The nurse is caring for a client who has had a temporary transvenous pacemaker inserted. The cardiac monitor shows pacemaker spikes occurring at various points in the client's own beats such as on the T wave. What action is the nurse's priority?

A. Diltiazem is a calcium channel blocker that can be used to manage conditions like atrial fibrillation or hypertension by slowing the heart rate and reducing blood pressure. However, it may not be the most appropriate drug in the acute setting for heart failure with dyspnea.
B. Nitroglycerine is a vasodilator that helps reduce preload and afterload, which can be beneficial in heart failure. However, it primarily works by reducing the workload on the heart and may help with fluid overload but may not directly address anxiety.
C. Verapamil is another calcium channel blocker that slows the heart rate and reduces the heart's workload. While it may be useful for controlling tachyarrhythmias, it is not the best option for managing acute heart failure with severe dyspnea and anxiety.
D. Morphine is an opioid that can be used in acute heart failure to reduce both anxiety and respiratory distress. It works by reducing the sympathetic nervous system response, decreasing heart rate and blood pressure, and providing a sense of calm, which reduces anxiety. It also reduces preload by venodilation and helps manage severe dyspnea.

A. Mobitz II is a type of second-degree AV block characterized by constant PR intervals and sudden dropped QRS complexes (i.e., the PR interval does not lengthen progressively). This is a more serious block because the dropped beats are unpredictable and could lead to complete block.
B. Sinus bradycardia is a slower-than-normal heart rate (usually less than 60 beats per minute) that originates from the sinus node. First-degree AV block is characterized by a prolonged PR interval, but unlike second-degree block, there are no dropped QRS complexes.
C. Mobitz I (Wenckebach) is a second-degree AV block where the PR interval gradually lengthens with each successive beat until a QRS complex is dropped. After the dropped beat, the cycle repeats. This is a relatively benign block and often resolves without intervention, though it requires monitoring.
D. Third-degree heart block (also known as complete heart block) occurs when there is no communication between the atria and ventricles. The atria and ventricles beat independently of each other. There are no relationship between the P waves and QRS complexes, and the ventricular rate is typically slower than the atrial rate.