Asthma Exacerbation

# Asthma Exacerbation
Increased frequency of SABA, using MDI [＞2x per week], increased dyspnea, night awakenings, limited normal activity. Most recent spirometry was [date]. Number of ED visits in the past year that required oral steroids [#].
DDx: laryngeal / tracheal dysfunction, narrow supraglottic airway, foreign body aspiration, airway edema, chronic bronchitis or emphysema, bronchiectasis, allergic bronchopulmonary mycosis, cystic fibrosis, eosinophilic pneumonia, hypersensitivity pneumonitis, sarcoidosis, and bronchiolitis obliterans, eosinophilic granulomatosis with polyangitis, heart failure and pulmonary hypertension, conversion disorder.
- SpO2 ＞95% on 5L nasal cannula
- peak expiratory flow (PEF), normally 450-650 L/min in men and 350-500 L/min in women.
Mild severity, PEF ＞300L/min, HR＜100, SaO2＞95, speaks in sentences, can lie down, not using accessory muscles
Moderate, 100-300L/min, RR＞20, HR＞100, SaO2＞90, FEV1 40-69%, speaks in phrases, Pulsus paradoxus ＞10mmgHg drop in BP blood pressure during inspiration
Severe: PEF ＜100L/min, RR＞30, HR＞120, SaO2＜90, speaks in words, sits upright, Pulsus paradoxus ＞20mmgHg drop in BP blood pressure during inspiration
- CXR
Tx:
if mild:
-SABA by MDI, q20min in first hour or Neb 0.15 mg/kg with a max dose of 5 mg.
- predisone PO 0.5-1.0 mg/kg/day), prednisolone 40-50mg, children 1-2mg/kg
-consider ipratropium (IB), 17 mcg/puff, 2-3 puffs q6h
-if good response SABA q4h 7 days, oral steroid 7 days, continue controller meds, consider ICS
if moderate:
- continuous SABA and ipratropium bromide (IB) by neb, oral corticosteroids, then SABA q40min
if severe:
- continuous SABA, IB, consider heliox, epinephrine IM, 2g Mg sulfate IV over 20min

Admit if...
ARDS, Decreased level of consciousness, Hypoxia: ＜93%, Hypercapnea: CO2 ＞42, Dehydration, Peak flow ＜50% predicted, pulsus paradoxus ＞15mmHg, need for IV SABA, mechanical vent
Underlying high risk factors: heart disease, neuromuscular disease, cystic fibrosis, bronchopulmonary dysplasia, history of ICU admission, unreliable parents or care givers, long distance from the ER.
ER visit within the preceding 24 hours.

D/c
Provide written action plan
Train for self-monitoring (peak flows), Educate and reinforce correct inhaler techniques, Refer to an asthma education program
Schedule follow-up
Consider home environment (tobacco exposure, allergen avoidance, social support)

Step down therapy is considered after at least 3 months of being well-controlled