The patient stops breathing shortly after the nurse institutes inhaled bronchodilator therapy, as ordered. After initial ventilation with a bag-valve-mask device, the patient achieves good bilateral chest rising. He is then intubated with an orotracheal tube, and ventilation is continued. A repeat ABG analysis indicates pH, 7.12, PCO2 55 mmHg, PO2 33 mmHg, and HCO3 – 25 mEq/L. No loss of vital signs is noted. The patient is then given 100 mEq of sodium bicarbonate. Ten minutes later, ABG analysis indicates pH, 7.55, PCO2 35 mmHg, PO2 425 mmHg, and HCO3 – 36.5 mEq/L. Based on the latest ABG results, the nurse knows that the patient is exhibiting signs of: