Bronchial Asthma

Bronchial Asthma Clinical Pearls AMR BADRELDIN HAMDY MD, FCCP

The word ‘asthma’ is Greek, meaning ‘breathless’ or to breath with open mouth .
Asthma is a syndrome that may be the result of a wide variety of structural and functional abnormalities, and the nature and extent of these may differ from patient to patient.

Different stimuli may cause different pathological changes; it is assumed that with different stimuli or in different patients, there will be heterogeneity in the involvement of different size airways as well as the airway response to these stimuli.

Asthma is a clinical syndrome characterized by increased responsiveness of the tracheobronchial tree to a variety of stimuli .
The major symptoms of asthma are paroxysms of dyspnea , wheezing and cough , which may vary from mild and almost undetectable to severe and unremitting (status asthmaticus).

The primary physiological manifestation of this hyper-responsiveness is variable airway obstruction . This can take the form of spontaneous fluctuations in the severity of obstruction following bronchodilators or corticosteroids, or increased obstruction caused by

drugs or other stimuli.
Pathologically defined , asthma is a disorder of the airways characterized by chronic inflammation with infiltration of lymphocytes , eosinophils and mast cells together with epithelial desquamation,

thickening and disorganization of the tissues of the the airway wall .
Asthma is a treatable disease with preventable morbidity. Although the cost of preventive asthma treatment seems high, the cost of not treating asthma is correctly even higher.

Asthma most often begins in early childhood, but may occur at any age.
It may develop during the first few months of life , but it is often difficult to make a definite diagnosis until the child is older.
When asthma starts in childhood, there is reasonable probability that it will remit

(sometimes temporarily) at about the time of adolescence and it usually improves at that age.
For most patients , the disease begins prior to 6 years of age. There is evidence that processes involved in sensitization may begin in utero.

The diagnosis of asthma is usually made as a result of careful history-taking , supported by a few tests or by a trial of therapy.
The history should discover the presenting symptoms , their periodicity and evolution and factors related to their variability. In particular, factors provoking

attacks should be sought.
Of particular importance in making the diagnosis of asthma is the periodicity of symptoms.
The hallmark of asthma is reversibility.
The only certain things about the course of asthma are its variability and its

unpredictability.
The course of asthma is usually one of periods of normality punctuated by attacks of cough , wheeze and dyspnea.
Seventy-five per cent are mild, 20% moderate, and 5% severe.
Death is rare.

Many mild cases remit ; moderate and severe cases tend to persist .
Thus, in order to establish the diagnosis of asthma, the clinician should determine that:
@ the patient has i ntermittent or recurring symptoms of airflow obstruction;

@ that the obstruction to airflow is reversible ;
@ that the airflow obstruction is not due to other diagnoses.

Patients with long-standing asthma have more severe obstruction than those whose disease is of recent onset.
Chronic asthma is associated with hypertrophy of mucous glands and smooth muscle , but it is more likely that the major cause is permanent obstruction

of small airways caused by contraction of the collagen deposited beneath their basement membrane.
Obliterative bronchiolitis may also contribute.

Remember that all that wheezes is not asthma .

Obstructed asthma : is characterized by asthmatic symptoms and reversibility of the FEV1 but airflow limitation persists after maximal treatment with bronchodilators and oral corticosteroids.

Persistent asthma : characterized by frequent symptoms (unless these are under control with treatment) and air-way abnormality as demonstrated by AHR to both direct and indirect stimuli and increased variability of daily peak flow readings at a time when the subject

is symptom free. This form of asthma is persistent throughout life but may go into remission during adolescence, with symptoms returning in later life.

Episodic asthma : characterized by episodes of symptom s of sufficient severity to require medication but during symptom-free interval there is no detectable AHR . It is the most common form of asthma in young children and in pollen-sensitive asthmatics.

Asthma in remission : the presence of AHR and a history of asthma needing treatment but no symptoms or treatment in the previous year are signs of asthma in remission.

Potential asthma : when there is AHR, to direct or indirect stimuli, without symptoms .

Brittle asthma : is asthma that causes little or no problem on most days but that is associated with frequent severe attacks requiring unscheduled clinic or hospital visits or frequent courses of an oral corticosteroid with its attendant side-effects.

A common feature of ‘brittle asthma’ is the apparent difficulty in controlling the variability in airway function , which is usually severe at night, with near-normal lung function during the day. Attacks occur with no obvious precipitating factors and are often life-threatening.

