PULMONOLOGY Flashcards
How common is allergic rhinitis?
Very common… b/t 10-40% of children experience rhinitis as the most common manifestation of allergic disease
What features on PE suggest chronic allergic rhinitis? (7)
1- congestion
2-“allergic facies” : open mouth, midface hypoplasia
3- “allergic salute”: nasal crease on bridge of nose from chronic upward rubbing of nose with palm
4- diminished sense of taste/smell
5- allergic “shiners” (dark circles under eyes)
6- increased infraorbital folds
7- cobblestoning of conjunctiva/posterior oropharynx
List the major risk factors for allergic rhinitis
1- +FMHx
2- heavy maternal cigarette smoking during first year of life
3- early introduction of solid foods
4- individuals born during pollen season
5- higher serum IgE levels (>100 IU/mL before age 6)
6- atopic dermatitis (eczema)
How does the time of year help identify the potential cause of allergic rhinitis?
- Tree pollen: onset of growing season
- Grass pollen: onset of growing season (after trees)
- Weed pollen: late-summer pollen peak (most common in north/central america = ragweed)
- Fungal: span growing season
- Household animal allergens (dust mites/indoor fungi): increase when windows//doors closed -i.e. colder months, or in areas of high humidity
Which variables affect allergy skin testing? (5)
- Test Site (reactivity order = forearmspecific than> intradermal)
What is RAST? When is it indicated?
“radioallergosorbent test”
=in vitro lab test to quantify the pt’s allergen-specific IgE
(RAST antigen binds to the allergen of interest)
indicated in pts w/ severe skin disorders or risk of severe rxn to skin testing
What are the Pros and Cons of In vitro vs. skin testing for allergies?
In vitro:
- no risk anaphylaxis
- more $$$
Skin testing:
- less $
- more sensitive
- results available immediately
What are the Tx recommendations for children w/ chronic allergic rhinitis?
- change/control environment to avoid allergen
- pharmacotherapy: antihistamines, LTRAs, intranasal steroids, topical cromolyn
- immunotherapy: for pts sub-optimally controlled by 1st 2 measures OR w/ severe sxs
List the major indoor allergens (4)
- dust mites
- mold
- animal dander
- cockroach
How to get rid of cat allergen at home?
- remove upholstered furniture, carpet, etc.
- get new bedding covers + plastic mattress cover
- limit cat’s roaming areas, esp in bdrm
- high efficiency air filter
- ?felinectomy
List the allergy testing methods in order of sensitivity
intradermal > epicutaneous (skin prick) > RAST
What are key questions during Hx taking to Dx allergic rhinitis?
FMHx
Environmental Hx
Assoc Sxs
How to decrease house dust mite levels at home?
- replace mattress and pillow casings (plastic)
- wash bedding q 1-2 wks in hot water
- get rid of stuffed animals, books, and other sources of HDM in bdrm
- dust hard surfaces and vacuum carpets regularly
- reduce indoor humidity (<45%)
When is immunotherapy indicated? When is it contraindicated?
- in some pts to Tx hymenoptera venom sensitivity to prevent life-threatening rxns (bees, wasps, etc)
- for IgE-mediated diseases when avoidance and meds have sub-optimal results
DO NOT give to pt w/ unstable asthma w/ FEV1 <70%
How common is exercise-induced bronchospasm in children w/ allergic rhinitis?
up to 40% of kids with AR (but no asthma) had abN PFTs in response to exercise
At what age do asthma sxs usually present?
50% cases occur before age 3, ~100% before age 7
often sxs are incorrectly attributed to recurrent pneumonia or “wheezing bronchitis”
How many children have wheezing episodes <3 y/o? Of those, how many go on to develop chronic asthma?
1/3
40% develop persistent wheezing
What are the RFs of developing chronic asthma in childhood?
\+FMHx increased IgE levels Atopic dermatitis Allergic Rhinitis (not associated w/ colds) \+second hand smoke exposure
What Hx points are suggestive of an allergic basis for asthma?
- seasonal sxs congruent w/ rhinitis (suggests pollen)
- sxs worse when visiting family w/pets (animal dander)
- wheexing when carpets are vacuumed or bed is made (mites)
- sxs develop in damp basements or barns (molds)
How common is exercise-induced bronchospasm (EIB)?
very common
Significant sxs (cough, CT, SOB, wheeze) noted after exercise in:
- 80% kids w/ asthma
- 40% kids w/ atopy
How is EIB Dx’d?
