Asthma
1
2
References
3
• Pharmacotherapy: A Pathophysiologic Approach –
Chapter 33 (8th ed)
• Pharmacotherapy: Principles and Practice –
Chapter 14 (3nd ed)
• Applied Therapeutics: The Clinical Use of Drugs –
Chapter 22
• Global Initiative for Asthma (GINA) 2012.
Available from: http://www.ginasthma.org
• The National Asthma Education and Prevention
Program (NAEPP): Expert Panel Report 3,
Guidelines for the Diagnosis and Management of
Definition of Asthma
• Asthma is a chronic inflammatory disorder of the
airways in which many cells and cellular elements
play a role mast cells, eosinophils, T lymphocytes and
epithelial cells.
•
•
7
Chronic inflammation causes an associated increase in
airway hyperresponsiveness that leads to recurrent
episodes of wheezing, breathlessness, chest tightness,
and coughing, particularly at night or in the early
morning
These episodes are usually associated with
widespread but variable airflow obstruction that is
often reversible either spontaneously or with
treatment
‫• تعريف‬
‫• الربو هو مرض في الجهاز التنفسي يتميز بحدوث هجمات‬
‫متقطعة من ضيق النفس الشديد المصوت صوت تنفسي‬
‫مسموع يشبه الوزيز مع وجود فرط تحسس قصبي لمنبهات‬
‫مختلفة ومتعددة ثم تزول الهجمة بشكل تلقائي أو بالمعالجة‬
‫‪8‬‬
PATIENT PRESENTATION
• Chief Complaint
"I am failing my pharmacotherapy class. I have missed so
much time because of my asthma."
• HPI (history of present illness)
K is a 65 yo female who presents to the health service
physician complaining of increased shortness of breath,
wheezing, poor exercise tolerance, and cold started 4 days
ago. At that time, she began monitoring her peak flow
rates twice daily and implemented an action plan that
included frequent albuterol nebulizations.
Her peak flows for the past 4 days have ranged from 190 to
250 L/min and usually have been at the lower end of that
range in the morning.
9
• PMH (past medical history)
Moderate persistent asthma for 12 years; she has been
hospitalized twice in the past 2 years for asthma
exacerbations and has been to the ED 4 times in the
past 9 months
Perennial allergic rhinitis
Hypertension, CAD, Heart failure stage B, her blood
pressure is 135/85. her CAD is controlled (class1)
10
• Meds
-Ventoline HFA MD1 2puffs BID
-Beclfotre 250 MDI 1 puff QD
- Beconase Inhalation Aerosol (nasal) 1 spray each
nostril TID
- Serevent MDI 1 puffs QD
- Atenolol and captopril for Hypertension
- Prednisolone 50 mg HS
11
• Compliance with above regimen is variable; she
refills her Serevent regularly on schedule, but is
typically a few weeks late on the steroid nasal and
oral inhaler; patient obtains a Ventoline HFA MDI
approximately every 2 weeks. She frequently misses
her dose of the steroid medications and experiences
discomfort from the nasal spray.
• ROS (Review of Symptoms)
Unremarkable except for nasal stuffiness and
heartburn (possible GERD)
Patient also reports that she wakes up at least
twice a week with shortness of breath and
wheezing, and occasionally feels chest
tightness in the morning (before the acute
asthma attack)
12
• Physical examination
-Gen
Anxious-appearing white woman in apparent
distress with audible wheezing, unable to
speak in complete sentences because of
dyspnea
-VS
BP 148/88, P 105, RR 28, T 38.2°C; Wt 58 kg
-CV
Tachycardia
13
• Assessment
• 20 yo woman with moderate to severe
exacerbation of asthma precipitated by viral
upper respiratory infection
14
Pharmaceutical Care
Q1 Find out what are the reasons for exacerbations
• Check indication
• Check appropriateness of treatment
• Check dosage regimen
• Check interactions
• Check ADR
• Check knowledge
• Check Adherence
• Write down your recommendations
15
Etiology
•
Asthma is a partially heritable complex syndrome that results from a complex interaction of
genetic and environmental factors.
– Genetic predisposition (predispose individuals to, or protect them from, developing asthma)
• Atopy (genetically determined state of hypersensitivity to environmental allergens,
manifested as the presence of positive skin-prick tests or the clinical response to
common environmental allergens = genetically mediated predisposition to an excessive
IgE reaction)
• linked with metalloproteinase genes (ADAM33)
– Environmental exposure (influence susceptibility to development of asthma in predisposed
individuals, precipitate asthma exacerbations, and/or cause symptoms to persist)
• risk factors
– socioeconomic status
– family size
– tobacco smoke (Maternal smoking during pregnancy or exposure to secondhand
smoke after birth increases the risk of childhood asthma)
– allergen exposure (tree and grass pollen, house dust mites, household pets, molds)
– urbanization
– decreased exposure to common childhood infectious agents
21
• hygiene hypothesis (homework)
The "hygiene hypothesis"
 is being used to explain the increase of asthma in Western countries.
 It proposes that genetically susceptible individuals develop allergies
and asthma by allowing the allergic immunologic system (Thelper cell type 2 [TH2]-lymphocytes) to develop instead of the
immunologic system used to fight infections (T-helper cell type
1 [TH1]-lymphocytes),
 The first 2 years of life appear to be most important for the
exposures to produce an alteration in the immune response system.
 Support for the hygiene hypothesis for asthma comes from studies
demonstrating a lower risk for asthma in children who live on farms
and are exposed to high levels of bacteria, in those with a large
number of siblings, in those with early enrollment into child care,
in those with exposure to cats and dogs early in life, or in those
with exposure to fewer antibiotics.
MECHANISMS OF ASTHMA
•The current concept of asthma pathogenesis is that a characteristic
chronic inflammatory process involving the airway wall causes the
development of airflow limitation (bronchospasm, edema,
hypersecreation) and increased airway responsiveness, the latter of
which predisposes the airways to narrow in response to a variety of
stimuli.
•Characteristic features of the airway inflammation are increased
numbers of activated eosinophils, mast cells, macrophages, and T
lymphocytes in the airway mucosa and lumen.
• In parallel with the chronic inflammatory process, injury of the
bronchial epithelium stimulates processes of repair that
result in structural and functional changes referred to as
“remodeling”.
28
Airway remodeling refers to structural changes,
including an alteration in the amount and
composition of the extracellular matrix in the
airway wall leading to airflow obstruction that
eventually may become only partially reversible
29
Asthma: Pathological changes
34
Diagnosis of asthma
Symptoms (episodic/variable)
• wheeze
• shortness of breath
• chest tightness
• cough
Consider the diagnosis of
asthma in patients with
some or all of these features
38
Diagnosis of asthma
Symptoms (episodic/variable)
• wheeze
• shortness of breath
• chest tightness
• cough
Signs
• none (common)
• wheeze –expiratory (
inspiratory)
• Tachypnea
Consider the diagnosis of
asthma in patients with
some or all of these features
39
Diagnosis of asthma
Symptoms (episodic/variable)
• wheeze
• shortness of breath
• chest tightness
• cough
Signs
• none (common)
• wheeze – diffuse, bilateral,
expiratory ( inspiratory)
• tachypnea
Consider the diagnosis of
asthma in patients with
some or all of these features
Helpful additional information
• personal/family history of asthma or atopy
• history of worsening after aspirin/NSAID,
 blocker use
• recognised triggers – pollens, dust, animals,
exercise, viral infections, chemicals, irritants
• pattern and severity of symptoms and
exacerbations
41
Objective measurements
• >20% diurnal variation on 3 days in
a week for 2 weeks on PEF diary
• or FEV1 12% (and 200ml) increase after
short acting ß2 agonist or steroid tablets
• or FEV1 12% decrease after 6 minutes of
running exercise
• histamine or methacholine challenge in
difficult cases
Spirometry ‫ياس التَّنَفُّس‬
ُ ‫ق‬
• Spirometry is preferred for diagnostic testing, and
should be used for both diagnosis and assessment
of progress.
• The aim of spirometry in general practice is to assess
variability of airflow obstruction, and to measure the
degree of airflow obstruction compared to predicted
normal.
42
Spirometry (Homework)