Extrinsic asthma : is present in an atopic subject. Such subjects can have asthma of varying severities and may have symptoms that are produced by a variety of provoking agents other than allergens.

Intrinsic asthma : asthma that is present in a person in whom no evidence of atopy can be demonstrated. This form of disease appears to start in adult life .

Asthma is the most common chronic disease of childhood. It was historically viewed as a broncho-constrictive disease and is now recognized as an inflammatory disease. The triad of reversible airway obstruction, bronchial hyperresponsiveness, and airway inflammation characterize asthma.

Questions to Consider in The Diagnosis of Asthma
Has the patient had an attack or recurrent attacks of asthma?
Does the patient have troublesome cough at night?
Does the patient have a wheeze or cough after exercise?

Does the patient have wheeze, chest tightness , or cough after exposure to air-borne allergens or pollutants?
Do the patient’s colds ‘ go to chest’ or take more than 10days to clear up?
Are symptoms improved by appropriate anti-asthma treatment? the

IUATLD Asthma Questionnaire
@ Have you had wheezing or whistling in your chest at any time?
@ Have you had an attack of shortness of breath that came on following strenuous activity at any time?
@ Have you woken up with an attack of wheezing at any time?

@ Have you woken up with an attack of coughing at any time?
@ Have you had an attack of shortness of breath that came on during the day when you were at rest at any time?

Inhaled allergens are the strongest asthma triggers. Once triggered, the inflammatory pattern is identical from the nose to the lungs . Acute signs and symptoms include rhinorhea, itching, sneezing, congestion and/or airflow obstruction.

In late phase , a wave of mediator release occurs. This predisposes to chronic inflammation with congestion, airflow obstruction, and fatigue. The late phase reaction can lower the threshold for subsequent allergen exposure.

Continuous exposure to allergen often causes irreversible disease.

Potential Risk Factors For Bronchial Asthma

Host factors:
Genetic predisposition.
Atopy
Airway hyperresponsiveness
Gender (asthma symptoms are more common in boys than in girls. Atopy develops more commonly in boys, and

boys have a smaller airway caliber in infancy).
Race/ethnicity
Environmental factors :
I. Indoor allergens
domestic mites
animal allergens

cockroach allergen
fungi, molds, yeasts
II. Outdoor allergens
Pollens
fungi, molds, yeasts
Occupational sensitizers
Tobacco smoke

Air pollution
Outdoor and indoor
Respiratory infections ( early respiratory illness is defined as a respiratory illness before the age of 2 years , severe enough to have required treatment by a doctor or at a hospital. In contrast, respiratory

Infections in late childhood or adult life have not been shown to be a risk factor for the development of the disease. Viral infections in the absence of atopy are not a risk factor of importance for the development of asthma. Nevertheless, viral infections remain important triggers of attacks , especially in atopic infants.

Parasitic infections
Socioeconomic status
Family size
Diet : breast feeding is often cited as being a protective factor.
Obesity : is a risk factor for asthma.

There are three etiologies of asthma:
allergic
non-allergic
mixed

Allergic asthma is caused by allergens and is commonly found in patients with a family history of allergies, eczema, or allergic rhinitis.
Non-allergic asthma (idiopathic asthma) is often found in patients with exposure to environmental pollutants , or with a recent viral upper respiratory infection.

Emotional factors may also serve as triggers. It includes EIB.
In mixed asthma , the etiology is a combination of allergic and non-allergic factors.

Children with one asthmatic parent have up to a 50% chance of developing asthma.
Food allergy is a rare event in asthma . It prevalence ranges from 4 to 6% in children but is less than 1% in adult asthmatic subjects.

Current or previous atopic dermatitis is frequently associated with asthma in patients with food allergy.
Dietary ingestants may include:
1. Ingested protein allergens e.g. eggs, milk, fish, wheat and nuts.
2. Food additives e.g. metabisulphite,

Sulphur dioxide, artificial colorings as tartrazine and sodium benzoate , and other preservatives.
3. Aspirin and acetylsalicylic acid .
4. Physical agents e.g. cold drinks , fizzy drinks with low pH as cola.

Improvement in hygiene and reduced recirculation of common infections is strongly associated with the increasing prevalence of atopy and atopic disease (in Western countries).

Socioeconomic and environmental factors are primarily responsible for apparent racial and ethnic differences in the prevalence of asthma.

