Calculation 3.0 Dosage by Weight Test
A nurse is preparing to administer epoetin alfa 50 units/kg subcutaneous toa preschooler who weighs 40 lb. Available is epoetin alfa 2,000 units/ml. How many ml should the nurse administer? (Round to the nearest whole number. Use a leading 0 if it applies. Don't use a trailing zero.) - ~ANSWER 2.2 lb/kg = 40 lb -> 18.181818 kg
50 units/kg x 18.181818 kg = 909.090909 units
2,000 units/ml = 909.090909 units -> 0.454545ml ANS: 0.45 ml
A nurse is preparing to administer phenytoin 5 mg/kg/day PO divided equally every 12 hr for an infant who weighs 12 lb 4 oz. How many mg should the nurse administer per dose? (Round to the nearest whole number. Use a leading 0 if it applies. Don't use a trailing zero.) - ~ANSWER 16 oz/lb x 4 oz = 0.25lb
12 lb + 0.25 lb = 12.25 lb
2.2 lb/kg x 12.25 lb = 5.568181 kg
5 mg/kg x 5.568181 kg = 27.840909 mg
27.840909 mg / 2(Q12H) = 13.920454 mg ANS: 13.9 mg
A nurse is preparing to administer erythromycin ethyl succinate 50 mg/kg/day PO divided in equal doses every 6 hr to a toddler who weighs 32 lb. Available is erythromycin ethylsuccinate suspension 200mg/5ml. How many ml should the nurse administer per dose? (Round to the nearest whole number. Use a leading 0 if it applies. Don't use a trailing zero.) - ~ANSWER 2.2 lb/kg x 32 lb = 14.545454 kg
50 mg/kg x 14.545454 kg = 727.272727 mg
727.272727 mg / 4 (Q6H) = 181.818181 mg
200 mg/5ml x 181.818181 mg = 4.545454 mL
ANS: 4.5 ml
A nurse is preparing to administer gentamicin to a client who weighs 165 lb. The medication reference recommends administering 2 mg/kg IM every 8 hr. How many mg should the nurse plan to administer per dose?
(Round to the nearest whole number.) - ~ANSWER 2.2 lb/kg x 165 lb = 75 kg
2 mg/kg x 75 kg = 150 mg
ANS: 150 mg