A physician ordered magnesium sulfate 2 grams per hour for a maintenance dose. There are 40 grams of magnesium sulfate in 1 liter of lactated Ringers solution.
What is the rate per hour to administer the maintenance dose?

To find the amount of solution to draw for one dose, you need to calculate the following:

- The body surface area (BSA) of the client in square meters (m²) using the formula: BSA (m²) = √(Height (cm) x Weight (kg) / 3600)
- The dose of allopurinol in milligrams (mg) using the formula: Dose (mg) = BSA (m²) x Prescribed dose
(mg/m²)
- The volume of solution in milliliters (mL) using the formula: Volume (mL) = Dose (mg) / Concentration (mg/mL)

First, use the formula for BSA to find the client's body surface area in square meters:

BSA (m²) = √(Height (cm) x Weight (kg) / 3600)

Since the client's height is 148 cm and weight is 55 kg, plug in these values into the formula:

BSA (m²) = √(148 cm x 55 kg / 3600)

Simplify and solve for the BSA:

BSA (m²) = 1.41 m²

Next, use the formula for dose to find the amount of allopurinol in milligrams:

Dose (mg) = BSA (m²) x Prescribed dose (mg/m²)

Since the client's BSA is 1.41 m² and the prescribed dose is 115 mg/m², plug in these values into the formula:

Dose (mg) = 1.41 m² x 115 mg/m²

Simplify and solve for the dose:

Dose (mg) = 162.15 mg

Then, use the formula for volume to find the amount of solution in milliliters:

Volume (mL) = Dose (mg) / Concentration (mg/mL)

Since the dose is 162.15 mg and the concentration is 25 mg/mL, plug in these values into the formula:

Volume (mL) = 162.15 mg / 25 mg/mL

Simplify and solve for the volume:

Volume (mL) = 6.486 mL

Therefore, the nurse should draw **6.486 mL** of solution for one dose of allopurinol.

Insulin is a hormone that helps regulate blood sugar levels. It is usually injected into the fat layer just under the skin (subcutaneous or SubQ) using a syringe and needle or a pen-like device². Insulin syringes are marked in units of insulin, not milliliters or cubic centimeters. The most common insulin syringe holds 1 mL of fluid and has markings for 100 units of insulin². A U-100 syringe means that for every 1 mL of fluid, there are 100 units of insulin³.
To administer 14 units of insulin, you would need to draw up 0.14 mL of fluid in a U-100 syringe. You would inject the insulin into your abdomen, upper arm, butocks, hip, or the front or side of the thigh¹. You would use a different area within the site each time you inject insulin to prevent lumps, swelling, or thickened skin¹.

The other options are incorrect because:

b) There is no need to divide the dose into two injections. This would increase the risk of infection and pain.

c) A tuberculin syringe is not designed for insulin administration. It is marked in milliliters or cubic centimeters, not units of insulin. Using a tuberculin syringe could result in an incorrect dose of insulin.

d) The timing of insulin administration depends on the type and duration of insulin. Some insulins are taken before meals, some are taken after meals, and some are taken once or twice a day. The primary healthcare provider should specify when to take the insulin.