Urban living and higher material standards of living appears to be associated with a higher prevalence of reversible airway obstruction in children. This could be due to better access to health care and increased diagnosis rates.

Damp , poorly ventilated houses with house-dust mite colonization are adverse environmental factors associated with lower socioeconomic status and inner-city living in developed countries.

Drug-induced Asthma
ACTH , ACE inhibitors ; Aspirin and other NSAID ; beta-adrenergic antagonists ; cholinergic drugs (pilocarpine); contrast media ; dextrans ; hydrocortisone.
Penicillin ; quinine ; sulphasalazine ; inhaled agents (hypotonic solutions, local anaesthetics, pentamidine)

Childhood asthma is more prevalent in boys than in girls . This is related to narrower airways , increased airway tone , and possibly higher IgE in boys , which predisposes them to enhanced airflow limitation in response to a variety of insults.

The difference disappears after the age of 10, when the airway diameter/length ratio is the same in both sexes, probably because of changes in thoracic size that occurs with puberty in males but not in females.

More females than males develop asthma during puberty and thereafter , so the prevalence of adult asthma becomes higher in females than in males.

Air pollution is defined as the atmospheric accumulation of irritants to a degree that becomes injurious to humans, animals or plants.

Environmental pollutants such as sulfur dioxide , ozone , and nitrogen oxides can, at concentrations found in heavily polluted cities, trigger bronchoconstriction , transiently increase airway responsiveness , and enhance allergic responses.

Exposure to traffic , particularly to diesel exhaust, may exacerbate pre-existing allergic conditions but does not necessarily induce the development of new cases of asthma and atopy.

Minor indoor pollutants are nitric oxide, nitrogen oxides , CO , CO2 , sulfur dioxide, formaldehyde , and biological such as endotoxins .

Sources of Indoor Pollutants
1 . Cooking with natural gas or liquid propane , which produces CO, CO2 sulfur dioxide, nitric oxide, and nitrogen oxides.
2 . Cooking on wood , kerosene , or coal-burning stoves , which produce CO, nitrogen oxides, and sulfur oxides as well as respirable particles.

3 . Heating with gas , wood, coal , and kerosene units and fireplaces, which produces CO, CO2, nitric oxide, nitrogen oxides, respirable particles, and particulate soot.
4. Building and furnishing with foam installations , glues , fireboard, pressed board , plywood, particle board , carpet

backing , and fabrics that contain volatile organic compound formaldehyde , and using paints or other materials that release isocyanates.

An important environmental factor, both for the initiation and persistence of asthma during childhood, is maternal cigarette smoking.
Smoking by a child’s mother during pregnancy plus smoking by any member of the household after the child is born increases the child’s risk of developing

asthma and wheeze.
Exposure to environmental tobacco smoke increases the risk of lower respiratory tract illness in utero, in infancy, and in childhood.

Side stream smoke, which burns hotter and is more toxic than the smoke inhaled by the tobacco user, is particularly irritating to the respiratory mucosa.

Active smoking is associated with accelerated decline of lung function in people with asthma , greater asthma severity , and poor response to asthma treatment , supporting the concept that active smoking may contribute to asthma severity.

Causes of Occupational Asthma
1. Isocyanates (plastics, paints, varnish, adhesives, printing)
2. Grains and flour (bakers, millers, farmers).
3. Laboratory animals (rats, mice, rabbits, guinea-pigs)
4. Chemicals as formaldehydes.

5. Woods (oak, western red cedar..)
6. Crustaceans (crabs, prawns).
7. Metals (cobalt, nickel).
8. Reactive dyes (Henna, proteolytic enzymes used in brewing, baking, leather industries, manufacturing of washing powders).

There is a correlation between higher body mass index and greater risk of developing asthma . Weight loss improves lung function (particularly PEF variability), symptoms, morbidity , and health status , and quality of life in obese patients with asthma.

Significant independent asthma risk factors
1. Maternal and paternal asthma.
2. Recurrent chest infections at 1 and 2y.
3. Atopy at 4 years.
4. Parental smoking at 1 year.
5. Male gender.
6. Rhinitis apart from colds.
7. Eczema during the first year of life.

Triggers of Asthma
1. Infections.
2. Allergens.
3. Occupational agents.
4. Environmental pollutants.
5. Exercise.
6. Cold air.
7. Hyperventilation.

8. Aerosols of distilled water or hypo-tonic solutions.
9. Drugs.
10. Foods.
11. Psychological factors.

Emotional stress with extreme expression of laughing, crying, anger, or fear can lead to hyperventilation and hypocapnea , which cause airway narrowing.