Lung volumes often are measured to obtain information
about the size of the patient's lungs, because pulmonary
diseases can affect the volume of air that can be inhaled
and exhaled.
The tidal volume is the volume of air inspired or expired
during normal breathing.
The volume of air blown off after maximal inspiration to
full expiration is defined as the vital capacity (VC).
The residual volume (RV) is the volume of air left in the
lung after maximal expiration.
The volume of air left after a normal expiration is the
functional residual capacity (FRC).
Total lung capacity (TLC) is the VC plus the RV.
 Patients with obstructive lung disease have difficulty with expiration; therefore, they tend to
have a decreased VC, an increased RV, and a normal TLC.
 Classic restrictive lung diseases (e.g., sarcoidosis, idiopathic pulmonary fibrosis) present with
decrements in all lung volumes.
 Patients also may have mixed lesion diseases, in which case the classic findings are not apparent
until the disease has advanced considerably.
 The spirometer also can be used to evaluate the performance of the patient's lungs, thorax, and
respiratory muscles in moving air into and out of the lungs. Forced expiratory maneuvers amplify
the ventilation abnormalities produced.
44
45
45
47
Peak Expiratory Flow
Peak expiratory flow (PEF)
measurements can be an
important aid in both diagnosis
and monitoring of asthma. HOW?

