A patient with coronary artery disease is to start low-dose aspirin therapy.
What is the primary reason for this medication?

Choice A rationale

Administering a medication when there is a strong possibility the patient has already received it could lead to an overdose. The automated dispensing machine's record indicates removal of the dose, and the patient's statement, despite her confusion, suggests she might have taken it. The nurse's primary responsibility is patient safety and preventing medication errors, which this action would violate.

Choice B rationale

This is the safest course of action. The medication was removed from the machine, and the patient states she thinks she took it. The night shift nurse's failure to sign the MAR is a documentation error, but the potential for a double dose is a serious safety concern. The nurse should hold the dose and investigate further before administering anything to prevent an iatrogenic event.

Choice C rationale

Notifying the provider for a new order is an unnecessary and premature step. The issue is not that the medication is unavailable or the order is incorrect. The immediate concern is whether the patient has already received the dose. Holding the medication and verifying the administration is the correct first step, and the provider would not be contacted unless there was a clinical reason to do so, such as if the blood glucose became dangerously high.

Choice D rationale

Giving the insulin and then monitoring the patient is dangerous. Administering an additional dose of insulin could cause a severe hypoglycemic event, especially in a confused patient. The blood glucose of 142 mg/dL is not critically high, so there is no immediate need for the insulin, and the risk of a medication error outweighs any perceived benefit of administering the medication immediately.

Choice A rationale

When mixing insulin lispro (rapid-acting) with NPH (intermediate-acting), it is a standard and crucial procedure to draw the clear rapid-acting insulin first, followed by the cloudy NPH insulin. This is to prevent the contamination of the rapid-acting vial with the NPH suspension, which could alter the rapid-acting insulin's predictable onset and peak.

Choice B rationale

While unopened insulin vials should be stored in the refrigerator, the patient's current in-use vials can be stored at room temperature for up to 28 days to make injections more comfortable. Injecting cold insulin can cause discomfort and lipohypertrophy at the injection site. However, the refrigerator is where all unopened vials are stored.

Choice C rationale

Shaking the insulin for a full minute is not recommended. Vigorous shaking can cause foaming and bubble formation, which can lead to inaccurate dosing. NPH insulin, a suspension, should be gently rolled between the palms to ensure uniform mixing and proper suspension of the particles, which prevents clumping and allows for accurate dosing.

Choice D rationale

Administering an injection at a 30-degree angle is not standard practice for subcutaneous insulin injections. Insulin is injected into the subcutaneous fat layer. A 90-degree angle is commonly used for most patients, and a 45-degree angle may be used for very thin individuals or for injections into the arms. A 30-degree angle is not correct.