A nurse is preparing to administer dexamethasone 0.5 mg/kg/day IM to divide equally every 6 hr to a client who weighs 132 lb. Available is dexamethasone 4 mg/mL. How many mL should the nurse administer per dose? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
The Correct Answer and Explanation is:
To determine the amount of dexamethasone the nurse should administer per dose, follow these steps:
- Convert the Client’s Weight to Kilograms:
The client’s weight is 132 lb. To convert pounds to kilograms, use the conversion factor (1 \text{ lb} = 0.4536 \text{ kg}):
[
\text{Weight (kg)} = 132 \text{ lb} \times 0.4536 \text{ kg/lb} = 59.87 \text{ kg} \approx 59.9 \text{ kg}
] - Calculate the Total Daily Dose:
The order is for 0.5 mg/kg/day. Thus, calculate the total daily dose as follows:
[
\text{Total daily dose (mg)} = 0.5 \text{ mg/kg/day} \times 59.9 \text{ kg} = 29.95 \text{ mg} \approx 30.0 \text{ mg}
] - Determine the Dose per Administration:
The daily dose needs to be divided into doses administered every 6 hours. There are 24 hours in a day, so:
[
\text{Number of doses per day} = \frac{24 \text{ hours}}{6 \text{ hours/dose}} = 4 \text{ doses/day}
]
Therefore, the dose per administration is:
[
\text{Dose per administration (mg)} = \frac{30.0 \text{ mg}}{4} = 7.5 \text{ mg}
] - Calculate the Volume to Administer:
The available concentration is 4 mg/mL. To find out how many mL are needed for each dose:
[
\text{Volume to administer (mL)} = \frac{\text{Dose per administration (mg)}}{\text{Concentration (mg/mL)}} = \frac{7.5 \text{ mg}}{4 \text{ mg/mL}} = 1.875 \text{ mL}
]
Rounding this to the nearest tenth gives:
[
1.9 \text{ mL}
]
Summary: The nurse should administer 1.9 mL of dexamethasone per dose.