higher infusion rates of either narcotic ( fentanyl 2 micrograms x kg-1 x min-1 , 4 micrograms x kg-1 x min-1 ; sufentanil 0.6 micrograms x kg-1 x min-1 , 1.2 micrograms x kg-1 x min-1 ) in the absence of n2o did not produce dysfunction but had no protective effect when n2o was added .
C0015846
fentanyl
C0143993
sufentanil