Criteria for nephrotoxicity:
(1) increase in serum creatinine after initiation of vancomycin therapy
(2) (increase by >= 0.5 mg/dL) OR (increase by >= 50%), whichever is greater
Risk factors:
(1) vancomycin trough level in mg/L (ng/mL), with risk increased if the trough is >= 15 mg/L
(2) admission to the ICU
The percentage of patients developing nephrotoxicity are shown in Figure 3. The lines can be approximated by the following:
percentage of patients not in the ICU who develop nephrotoxicity =
= (0.04848 * ((trough level)^2)) - (0.2029 * (trough level)) + 2.331
percentage of patients in the ICU who develop nephrotoxicity =
= (0.04386 * ((trough level)^2)) + (0.8193 * (trough level)) + 5.343
An additional risk factor influencing the time to renal injury was body weight, with shorter time interval if the body weight was >= 101 kg.
where:
• It wouild be interesting to see if body weight persists as a risk factor if lean body weight was used for dosing rather than actual body weight.
