Asthma (Various PDFs, Harrison 254) Flashcards
Asthma “severity”
intrinsic intensity of the disease process
Asthma “control”
degree to which the manifestations of asthma are minimized by therapeutic intervention (goals of therapy met)
Asthma “impairment”
Frequency & intensity of symptoms & limitations patient is experiencing or recently has experienced
One of the 2 key domains of asthma control, along with risk.
Asthma “risk”
Likelihood of either asthma exacerbation, decline in lung function (or lung growth in kids), or risk of adverse medication effects
Jeopardy Style! Asthma for $200…
Inhaled corticosteroids (ICS)
What is the preferred long-term asthma control therapy for all ages, Alex?
Jeopardy Style! Asthma for $300…
Combination of long-acting beta2-agonists (LABA) and ICS
An equally preferred asthma control option, with increasing the dose of ICS in patients ≥ 5 years old.
This balances the benefits of combo therapy with the risk for increased exacerbations associated with LABA.
What is a risk of LABA that we should keep in mind?
Increased risk of severe asthma exacerbations
Jeopardy Style! Asthma for $400…
Omalizumab
Recommended for consideration in youths ≥12 years old who have allergies, or for adults who require step 5 or 6 care (severe asthma)
What does FEV1 stand for?
Forced expiratory volume in 1 second
What does PEF stand for?
Peak expiratory flow
What FEV1/PEF percentage indicates severe exacerbation in the urgent/emergency setting?
< 40%
What FEV1/PEF percentage is the goal for discharge of an asthma exacerbation patient?
> 70%
Goals of long-term asthma management
1) Reduce impairment: prevent chronic symptoms, require infrequent use of short-acting beta2 agonist (SABA), maintain at or near normal lung function & normal activity levels
2) Reduce risk: prevent exacerbations, minimize need for emergency care or hospitalization, prevent loss of lung function or prevent reduced lung growth in children, have minimal or no adverse effect of therapy
Stepwise approach to asthma: general principles for all age groups
1) Incorporate 4 components of care (meds, patient education, environmental control measures, & mgmt of comorbidities at each step)
2) Initiate therapy based on asthma severity
3) Adjust therapy based on asthma control
Key activities for asthma control in ages 12 & older
1) Involve youths in developing written asthma action plan
2) Promote physical activity
3) Assess benefit of treatment in older patients
4) Adjust meds to address coexisting medical conditions common in older patients
Treatment strategies to prevent EIB include…
1) long term control therapy
2) Pretreatment before exercise with SABA, leukotriene receptor antagonists (LTRA), frequent or chronic use of LABA for pretreatment is discouraged, as it may disguise poorly controlled persistent asthma
3) Warmup period or a mask/scarf over mouth for cold-induced EIB
How can we reduce risk of complications during & after surgery?
Before: If lung function not well-controlled, meds to improve it. Short course of oral systemic corticosteroids may be necessary.
After: For patients with oral steroids during 6 months prior to surg, & for select patients on high dose ICS, give 100 mg hydrocortisone every 8 hrs during surgical period & reduce dose rapidly within 24 hrs post-surgery
Patient education for home asthma management
Instruct patient how to:
1) Recognize early signs, symptoms, PEF measures that indicate worsening
2) Adjust meds & remove or withdraw from environmental factors contributing to exacerbation
3) Monitor response & seek medical care for serious exacerbation or lack of response to treatment
Asthma Mgm’t in Urgent/Emergency Care: Key Points
1) Assess intital severity by lung function measures, symptom & functional assessment
2) Supplemental O2
3) Repetitive or continuous SABA
4) Oral systemic steroids
5) Monitoring response with serial lung function measures, pulse ox, and symptoms
6) Consider adjunctive treatments (magnesium sulfate or heliox) for severe exacerbations unresponsive to initial treatment
7) At discharge: meds, referral to follow up, ED asthma discharge plan, review of inhaler technique & environmental control measures
Key symptoms for asthma diagnosis:
1) Wheezing, esp in children. Lack of wheezing & normal chest exam do not exclude asthma.
