Asthma. Introduc:on. Introduc:on. Anatomic Altera:ons of the Lungs. Introduc:on. RSPT 2310 Asthma RSPT 2310

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1 DMC = Degranula:on of mast cell MA = Mucus accumula:on HALV = Hyperinfla:on of alveoli MP = Mucus plug SMC = Smooth muscle constric:on RSPT 2310 Introduc:on The first evidence based asthma guidelines were published in 1991 by: Na:onal Educa:on and Preven:on Program (NAEPP) under the coordina:on of the: Na:onal Heart, Lung, and Blood Ins:tute (NHLBI) of the Na:onal Ins:tutes of Health. Introduc:on Today, the NAEPP guidelines are structured around the following four components: 1. Assessment and monitoring of asthma 2. Pa:ent educa:on 3. Control of factors contribu:ng to the asthma severity 4. The pharmacologic treatments Introduc:on The Global Ini:a:ve for (GINA) was launched in 1993 in collabora:on with the following organiza:ons: Na:onal Heart, Lung, and Blood Ins:tute (NHLBI) of the Na:onal Ins:tutes of Health, and the World Health Organiza:on (WHO) Anatomic Altera:ons of the Lungs Smooth muscle constric:on of bronchial airways (bronchospasm) Bronchial wall inflamma:on Excessive produc:on of thick, whi:sh, bronchial secre:ons Mucus plugging Hyperinfla:on of alveoli (air- trapping) In severe cases, atelectasis caused by mucus plugging 1

2 Epidemiology was firs recognized by Hippocrates more than 2000 years ago It remains one of the most common diseases encountered in clinical medicine Over the past decade the incidence of asthma has increased drama:cally It is es:mated that more than 25 million Americans have asthma Epidemiology About 500,000 Americans are hospitalized annually for severe asthma About 4000 die as a result of asthma annually According to the World Health Organiza:on, about 180,000 people worldwide die from asthma Among young children, asthma is about two :mes more prevalent in boys than girls A_er puberty, however, asthma is more common in girls Risk Factors Extrinsic asthma (Allergic or Atopic asthma) episodes clearly linked to the exposure of a specific allergen (an:gen): House dust Mites Furred animal dander Cockroach allergen Fungi Molds Yeast Risk Factors Extrinsic asthma is an immediate (Type I) anaphylac:c hypersensi:vity reac:on Extrinsic asthma is family related and usually appears in children and adults younger than 30 years old. It o_en disappears a_er puberty Because extrinsic asthma is associated with an an:gen- an:body induced bronchospasm, an immunnologic mechanism plays an important role. Risk Factors Occupa:onal sensi:zers (Occupa:onal ) Intrinsic asthma (Nonallergic or Nonatopic asthma) episode cannot be directly linked to a specific an:gen or extrinsic factor. Onset usually occurs a_er the age of 40 years 2

3 Risk Factors Obesity Sex The male sex is a risk factor for asthma in children Infec:ons Exercise- induced asthma Outdoor/Indoor air pollu:on Drugs, food addi:ves, and food preserva:ves Risk Factors Gastroesophageal reflux Sleep (nocturnal asthma) Emo:onal stress Perimenstrual asthma (catamenial asthma) Diagnosis The presence of any of these signs and symptoms should increase the suspicion of asthma: Wheezing history of any of the following: Cough, worse par:cularly at night Recurrent wheeze Recurrent difficult breathing Recurrent chest :ghtness Diagnosis Symptoms occur or worsen at night, awakening the pa:ent Symptoms occur or worsen in a seasonal padern. The pa:ent also has eczema, hay fever, or a family history of asthma or atopic diseases. Diagnosis Symptoms occur or worsen in the presence of: Animals with fur Aerosol chemicals Changes in temperature Domes:c dust mites Drugs (aspirin, beta blockers) Exercise Pollens Respiratory (viral) infec:ons Smoke Strong emo:onal expression 3

