When monitoring patients on antitubercular drug therapy, the nurse knows that which drug may cause a decrease in visual acuity?

The question is about calculating the volume of phenytoin oral solution that the nurse should administer per dose. The client is prescribed 250 mg of phenytoin and the available solution has a concentration of 25 mg/5 mL.

Let’s calculate the volume step by step:

Step 1: Identify the prescribed dose and the concentration of the available medication. The prescribed dose is 250 mg and the concentration of the available medication is 25 mg/5 mL.

Step 2: Set up the calculation. We want to find out how many mL correspond to the prescribed dose. We can set up the calculation as follows: (Prescribed dose ÷ Concentration) × Volume.

Step 3: Substitute the known values into the calculation. This gives us: (250 mg ÷ 25 mg/5 mL).

Step 4: Perform the division operation first due to the order of operations (BIDMAS/BODMAS). This gives us: (250 mg ÷ 5 mg/mL).

Step 5: Perform the final calculation. This gives us: 50 mL.

So, the nurse should administer 50 mL of the phenytoin oral solution per dose.

Please note that this calculation assumes that the prescribed dose (250 mg) is to be administered in one go. If the dose is to be split over the day, the volume to be administered would change accordingly.

Choice A rationale:

Administering the medications using a 3-mL medication syringe is not the best practice. While it is possible to use a 3-mL syringe for medication administration, it is not the most efficient or safest method. A larger syringe allows for easier administration and reduces the risk of creating too much pressure which could potentially damage the PEG tube.

Choice B rationale:

Applying firm pressure on the syringe’s piston to infuse the medication is not recommended. This can create too much pressure in the PEG tube and could potentially cause damage. It is generally advised to allow the medication to flow into the tube via gravity. Choice C rationale:

Flushing the tubing with 30 mL of saline after the medication has been given is the correct technique. This helps to ensure that all of the medication has been administered and also helps to keep the tube clear of any potential blockages.

Choice D rationale:

Using the barrel of the syringe, allowing the medication to flow via gravity into the tube is a common practice. However, it is not the only step in the process. It is also important to flush the tube before and after medication administration to ensure all medication is delivered and to maintain the patency of the tube.