2) History of any of following: cough (particularly worse at night), recurrent wheeze, recurrent difficulty breathing, recurrent chest tightness
3) Symptoms occur or worsen in presence of: exercise, viral infection, inhalant allergens, irritants, weather changes, strong emotional expression (laughing or crying), stress, menstrual cycles
4) Symptoms occur or worsen at night, awakening patient
What is important to remember about the physical exam in asthma?
Some findings increase probability of asthma, but their absence doesn’t rule it out. Asthma is variable & many signs may be absent between episodes.
What are some physical exam findings that increase the probability of asthma?
Upper resp tract: increased nasal secretion, mucosal swelling, nasal polyps
Chest: sound of wheezing during normal breathing, prolonged forced exhalation, hyperexpansion of thorax, accessory muscle use, hunched shoulders, chest deformity
Skin: eczema, atopic dermatitis
Differential Diagnosis for Asthma in Adults
1) COPD
2) CHF
3) PE
4) Mechanical obstruction of airways (benign or malignant tumors)
5) Pulmonary infiltration with eosinophilia
6) Cough secondary to drugs (ACEi)
7) Vocal cord dysfunction
Cough variant asthma
Cough can be the principal, or ONLY, manifestation of asthma, esp in children
Vocal cord dysfunction (VCD) can be differentiated from asthma in what way?
It response little–if at all–to asthma medications.
What are some comorbidities that may complicate asthma diagnosis?
GERD, sleep apnea (OSA), and allergic bronchopulmonary aspergillosis (ABPA)
What is meant by “stepwise” approach to asthma?
Therapy is increased (step up) or decreased (step down) as needed to achieve control with minimal meds.
Monitoring & follow-up are essential, bc asthma is variable & may need to be stepped up or down to maintain control.
Stepwise Asthma Control: Step 1 of 6
Preferred: SABA PRN
Stepwise Asthma Control: Step 2 of 6
Preferred: Low-dose ICS
Alt: Cromolyn, LTRA, nedocromil, or theophylline
Stepwise Asthma Control: Step 3 of 6
Preferred: Low-dose ICS + LABA, OR med-dose ICS
Alt: Low-dose ICS+ either LTRA, theophylline, or zileuton
Stepwise Asthma Control: Step 4 of 6
Preferred: Med-dose ICS+LABA
Alt: Med-dose ICS + either LTRA, theophylline, zileuton
Stepwise Asthma Control: Step 5 of 6
Preferred: High-dose ICS+LABA & ALSO consider omalizumab for patients who have allergies
Stepwise Asthma Control: Step 6 of 6
Preferred: High-dose ICS+LABA+oral steroid & ALSO consider omalizumab for patients who have allergies
Severity of asthma exacerbation in urgent/emergent setting: Mild
Dyspnea: only with activity
PEF: ≥ 70% predicted or personal best
Clinical course: usually cared for at home, prompt relief with inhaled SABA, possible short course of oral steroids
Severity of asthma exacerbation in urgent/emergent setting:
Moderate
Dyspnea: Interferes with or limits activity
PEF: 40-69% predicted or personal best
Clinical course: Usually requires office or ED visit; relief from frequently inhaled SABA; oral steroids; some symptoms last 1-2 days after treatment begun
Severity of asthma exacerbation in urgent/emergent setting:
Severe
Dyspnea: at rest; interferes with conversation
PEF: ≤ 40% predicted or personal best
Clinical course: Usually requires ED visit, maybe hospitalization; partial relief from frequent inhaled SABA; oral steroids; some symptoms last > 3 days after treatment begun; adjunctive therapies helpful
Severity of asthma exacerbation in urgent/emergent setting:
Life threatening
Dyspnea: too dyspneic to speak; perspiring
PEF: < 25% predicted or personal best
Clinical course: requires hospitalization, possible ICU; minimal or no relief from SABA; IV steroids; adjunctive therapies helpful
For an adult with asthma exacerbation, what is the strongest single predictor of hospitalization?
Repeated FEV1/PEF at 1 hour & beyond. May not be easily obtained during severe exacerbation.
