chapter 12 asthma

1Mosby items and derived items © 2011, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.

Chapter 12Chapter 12

AsthmaAsthma


Chapter 12Chapter 12AsthmaAsthma

Figure 12-1. Figure 12-1. Asthma.Asthma. DMC,DMC, Degranulation of mast cell; Degranulation of mast cell; HALV, HALV, hyperventilation of alveoli; hyperventilation of alveoli; M/A,M/A, mucous accumulation; mucous accumulation; MP,MP, mucous plug; mucous plug; SMC,SMC, smooth muscle constriction. smooth muscle constriction.


IntroductionIntroduction The first evidence based asthma guidelines The first evidence based asthma guidelines

were published in 1991 by:were published in 1991 by: National Asthma Education and Prevention National Asthma Education and Prevention

Program (NAEPP)—under the coordination of the:Program (NAEPP)—under the coordination of the:• National Heart, Lung, and Blood Institute (NHLBI) of the National Heart, Lung, and Blood Institute (NHLBI) of the

National Institutes of Health.National Institutes of Health.


Introduction (Cont’d)Introduction (Cont’d) Today, the NAEPP guidelines are structured Today, the NAEPP guidelines are structured

around the following four components:around the following four components:1.1. Assessment and monitoring of asthmaAssessment and monitoring of asthma2.2. Patient educationPatient education3.3. Control of factors contributing to the asthma Control of factors contributing to the asthma

severityseverity4.4. The pharmacologic treatmentsThe pharmacologic treatments


Introduction (Cont’d)Introduction (Cont’d) The Global Initiative for Asthma (GINA) was The Global Initiative for Asthma (GINA) was

launched in 1993 in collaboration with the launched in 1993 in collaboration with the following organizations:following organizations: National Heart, Lung, and Blood Institute (NHLBI) National Heart, Lung, and Blood Institute (NHLBI)

of the National Institutes of Health, and theof the National Institutes of Health, and the World Health Organization (WHO)World Health Organization (WHO)


Introduction (Cont’d)Introduction (Cont’d) GINA’s specific goals are the following:GINA’s specific goals are the following:

Increase awareness of asthma and its public Increase awareness of asthma and its public health consequenceshealth consequences

Promote identification of reasons for the Promote identification of reasons for the increased prevalence of asthmaincreased prevalence of asthma

Promote study of the association between asthma Promote study of the association between asthma and the environmentand the environment


GINA’s GoalsGINA’s Goals Reduce asthma morbidity and mortalityReduce asthma morbidity and mortality Improve management of asthmaImprove management of asthma Improve availability and accessibility of Improve availability and accessibility of

effective asthma therapyeffective asthma therapy


IntroductionIntroduction Collectively, by using the evidence-based Collectively, by using the evidence-based

guidelines provided by NAEPP, along with guidelines provided by NAEPP, along with resources gathered worldwide from asthma resources gathered worldwide from asthma experts and researchers, GINA now provides experts and researchers, GINA now provides a user friendly, evidence-based program for a user friendly, evidence-based program for the management of asthma.the management of asthma.


Introduction (Cont’d)Introduction (Cont’d) GINA’s five components of asthma care are GINA’s five components of asthma care are

presented under the general management of presented under the general management of asthma section.asthma section.


Anatomic Alterations of the LungsAnatomic Alterations of the Lungs

Smooth muscle constriction of bronchial airways (bronchospasm)

Bronchial wall inflammation Excessive production of thick, whitish,

bronchial secretions Mucus plugging Hyperinflation of alveoli (air-trapping) In severe cases, atelectasis caused by

mucus plugging


EpidemiologyEpidemiology Asthma was firs recognized by Hippocrates Asthma was firs recognized by Hippocrates

more than 2000 years agomore than 2000 years ago It remains one of the most common diseases It remains one of the most common diseases

encountered in clinical medicineencountered in clinical medicine Over the past decade the incidence of Over the past decade the incidence of

asthma has increased dramaticallyasthma has increased dramatically It is estimated that more than 25 million It is estimated that more than 25 million

Americans have asthmaAmericans have asthma


Epidemiology (Cont’d)Epidemiology (Cont’d) About 500,000 Americans are hospitalized About 500,000 Americans are hospitalized

annually for severe asthmaannually for severe asthma About 4000 die as a result of asthma About 4000 die as a result of asthma

annuallyannually According to the World Health Organization, According to the World Health Organization,

about 180,000 people worldwide die from about 180,000 people worldwide die from asthmaasthma

Among young children, asthma is about two Among young children, asthma is about two times more prevalent in boys than girlstimes more prevalent in boys than girls

After puberty, however, asthma is more After puberty, however, asthma is more common in girlscommon in girls