Acute respiratory viral infections cause asthma exacerbations in both adults and children , e.g. rhinovirus, coronavirus, influenza, parainfluenza, RSV and adenovirus.
Each respiratory virus is capable of causing almost any respiratory condition as common cold , pneumonia , bronchitis,

bronchiolitis and asthma exacerbation , depending on the site and dose of virus inoculated and the degree of host pre-disposition.
The most common respiratory viruses in infancy are respiratory syncytial viruses, which causes approximately 50% of all wheezing illnesses and 80% of cases

of bronchiolitis in this age group.
Common cold viruses as rhinoviruses, are the principal triggers of wheezing in older children and adults with asthma.
There is a clear association between severe viral respiratory infections early in life and the development of asthma in childhood.

The terms atopy, atopic state, allergy and sensitized are often used interchangeably.
Atopy is defined as the production of abnormal amounts of IgE antibodies in response to contact with environmental allergens,

is demonstrated by increased total or specific serum IgE and by a positive response to skin-prick tests using a battery of standardized allergens, specific to each geographic zone.

Allergy is increased levels of circulating IgE, specific to environmental allergens.
When both airway hyperresponsiveness and atopy are present in the patients the prevalence of asthma increases in the offspring .

Although asthma and atopy may be inherited independently, the coincidence of atopic manifestations such as eczema in one individual greatly increases the risk of asthma in her or his relatives.

Viruses appear to be more important than allergens in infancy, and allergens take on a greater role as children approach school age.

The risk of atopic parents with asthma having a child with asthma further increases when a family history of asthma is accompanied by a history of atopy.

Airway hyperresponsiveness is an abnormal response of the airways to a provoking stimulus.

Is it Asthma?

Consider asthma if the patient:
1. Has an attack or recurrent attacks of wheezing.
2. Has a troublesome cough at night .
3. Has a cough or wheeze after exercise .
4. Has a cough , wheeze, or chest tightness after exposure to airborne allergens or

pollutants.
5. Has colds that ‘ go to the chest ’ or take more than 10 days to clear up.
6. Uses anti-asthma medication.

Key indicators for asthma include the presence of history of wheeze , cough , or dyspnea ; recurrent chest tightness ; over a 20% variation in peak flow ; increased symptoms at night; increased symptoms with infection , allergens , or irritants ; weather and temperature changes ; and strong emotions.

Physical examination between exacerbations may be completely normal.
Clinical signs such as dyspnea, airflow limitation (wheeze), and hyperinflation are more likely to be present if patients are examined during symptomatic periods .

A full enquiry into asthma symptoms is not complete until details of night - time and early morning symptoms have been sought. The presence of nocturnal asthma correlates strongly with disease activity .
Nocturnal and /or early morning symptoms with a diurnal variation in

PEF of 20% or more are highly characteristic of asthma.
The prevalence of asthma symptoms in children varies from 0 to 30% in different populations.

Important areas of inquiry when taking the history
1. Age of onset.
2. Nature of symptoms (wheeze, dyspnea, cough, chest tightness).
3. Triggers.
4. Pattern of symptoms (frequency, seasonal and diurnal).
5. Severity of symptoms (previous admissions to hospital or ICU).

6. Environmental hazards and their effects on disease.
7. Drug therapy (past and present therapy including drugs, dose, devices, response and side-effects).
8. Family history (asthma and atopic illnesses in first and second degree relatives).

9. Past illness (bronchiolitis, significant respiratory illness).

The child with asthma experiences wheezing, breathlessness, chest tightness and cough. There are two stages : early response and late response.
Early response typically involves bronchoconstriction upon exposure to an allergen or other percipient. It occurs 20 minutes of exposure and may resolve in

ninety minutes.
Late response includes inflammation and increased airway responsiveness. It occurs up to f ive hours after exposure and may last days or weeks.

A group of patients whose asthma can be missed are those with cough variant asthma. These patients have chronic cough as their principal, if not only, symptom.
Some patients treated with ACE inhibitors , or with GERD , post-nasal drip , or chronic sinusitis, may develop a cough

that resembles cough variant asthma.
The prevalence of chronic sinusitis in patients with asthma is high. Thus the patients should be questioned about nasal obstruction , nasal discharge, frequent colds, day and night coughing with post-nasal drip, and sore throat.

