Evaluating response to care

Following treatment, score severity of symptoms again:

• Full response: PEF/FEV1 over 70% and symptomatic improvement at 1-3 hours: consider discharge
• Partial response: PEF/FEV1 of 40-69% and some symptomatic improvement at 4 hours
• Inadequate response: PEF/FEV1 of under 40% and minimal symptomatic improvement at 4 hours: admission without advanced airway
• No response: PEF/FEV1 of under 25% and no symptomatic improvement at 4 hours: admission and advanced airway.  

Full Response

This refers to the patient whose PEF or FEV1 is 70% or higher, is breathing room air with an oxygen saturation of 95% or more and is clinically feeling improved following standard therapy (inhaled beta 2 agonist, corticosteroids and anticholinergic). These patients may be discharged home. They do need good follow-up and identification of any possible risks for recurrence. 

• Ensure stability for at least one hour following full response (i.e., one hour after FEVE reaches 70% or higher)
• Ensure compliance with the home medication regimen. Patients should be given inhaled beta 2 agonists and oral or inhaled corticosteroids at discharge to reduce the risk of return to the ED. 

Partial Response

This refers to the patient whose PEF or FEV1 is between 40-69%, has an oxygen saturation between 90-95%, but still has symptoms of moderate or severe asthma following treatment over 4 hours. More evaluation is needed to determine disposition. Consider any significant comorbidities (i.e., insulin-dependent diabetes, COPD, CAD, and pneumonia).

Low-risk patients: these patients are candidates for discharge. They will need good follow-up, detailed home medication instructions, and adequate resources at home. 

High-risk patients: a finding of a high-risk factor suggests the benefit of admission:

• Prior history requiring advance airway and ventilatory assistance for asthma
• Hospitalization within 1 month for asthma
• Recent ED visit in the past 24-48 hours for asthma
• Attack episode lasting one week or more
• Baseline using oral steroids
• Lack of home resources
• Poor ability to comply with the treatment plan

Inadequate response 

This refers to the patient whose PEF or FEV1 is between 25-40% and still has symptoms of moderate or severe asthma following treatment over 4 hours. These patients require admission with close monitoring and prolonged bronchodilation. The addition of noninvasive positive pressure ventilations (NIPPV) is useful in these cases to diminish the need for intubation. 

No response

This refers to the patient whose PEF or FEV1 is under 25% and has no resolution of symptoms of asthma following treatment over 4 hours. These patients require admission to intensive care and likely advanced airway management with mechanical ventilation. The determination to admit to the ICU is based on certain clinical factors

• PO₂ under 65 mm Hg using 40% FiO₂ (SpO₂ is under 90%)
• PaCO₂ over 40 mm Hg or rising
• Altered consciousness
• Continued breathlessness
• Unable to lay flat
• Progressive fatigue