[Morphine epidural block in lumbosacral pain].

In 60 patients treated in hospital for discopathy the effectiveness of morphine epidural blockade was studied in the control of very strong pain. The patients were divided into 3 groups with 20 cases in each group. Group I received morphine 5 mg with 5 ml of 1% xylocaine. In group II and III the blockade was repeated giving by the double blind method either morphine with normal saline 5 ml followed by xylocaine as the second blockade (in 20 cases) or normal saline injected epidurally in 20 cases. The analgesic effect was assessed measuring the duration of analgesia. After morphine blockades the mean duration of analgesia was 20 hours, and the addition of xylocaine had no effect on it. Following xylocaine blockade the mean time of analgesia was 9.8 hours, and after normal saline injection it was 8.0 hours. The sensory phenomena experienced after morphine by most patients suggest that morphine exerts not only a local but also a central effect, while the similarity of the effects of xylocaine and normal saline suggests an analgesic effect independent of conduction block after epidural injection of these substances.