Final answer:
To calculate the gentamycin dosage for a child weighing 45 pounds, we first convert the weight to kilograms, then calculate the dose in milligrams, and finally determine the volume in milliliters based on the drug's concentration.
Step-by-step explanation:
The subject of this question is Medicine, specifically pharmacology and drug dosage calculations. To calculate the correct dose of gentamycin to administer, we first need to convert the child's weight from pounds to kilograms. Since 1 pound is equivalent to 0.453592 kilograms, we multiply the child's weight by this factor:
45 pounds * 0.453592 kg/pound = 20.41164 kg
Next, using the prescribed dosage of 2.5 mg/kg/dose, we calculate the total dose in milligrams:
2.5 mg/kg * 20.41164 kg = 51.0291 mg/dose
Given the available concentration of gentamycin is 10 mg/mL, we determine how many mL are needed per dose:
51.0291 mg / 10 mg/mL = 5.10291 mL/dose
Rounded to the nearest tenth, the child should receive 5.1 mL of gentamycin per dose.