The nurse is caring for a client who had a permanent pacemaker inserted because of a complete heart block. The nurse determines that which of the following client outcomes indicates a successful procedure?

Correct Answer: D

Rationale: The correct answer is D because a permanent pacemaker is inserted to address heart blocks by providing electrical stimulation to maintain an appropriate heart rate. In this case, the client having paced beats at the rate of 68 per minute indicates that the pacemaker is functioning effectively. Choice A is incorrect as ambulating without dyspnea or chest pain does not specifically indicate the success of the pacemaker procedure. Choice B is incorrect because a normal sinus rhythm would not be expected in a client with a permanent pacemaker. Choice C is incorrect as the heart rate of 80 beats per minute may not be indicative of the pacemaker's effectiveness, as the client may be paced at a different rate. Blood pressure values alone do not indicate the success of the pacemaker insertion.

Correct Answer: D

Rationale: The correct answer is D: Unstable angina. Unstable angina is characterized by chest pain that is increasing in intensity and duration, indicating an imminent heart attack. This type of angina is considered a medical emergency requiring immediate intervention. Stable angina (choice A) is chest pain that occurs predictably with exertion and resolves with rest. Variant angina (choice B) is caused by coronary artery spasm and is typically relieved by medication. Predictable angina (choice C) is not a recognized term in cardiology. Therefore, the critical care nurse should identify the patient's symptoms as consistent with unstable angina due to the escalating nature of the chest pain.

Correct Answer: A

Rationale: The correct answer is A: P wave. The P wave represents atrial depolarization in an ECG strip, typically measuring around 0.06 to 0.1 seconds. This is the first wave in the ECG waveform sequence. The PRI (B) measures the time from the start of the P wave to the start of the QRS complex, the QRS complex (C) represents ventricular depolarization, and the QT interval (D) measures the time from the start of the QRS complex to the end of the T wave. Therefore, the P wave is the most fitting choice based on the given information.

Correct Answer: D

Rationale: The correct answer is D: Reducing afterload. ACE inhibitors reduce afterload by inhibiting the conversion of angiotensin I to angiotensin II, leading to vasodilation and decreased systemic vascular resistance. This reduces the workload on the heart, improves cardiac output, and helps in managing heart failure. A, increasing preload, would worsen heart failure by increasing the volume of blood returning to the heart. B, causing vasoconstriction, is incorrect as ACE inhibitors actually cause vasodilation. C, increasing afterload, would also worsen heart failure by increasing the resistance the heart must pump against.