A client comes to the emergency department with acute shortness of breath and a cough that produces pink, frothy sputum. the client is restless and extremely anxious. admission assessment reveals crackles and wheezes, a blood pressure of 82/45 mmhg, a heart rate of 120 bpm, and a respiratory rate of 38 breaths/min. the client's medical history includes hypertension, and heart failure. what is the nurse's priority intervention?