4 Diagnosis Symptoms respond to appropriate an:- asthma therapy. Pa:ent s colds go to the chest or take more than 10 days to clear up. Diagnos:c Tests Spirometry Peak expiratory flow Responsiveness to metacholine, histamine, mannitol, or exercise challenge Posi:ve skin tests with allergens or measurement of specific IgE in serum Classifica:on of Severity by Clinical Features Before Treatment Intermident Symptoms less than once a week Brief exacerba:ons Nocturnal symptoms not more than twice a month FEV 1 or PEF > 80% predicted PEF or FEV 1 variability < 20% Classifica:on of Severity by Clinical Features Before Treatment Mild Persistent Symptoms more than once a week but less than once a day Exacerba:ons may affect ac:vity and sleep Nocturnal symptoms more than twice a month FEV 1 or PEF > 80% predicted PEF or FEV 1 variability < 20-30% Classifica:on of Severity by Clinical Features Before Treatment Moderate Persistent Symptoms daily Exacerba:ons may affect ac:vity and sleep Nocturnal symptoms more than once a week Daily use of inhaled short- ac:ng β 2 - agnonist FEV 1 or PEF 60-80% predicted PEF or FEV 1 variability > 30% Classifica:on of Severity by Clinical Features Before Treatment Severe Persistent Symptoms daily Frequent nocturnal asthma symptoms Limita:on of physical ac:vi:es FEV 1 or PEF < 60% predicted PEF or FEV 1 variability > 30% 4

5 Overview of the Cardiopulmonary Clinical Manifesta:ons Associated with The following clinical manifesta:ons result from the pathophysiologic mechanisms caused (or ac:vated) by Bronchospasm Excessive Bronchial Secre:ons Clinical Data Obtained at the Pa:ent s Bedside The Physical Examination Vital Signs Increased Respiratory rate (Tachypnea) Heart rate (pulse) Blood pressure The Physical Examination (Cont d) Use of accessory muscles of inspiration Use of accessory muscles of expiration Pursed-lip breathing Substernal intercostal retractions 5

6 The Physical Examination (Cont d) The Physical Examination (Cont d) Increased anteroposterior chest diameter barrel chest Cyanosis Cough and sputum production The Physical Examination (Cont d) Chest Assessment Findings Expiratory prolongation (I:E ratio > 1:3) Decreased tactile and vocal fremitus Hyperresonant percussion not Diminished breath sounds Diminished heart sounds Wheezing and rhonchi Clinical Data Obtained from Laboratory Tests and Special Procedures Pulmonary Function Test Findings Moderate to Severe tic Episode (Obstructive Lung Pathophysiology) Forced Expiratory Flow Rate Findings Pulmonary Function Test Findings Moderate to Severe tic Episode (Obstructive Lung Pathophysiology) Lung Volume & Capacity Findings 6

7 Arterial Blood Gases tic Episode Mild to Moderate Stages Acute Alveolar Hyperventilation with Hypoxemia (Acute Respiratory Alkalosis) ph PaC0 2 HCO 3 Pa0 2 (slightly) Arterial Blood Gases tic Episode Severe Stage Acute Ventilatory Failure with Hypoxemia (Acute Respiratory Acidosis) ph PaC0 2 HCO 3 Pa0 2 (Slightly) Oxygenation Indices Moderate to Severe Stages Q S /Q T D02 V02 C(a-v)02 02ER Sv02 N N Abnormal Laboratory Tests and Procedures Sputum examination Eosinophils Charcot-Leyden crystals Casts of mucus from small airways (Kirschman spirals) IgE level (elevated in extrinsic asthma) 7

8 Radiologic Findings Chest radiograph Increased anteroposterior diameter (barrel chest) Translucent (dark) lung fields Depressed or flattened diaphragms GINA The Global Ini:a:ve for (GINA) was launched in 1993 in collabora:on with the following organiza:ons: Na:onal Heart, Lung, and Blood Ins:tute (NHLBI) of the Na:onal Ins:tutes of Health, and the World Health Organiza:on (WHO) GINA GINA s specific goals are the following: Increase awareness of asthma and its public health consequences Promote iden:fica:on of reasons for the increased prevalence of asthma Promote study of the associa:on between asthma and the environment Reduce asthma morbidity and mortality Improve management of asthma Improve availability and accessibility of effec:ve asthma therapy GINA GINA s specific goals are the following: Increase awareness of asthma and its public health consequences Promote iden:fica:on of reasons for the increased prevalence of asthma Promote study of the associa:on between asthma and the environment Reduce asthma morbidity and mortality Improve management of asthma Improve availability and accessibility of effec:ve asthma therapy GINA Provides a user friendly, evidence- based program for the management of asthma Use of the evidence- based guidelines provided by NAEPP Resources gathered worldwide from asthma experts and researchers 8

