Vancomycin dosing

We have traditionally dosed Vancomycin for pre-dialysis levels < 10. However we have started to second guess our practice. With high flux dialyzers, what do you do if the level is 12 or 13. I'm concerned that the dialyzers will remove enough to lower the Vancomycin level to below the desired concentration of 5-10.
Is anyone doing anything different? It would be worth a small trial to see what the 1 hour post levels are, however this is hard to do unless your patients are inpatients.
Jennifer Dykeman-Sharpe
dykje@reg2.health.nb.ca