What is the appropriate medication dosage for the patient as needed?

Choice A rationale:

Intravenous (IV) administration delivers medication directly into the bloodstream. This route is not appropriate for insulin because it would result in a rapid and potentially dangerous drop in blood glucose levels. Insulin needs to be absorbed more slowly to mimic the natural release of insulin from the pancreas.

IV administration also requires sterile technique and specialized equipment, making it more complex and time-consuming than subcutaneous injection.

Additionally, there is a higher risk of infection and other complications with IV administration.

Choice B rationale:

The vastus lateralis is a muscle in the thigh that is commonly used for intramuscular (IM) injections. However, IM injections are not typically used for insulin administration because they can be more painful and have a slower absorption rate than subcutaneous injections.

IM injections also carry a higher risk of hitting a blood vessel, which could lead to erratic absorption of insulin.

Choice D rationale:

The deltoid is a muscle in the upper arm that can be used for subcutaneous injections. However, the abdomen is generally the preferred site for insulin injection because it has a greater amount of subcutaneous fat, which helps to slow the absorption of insulin and provide a more consistent effect.

The abdomen is also a more convenient site for self-injection, as it is easily accessible.

Choice C rationale:

The fatty tissue of the abdomen is the ideal site for subcutaneous insulin injection because it provides slow and consistent absorption of insulin.

The abdomen has a rich blood supply, which helps to distribute the insulin throughout the body.

The subcutaneous tissue in the abdomen is relatively thin, which makes it easy to inject insulin without causing pain or discomfort.

The abdomen is also a large area, which allows for multiple injection sites to be used and rotated to prevent lipohypertrophy (thickening of the subcutaneous tissue).

Choice A rationale:

A patient's last bowel movement being 4 days ago does not directly increase their risk of pulmonary embolism (PE). While constipation can be a risk factor for deep vein thrombosis (DVT), which can lead to PE, it is not a significant risk factor on its own.

It's important to assess for other risk factors for DVT, such as immobility, recent surgery, or a history of blood clots, in conjunction with constipation.

Choice C rationale:

A platelet count of 45,000/mm^3 is low (thrombocytopenia), but it does not directly increase the risk of PE.

In fact, a low platelet count can sometimes hinder clot formation. However, it's important to monitor patients with thrombocytopenia for bleeding risks, as they may be more prone to bleeding complications.

Choice D rationale:

While receiving a transfusion of two units of packed red blood cells can increase blood viscosity, which could theoretically slightly increase the risk of PE, it is not a major risk factor.

Patients who receive transfusions are often already at an elevated risk of PE due to other underlying conditions or surgeries. It's essential to assess for other risk factors in these patients.