A client is prescribed 25 mg/kg of a medication. The weight of the client is 42 kg.
How many milligrams (mg) of medication should be administered to achieve the total prescribed dose?

This answer is correct because BSA is the most accurate method for calculating the child's dose from the adult dose¹². BSA takes into account the child's weight and height, and reflects the physiological function and organ growth of the child beter than weight alone¹. BSA can be calculated using a nomogram or a formula based on the child's weight and height¹. The child's dose can then be calculated by multiplying the adult dose by the ratio of the child's BSA to the average adult BSA (1.73 m2)¹. For example:

Child dose by BSA = (mg/day) = Adult Dose in mg/day x BSA in m2 / 1.73

OR

Child dose by BSA = (mg/day) = Adult Dose in mg/m2 x BSA in m2

The other options are not correct because they are not accurate methods for calculating the child's dose from the adult dose. Actual body weight and ideal body weight may not account for individual variations in pharmacokinetics, pharmacodynamics, or clinical response. Actual body height is not a reliable indicator of drug dosage, as it does not reflect the body mass or organ function of the child.

This action should be taken by the nurse before administering the medication because the use of a trailing zero after a decimal point (5.0 mg) is a common cause of medication errors and should be avoided. A trailing zero may be misread or misinterpreted as a larger dose (50 mg) or omited altogether, resulting in a 10-fold overdose or underdose, respectively. For example, when prescriptions have been writen for "Coumadin 1.0 mg," patients have received 10 mg in error. Therefore, the nurse should clarify the intended dose with the healthcare provider and use the correct notation (5 mg) without a trailing zero.

The other options are not appropriate actions because:

a) Discussing the use of PO (by mouth) with the healthcare provider is not necessary, as PO is a standard route of administration for Haldol (haloperidol) and does not pose a risk of confusion or error.

b) Discussing the use of tid (three times a day) with the healthcare provider is not necessary, as tid is a standard frequency of administration for Haldol and does not pose a risk of confusion or error.

c) Discussing the use of Haldol with the healthcare provider is not relevant to the question, as Haldol is the prescribed medication for the patient who is agitated and does not need to be changed or questioned by the nurse.