A 65-year-old woman presents to your office for evaluation of facial swelling that started this morning and is progressively worsening.

A 65-year-old woman presents to your office for evaluation of facial swelling that started this morning and is progressively worsening. On exam, you note swelling to her upper and lower lips, tongue, and her right eye. You also note generalized urticaria on her trunk. She currently has not had any difficulty breathing or swallowing. She has a medical history including hypertension and her last dose of lisinopril was taken this morning around 6 AM. You recognize the urgency of the condition and dispatch emergency services for transport to the emergency department. Which of the following is the first priority in caring for this patient while you wait for emergency services? Administer intravenous epinephrine Administer oral diphenhydramine Administer oxygen Maintain patent airway