A retrospective study of the anaesthetic records in cardiac surgical patients was undertaken: massive doses of fentanyl were used according to Stanley (29). The rate of drug administration was fentanyl 150 micrograms/kg for induction and 15 to 25 micrograms/kg/hour for maintenance, pancuronium bromide 0,1 mg/kg for induction and 0,015 mg/kg/hour for maintenance. Myocardial oxygen consumption (estimated by rate-pressure-product) during induction period remains constant. The oesophago-rectal temperature gradient is smaller than with other anaesthetic techniques, showing a very good perfusion homogeneity without the need of vasodilatator drugs. The temperature after-drop in the post bypass period is also reduced (less than 1,2 degrees C). The incidence of hemodynamic and rhythmic disturbances during operations and during the first post-operative day is lowered. Delayed respiratory autonomy appears to be the major drawback of this method (group 1: 25,30 h +/- 7,30 h; 30,20 h +/- 12,25 h; group 3: 21,15 h +/- 6,25 h).