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 cefactor 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.)

This question is solved by proportions.

Step 1:

A nurse is preparing to administer cefaclor 40 mg/kg/day.

This means that the first step is finding the baby's weight in kg.

The child weighs 48lb. Each lb has 0,453592kg.

So the child weighs 48*0.453592 = 21.7724kg.

Step 2:

Here, we find the daily dose.

For each kg, the baby is administered 40 mg.

Since the baby weighs 21.7724 kg, the daily dose is of 40*21.7724 = 870.896 mg.

Step 3:

Here, we find how many mL in a day.

For 375 mg, 5 mL are administered. How many mL for 870.896 mg?

375 mg - 5 mL

870.896 mg - x mL

Applying cross multiplication:

Step 4:

Here, we find how many mL per dose.

Equal doses every 8 hours, so 24/8 = 3 doses per day.

11.6/3 = 3.9

Thus, the nurse should administer 3.9 mL per dose.

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