A nurse will administer Nubain (nalbuphine) 0.3 mg/kg IV over 10 minutes. The Nubain is available in 10 mg/mL. The patient weighs 148 lb.
How many milliliters per minute of Nubain should the nurse administer?
A.
0.2 mL/min
B.
0.4 mL/min
C.
1 mL/min
D.
2 mL/min
E.
2 mL/min
The correct answer and Explanation is :
To determine the correct flow rate of Nubain (nalbuphine) to administer, we first need to calculate the total dose required based on the patient’s weight and then determine the administration rate in milliliters per minute.
Step 1: Convert the patient’s weight from pounds to kilograms.
The patient weighs 148 lb. To convert pounds to kilograms, we use the conversion factor:
[
1 \text{ lb} = 0.453592 \text{ kg}
]
Calculating the weight in kilograms:
[
148 \text{ lb} \times 0.453592 \text{ kg/lb} \approx 67.13 \text{ kg}
]
Step 2: Calculate the total dose of Nubain required.
The prescribed dose is 0.3 mg/kg. Therefore, the total dose can be calculated as follows:
[
\text{Total dose} = 0.3 \text{ mg/kg} \times 67.13 \text{ kg} \approx 20.14 \text{ mg}
]
Step 3: Convert the total dose to milliliters.
Nubain is available in a concentration of 10 mg/mL. To find out how many milliliters are needed for the total dose:
[
\text{Total volume (mL)} = \frac{\text{Total dose (mg)}}{\text{Concentration (mg/mL)}}
]
Calculating:
[
\text{Total volume (mL)} = \frac{20.14 \text{ mg}}{10 \text{ mg/mL}} \approx 2.014 \text{ mL}
]
Step 4: Determine the administration rate in mL/min.
The nurse is instructed to administer this volume over 10 minutes. To find the flow rate in mL/min, we use:
[
\text{Flow rate (mL/min)} = \frac{\text{Total volume (mL)}}{\text{Time (min)}}
]
Calculating the flow rate:
[
\text{Flow rate (mL/min)} = \frac{2.014 \text{ mL}}{10 \text{ min}} \approx 0.2014 \text{ mL/min}
]
Conclusion
Rounding to one decimal place, the flow rate is approximately 0.2 mL/min. Thus, the correct answer is:
A. 0.2 mL/min
This careful calculation ensures the patient receives the appropriate dose of medication safely and effectively.