4 mcg = mg (LABEL CORRECTLY)

Choice A rationale

Administering nitroglycerin on an as-needed basis for sudden, crushing chest pain is inappropriate because the immediate nature of the pain requires rapid intervention. Myocardial ischemia, often causing such pain, necessitates swift vasodilation to improve coronary blood flow and oxygen supply, preventing irreversible cardiac muscle damage. Delay can exacerbate ischemia.

Choice B rationale

Administering nitroglycerin on a prescribed schedule is typically reserved for prophylactic use in conditions like stable angina to prevent episodes, not for acute, sudden onset chest pain. This type of pain indicates an acute event, potentially myocardial infarction, demanding immediate action to mitigate cardiac damage through rapid vasodilation.

Choice C rationale

Administering medication at the earliest convenience is not appropriate for a STAT order in a patient experiencing sudden, crushing chest pain. "STAT" signifies an urgent need for the medication, indicating a life-threatening or rapidly evolving condition requiring immediate pharmacological intervention to avert significant physiological compromise.

Choice D rationale

Administering nitroglycerin immediately is crucial for sudden, crushing chest pain as it suggests acute myocardial ischemia or infarction. Nitroglycerin causes vasodilation, reducing preload and afterload, which decreases myocardial oxygen demand and improves coronary blood flow, thereby limiting cardiac damage and alleviating symptoms rapidly.

Choice A rationale

The ventrogluteal muscle is a preferred site for Z-track injections due to its thick musculature, which minimizes the risk of hitting nerves or blood vessels. Its anatomical location provides a deep, safe space for medication deposition, allowing for effective sealing of the drug within the muscle tissue, preventing leakage and irritation to subcutaneous tissues.

Choice B rationale

The deltoid muscle is generally not preferred for Z-track injections because its smaller muscle mass and proximity to the radial nerve and brachial artery increase the risk of neurovascular injury. While used for some intramuscular injections, the Z-track technique benefits from larger muscle groups to effectively seal the medication.

Choice C rationale

The dorsogluteal muscle, though historically used, is considered less ideal than the ventrogluteal site for Z-track injections due to a higher risk of sciatic nerve injury and penetration of major blood vessels. However, its large muscle mass can still accommodate Z-track injections when alternative sites are contraindicated, if proper landmarks are meticulously observed.

Choice D rationale

The abdomen, 2 inches from the umbilicus, is primarily used for subcutaneous injections, not intramuscular Z-track injections. This area lacks the deep muscle tissue necessary to effectively deposit and seal medication using the Z-track technique, and attempting intramuscular injection here poses a high risk of hitting vital organs.

Choice E rationale

The posterior thigh, specifically the rectus femoris or vastus lateralis, can be used for intramuscular injections, but it is not a primary preferred site for the Z-track technique in adults due to varying muscle thickness and increased potential for discomfort. The ventrogluteal site generally offers a larger and safer muscle mass.