GER is very common in patients with asthma – in some patients reflux may exacerbate respiratory symptoms, and enhance the bronchoconstriction result-ing from natural stimuli.
Half the asthmatic subjects with proven GER do not have the typical reflux symptoms of heartburn and acid regurgitation.

It is particularly important to consider reflux in the ‘asthmatic’ who appears not to respond to standard treatment for asthma.

General Appearance
Does the patient appear dyspneic? Can the patient speak in full sentences? The patient in respiratory distress may become agitated.
A patient who has become lethargic is in danger of respiratory failure .

Signs and Symptoms
Sudden onset
Wheezing
Dyspnea
Cough
Tachypnea
Mucus expectoration

Wheeze
It is a high-pitched musical sound that may be present in inspiration or expiration and audible with or without a stethoscope .
The noise is produced by air moving at a relatively high speed through an airway that is narrowed to the point of closure. The walls flutter so producing a high-

pitched musical note.
Wheeze is always accompanied by flow limitation but flow limitation is not always accompanied by wheeze.
Biphasic wheezing is associated with lower PEFR than expiratory wheeze alone.

The proportion of the respiratory cycle occupied by wheeze correlates closely with forced expiratory volume in 1 s.
High-pitched end expiratory wheeze is most typical.
In severe asthma, one may not hear a wheeze at all.

Beware the patient who has stopped wheezing, since if accompanied by lethargy, respiratory failure may be imminent.
The wheezes are usually polyphonic indicating their origin from many airways of different caliber. The cardinal feature of asthma is its variability.

Stridor or wheezing best heard in the neck suggests an alternative diagnosis , such as vocal cord dysfunction or upper airway obstruction.
The peak incidence rate of the first episode of wheezing is in the first year of life.

Cough
It is a very common complaint and not specific to asthma.
It is described as the only symptom in so called ‘cough variant asthma ’ where it is the sole manifestation of asthma thought to be characterized by central airways narrowing, the site at which cough receptors are most abundant.

Cough Complications
1. Musculoskeletal chest pain.
2. Rib fractures.
3. Subconjunctival hemorrhage.
4. Syncope.
5. Ruptured viscus.
6. Nausea and vomiting.

Dyspnea
It is not a sensitive indicator of asthma severity.
Airflow obstruction in asthma is greater during expiration than inspiration, yet only 19% of patients perceive their dyspnea to be expiratory. Dyspnea probably reflects the effort of breathing rather than airflow obstruction itself.

Vital signs are often normal, even in an acute exacerbation. One may see elevated heart and respiratory rates.

Children and adolescents with moderate and severe asthma experience anxiety depression , and restrictions on activity as compared to those with mild asthma.
Anxiety leads to rapid shallow breathing which can worsen asthma signs and symptoms .

Reduced sensitivity to hypoxia or diminished awareness of SOB can predispose youths to a potentially fatal exacerbation. The ability to perceive signs and symptoms of hypoxia appears to vary with the individual.
Patients with a low perception of dyspnea have significantly increased ED

visits, hospitalizations, near fatal exacerbations, and death as compared to patients with a normal or high perception of dyspnea.
Perception of dyspnea is defined as the identification, evaluation, and interpretation of breathing discomfort.

Markers of Fatigue
1. Subjective difficulty, ‘the asthmatic knows best’.
2. Falling oxygenation despite increasing PEFR.
3. No longer able to speak.
4. Floppy, lethargic, unable cough.

Extra-thoracic effects of increased intra-abdominal pressure
1/ GER
2/ Rectal or urethral incontinence or prolapse; vaginal prolapse.
3/ Ruptured viscus e.g. hydrocele, stomach.

Exercise-induced bronchospasm may also be a presenting symptom.
Consider asthma if a child cannot keep up with peers during athletic activity secondary to coughing or wheezing.

Nocturnal awakenings with coughing or wheezin g may be the presenting symptom especially in children. Nocturnal symptoms in a patient who has previously had only daytime symptoms represent disease progression. Circadian fluctuations in cortisol alone do not explain nocturnal symptoms.

Intense dust exposure in bedding, waning of daytime medications, postural changes, and sleep-related changes in mucociliary clearance may play a role.
Nocturnal deterioration in asthma may thus be due to:
1. Feather pillows or mites in the bed.
2. Circadian cortisol variation.

3. Increased vagal tone and reduced NANC tone acting on a hyperreactive airway at night.
4. Increased bronchial inflammation at night.