Risk FactorsRisk Factors Extrinsic asthma (Allergic or Atopic asthma)Extrinsic asthma (Allergic or Atopic asthma)

Asthma episodes clearly linked to the Asthma episodes clearly linked to the exposure of a specific allergen (antigen):exposure of a specific allergen (antigen):• House dustHouse dust• MitesMites• Furred animal danderFurred animal dander• Cockroach allergenCockroach allergen• FungiFungi• MoldsMolds• YeastYeast


Risk Factors (Cont’d)Risk Factors (Cont’d) Extrinsic asthma is an immediate (Type I) Extrinsic asthma is an immediate (Type I)

anaphylactic hypersensitivity reactionanaphylactic hypersensitivity reaction Extrinsic asthma is family related and usually Extrinsic asthma is family related and usually

appears in children and adults younger than appears in children and adults younger than 30 years old. 30 years old.

It often disappears after pubertyIt often disappears after puberty Because extrinsic asthma is associated with Because extrinsic asthma is associated with

an antigen-antibody induced bronchospasm, an antigen-antibody induced bronchospasm, an immunnologic mechanism plays an an immunnologic mechanism plays an important role.important role.


Figure 12-2. Figure 12-2. The immunologic mechanisms in asthma.The immunologic mechanisms in asthma.


Risk Factors (Cont’d)Risk Factors (Cont’d) Occupational sensitizers Occupational sensitizers (Occupational Asthma)(Occupational Asthma) Intrinsic asthma Intrinsic asthma (Nonallergic or Nonatopic asthma)(Nonallergic or Nonatopic asthma)

Asthma episode cannot be directly linked to a Asthma episode cannot be directly linked to a specific antigen or extrinsic factor.specific antigen or extrinsic factor.

Onset usually occurs after the age of 40 yearsOnset usually occurs after the age of 40 years


Figure 12-3. Some fFigure 12-3. Some factors known to trigger intrinsic asthma.actors known to trigger intrinsic asthma.


Risk Factors (Cont’d)Risk Factors (Cont’d)

ObesityObesity SexSex

The male sex is a risk factor for asthma in childrenThe male sex is a risk factor for asthma in children InfectionsInfections Exercise-induced asthmaExercise-induced asthma Outdoor/Indoor air pollutionOutdoor/Indoor air pollution Drugs, food additives, and food preservativesDrugs, food additives, and food preservatives


Risk Factors (Cont’d)Risk Factors (Cont’d)

Gastroesophageal refluxGastroesophageal reflux Sleep (nocturnal asthma)Sleep (nocturnal asthma) Emotional stressEmotional stress Perimenstrual asthma (catamenial asthma)Perimenstrual asthma (catamenial asthma)


Diagnosis of AsthmaDiagnosis of Asthma

The presence of any of these signs and The presence of any of these signs and symptoms should increase the suspicion of symptoms should increase the suspicion of asthma:asthma:

Wheezing—history of any of the following:Wheezing—history of any of the following: Cough, worse particularly at nightCough, worse particularly at night Recurrent wheezeRecurrent wheeze Recurrent difficult breathingRecurrent difficult breathing Recurrent chest tightnessRecurrent chest tightness


Diagnosis of Asthma (Cont’d)Diagnosis of Asthma (Cont’d)

Symptoms occur or worsen at night, Symptoms occur or worsen at night, awakening the patientawakening the patient

Symptoms occur or worsen in a seasonal Symptoms occur or worsen in a seasonal pattern.pattern.

The patient also has eczema, hay fever, or a The patient also has eczema, hay fever, or a family history of asthma or atopic diseases. family history of asthma or atopic diseases.


Diagnosis of AsthmaDiagnosis of Asthma (Cont’d)(Cont’d)

Symptoms occur or worsen in the presence Symptoms occur or worsen in the presence of:of: Animals with furAnimals with fur Aerosol chemicalsAerosol chemicals Changes in temperatureChanges in temperature Domestic dust mitesDomestic dust mites Drugs (aspirin, beta blockers)Drugs (aspirin, beta blockers) ExerciseExercise


Diagnosis of AsthmaDiagnosis of Asthma (Cont’d)(Cont’d) PollensPollens Respiratory (viral) infectionsRespiratory (viral) infections SmokeSmoke Strong emotional expressionStrong emotional expression

Symptoms respond to appropriate anti-Symptoms respond to appropriate anti-asthma therapy.asthma therapy.

Patient’s colds “go to the chest” or take more Patient’s colds “go to the chest” or take more than 10 days to clear up.than 10 days to clear up.


