Questions: A nurse is preparing to administer cefaclor 40 mg / kg / day PO divided in equal doses every 8 hr to a child who weighs 48 lb. Available is cefacior suspension 375 mg / 5 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.) 3.9 mL

Solution Steps

To convert the child's weight from pounds to kilograms, we use the conversion factor \( 1 \text{ lb} = 0.453592 \text{ kg} \): \[ \text{Weight in kg} = 48 \text{ lb} \times 0.453592 \text{ kg/lb} \approx 21.77 \text{ kg} \]

The total daily dose of cefaclor is calculated using the formula: \[ \text{Total Daily Dose (mg)} = \text{Weight (kg)} \times 40 \text{ mg/kg/day} \] Substituting the weight: \[ \text{Total Daily Dose (mg)} \approx 21.77 \text{ kg} \times 40 \text{ mg/kg/day} \approx 870.90 \text{ mg} \]

Since the medication is administered every 8 hours, there are \( 3 \) doses in a day: \[ \text{Dose per Administration (mg)} = \frac{\text{Total Daily Dose (mg)}}{3} \approx \frac{870.90 \text{ mg}}{3} \approx 290.30 \text{ mg} \]

The concentration of the cefaclor suspension is given as \( 375 \text{ mg} / 5 \text{ mL} \), which simplifies to: \[ \text{Concentration} = \frac{375 \text{ mg}}{5 \text{ mL}} = 75 \text{ mg/mL} \] To find the volume in mL for the dose per administration: \[ \text{Dose per Administration (mL)} = \frac{\text{Dose per Administration (mg)}}{\text{Concentration (mg/mL)}} \approx \frac{290.30 \text{ mg}}{75 \text{ mg/mL}} \approx 3.87 \text{ mL} \] Rounding to the nearest tenth gives: \[ \text{Dose per Administration (mL)} \approx 3.9 \text{ mL} \]

Final Answer