A common complaint in children with asthma ; they may have learning difficulties , irritability , and sleep disturbance.

When to refer a child to a respiratory specialist?
After a life-threatening episode or admission to an ICU.
Brittle asthma.
Asthma causing severe restriction in normal activity despite treatment.
When special investigations are needed.
More than 800ug daily ICS are needed.

Premenstrual exacerbations of asthma.
Asthma may improve, worsen, or remain unchanged during pregnancy.

Occupational Asthma
1. A defined occupational history, especially in relation to exposure to sensitizing agents.
2. Absence of asthma symptoms before beginning employment.
3. A documented relationship between development of symptoms at the work-place and reduction of these on stopping.

Mild Asthma
1. Intermittent brief symptoms less than 1-2 times/week.
2. Asymptomatic between symptoms or exacerbations.
3. Nocturnal asthma less than 2/month.
4. Limitation only on vigorous exercise.
5. Good attendance to school.

6. PEFR more than 80% predicted at baseline and PEFR variability less than 20%.
7. Minimal or no airway limitation with spirometry. Maybe little improvement in already normal flows after bronchodilator.
8. Methacholine PC20 more than 20mg/ml.

Moderate Asthma
1. Symptoms more than two attacks/week
More severe exacerbation at a rate more than 3 times/year.
2. Cough and wheeze often present.
3. Nocturnal asthma more than 2-3 times/week.
4. Diminished exercise tolerance.

5. School attendance may be affected.
6. PEFR is 60-80% and variability is 20-30%.
7. Spirometry shows mild airway obstruction, reversibility to normal after BD.
8. Methacholine PC20 between 2 and 20mg/ml.

Severe Asthma
1. Symptoms are continuous. Frequent exacerbations.
2. Cough and wheeze almost always present.
3. Nightly disturbance with early morning symptoms.
4. Marked limitation of activity.

5. Frequent loss of time from school.
6. PEFR less than 60% with variability more than 30%.
7. Spirometry shows severe airflow limi-tation, incomplete reversibility with bronchodilators, i.e. fixed obstruction.
8. Methacholine PC20 less than 2mg/ml.

An asthma exacerbation is a worsening of symptoms, which can be either abrupt in onset or gradual , but which is always associated with a decrease in expiratory airflow.
It is an episode of worsening shortness of breath , cough, wheezing or chest tightness , or some combination of all.

Exacerbations usually reflect either a failure in long-term management or exposure to a precipitating stimulus (allergic, infective or irritant).

Features of Acute Exacerbations
The most common presenting symptoms in asthmatics include shortness of breath (particularly with exertion), wheezing(which may be audible to the patient but often is not), cough (often productive secondary to inspissated secretions without necessarily being related to an infectious cause), and chest

tightness. Patients frequently feel SOB although it is not entirely clear why.
The chest is hyperinflated due to air trapping. Because of increased elastic recoil at this distended lung volume, the work of exhalation is lessened but the work of inspiration is greatly increased.

Tonic activity of the inspiratory muscles throughout inspiration and expiration has been shown in patients with asthma exacerbations, and this is a major contributor to the sensation of dyspnea.
Dyspnea can be clinically assessed by determining the effect on the patient’s speech.

Thus, exacerbations are usually associated with acute airflow limitation that can be measured with physical examination, spirometry and/ measurement of PEFR.

A sign of worsening asthma is the appearance of symptoms during the early hours of the morning, typically awakening the patient at night or being present on waking first thing in the morning.

Status asthmaticus is defined as a severe asthma exacerbation that does not respond readily to aggressive bronchodilator therapy .
Descriptive terms for status asthmaticus include life threatening asthma or near fatal asthma.

Patients with a history of current use of, or recent withdrawal from, systemic corticosteroids, hospitalization for asthma and/or emergency treatment for asthma in the past year, prior intubation for asthma, psychiatric disease or psychosocial problems and non-compliance with an asthma medication

plan are at high risk of asthma-related death . Another factor is poor access to medical care.
A subpopulation of asthmatics who may face hightend risk of death from asthma are the so-called poor perceivers . Those who are made least uncomfortable by air-way narrowing are presumed to be at a

greater risk of severe attacks requiring hospitalization or causing death, because they are simply unaware of the need of treatment until they have very little respiratory reserve.

