Jenny Smith, a 14-year-old girl with asthma, had been under relatively good control until last night. She slept over at a friend's house and woke up in the middle of the night with severe shortness of breath ("dyspnea") and a cough (unproductive of sputum). She had expiratory wheezing. Unfortunately, she did not take her bronchodilator medication with her to her friend's house. She was taken to the emergency walk-in clinic. On physical exam, she was wheezing quite loudly and using her accessory muscles of respiration to help her breathe. A chest X-ray revealed hyperluscent and over-inflated lungs. Blood testing revealed an arterial blood pH of 7.25 (normal = 7.35-7.45). Pulmonary function testing revealed the graph shown below.