Trilogy 100 & Bi-Pap users on oxygen

How much oxygen do you use when on the Trilogy 100 and Bi-pap at night? I am on 3 liters during the day sitting at 92 to 94 and sleep turned down to 2 1/2 liters not on a machine. Would be interested to hear if you use more oxygen when sleeping on the machines. Do you lose a certain amount oxygen on a machine due to the leak and the pressures?

Thanks!