Tissue reaction of morphine applied to the epidural space of dogs.

Epidural morphine has found increasing popularity in clinical trials for the relief of chronic and postoperative pain relief. This study was conducted to determine if there was any adverse tissue reaction when morphine was applied to the epidural space of dogs. Sixteen dogs were given 0.07 mg X kg-1 of morphine in a volume of 2 cc of normal saline into the epidural space. Gross and microscopic studies of the epidural space, dura, and spinal cord did not show any adverse tissue reaction.