100 units of regular Humulin insulin in 100 mL 0.9% NS were to be infused at 4 mL/hr. How many units per hour will be delivered? (ROUND TO WHOLE NUMBER: LABEL CORRECTLY TO RECEIVE CREDIT)

Choice A rationale

Inflammation of the gallbladder, or cholecystitis, typically causes pain in the right upper quadrant of the abdomen, often radiating to the right shoulder or back. While percussion can elicit tenderness, the primary location of pain is not the costovertebral angle, which is anatomically associated with the kidneys.

Choice B rationale

Sharp pain along the costovertebral angles (CVA) during percussion is a classic clinical sign known as CVA tenderness. This finding is highly indicative of inflammation or infection of the kidneys, such as pyelonephritis. The kidneys are retroperitoneal organs located just below the twelfth rib, making them directly accessible to percussion at this anatomical landmark.

Choice C rationale

Enlargement of the liver, or hepatomegaly, is typically assessed by palpation and percussion of the right upper quadrant, below the costal margin. While it can cause discomfort, liver enlargement does not primarily manifest as pain at the costovertebral angles upon percussion.

Choice D rationale

Pancreatitis, inflammation of the pancreas, usually causes severe epigastric pain that often radiates to the back. While it is a retroperitoneal organ, its anatomical location and the nature of the pain differ significantly from the localized tenderness elicited at the costovertebral angles during percussion.

Choice A rationale

The abdomen, specifically 2 inches from the umbilicus, is a common site for subcutaneous injections due to the presence of ample adipose tissue, which allows for slower absorption of medications like insulin or heparin. Intradermal injections require a site with a thin epidermis and minimal subcutaneous tissue to ensure the medication remains within the dermal layer, making the abdomen unsuitable.

Choice B rationale

The anterior thigh is a common site for intramuscular injections, particularly in infants, due to the large muscle mass (vastus lateralis). While it can be used for subcutaneous injections, its muscularity and varying skin thickness make it less ideal for the precise shallow angle required for an intradermal injection, where the goal is to deposit the medication into the dermis.

Choice C rationale

The posterior upper arm, specifically the triceps area, is frequently utilized for subcutaneous injections, such as insulin or certain vaccines, because it offers sufficient subcutaneous tissue. However, similar to the anterior thigh, its anatomical characteristics with thicker skin and subcutaneous fat layers make it less optimal for the very superficial intradermal injection technique.

Choice D rationale

The upper chest, particularly below the clavicle and above the breasts, is an appropriate site for intradermal injections. This area, along with the inner forearm and upper back, has a thin epidermis and less subcutaneous tissue, which facilitates the proper placement of the medication within the dermis, allowing for the formation of a visible wheal, a key indicator of a successful intradermal injection.