The client in normal sinus rhythm with a peaked T wave.
A. (correct) A client with a peaked wave could be experiencing hyperkalemia. Changes in potassium levels can initiate cardiac dysrhythmias and instability.
B. (incorrect) Fluctuations in rate are expected in clients diagnosed with atrial fibrillation, and a heart rate of 100 is at the edge of a normal rate.
C. (incorrect) Most people experience an occasional premature ventricular contraction (PVC); this would not warrant the nurse assessing this client first.
D. (incorrect) A first-degree block is not an immediate problem.
TEST-TAKING HINT: The test taker must know the normal data so that the abnormal will be apparent. Normal heart rate is 60-100. The nurse should assess the client who has an abnormal or life-threatening condition.