This document provides an overview of asthma including its definition, epidemiology, risk factors, pathogenesis, clinical features, diagnosis, status asthmaticus, and treatment. Asthma is a heterogeneous disease characterized by airway inflammation and affects approximately 300 million people worldwide. Key risk factors include atopy, genetic predisposition, infections, obesity, and air pollution. Clinical features include symptoms of wheezing, coughing, and shortness of breath. Diagnosis involves assessing symptoms and lung function tests. Treatment involves inhaled corticosteroids and bronchodilators, with status asthmaticus defined as an acute exacerbation not responding to standard treatment and requiring more intensive interventions.

1. Presentor: Hosanna W Asfaw

2.  Asthma definition
 Epidemiology
 Risk factors
 Pathogenesis
 Clinical features
 Diagnosis
 Status asthmaticus
 Treatment

3.  “a heterogeneous disease, usually
characterized by airway inflammation. It is
defined by the presence of respiratory
symptoms such as wheeze, shortness of
breath, chest tightness and cough that vary
over time and in intensity, together with
variable expiratory airflow limitation.”

4.  affects approximately 300 million people
worldwide (Harrisons 19E)
 can present at any age, with a peak age of 3
years.
 In childhood, M:F ration is 2: 1
 By adulthood the sex ratio has equalized

5. Airway
hyperesponsiveness
Airway inflammation
Reversible airway
obstruction

7.  Atopy
 allergic rhinitis (80%)
 atopic dermatitis (eczema)
 Genetic predisposition
 Determines severity, is polygenic
 Novel genes: ADAM-33, and DPP-10
 Infections
 Atypical bacteria, such as Mycoplasma and
Chlamydophila

8.  Obesity
 BMI> 30 kg/m2
 more difficult to control
 Others
 Air pollution
 Cold air
 In utero exposure to environmental tobacco
smoke
 Pharmacologic agents (ẞ blockers)

10. GINA

11.  >1 sx (wheeze, shortness of breath, cough,
chest tightness)
 Symptoms often worse at night or in the
early morning
 Symptoms vary over time and in intensity
 Symptoms are triggered by viral infections
(colds), exercise, allergen exposure, changes
in weather, laughter, or irritants

12.  Isolated cough
 Chronic production of sputum
 SOB associated with dizziness, light-
headedness or peripheral tingling (paresthesia)
 Chest pain
 Exercise-induced dyspnea with noisy
inspiration.

16.  Allergic asthma:
 starts in past and/or family history of allergic disease such
as eczema, allergic rhinitis, or food or drug allergy.
 Examination of the induced sputum reveals eosinophilic
airway inflammation
 Respond well (ICS) treatment.
 Non-allergic asthma:
 Sputum neutrophilic, eosinophilic or contain only a few
inflammatory cells
 Respond less well to ICS.

17.  Late-onset asthma
 particularly women
 non-allergic
 require higher doses of ICS or are refractory to corticosteroid
treatment.
 Asthma with fixed airflow limitation:
 some patients with long-standing asthma develop fixed airflow
limitation that is thought to be due to airway wall remodeling.
 Asthma with obesity:
 obese patients have prominent respiratory symptoms
 little eosinophilic airway inflammation.

19. • classically present with a history of episodes of coughing,
chest tightness, shortness of breath, and wheezing
 onset of symptoms with specific triggers
 Family history
 Social history
 home characteristics, smoking, workplace or
school characteristics, educational level, social
support, non-adherence of asthma medications,
and illicit drug use.

20.  Prodromal symptoms may precede an attack
 Itching under the chin
 discomfort b/n scapula
 unexplained fear.

21.  Hyperexpansion of the thorax
 Wheezing during normal breathing
 Prolonged phase of forced exhalation
 Increased nasal secretion, mucosal swelling,
and/or nasal polyps
 Atopic dermatitis/eczema

22.  Lung function tests
Spirometry
▪  forced expiratory volume in 1 second (FEV1)
▪ FEV1/FVC <0.7 generally defines obstruction.
▪ peak expiratory flow (PEF)
▪ Reversibility
▪ increase in FEV1 of ≥12% or >200 mL after inhalation of a short-
acting bronchodilator
Flow volume loop

24.  Provocation studies airway hyperresponsiveness
 Metacholine/ histamine challenge
 A 20 % reduction in FEV1
 Exhaled NO – to measure air way inflammation
 Total serum IgE and specific IgE to inhaled allergens
 Skin prick test to common inhalant allergens

25.  Airway Hyperresponsiveness
Methacholine or histamine challenge
 Laboratory tests: not usually helpful
Blood eosinophilia
Sputum eosinophilia
Serum IgE levels
 Chest X-ray: usually normal, may show hyperinflated lungs
 Exhaled nitric oxide (FENO)
 Allergy skin testing

26.  Upper airway obstruction
flow-volume loop
 Endobronchial obstruction
 Vocal cord dysfunction
 COPD
 Congestive heart failure
 Pulmonary embolism
 Pulmonary infiltration with eosinophilia
 Cough secondary to drugs (e.g.,ACE
inhibitors)

