The nurse plans to administer the adult client’s prescriptions which are metoprolol, hydrochlorothiazide, enoxaparin and atorvastatin. The current laboratory values are; Serum potassium 5.2 mmol/L, Platelet Count 98,000/mm, Serum cholesterol 250 mg/dL and Serum Creatinine 1.2 mg/dL. Which medication should the nurse hold and notify the prescriber?