FCEM2-1830

You are managing a young woman in the Emergency Department who is feeling unwell. She informs you that she has a history of bronchial asthma and has suddenly developed difficulty breathing since this morning. You can hear wheezing when you listen to her chest, and her peripheral oxygen saturation remains low despite receiving nebulized salbutamol. After a few minutes, she starts to become more drowsy. You recently completed your Advanced Life Support (ALS) training and feel confident in managing acutely unwell patients.

What is the most appropriate initial step to take in this situation?