27. Condition Characteristics
COPD Airway obstruction is less reversible; typically seen in older patients
with smoking history
Vocal cord
dysfunction
Abrupt onset and end of symptoms; monophonic wheeze; more
common in younger patients; confirm with laryngoscopy or flow-
volume loop
Heart failure Dyspnea and often wheezing; crackles on auscultation; limited
response to asthma therapy; cardiomegaly; edema
Bronchiectasis Cough productive of large amount of purulent sputum; rhonchi and
crackles are common; may have wheezing and clubbing; confirmed by
CT imaging
ABPA Recurrent infiltrates on chest radiograph; eosinophilia; positive skin
testing to Aspergillus antigens, high IgE levels
Mechanical
obstruction
More localized wheezing; if central in location, flow-volume loop may
provide a clue
Eosinophilic
granulomatosis
with polyangiitis
Autoimmune small-vessel vasculitis presents with peripheral
eosinophilia, lung symptoms similar to asthma

31. ẞ2-Agonists
 Relax airway smooth-muscle cells
 No effects on inflammatory cells
 SABAs: 3–6 h
Salbutamole- useful in preventing EIA if taken prior to
exercise
 LABAs: >12h
salmeterol and formoterol (Important to use ICS when LABAs
are given
Anticholinergics
prevent cholinergic nerve-induced bronchoconstriction and
mucus secretion. once- daily tiotropium bromide
Theophylline- Side Effects

32. Inhaled corticosteroids (ICSs)
 Most effective controllers for asthma
 Anti-inflammatory
 ↑expression of β2-receptors
 Reduce AHR
 First-line therapy for patients with persistent asthma
 Local side effects
 hoarseness (dysphonia)
 oral candidiasis
Antileukotrienes, Cromones, Anti-IgE

33. Intermittent Persistent
Components of
Severity
Mild Moderate Severe
Symptoms ≤2 days/week >2 days/week but
not daily
Daily Throughout the day
Nighttime
awakenings
≤2 ×/month 3-4 ×/month >1 ×/week but not
nightly
Often 7 ×/week
SABA use for
symptom control
≤2 days/week >2 days/week but
not more than 1
×/d
Daily Several times a day
Lung function FEV1 ≥80% of
predicted
FEV1/FVC normal
FEV1 ≥80% of
predicted
FEV1/FVC normal
FEV1 ≥60% but
<80% of predicted
FEV1 <60% of
predicted
Exacerbations 0-1/year >2/year >2/year >2/year

35. Also known as STATUS ASTHMATICUS

36.  Formerly known as status asthmaticus
 Acute exacerbation of asthma that does not
respond to standard treatment
(Bronchodilators, inhalers, steroids)
 Medical emergency

37.  50% due to URTIs
 Non adherence
 NSAID exposure in ASA-allergic patients
 Allergen exposure
 Irritant inhalation

38.  Chest tightness, wheezing, use of accessory
muscles and dyspnea that are often not or
poorly relieved by their usual reliever inhaler
 breathless that they are unable to complete
sentences
 cyanotic

39.  General appearance:
alteration of consciousness
 fatigue
upright posture
 diaphoresis
 Respiratory system
 tachypnea (>30min)
 use of accessory muscles for breathing
 reduced respiratory excursion
 diffuse expiratory wheezing
 Cyanotic

40.  Cardiovascular system
 Tachycardia (>120/min)
 pulsus paradoxus
 SPIROMETRY
 PEFR< 120L/MIN
 FEV1< 1L
 Arterial blood gas analysis
 hypercapnia or normal
 CXR:
 over inflated lung

41.  Cardiac arrest
 Respiratory failure or arrest
 Hypoxemia with hypoxic ischemic central
nervous system (CNS) injury
 Pneumothorax or pneumomediastinum
 Toxicity from medications

42.  Good prognosis if appropriate therapy is administered.
 …unless a complicating illness such as
 CHF
 COPDis present
 A delay in initiating treatment is probably the worst
prognostic factor

44.  High concentration of oxygen + High doses of SABA
 Severely ill patients with impending respiratory failure, IV
β2-agonists
 Nebulized anticholinergic- if unsatisfactory response to
β2-agonists
 patients who are refractory to inhaled therapies, a slow
infusion of aminophylline
 Magnesium sulfate given intravenously or by nebulizer
with inhaled β2-agonists
 Prophylactic intubation for impending respiratory failure,
when the PCO2 is normal or rises.
 Patients with respiratory failure necessary to intubate

45.  These patients may benefit from an
anesthetic such as halothane if they have not
responded to conventional bronchodilators.
 Sedatives are C/I  depress ventilation.
 Antibiotics not required unless there are signs
of pneumonia.

46. Thank you for your
attention

47.  Harrison’s principles of internal medicine 19th
e/o
 Global asthma initiative for asthma
 Review article Chapter 14: Acute severe
asthma(status asthmaticus)
 Review article [Status asthmaticus]