Graham J L, King R, McCaughey W
Anaesthesia. 1980 Feb;35(2):158-60. doi: 10.1111/j.1365-2044.1980.tb03796.x.
In postoperative prostatectomy patients, morphine 2 mg in 10 ml 0.9% saline was given epidurally for pain relief and its effectiveness compared with bupivacaine. The duration of analgesia with morphine was approximately double that with bupivacaine. Significant hypotension occurred in approximately 5% of the patients receiving bupivacaine, but was not seen following morphine. These seem to be important advantages in the use of morphine by this route.