What Acid-base Imbalance Does Mr. Santos Most Likely Have

Mr. Santos, a 55-year-old Patient, Is Admitted to the Hospital with Respiratory Distress. He Has a History of Chronic Obstructive Pulmonary Disease (COPD) . Arterial Blood Gas (ABG) Analysis Reveals Ph of 7.28, Paco2 of 60 Mmhg and HCO3- of 28 Meq/l