A way to create concurrent charges that won't double the length of their treatment time?

Is there a way to create concurrent charges that won't double the length of their treatment time? For instance when performing VASO and E-stim together in the clinic it only takes 15 min. However because charges can't be billed concurrently our note says the treatment took 30 min. So now we have to adjust treatment length beyond the time the patient was really in the clinic. It is more accurate from a time standpoint to be able to bill concurrently.