What is the primary BP effect of β-adrenergic blockers such as atenolol (Tenormin)?

Correct Answer: C

Rationale: The correct answer is C) Decrease CO by decreasing rate and strength of the heart and renin secretion by the kidneys. Beta-adrenergic blockers like atenolol primarily work by blocking the beta-adrenergic receptors in the heart and kidneys. By doing so, they decrease the heart rate and contractility, leading to a reduction in cardiac output (CO). This results in a decrease in blood pressure (BP) as the heart is pumping with less force. Option A is incorrect because vasodilation by blocking calcium movement is associated with calcium channel blockers, not beta-blockers. Option B is incorrect because blocking aldosterone leads to sodium and water retention, not reduction, and this would not significantly affect BP. Option D is incorrect as beta-blockers do not directly inhibit sympathetic outflow, rather they block the response of the heart to sympathetic stimulation. In an educational context, understanding the mechanisms of action of medications like beta-blockers is crucial for healthcare professionals in managing patients with cardiovascular conditions. Knowing how these drugs affect BP helps in making informed decisions regarding treatment options and monitoring for potential side effects.

Correct Answer: A

Rationale: The correct answer is A) ECG changes present at the onset of the pain. This is the differentiating factor between unstable angina and myocardial infarction (MI). In unstable angina, ECG changes are usually transient or absent, whereas in MI, ECG changes indicating myocardial damage such as ST-segment elevation or Q waves are typically present. Option B) A chest x-ray indicating left ventricular hypertrophy is not a specific marker for either unstable angina or MI. Left ventricular hypertrophy can be seen in various cardiac conditions and is not a distinguishing feature between the two. Option C) Appearance of troponin in the blood 48 hours after the infarct is a marker for MI but not specific to differentiate unstable angina from MI. Troponin levels rise within a few hours after MI, not 48 hours later. Option D) Creatine kinase (CK)-MB enzyme elevations that peak 18 hours after the infarct are indicative of MI but again not helpful in differentiating unstable angina from MI as CK-MB levels can also rise in other conditions causing myocardial damage. Understanding the distinctions between unstable angina and MI is crucial in clinical practice as the management and urgency of treatment differ significantly between the two conditions. Recognizing the specific diagnostic markers helps healthcare providers make accurate and timely decisions to provide the best care for patients presenting with chest pain related to cardiovascular issues.

Correct Answer: A

Rationale: In the context of a patient hospitalized after sudden cardiac death (SCD), the most important nursing intervention is A) Continuous ECG monitoring. This is crucial because it allows for real-time monitoring of the patient's cardiac rhythm, which is essential in detecting any potential arrhythmias or abnormalities promptly. Continuous ECG monitoring enables early identification of changes in the heart's electrical activity, which is critical in preventing another cardiac event. It provides valuable information on the patient's heart rate, rhythm, and conduction, allowing nurses to intervene promptly if any issues arise. Auscultation of the carotid arteries (Option B) may provide information on blood flow, but it does not directly monitor the patient's cardiac rhythm or electrical activity. Frequent assessment of heart sounds (Option C) is important but does not take precedence over continuous ECG monitoring in this scenario. Monitoring airway status and respiratory patterns (Option D) is essential for overall patient care, but in the immediate aftermath of SCD, ensuring continuous ECG monitoring takes priority due to the risk of recurrent cardiac events. In an educational context, understanding the rationale behind prioritizing interventions post-SCD is crucial for nurses caring for cardiac patients. It emphasizes the significance of continuous cardiac monitoring in preventing potential complications and guiding timely interventions to ensure optimal patient outcomes.

Correct Answer: C

Rationale: In this practice exam question about pneumothorax symptoms, the correct answer is C) Both A and B (Chest pain and Shortness of breath). Pneumothorax is a condition characterized by the presence of air in the pleural space, leading to lung collapse. Chest pain is a common symptom of pneumothorax due to irritation of the pleura. The presence of air in the pleural space also leads to lung compression, causing shortness of breath as the lung is unable to expand fully. Option A (Chest pain) is incorrect because pneumothorax does not typically cause localized chest pain, but rather a more generalized discomfort or sharp pain due to lung collapse. Option B (Shortness of breath) is incorrect as pneumothorax directly impacts lung function, leading to decreased lung capacity and difficulty breathing. Educationally, understanding the symptoms of pneumothorax is crucial for healthcare professionals, especially those working in emergency or critical care settings. Recognizing these symptoms promptly can lead to early diagnosis and intervention, potentially preventing further complications or progression of the condition. This knowledge is vital for providing timely and appropriate care to patients with pneumothorax.

Correct Answer: A

Rationale: In this scenario, the correct nursing action is to choose option A) call Mr. K.'s physician to report the PT result. A significantly elevated prothrombin time indicates a prolonged clotting time, which may lead to an increased risk of bleeding. Therefore, it is crucial to inform the physician promptly to ensure appropriate management. Option B) stopping the heparin infusion is incorrect because heparin is an anticoagulant used to prevent blood clots, and abruptly discontinuing it can lead to an increased risk of clot formation. Option C) increasing the heparin infusion is also incorrect as it would further exacerbate the anticoagulation effect, potentially leading to serious bleeding complications. Option D) doing nothing is not the appropriate course of action when faced with a critical lab result that can impact patient safety. Educationally, understanding the significance of prothrombin time values is vital for nurses caring for patients on anticoagulant therapy. This knowledge helps in recognizing abnormal results, taking appropriate actions, and collaborating effectively with the healthcare team to ensure patient safety and optimal outcomes.