating a patient's respiratory status. In patients with suspected pulmonary disease, it is often the first diagnostic test employed in the work up. Pulmonary function tests (PFT's) are also used for pre-operative evaluation, managing patients with known pulmonary disease, and quantifying pulmonary disability

PFT- Spirometry n n A versatile test of pulmonary physiology. Reversibility of airways obstruction can be assessed with the use of bronchodilators. After spirometry is completed, the patient is given an inhaled bronchodilator and the test is repeated. The purpose of this is to assess whether a patient's pulmonary process is bronchodilator responsive by looking for improvement in the expired volumes and flow rates

PFT- Spirometry n n spirometry can be used to detect the bronchial hyperreactivity that characterizes asthma. By inhaling increasing concentrations of histamine or methacholine, patients with asthma will demonstrate symptoms and produce spirometric results consistent with airways obstruction at much lower threshold concentration than normal

PFT- Spirometry Normal values vary depending on gender, race, age, and height. n It is therefore not possible to interpret PFT's without such information. n There is no single set of standard reference values, however, and "normal" varies with the reference value used in each laboratory n

PFT- Spirometry Definitions n n n FEV 1 - forced expiratory volume 1 - the volume of air that is forcefully exhaled in one second. FVC - forced vital capacity - the volume of air that can be maximally forcefully exhaled FEV 1/FVC - ratio of FEV 1 to FVC, expressed as a percentage FEF 25 - 75 - forced expiratory flow - the average forced expiratory flow during the mid (25 - 75%) portion of the FVC PEF - peak expiratory flow rate - the peak flow rate during expiration

PFT- Spirometry n n In general, a > 12% increase in the FEV 1 (an absolute improvement in FEV 1 of at least 200 ml) or the FVC after inhaling a beta agonist is considered a significant response. However, the lack of an acute bronchodilator effect during spirometry does not exclude a response to long term therapy

Mild Obstruction Flow Volume Normal Flow Volume Loop

Asthma Medications n Two general types of asthma medications – Anti-inflammatory n Corticosteroids airways reduce swelling & mucous in – Bronchodilators n Relax muscle bands around airways allowing more air to flow, also increases mucous movement

Quick Relief Medications n Short acting beta-agonists – (bronchodilators that are the drug of choice to relieve asthma attack and prevent exercise-induced asthma symptoms) n Anticholinergics – (bronchodilators used in addition to short-acting beta agonists when needed or as an alternative to these drugs when needed) n Systemic corticosteroids – (anti-inflammatory drug used in an emergency to get rapid control of the disease while initiating other treatments and to speed recovery)

Status Asthmaticus Emergency Management of Asthma Exacerbation

Indications of severe attack Breathless at rest n Hunched forward n Talking in words rather than sentences n Agitated n Peak flow rate < than 60% of normal n

Status Asthmaticus n A medical emergency in which symptoms are refractory to initial bronchodilator therapy – Symptoms: chest tightness, rapidly progressive shortness of breath, dry cough, and wheezing. – Typically, patients present a few days after the onset of a viral respiratory illness, following exposure to a potent allergen or irritant, or after exercise in a cold environment.

Asthma Exacerbation Management n Step 1: Initial Assessment – Routine asthma evaluation as previously mentioned – Vital Signs (heart rate, respiratory rate, Peak Expiratory Flow Rate (PEF) or FEV 1 – O 2 saturation – Respiratory Status n n Lung auscultation Assess accessory muscle use Chest x-ray has low yield in acute exacerbations ABGs

Asthma Exacerbation Management n Inhaled short acting Beta Agonist (nebulized) n Anticholinergic (Ipratropium bromide or Atrovent) n Systemic Corticosteroid (PO or IV Indications) n – One dose up to every 20 minutes for one hour – Add to nebulized albuterol – Indication: FEV 1 or PEF <50% of predicted (Severe) – – – Severe episode (FEV 1 or PEF <50% predicted) No immediate response Oral corticosteroid recently taken by patient Oxygen indications – Adults: O 2 saturation <91% – Children: 02 saturation <96%

Additional measures for severe exacerbation n Nebulized Albuterol w/Atrovent n Systemic corticosteroid Epinephrine 0. 01 mg/kg up to 0. 3 mg SC n – hourly or continuous – May be repeated every 5 minutes n Oxygen 100% (warm, humidified) by non-rebreather mask Two Intravenous Lines n Consider : n – Aminophylline or Theophylline – Magnesium 40 mg/kg up to 2 grams IV for 1 dose n n n Rapidly effective in pediatric asthma exacerbations Also shown effective in severe adult acute asthma Some studies question benefit

Additional measures for severe exacerbation – Intubation/mechanical ventilation – – – Intubation is best done semi-electively before crisis Intubation criteria are based on clinical judgment Oral intubation is preferred n n Lower resistance and easier suctioning Lower incidence of sinusitis – Indications n n n Impending or actual respiratory arrest Extreme fatigue Altered mental status Significant respiratory distress Severe respiratory acidosis & metabolic acidosis

Medications To Be Wary Of with Asthma Patients n Many adults take multiple prescription and over-thecounter medications to treat a variety of conditions. Some medications may trigger or worsen asthma symptoms. – Angiotensin-converting enzyme (ACE) inhibitors n Won’t directly trigger asthma, can produce persistent cough causing increased wheezing – Beta blockers – NSAIDs n can trigger severe and even fatal asthma attacks

Asthma Management Goals

Asthma Management Goals Medical professionals need to be alert to the signs/symptoms of asthma n They must be able to treat asthma cases in a timely manner to avoid worsening of the condition and/or the development of status asthmaticus n

n Questions?