Indications For Seeking Early Medical Help In An Exacerbation

1. High risk patient :
A. Previous history of acute-threatening attacks.
B. Hospitalization within the previous y.
C. Psychological problems.
D. Recent reduction or cessation of corticosteroids.

E. Non-compliance with recommended medical history.
F. Socio-economic factors e.g. low income inner city, poor access to medical care, cultural differences.
2. Severe exacerbations (PEFR less than 50% of predicted or personal best).

3. Response to bronchodilator lasts less than 24-48 hours.
4. No improvement within 2-6 hours of starting oral corticosteroids.
5. Further deterioration.

A group of patients in whom the diagnosis of asthma is often not made or missed is the elderly.
They are susceptible to episodes of wheezing, breathlessness, and cough caused by left ventricular failure. The presence of increased symptoms with exercise and at night may add to the diagnostic confusion.

Factors complicating the diagnosis of asthma in the elderly patients include:
1. Non-specific symptoms common to other diseases.
2. Presence of co-existing diseases.
3. Asthma versus chronic bronchitis-

-the effects of smoking.
4. Altered perception of respiratory symptoms in older patients.
5. Reduced association of asthma and atopy in the elderly.

Nocturnal cough in the elderly
Left ventricular failure
Gastro-esophageal reflux
Post-nasal drip/sinus disease

Cough in the elderly
COPD
Carcinoma
CFA

Dyspnea in the elderly
COPD
Ischemic heart disease
CFA
Carcinoma/pleural effusion
Anemia

Wheeze in the elderly
COPD
Endobronchial carcinoma

Differential Diagnosis of Asthma in the Elderly

1. Chronic bronchitis, emphysema, COAD.
2. Ischemic heart disease.
3. Congestive heart failure.
4. Cardiogenic pulmonary hypertension.
5. Malignant disease, e.g. lymphangitis granulomatosis.

6. Gastro-esophageal reflux.
7. Aspiration.
8. Pulmonary microembolism, recurrent pulmonary embolism.
9. Bronchial carcinoid tumors.
10. Drug induced bronchoconstriction.
11. Upper airway obstruction.

Upper Airway Obstruction
1. Laryngeal edema.
2. Vocal cord dysfunction.
3. Laryngeal or tracheal stenosis or malacia.
4. Primary or secondary neoplasm and foreign body.

Diagnosis of asthma in children can present a particularly difficult problem, largely because episodic wheezing and cough are among the most common symptoms encountered in childhood illnesses, particularly in children under 3 years old.

In children, there appears to be a close relationship between allergies and asthma. Many outgrow this relationship after adolescence.
Some children with asthma present only with exercise-induced symptoms. Exercise testing is helpful e.g. a 6-minute running protocol.

The presence of recurrent nocturnal cough in an otherwise healthy child should raise asthma as a probable diagnosis.
The most common cause of wheezing in young children is viral URI. The strongest predictor of wheezing continuing into asthma is atopy .

In young children with frequent wheezing, a parental history of asthma along with the presence of other atopic manifestations in the child are significantly associated with the presence of asthma at age 6 years.

Asthma Triggers in Children
1. URI s.
2. Exposure to environmental irritants and allergens.
3. Exercise.
4. Aggravating conditions such as rhinitis and sinusitis.
5. GER. 6. Stress and strong emotion.

Risk Factors for Persistence
of Asthma from Childhood
into Adult Life

1. Onset before 3 y, especially with repeated episodes in infancy.
2. Infantile eczema or allergic rhinitis.
3. Positive skin tests to airborne allergens
4. Severe disease in childhood.
5. Continued exposure to allergens (indoor).
6. Female.

The younger the child, the greater the likelihood that an alternative diagnosis may explain recurrent wheeze.
Alternative causes of recurrent wheezing in infancy include :
1. Cystic fibrosis.
2. Recurrent milk inhalation.

3. Primary ciliary dyskinesia.
4. Primary immune deficiency.
5. Congenital heart disease.
6. Foreign body aspiration.
7. Congenital malformation causing narrowing of the intra-thoracic airways.

Features that should alert the
clinician to diagnose other
than asthma

1. History
# persistent wheeze not responding to appropriate treatment.
# Wheeze associated with feeding or vomiting.
# neonatal onset of wheeze following neo-natal lung disease.

# acute onset of wheezing/coughing (suggesting foreign body).
# stridor
# productive cough
# steatorrhea.
2. Examination
# failure to thrive.

# finger clubbing
# focal signs
3. Investigations
# lack of reversibility of airflow obstruction with bronchodilators.
# persistent or focal chest X-ray changes.