Test Used in the Diagnosis and Test Used in the Diagnosis and Monitoring of AsthmaMonitoring of Asthma

SpriometrySpriometry Peak expiratory flowPeak expiratory flow Responsiveness to metacholine, histamine, Responsiveness to metacholine, histamine,

mannitol, or exercise challengemannitol, or exercise challenge Positive skin tests with allergens or Positive skin tests with allergens or

measurement of specific IgE in serummeasurement of specific IgE in serum


Classification of Asthma SeverityClassification of Asthma Severityby Clinical Features Before Treatmentby Clinical Features Before Treatment

IntermittentIntermittent Symptoms less than once a weekSymptoms less than once a week Brief exacerbationsBrief exacerbations Nocturnal symptoms not more than twice a monthNocturnal symptoms not more than twice a month

• FEVFEV11 or PEF or PEF >> 80% predicted 80% predicted• PEF or FEVPEF or FEV11 variability < 20% variability < 20%


Classification of Asthma SeverityClassification of Asthma Severityby Clinical Features Before Treatmentby Clinical Features Before Treatment (Cont’d)(Cont’d)

Mild PersistentMild Persistent Symptoms more than once a week but less than Symptoms more than once a week but less than

once a dayonce a day Exacerbations may affect activity and sleepExacerbations may affect activity and sleep Nocturnal symptoms more than twice a monthNocturnal symptoms more than twice a month

• FEVFEV11 or PEF or PEF >> 80% predicted 80% predicted• PEF or FEVPEF or FEV11 variability < 20 - 30% variability < 20 - 30%


Moderate PersistentModerate Persistent Symptoms dailySymptoms daily Exacerbations may affect activity and sleepExacerbations may affect activity and sleep Nocturnal symptoms more than once a weekNocturnal symptoms more than once a week Daily use of inhaled short-acting βDaily use of inhaled short-acting β22-agnonist-agnonist

• FEVFEV11 or PEF 60 - 80% predicted or PEF 60 - 80% predicted• PEF or FEVPEF or FEV11 variability > 30% variability > 30%

Classification of Asthma SeverityClassification of Asthma Severityby Clinical Features Before Treatmentby Clinical Features Before Treatment (Cont’d)(Cont’d)


Classification of Asthma SeverityClassification of Asthma Severityby Clinical Features Before Treatment (Cont’d)by Clinical Features Before Treatment (Cont’d)

Severe PersistentSevere Persistent Symptoms dailySymptoms daily Frequent nocturnal asthma symptomsFrequent nocturnal asthma symptoms Limitation of physical activitiesLimitation of physical activities

• FEVFEV11 or PEF or PEF << 60% predicted 60% predicted• PEF or FEVPEF or FEV11 variability > 30% variability > 30%


Overview Overview of the Cardiopulmonary Clinical Manifestations of the Cardiopulmonary Clinical Manifestations

Associated with Associated with AsthmaAsthma

The following clinical manifestations result from the The following clinical manifestations result from the pathophysiologic mechanisms caused (or activated) pathophysiologic mechanisms caused (or activated) by by

Bronchospasm Excessive Bronchial Secretions


Clinical Data Obtained at the Clinical Data Obtained at the Patient’s BedsidePatient’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



Increased anteroposterior chest diameter barrel chest

Cyanosis Cough and sputum production



Pulsus paradoxus Decreased blood pressure during inspiration Increased blood pressure during expiration



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 Clinical Data Obtained from Laboratory Tests and Special Laboratory Tests and Special

ProceduresProcedures


Pulmonary Function Test FindingsModerate to Severe Asthmatic Episode

(Obstructive Lung Pathophysiology)

Forced Expiratory Flow Rate Findings

FVC FEVT FEV1/FVC ratio FEF25%-75

FEF50% FEF200-1200 PEFR MVV


Pulmonary Function Test FindingsModerate to Severe Asthmatic Episode

(Obstructive Lung Pathophysiology)

Lung Volume & Capacity Findings

VT IRV ERV RV VC

N or N or N or

IC FRC TLC RV/TLC ratio

N or N or N or


Arterial Blood GasesAsthmatic Episode

Mild to Moderate StagesAcute Alveolar Hyperventilation with Hypoxemia

(Acute Respiratory Alkalosis)

pH PaC02 HCO3 Pa02

(slightly)


PaOPaO22 and PaCO and PaCO22 trends during acute alveolar hyperventilation. trends during acute alveolar hyperventilation.


Arterial Blood GasesAsthmatic Episode

Severe StageAcute Ventilatory Failure with Hypoxemia

(Acute Respiratory Acidosis)

pH PaC02 HCO3 Pa02

(Slightly)


PaOPaO22 and PaCO and PaCO22 trends during acute or chronic ventilatory failure. trends during acute or chronic ventilatory failure.


