A 36-year-old female with asthma receives continuous aerosolized albuterol; after 1 hour ABG shows PaO2 53 mm Hg; what is the most appropriate action?

• A. Intubate, use (pressure-controlled continuous mandatory ventilation) PC CMV, f = 8
• B. Continue with nebulized therapy
• C. NPPV BiPAP
• D. Increase FiO2 to 1.0

Answer: (A)

When severe asthma leads to marked hypoxemia despite bronchodilator therapy, it means the patient is not able to maintain adequate ventilation and is at risk for respiratory failure. In this situation, securing the airway and providing controlled ventilatory support is the best next step. Endotracheal intubation allows precise oxygenation and ventilation and prevents fatigue from worsening breathing effort.

Using a pressure-controlled continuous mandatory ventilation mode helps in obstructive disease by limiting peak inspiratory pressures, reducing the risk of barotrauma, while still delivering a set tidal volume. A slower rate, such as eight breaths per minute, gives the patient more time to exhale and helps prevent dynamic hyperinflation and auto-PEEP, which are common concerns in severe asthma.

Simply increasing the FiO2 addresses oxygenation only and does not correct the underlying ventilation problem. Noninvasive ventilation could be considered in less severe cases, but with a PaO2 this low and signs of fatigue or failure risk, securing the airway and ventilating is indicated.