vancomycin elimination rate constant = k =
= ((0.00083 * (creatinine clearance)) + 0.0044)
steady state Vd varies from 0.72 - 0.90 liter/kg.
serum clearance of vancomycin =
= (3.66 + (0.689 * (creatinine clearance)))
vancomycin dosing in renal failure that will maintain serum concentrations of 30 mg/L at peak and 7.5 mg/L at trough:
(1) initial dose 25 mg/kg = (25 * (body weight in pounds) / 2.2)
(2) maintenance dose 19 mg/kg given at calculated dosing interval (below) = (19 * (body weight in pounds) / 2.2)
calculated dosing interval =
= ((normal dosing interval) * (normal serum clearance of vancomycin) / (serum clearance of vancomycin in patient)) =
= ((0.5 days) * (86 mL/min) / (3.66 + (0.689 * (creatinine clearance))))
NOTE:
(1) Body weight is the actual body weight, not the ideal body weight.
(2) Method uses standard loading and maintenance dose, with adjustment made in dosing interval.
(3) The "normal dosing interval" of 0.5 days is with a creatinine clearance of 120 mL/min, which gives a serum clearance of 86 mL/min. If the creatinine clearance is 100 mL/min, the "normal dosing interval" is 0.6 days and the serum clearance is 72.6 mL/min.