A client who is experiencing recurrent seizures is prescribed a 1,000 mg intravenous (IV) loading dose of phenytoin. The client currently has a continuous primary IV infusion of 5% dextrose in water (D5W) running at 75 mL/hr through a peripheral catheter. What is the safest administration sequence for the nurse to implement?
- AAdminister the medication concurrently with the continuous fluids through a proximal Y-site connector to maintain hydration status during the infusion.
- BAdd the ordered dose directly into a 100 mL bag of 5% dextrose in water and infuse it as a secondary piggyback to prevent fluid volume overload.
- Dilute the medication in 0.9% sodium chloride, pause the primary fluids, flush the catheter with 0.9% sodium chloride, and administer the dose through an in-line filter.Answer
- DCalculate the necessary drip rate to infuse the entire 1,000 mg dose rapidly over 5 minutes, ensuring therapeutic serum levels are quickly achieved.
Answer
The safest action is to dilute the phenytoin in 0.9% sodium chloride, pause the primary dextrose infusion, flush the IV line with 0.9% sodium chloride before and after administration, and use an in-line filter.
Phenytoin is highly incompatible with dextrose-containing solutions and will form a solid precipitate if mixed. To safely administer the loading dose, the nurse must dilute it only in 0.9% sodium chloride (normal saline), stop the primary D5W infusion, flush the IV catheter with normal saline before and after administration, and use an in-line filter to catch any potential microscopic crystallization. Additionally, the infusion rate must not exceed 50 mg/minute to prevent severe hypotension and cardiac arrhythmias.
Step-by-Step Solution
Key Concept
Phenytoin IV administration requires strict compatibility checks (only compatible with normal saline), the use of an in-line filter, and adherence to a maximum infusion rate of 50 mg/minute to prevent precipitation and severe cardiovascular toxicity.