The PEF is the maximal flow that can be produced during the forced expiration.

The PEF can be measured easily with various handheld peak flow meters and commonly is used in
emergency departments (EDs) and clinics to quickly and objectively assess the effectiveness of bronchodilators
in the treatment of acute asthma attacks. Peak flow meters also can be used at home by patients with asthma to
assess chronic therapy.
 PEF measurements are ideally compared to the patient’s own previous best measurements using
his/her own peak flow meter.

The changes in PEF generally parallel those of the FEV1; however, the PEF is a less reproducible
measure than the FEV1.

A healthy, average-sized young adult male typically has a PEF of 550 to 700 L/minute.
Classification of Severity
53
Factors Affecting Asthma Severity
 Major factors that may contribute to the severity of asthma include:
 allergens typically associated with atopy;
 chemical exposures in occupational environments;
 exposure to: tobacco smoke, irritants, and indoor and outdoor pollution.
 Other factors include:
 Rhinitis: intranasal corticosteroids may improve asthma symptoms
 Acute and chronic sinusitis: antibiotic therapy of sinusitis may improve asthma





symptoms.
Nasal polyps are associated with aspirin-sensitive asthma: should be counseled against
using NSAIDs.
Gastroesophageal reflux, especially nighttime symptoms.
Non-selective β-blockers, including those in ophthalmic preparations, may cause
asthma symptoms: these agents used based on benefit risk assessment.
The ingestion of sulfites can also worsen asthma. These agents are often found in
processed potatoes, shrimp, dried foods, beer, and wines.
Viral infections are the most common cause of increased asthma symptoms and asthma
exacerbations.
New Guideline :Classification of asthma by severity is useful
when decisions are being made about management at the
initial assessment of a patient.
64
65
66
Aerosol Therapy of Asthma
Devices
Factors Determining Lung Disposition of Aerosols (Device and
Patients Determinants)
Patient Education
Devices
 Inhaled medications are preferred (WHY?)
 Inhaled medications for asthma are available as:
 Metered-dose inhaler (MDI)
 pressurized metered-dose inhalers (pMDIs),
 breath-actuated MDIs,
 Dry-powder inhaler (DPI)
 Nebulizers
 jet (mechanically produces a mist of drug)
 ultrasonic (uses sound waves to generate the aerosol)
 Spacer (or valved holding-chamber) devices make inhalers easier to use
and reduce systemic absorption and side effects of inhaled
glucocorticosteroids.
 Must determine which device is best for each patient
An MDI consists of an aerosol canister and
an actuation device (valve). The drug in the
canister is a suspension or solution mixed
with propellant. The valve controls the
delivery of drug and allows the precise
release of a premeasured amount of the
product
A nebulizer is a device that turns asthma
medication into a fine mist that's breathed
in through a mouthpiece or mask worn
over the nose and mouth. A nebulizer is
generally reserved for people who can't
use an inhaler, such as infants, young
children, people who are very ill or people
who need larger doses of medication.
Patient Education
 Appropriate inhalation technique is vital for optimal drug delivery and
therapeutic effect
 up to 30% cannot master MDI technique
 Rinse mouth after inhaled corticosteroids (ICS)
 < 4 years old usually need to attach a face mask to the inhalation device
 For instructions for inhaler and spacer use
 http://www.ginasthma.org/other-resources-instructions-for-inhaler-and-spacer-
use.html
 For educational videos on the use of inhalers , visit
 http://www.nationalasthma.org.au
 http://www.mayoclinic.com/health/asthma/DS00021&tab=multimedia
Take off the cap
and shake the
inhaler hard
Breathe out all
the way
Start breathing in slowly through your
mouth, and then press down on the inhaler
Hold the inhaler 1 to 2
inches in front of your
mouth.
Rinse your mouth
afterward to help reduce