What are the exact step‑by‑step management steps for treating status asthmaticus in an adult?

Step-by-Step Management of Status Asthmaticus in Adults

Administer oral prednisone 40–60 mg immediately upon recognition of status asthmaticus, along with continuous nebulized albuterol and high-flow oxygen to maintain SpO₂ >92%. 1

Immediate Assessment (First 5 Minutes)

• Measure oxygen saturation and initiate supplemental oxygen at 40–60% via face mask to maintain SpO₂ >92%. 2, 3
• Obtain peak expiratory flow (PEF) or FEV₁ measurement—never rely on clinical impression alone, as failure to objectively measure severity is a documented cause of preventable asthma deaths. 2, 1
• Assess for life-threatening features: PEF <33% predicted, silent chest, confusion, exhaustion, inability to complete sentences, respiratory rate >25/min, or pulse >110/min. 1

First-Line Therapy (Initiate Within 15 Minutes)

Systemic Corticosteroids – Highest Priority

• Give oral prednisone 40–60 mg immediately as a single dose—do not wait for bronchodilator response, as the anti-inflammatory effect requires 6–12 hours to manifest and delaying steroids is a leading preventable cause of asthma death. 1
• Oral administration is equally effective as intravenous therapy and is strongly preferred when the patient can swallow. 2, 1
• Reserve IV hydrocortisone 200 mg (then 200 mg every 6 hours) only for patients who are vomiting, severely ill, or unable to tolerate oral intake. 2, 1, 3

Inhaled Beta-Agonists

• Deliver albuterol 2.5–5 mg via oxygen-driven nebulizer every 20 minutes for three doses, then reassess. 1, 4
• Alternatively, use metered-dose inhaler with large-volume spacer (4–8 puffs every 20 minutes) if nebulizer unavailable—this method produces equivalent bronchodilation with fewer side effects in severe obstruction. 5
• Measure PEF 15–30 minutes after initial bronchodilator dose to gauge response. 2, 1

Add Ipratropium Bromide

• Add ipratropium 0.5 mg to the nebulizer with albuterol if the patient shows poor response after 15–30 minutes or has severe features at presentation. 2, 1
• Repeat ipratropium every 6 hours in severe cases. 1

Reassessment at 60–90 Minutes

• Remeasure PEF and oxygen saturation. 1
• If PEF remains <50% predicted or patient shows signs of respiratory muscle fatigue (paradoxical breathing, decreased air entry, altered mental status), escalate to second-line therapies. 2, 6

Second-Line Therapies (For Inadequate Response)

Intravenous Magnesium Sulfate

• Administer magnesium sulfate 2 g IV over 20 minutes for severe exacerbations not responding to conventional therapy within the first hour. 7, 4

Continuous Nebulized Albuterol

• Switch to continuous nebulization at 10–15 mg/hour if intermittent dosing fails, though evidence does not strongly favor this over high-dose intermittent therapy. 5

Consider Subcutaneous Beta-Agonists

• Give terbutaline 0.25 mg subcutaneously (may repeat every 20 minutes × 3 doses) for patients with poor air entry, uncooperative with nebulized therapy, or inadequate response. 7

Indications for Mechanical Ventilation

• Severe exhaustion, deteriorating consciousness, worsening hypoxemia despite maximal therapy, progressive hypercapnia, or cardiopulmonary arrest mandate intubation. 6, 7
• Use controlled hypoventilation strategy: limit minute ventilation, prolong expiratory time, accept permissive hypercapnia to avoid ventilator-induced lung injury. 6
• Avoid paralytic agents unless respiratory function is extremely unstable, as they increase risk of ICU myopathy. 6

Corticosteroid Continuation and Duration

• Continue prednisone 40–60 mg daily until PEF reaches ≥70% of predicted or personal best, typically 5–10 days. 1
• No tapering is required for courses <7–10 days, especially if the patient is on inhaled corticosteroids—tapering may lead to underdosing during recovery. 2, 1
• Higher doses (>60 mg/day) provide no additional benefit but increase adverse effects. 1

Concurrent Controller Therapy

• Initiate or increase inhaled corticosteroid dose to at least 800 µg/day beclomethasone-equivalent at least 48 hours before discharge. 2, 1
• Continue short-acting beta-agonist as needed, but if used >2–3 times daily after stabilization, step up controller therapy. 2

Discharge Criteria

• PEF >75% of predicted with diurnal variability <25%. 1
• Patient stable on discharge medications for ≥24 hours. 1
• Nocturnal symptoms resolved. 1
• Patient demonstrates correct inhaler technique and possesses a written asthma action plan. 1
• Peak flow meter prescribed with clear instructions on when to escalate treatment or seek urgent care. 1

Follow-Up

• Schedule primary care follow-up within 1 week and respiratory specialist appointment within 4 weeks. 1, 3
• Patients who required mechanical ventilation have 14% mortality at 3 years and require very close medical follow-up. 6

Critical Pitfalls to Avoid

• Never delay systemic corticosteroids while giving repeated bronchodilators alone—underuse of steroids is the most common preventable factor in asthma deaths. 1
• Never use sedatives in acute asthma—they are contraindicated and potentially fatal. 1
• Do not underdose steroids: the minimum effective range is 40–60 mg prednisone daily, not 30 mg. 1
• Do not discharge patients before achieving objective improvement in PEF—clinical impression alone is unreliable. 2, 1