II. Pathophysiology
- See Asthma
III. History: Initial
-
General: History is not always accurate
- Confirm with Pulmonary Function Tests every 3-6 month
- Patient may underplay symptoms
- Symptom accommodators (10% of patients)
- Do not recognize severe Symptoms of their Asthma
- Age of onset and Asthma diagnosis
- Past history of Respiratory Failure or Intubation
- Recognize cohorts at additional risk
- Elderly
- Pregnancy
- History of early life injury to airways
- Bronchopulmonary Dysplasia
- Parental smoking
- Disease progression
- Present management and response
- Frequency of Systemic Corticosteroid use
- History steroid-induced complications
- Comorbid conditions and potential triggers
- Exercise Induced Bronchospasm
- Aspirin and NSAID allergy
- Allergic Rhinitis
- Chronic Sinusitis
- Assess in all Asthma patients
- Consider empiric treatment if refractory Asthma
- Tsao (2003) Chest 123:757-64 [PubMed]
- Family History
- Social History
- Home characteristics
- Heating and cooling system
- Wood burning stove
- Humidifier
- Carpeting over concrete
- Smokers in home
- Daycare and school situation impacting compliance
- Level of education of patient and parents (if child)
- Home characteristics
- Effects of Asthma
- Episodes of unscheduled care (Emergency Department)
- Life threatening exacerbations
- Number of missed school days
- Limitation of activity
- History of nocturnal awakenings
- Impact of family routines and finances
IV. History: Follow-up Asthma control questions (last month)
V. Symptoms: Episodic
- Recurrent Wheezing
- Dyspnea
- Productive or Paroxysmal cough (especially at night)
- Chest tightness
- Provocative factors
- Exercise
- Viral Infection
- Animals with fur or feathers
- House-Dust mites
- Mold
- Smoke (Tobacco, wood)
- Airborne irritants (Pollen, chemicals, dusts)
- Weather changes
- Emotional stress
- Menses
VI. Signs: General
- Expiratory Rhonchi
- High pitched sounds
- Air moving through constricted and inflamed airway
-
Wheezing may or may not be heard
- Provocative measures
- Maximal expiration quickly
- Apply pressure anterior and superior
- Provocative measures
- Prolonged Inspiratory to Expiratory ratio
- Hyperexpansion of thorax and accessory Muscle use
- Diminished chest excursion
- Place one hand on anterior chest
- Place the other hand posteriorly
- Nasal mucosal swelling or Nasal Polyps
- Atopic Dermatitis, Eczema, Urticaria
VII. Signs: Respiratory distress
- Tachypnea
- Dyspnea
- Anxiety
- Accessory Muscle Use
- Cyanosis in severe cases (lips)
- Tachycardia
- Pulsus Paradoxus
VIII. Imaging: Chest XRay
IX. Diagnosis
- Age 5 years old or over
- Symptomatic episodes of airflow obstruction or hyperresponsiveness (see below)
- Alternatives on differential diagnosis excluded (see below)
- Partially reversible airflow obstruction
- Peak Expiratory Flow >20% variation over 2 weeks
- FEV1 and FEV1/FVC ratio reduced
- FEV1 improves >12% or 200 ml after Bronchodilator
X. Differential Diagnosis
XI. Labs
-
Arterial Blood Gas (ABG)
- Hypoxemia
- Hypercarbia (or normal CO2) with decompensation
-
Complete Blood Count
- Eosinophilia may be present
- Increased Levels of IgE may be present
-
Sputum Sample
- May show casts of small airways
- Thick mucoid Sputum
- Curschmann's spirals
- Charcot-Leyden crystals
-
Pulmonary Function Tests display Obstructive pattern
- See Diagnosis above
XII. Management
- See Asthma Management
- See Asthma Exacerbation
XIII. References
- (1997) Practical Guide for Asthma, NIH 97-4053
- Serrano (2014) Crit Dec Emerg Med 28(6):2-10
- Wojtczak (1999) Guidelines for Pediatric Asthma Lecture
- Evans (1992) Chest 101(6 suppl):368S-71S [PubMed]
- Falk (2016) Am Fam Physician 94(6): 454-62 [PubMed]
- Kemp (2001) Am Fam Physician 63(7):1341-54 [PubMed]
- Moffitt (1994) Am Fam Physician 50(5): 1039-50 [PubMed]
- Shutari (1995) Am Fam Physician 52(8): 2225-35 [PubMed]
- (1996) MMWR Morb Mortal Wkly Rep 45:350-3 [PubMed]