For the subgroups of men , at similar BIS40-60 [ 80 ( 72-88 ) % vs 80 ( 70-87 ) % ] , propofol [ 4.2 ( 3.4-5 .3 ) vs 4.4 ( 3.6-5 .4 ) mg kg ( -1 ) h ( -1 ) ] and remifentanil [ 0.19 ( 0.13-0 .25 ) vs 0.18 ( 0.15-0 .23 ) g kg ( -1 ) min ( -1 ) ] consumptions were similar in the N2O vs AIR group , respectively .