Questions: A nurse is to administer Hepatitis B vaccine 0.005 mg IM to a 19-month-old girl. How much of the vaccine should be prepared for administration? A. 0.50 ml, given that 0.01 mg / ml B. 1.20 ml C. 0.75 ml D. 1.80 ml

The answer is the first one (A): 0.50 ml.

Let's break down the reasoning:

1. The nurse needs to administer 0.005 mg of the Hepatitis B vaccine.
2. The concentration of the vaccine is given as 0.01 mg/ml.

To find out how much volume (in ml) is needed to administer 0.005 mg, we use the formula:

\[ \text{Volume (ml)} = \frac{\text{Dose (mg)}}{\text{Concentration (mg/ml)}} \]

Substituting the given values:

\[ \text{Volume (ml)} = \frac{0.005 \text{ mg}}{0.01 \text{ mg/ml}} \]

\[ \text{Volume (ml)} = 0.5 \text{ ml} \]

Therefore, the correct answer is A: 0.50 ml.

Explanation for each option:

• A. 0.50 ml: Correct, as calculated above.
• B. 1.20 ml: Incorrect, this would be the volume for a different dose.
• C. 0.75 ml: Incorrect, this would be the volume for a different dose.
• D. 1.80 ml: Incorrect, this would be the volume for a different dose.

In summary, the nurse should prepare 0.50 ml of the Hepatitis B vaccine for administration.