9 GINA s Five Components of Care Component 1: Develop Patient/Doctor Partnership Component 2: Identify and Reduce Exposure to Risk Factors Component 3: Assess, Treat, and Monitor Component 4: Manage Exacerbations Component 5: Special Considerations in Managing Component 1: Develop Patient/Doctor Partnership Avoid risk factors Take medications correctly Understand the difference between controller medications and reliever medications (also called rescue medications) Monitor the status using symptoms and, if relevant, PEFR Recognize signs that asthma is worsening and take action Seek medical help as appropriate Component 2: Identify and Reduce Exposure To Risk Factors Component 3: Assess, Treat, and Monitor Commonly Used to Treat Excerpts Beclomethasone dipropionate Triamcinolone acetonide Flunisolide Flunisolide hemihydrate Fluticasone propionate Ciclesonide Budesonide Mometasone Furate Inhaled Corticosteroids QVAR Azmacort Aerobid, AeroBid-M Aerospan Flovent HFA, Flovent Diskus Alvesco Pulmicort Turbuhaler Asmanex Twisthaler Prednisone Commonly Used to Treat Methylprednisolone Hydrocortisone Prednisolone Systemic Corticosteroids Deltasone Medrol, Solu-Medrol Solu-Cortef Opapred 9

10 Salmeterol Formoterol Arformoterol Commonly Used to Treat Long-Acting β 2 -Agents (LABA) Serevent Foradil Brovana Commonly Used to Treat Inhaled Corticosteroids & Long-Acting β 2 -Agents Fluticasone/sameterol Budesonide/formoterol Advair Diskus Symbicort Commonly Used to Treat Cromolyn sodium Nedocromil Mast-cell-Stabilizing Agents Intal Tilade Zafirlukast Montelukast Zileuton Commonly Used to Treat Leukotriene Inhibitors (antileukotrienes) Accolate Singulair Zyflo Omalizumab Commonly Used to Treat Monocolonal Antibody Xolair Oxtriphylline Aminophylline Dyphylline Commonly Used to Treat Xanthine Derivatives Choledyl SA Aminophylline Dylix, Lufyllin 10

11 Table 12-2 Epinephrine Reliever Medications (Rescue Medications) Commonly Used to Treat Ultra Short-Acting Bronchodilator Agents Racemic epinephrine Isoetharine Adrenaline CL Epinephrine Mist Primatene Mist MicroNefrin Isoetharine Table 12-2 Reliever Medications (Rescue Medications) Commonly Used to Treat Short-Acting Adrenergic Bronchodilator Agents (SABA) (β 2 -Agents) Metaproternol Albuterol Pributerol Levalbuterol Alupent Proventil, Ventolin, AccuNeb, Proair Maxair Autohaler Xopenex Table 12-2 Reliever Medications (Rescue Medications) Commonly Used to Treat Ipratropinum Bromide Tiotropium Antcholinergic (COPD) Atrovent Spirvia Table 12-2 Reliever Medications (Rescue Medications) Commonly Used to Treat Ipratropium and albuterol β 2 -Agents & Anticholinergic Agents Combivent, DuoNeb Component 4: Manage Exacerbations Table 12-3 Symptoms Classification of Severity of Exacerbations Excerpts Mild Moderate Severe Respiratory arrest imminent Breathless Walking Can lie down Talking Prefers sitting At rest Hunched forward Erratic resp. or apnea Talk in Sentences Phrases Words Silent 11

12 Table 12-3 Classification of Severity of Exacerbations Excerpts Table 12-3 Classification of Severity of Exacerbations Excerpts Signs Mild Moderate Severe Respiratory arrest imminent Signs Mild Moderate Severe Respiratory arrest imminent Respiratory rate Use of accessory muscles Increased Increased Often > 30/ min Erratic resp. or apneic Usually not Usually Usually Paradoxical throracoabdominal movement Wheeze Moderate, often only end expiration Loud Usually loud Absence of wheeze Pulse/min < >120 (adult) Bradycardia Component 5: Special Considerations in Managing --Excerpts Pregnancy Surgery Rhinitis, Sinusitis, and Nasal Polyps Occupational Respiratory Infection Gastroesophageal reflux Aspirin-induced asthma Anaphylaxis Respiratory Care Treatment Protocols Oxygen Therapy Protocol Bronchopulmonary Hygiene Therapy Protocol Aerosolized Medication Protocol Mechanical Ventilation Protocol 12