Signs & symptoms scores at 1 hour after beginning treatment improve ability to predict hospitalization.
What is asthma?
Syndrome of airflow obstruction that varies markedly, both spontaneously & with treatment.
Rates of asthma have risen along with…
…urbanization, especially in affluent countries.
What is the major risk factor for asthma?
Atopy!
What other atopic diseases might be found in an asthma patient?
1) Allergic rhinitis
2) Atopic dermatitis (eczema)
What is intrinsic asthma?
Asthma found in non-atopic patients (negative allergen skin tests, normal serum IgE). Commonly more severe, persistent asthma.
Commonly adult-onset, concomitant nasal polyps, may be aspirin sensitive.
Characteristic symptoms of asthma
Wheezing
Dyspnea
Coughing
How does time of day affect asthma symptoms?
Patients may be worse at night & report waking in early morning hours
What kind of prodromal symptoms may precede an exacerbation?
1) Itching under chin
2) Discomfort btwn scapulae
3) Sense of impending DOOOOOOOOM (it has that in common with this exam…)
Typical physical signs of asthma
1) Rhonchi throughout chest (typically expiratory greater than inspiratory)
2) Possible hyperinflation
3) Non-productive cough (cough-variant asthma may have ONLY this sign)
How is a lung function test used to diagnose asthma?
Spirometry confirms airflow limitation with reduced FEV1, FEV1/FVC ration, and PEF.
Short-acting beta2-agonists (SABA): what are they used for? How short is “short”?
Immediate exacerbation control. Rapid onset, duration of 3-6 hours.
Frequent use of these indicates poor underlying control.
SABA side effects
Not usually problematic with inhaled. Most common: muscle tremor & palpitations.
Why should LABA never be given without ICS?
LABA do not control the underlying inflammation that causes airway constriction in the first place.
How do LABA improve control when added to ICS?
Improve control & reduce exacerbations, allowing asthma to be controlled at lower steroid doses.
How are anticholinergics useful in asthma?
They are used for bronchoconstriction, but they are LESS EFFECTIVE & SLOWER than SABA. They should be used only in addition to and after SABA administration.
How is theophylline useful in asthma?
It was widely prescribed years ago (it was cheap) but due to side effects & more effective beta2-agonists, it’s fallen out of favor.
It can be used in low doses, daily or BID, in addition to ICS.
Theophylline: side effects
Due to phosphodiesterase inhibition: Nausea/vomiting; Headaches; palpitations; diuresis
Toxicity is possible! Signs: cardiac arrhythmias, seizures, death
Also: metabolized by CYP450, so plasma levels are elevated by drugs that block this enzyme system
The number one most effective controller for asthma:
Inhaled corticosteroids (ICS)!
“Their early use has revolutionized asthma therapy” according to Harrison’s.
Benefits of ICS in asthma
1) Rapidly improve symptoms
2) Improve lung function in several days
3) Prevent symptoms like EIA & nocturnal exacerbation
4) Prevent severe exacerbations
5) Prevent irreversible airway remodeling
Inhaled steroids are preferred over oral because…
…the inhalation route reduces systemic absorption, & therefore steroid side effects.
When systemic steroids are used, is it more effective to do IV or PO?
We usually do IV, but several studies now show that PO is just as effective but easier to administer.
What is the systemic steroid course like when treating an acute asthma exacerbation?
Prednisone or prednisolone 30-45 mg daily for 5-10 days; no tapering is needed.
Approximately 1% of asthma patients may require:
maintenance treatment with oral steroids.
What are the potential side effects with long-term systemic steroid treatment?
Truncal obesity Bruising Osteoporosis Diabetes HTN Gastric ulcers Proximal myopathy Depression Cataracts
How do anti-leukotrienes benefit asthma patients?
They block cys-LT1 receptors, which produce inflammation when activated. They are less effective than ICS, but they can be a helpful add-on therapy.
What are the 2 major patterns of difficult-to-manage asthma?
1) Persistent symptoms & poor lung function despite maximum inhaled therapy
2) Normal or near-normal lung function but intermittent, severe, possibly life-threatening exacerbations.