Risk factors for Persistence of Asthma in Adults
1. Severe disease with fixed airway obstruction.
2. Onset after age of 40y and negative skin tests to common allergens.
3. Continued exposure to allergens after asthma has developed.
4. Continued exposure to occupational agents.

Key points in the diagnosis depends on a detailed history. Recurrent episodes of cough, wheeze and breathlessness are the key symptoms.
Viral infections and exercise are the main triggers.
Physical signs should be generalized , not focal, and are not essential to diagnosis.

Be careful when diagnosing asthma in children under one year, especially if cough is the only symptom or growth is poor.
Exposure to an allergen is an important risk factor for the development of atopic sensitization to that specific allergen, and exposure to allergens in sensitized

individuals is a risk factor for asthma exacerbations and/or the persistence of asthma symptoms.

Possible role of allergy in causing attacks of asthma
@ are the asthma symptoms seasonal or perennial?
@ Is there an association between allergen exposure and environment, e.g. at home, at work, on holiday,etc? It should be noted that symptoms may persist for several days after allergen exposure.

@ are there associated nasal, skin or eye symptoms after exposure to allergens? Remember that sensitivity to allergens is commoner in children and young adults.

Prognosis
Most children with asthma have an excellent outlook, but there is a risk of continuing disease, or after remission, of a recurrence later in life.
The onset of wheeze at an early age (under 2 years) is a poor predictor of whether asthma will persist in later child-hood.

Perhaps the most important factor as-sociated with continued asthma is the capacity to develop IgE antibody to allergens in the environment.
Other factors that predict persistence of asthma are onset before age 3 years, infantile eczema, severe childhood disease with impaired ventilatory function,

increased skin reactivity from pets or pollens, exposure to mites, pets and cockroaches in the home.
Many infants with repeated episodes of wheezing during respiratory infections, particularly boys, do, in fact grow out of asthma by school age.

A trial of treatment is probably the most confident way to make a diagnosis of asthma in children.

Factors associated with non-compliance
I. Drug factors :
1. Difficulties with inhaler devices
2. Awkward regimes ( e.g. multiple drugs
3. Side effects
4. Cost of medication.
5. Dislike of medication.
6. Distant pharmacies.

II. Non-drug factors :
1. Misunderstanding or lack of instruction.
2. Fears about side effects.
3. Inappropriate expectations.
4. Anger about condition or its treatment
5. Underestimation of severity.

6. Culture issues.
7. Forgetfulness.
8. Religious issues.

The risk of death from asthma is greater in:
1. An episode of respiratory failure requiring intubation.
2. Respiratory acidosis associated with an attack of asthma not requiring intubation.
3. Two or more hospitalizations for asthma despite chronic use of an oral

Corticosteroid.
4. Two episodes of acute pneumomediastinum or pneumothorax associated with an attack of asthma.
5. History of hospitalization or two or more ED visits for asthma in the past year.

6. Previous attacks that occurred suddenly or were associated with hypoxic seizures, hypercapnea, very low peak flow, the need for admission to an ICU.
7. The use of medications from three or more classes of therapy for asthma.

Asthma treatment should start early in life to improve outcome. Benefits of early intervention include:
1. Inflammation is controlled.
2. Low dose corticosteroids are more effective.
3. Long-term adverse effects are reduced

Remission of asthma is defined as becoming asymptomatic, with normal FEV1 and normal airway responsiveness
It is associated with better lung function and younger age at the initial presentation, together with male gender and less initial airway hyper-responsiveness.

As in children, adults with milder asthma are more likely to experience remission, but the remission rate in adults is substantially lower than in children, 10% to 15% versus over 50%.

The factors underlying increased asthma morbidity include increased severity of the disease, under-treatment of patients with anti-inflammatory therapy, over-reliance on bronchodilators, and delay in seeking medical help during an exacerbation.

Complications of Asthma
1. The most common complications relate to the long-term use of corticosteroid drugs, e.g. facial changes, skin dystrophy bruising, osteoporosis and vertebral collapse, and adrenal suppression.
2. Growth retardation in children.
3. Respiratory infections.

4. Segmental collapse.
5. Cough fractures to ribs.
6. Pulmonary hypertension and cor pulmonale and chronic hypercapnia.

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Bronchial Asthma

by cairo1957 on May 12, 2010

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Bronchial Asthma — Presentation Transcript