Question

Order: Vancomycin 12 mg/kg IV every 8 hours for an 11 year old child with a staph infection.

Supply: Vancomycin 500 mg vial to be reconstituted with 10 mL of sterile water. The child weighs 77 lb.

How many ml will you draw from the vial after reconstitution? _____________________

Order: Duricef oral solution 30 mg/kg PO bid for a 7 year old child with tonsillitis. The bottle of medication is labeled 250 mg per 5 mL. The child weighs 44 lb.

How many mL will you give? __________________

Order: Fragmin 80 units/kg SQ every 12 hours for unstable angina. The available dose is 10,000 units per mL.

The patient weighs 140 lb

How many mL will you give? _____________________

Answer 1

Order-1: Given the weight of the child = 77 lb = 77 lb x (0.453592 g /1lb) = 34.93 Kg

the child needs 12 mg/kg Vancomycin in 8 hour

Hence total requirment of Vancomycin in 8 hour = (12 mg/Kg) x 34.93 Kg = 420 mg

500 mg is present in 10 mL of the reconstitution

Hence 420mg of Vancomycin that would be present in the volume of the reconstitution

= (10 mL / 500 mg) x 420 mg = 8.4 mL ((answer)

Order-2:

Given the weight of the child = 44 lb = 44 lb x (0.453592 g /1lb) = 19.96 Kg

the child needs 30 mg/kg Duricef oral solution

Hence total requirment of Duricef oral solution = (30 mg/Kg) x 19.96 Kg = 599 mg

250 mg Duricef is present in 5 mL of the oral solution

Hence 599 mg of the Duricef that would be present in the volume of the oral solution

= (5 mL / 250 mg) x 599 mg = 12 mL (answer)

Order - 3 :

Given the weight of the patient = 140 lb = 140 lb x (0.453592 g /1lb) = 63.5 Kg

the child needs 80 units /kg Fragmin

Hence total requirment of Fragmin = (80 units / Kg) x 63.5 Kg = 5080 units

10000 units are present in 1 mL

Hence 5080 units that would be present in the volume

= (1 mL / 10000 units) x 5080 units = 0.508 mL (answer)