Module 9. Relationship between volume of distribution and clearance. Effect of volume of distribution (only) changes.

Objectives

Having completed this exercise and based on pharmacokinetic constants and data, students should be able to:

Significance

S.L. Green et. al.: Effects of hypoxia and azotaemia on the pharmacokinetics of amikacin in neonatal foals. Equine Veterinary J. 24(6), 475-479, 1992.

Gram-negative septicemia in the newborn foal is a major cause of neonatal mortality. Aminoglycoside antibiotics are an excellent choice for treatment or prevention of gram negative sepsis. However, aminoglycoside pharmacokinetics are different in foals than in adult horses. Consequently, it is important to make appropriate dose and interval corrections in order to provide safe and effective therapy. Especially in foals, it is possible to produce aminoglycoside toxicity without producing bactericidal aminoglycoside therapy!

Exercise

Download amikacinvolume.xlsx, the spreadsheet for this exercise. Depending on your settings, you may have to "enable editing" in order to make the changes suggested by the exercise.

Pharmacokinetic variables on the worksheet are preset for amikacin in horses.

Target concentrations

Manipulate the dosage

Inspect

Calculated values

Steady-State Concentrations (for repeated doses during therapy).

Graphs

Assess