Peak flow rate of FEV1 drops 15% after 6 min of vigorous exercise (w/ greatest reduction at 5-10 min)
- if found, 2 puffs beta2-agonist should be given to reverse bronchospasm
What is the mechanism that leads to airway obstruction during an acute asthma attack?
What happens in chronic cases?
- airway inflammation (including edema)
- bronchospasm
- increased mucous production
chronic inflammation: leads to remodelling of airways
ALL THAT WHEEZES IS NOT ASTHMA. What are the other noninfectious causes?
- Aspiration pneumonitis
(esp in infant w/ neurological impairment, GERD, sxs of cough/choke/gaging w/feeding…if clear assoc w/ feeding = ?tracheoesophageal fistula) - Bronchiolitis obliterans
(chronic wheezing often after adenoviral infection) - Bronchopulmonary dysplasia
(esp if needed prolonged O2 therapy/vent. as neonate) - Ciliary dyskinesia
(esp if recurrent otits media, sinusitis, or situs inversus present) - Congenital malformations
(ex. trachiobronchial anom’s, trachiomalacial anom’s, lung cysts, mediastinal lesions) - Cystic fibrosis
(if recurrent wheeze, FTT, chronic D, recurr. resp infections) - Congenital cardiac anomalies
(esp right to left shunts) - Foreign-body aspiration
(if assoc w/ acute choking episode in infant <6mo/o) - Vascular rings, slings, or compression
S/S of Mild asthma attack
- PEFR = 70-90%
- Resting Resp rate = N - 30% above mean
- Alertness = N
- Dyspnea = None - mild, speaks full sentences
- Accessory muscle use = None - mild intercostal retractions
- Colour = good
- Auscultation = end exp. wheeze
- O2 sat = >95%
- PCO2 = <35
S/S of Moderate Asthma Attack
- PEFR = 50-70% predicted
- Resting Resp rate = N - 30% above mean
- Alertness = N
- Dyspnea = moderate, speaks in full-partial phrases, infants cry softer + diff feeding/suckling
- Accessory muscle use = moderate (intercostals, tracheosternal, sternocleidomastoid, chest hyperinflation)
- Colour = pale
- Auscultation = constant wheeze
- O2 sat = 90-95%
- PCO2 = <40
S/S of Severe Asthma Attack
- PEFR = <50% predicted
- Resting Resp rate = >50% above mean
- Alertness = ?decreased
- Dyspnea = severe, only single words/short phrases; infants: soft cry, stop feeding/suckling
- Accessory muscle use = severe retractions + nasal flaring + chest hyperinflation
- Colour = ?cyanotic
- Auscultation = decrease/inaudible breath sounds
- O2 sat = <90%
- PCO2 = >40
Should you order CXR in a child w/ first time wheeze?
Only if:
- PE suggest Dx other than asthma
- marked asymmetry of breath sounds
- suspect pneumonia
- suspect foreign-body aspiration
- hypoxemia or marked distress
- older child w/o FMHx of asthma or atopy
- suspect CHF
- Hx trauma (burns, scalds, blunt/penetrating injury)
What are the findings on arterial blood gas (ABG) sampling during an asthma attack?
(most common?)
most common = hypocapnia (low CO2) d/t hyperventilation
hypoxemia (unless pt being treated w/ O2)
What does the finding of hypercapnia on ABGs during an asthma attack a sign of? What should you do?
=serious sign that the child is tiring or becoming severely obstructed
this should prompt reevaluation + consider admission to high-acuity unit
What are indications for hospital admissions for pts w/ asthma?
AFTER therapy in ER, admit if:
- dec’d LOC
- incomplete response w/ moderate retractions, wheezing, peak flow <60%, pulsus paradoxus >15 mmHg, SaO2 <90%, pCO2 >42
- breath sounds significantly diminished
- evidence of dehydration
- pneumothorax (PTX)
- residual sxs + hx of severe attacks involving prolonged hospital stay (esp if was intubated)
- parental unreliability
When is it better to use nebulizers vs. MDIs?
Nebulizers - infants <2yrs
MDIs (+ spacer) - everyone else
List the possible acute SEs of albuterol or other beta2-agonists
- General: hypoxemia, tachyphylaxis
- Renal: hypokalemia
- CV: tachy, palpitations, PVCs, Afib
- Neuro: HA, irritability, insomnia, tremor, weakness
- GI: N, heartburn, V