Oxygenation IndicesModerate to Severe Stages

QS/QT 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)


Radiologic Findings

Chest radiograph Increased anteroposterior diameter (barrel chest) Translucent (dark) lung fields Depressed or flattened diaphragms


Figure 12-4. Figure 12-4. Chest x-ray film of a 2-year-old patient during an acute asthma attack.Chest x-ray film of a 2-year-old patient during an acute asthma attack.


GINA’s Five Components of Asthma Care

Component 1: Develop Patient/Doctor Partnership

Component 2: Identify and Reduce Exposure to Risk Factors

Component 3: Assess, Treat, and Monitor Asthma

Component 4: Manage Asthma Exacerbations

Component 5: Special Considerations in Managing Asthma


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

Strategies for avoiding common allergens and Strategies for avoiding common allergens and pollutants

Avoid: Tobacco smoke Drugs, foods, and additives Occupational sensitizers


Component 3: Assess, Treat, and Monitor Asthma

Assessing Asthma Control Treating to Achieve Control Monitoring to Maintain Control


Table 12-1 Controller Medications Commonly Used to Treat Asthma Excerpts

Generic Name Brand NameInhaled Corticosteroids

Beclomethasone dipropionate QVARTriamcinolone acetonide AzmacortFlunisolide Aerobid, AeroBid-MFlunisolide hemihydrate AerospanFluticasone propionate Flovent HFA, Flovent DiskusCiclesonide AlvescoBudesonide Pulmicort TurbuhalerMometasone Furate Asmanex Twisthaler


Table 12-1 Controller Medications Commonly Used to Treat Asthma Excerpts (Cont’d)

Generic Name Brand NameSystemic Corticosteroids

Prednisone DeltasoneMethylprednisolone Medrol, Solu-MedrolHydrocortisone Solu-CortefPrednisolone Opapred



Generic Name Brand NameLong-Acting β2-Agents (LABA)

Salmeterol SereventFormoterol ForadilArformoterol Brovana



Generic Name Brand NameInhaled Corticosteroids & Long-Acting β2-Agents

Fluticasone/sameterol Advair DiskusBudesonide/formoterol Symbicort



Generic Name Brand NameMast-cell-Stabilizing Agents

Cromolyn sodium IntalNedocromil Tilade



Generic Name Brand NameLeukotriene Inhibitors

(antileukotrienes)Zafirlukast AccolateMontelukast SingulairZileuton Zyflo



Generic Name Brand NameMonocolonal Antibody

Omalizumab Xolair



Generic Name Brand NameXanthine Derivatives

Oxtriphylline Choledyl SAAminophylline AminophyllineDyphylline Dylix, Lufyllin


Table 12-2 Reliever Medications (Rescue Medications) Commonly Used to Treat Asthma Excerpts (Cont’d)

Generic Name Brand NameUltra Short-Acting Bronchodilator Agents

Epinephrine Adrenaline CLEpinephrine MistPrimatene Mist

Racemic epinephrine MicroNefrinIsoetharine Isoetharine



Generic Name Brand NameShort-Acting Adrenergic Bronchodilator Agents (SABA)

(β2-Agents)

Metaproternol AlupentAlbuterol Proventil, Ventolin, AccuNeb,

ProairPributerol Maxair AutohalerLevalbuterol Xopenex



Generic Name Brand NameAntcholinergic

(COPD)Ipratropinum Bromide AtroventTiotropium Spirvia



Generic Name Brand Nameβ2-Agents & Anticholinergic Agents

Ipratropium and albuterol Combivent, DuoNeb


Component 4: Manage Asthma Exacerbations

Asthma exacerbation is defined as a progressive increase in shortness of breath, cough, wheezing, or chest tightness, or a combination of these symptoms.


Table 12-3 Classification of Severity of Asthma Exacerbations Excerpts

Mild Moderate Severe Respiratory arrest imminent

Symptoms

Breathless WalkingCan lie down

TalkingPrefers

sitting

At restHunched

forward

Erratic resp. or apnea

Talk in Sentences Phrases Words Silent




Signs

Respiratory rate

Increased Increased Often > 30/min

Erratic resp. or apneic

Use of accessory muscles

Usually not Usually Usually Paradoxical throraco-abdominal movement




Signs

Wheeze Moderate, often only end expiration

Loud Usually loud Absence of wheeze

Pulse/min < 100 100-120 >120 (adult) Bradycardia


Component 5: Special Considerations in Managing Asthma--Excerpts

Pregnancy Surgery Rhinitis, Sinusitis, and Nasal Polyps Occupational Asthma 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


Classroom Discussion

Case Study: Asthma

chapter 12 asthma

Documents