[Comparative study of sequential analgesic anesthesia (SAA) with continuous-infusion analgesia by fentanyl].

A group of elderly (mean age: 75 years) patients undergoing a prothetic on the hip under analgesic anaesthesia using fentanyl by continuous infusion (7 micrograms.kg.h(-1)) was compared with a similar group receiving sequential analgesic anaesthesia using fentanyl (25 micrograms.kg as a bolus then 7 micrograms.kg(-1).2030mins(-1)). Comparison of the results obtained revealed a variation in mean cardiocirculatory parameters which was less marked in the group receiving fentanyl by infusion than in the group receiving it sequentially. The higher doses used in the sequential analgesia group led in the majority of cases to severe respiratory depression requiring its reversal by an antagonist or postoperative ventilatory assistance, whilst the use of fentanyl by infusion made it possible to reduce total doses of the drug and ensure adequate spontaneous respiration at the end of the operation.