A client receives an opioid for postoperative pain. One hour…

A client receives аn оpiоid fоr postoperаtive pаin. One hour later, the client is difficult to arouse and has shallow respirations at 8/min. ABG results are: pH: 7.28 PaCO₂: 58 mm Hg HCO₃⁻: 25 mEq/L PaO₂: 72 mm Hg Based on these findings, identify the acid–base imbalance.