Volume of distribution:

Correct Answer: D

Rationale: Volume of distribution (Vd) is a pharmacokinetic parameter reflecting the extent a drug distributes into body tissues relative to plasma. It's not always a real volume, as it can exceed total body water (e.g., for lipophilic drugs), making that statement false. The second option is nonsensical due to unclear phrasing, but likely intends a ratio that's incorrectly stated. The third option reverses the correct formula and is also gibberish. The accurate definition is the amount of drug in the body divided by its concentration in plasma (Vd = Dose / Cp), which quantifies how widely a drug disperses. This isn't about area under the curve (AUC) or dose, as some might confuse with clearance. Understanding Vd is crucial for dosing adjustments, especially for drugs with high tissue affinity, where a large Vd indicates extensive distribution beyond plasma, impacting therapeutic strategies.

Correct Answer: A

Rationale: When taking Digoxin, low levels of potassium can cause toxicity because digoxin competes with potassium for binding sites on the sodium-potassium pump in cardiac cells. Low potassium levels can lead to increased binding of digoxin to the pump, resulting in increased intracellular calcium levels and an increased risk of digoxin toxicity, including arrhythmias. Therefore, monitoring and maintaining adequate potassium levels are crucial in patients taking digoxin to prevent toxicity.

Correct Answer: A

Rationale: The nurse should include the instruction to avoid drinking large amounts of green tea when providing dietary teaching for a patient receiving warfarin therapy. Green tea is high in vitamin K, which can interfere with the effectiveness of warfarin, an anticoagulant medication. Maintaining a consistent intake of vitamin K is important for patients on warfarin in order to keep their INR (International Normalized Ratio) levels stable. It is not necessary to avoid all sources of vitamin K, but rather to keep intake consistent and moderate. Drinking large amounts of green tea, which is high in vitamin K, can potentially impact the patient's INR levels and increase the risk of bleeding or clotting issues.

Correct Answer: D

Rationale: The most common undesirable effect of thrombolytic therapy is internal and superficial bleeding. Thrombolytic medications work by dissolving blood clots, which can lead to an increased risk of bleeding. This bleeding can occur internally, such as in the gastrointestinal tract or brain, or externally, in the form of bruising or easy bleeding from cuts or wounds. It is crucial for healthcare providers to closely monitor patients receiving thrombolytic therapy for signs of bleeding and to promptly address any concerns to prevent complications. Dysrhythmias, nausea and vomiting, and anaphylactic reactions are less common adverse effects associated with thrombolytic therapy compared to bleeding.

Correct Answer: A

Rationale: Digoxin is a medication commonly used to treat heart conditions such as heart failure and atrial fibrillation. Monitoring and reporting adverse effects of digoxin are crucial to ensure the patient's safety.