vancomycin rate of administration on dialysis

I've discovered our nurses are administering vancomycin over the last hour of dialysis and have been doing so for a while as patients refuse to stay after dialysis. Policy dictates vanco be given at a rate of 10mg/min. We have had no incidences of red man's syndrome or other untoward effects. Considering that our patients are undergoing simultaneous high flux dialysis and will be losing a certain percentage of the drug during administration, what are the concerns? Does anyone deviate from the standard 10mg/min?