A 65-year-old male with a history of chronic obstructive pul…

A 65-year-old male with a history of chronic obstructive pulmonary disease (COPD) is admitted to the emergency department complaining of severe dyspnea, persistent cough with increased sputum production, and lethargy.  Upon examination, he appears anxious and is using accessory muscles to breathe.  His VS are: HR 110 bpm, RR 30, BP 150/90 mmHg, and SaO2 88% on RA.  An arterial blood gas (ABG) is drawn with the following results: ph: 7.28 PaCO2: 65 mmHg PaO2: 55 mmHg HCO3: 30 mEq/L Oxygen Saturation (Sao2): 85% Based on the ABG results and the patient’s clinical presentation, what is the most likely acid-base disorder?