To achieve between a 50 % and 90 % probability of no gag response , propofol TCIs were between 2.40 and 4.23 gmL ( that could be achieved with a bolus of 1 mgkg ) when remifentanil TCI was fixed at 1 ngmL , and target propofol TCIs were between 2.15 and 2.88 gmL ( that could be achieved with a bolus of 0.75 mgkg ) when remifentanil TCI was fixed at 2 ngmL .