[Epidural opiate analgesia (EOA), compatibility of opiates with tissue and CSF (author's transl)].

To estimate the compatibility of opiates with tissue we measured the pH of opiate solutions in comparison to local anaesthetics. Piritramide and opium solutions revealed very low pH values (3.96 and 3.38). Two patients, who underwent EOA for the last two and a half three weeks before their death showed, macroscopically and microscopically, no signs of effect on tissue. The examination of the compatibility of opiate solutions and local anaesthetics with CSF showed a deproteinisation of CSF after Piritramide and a rise of opacity after opium. Of the local anaesthetics tested, only Editocaine interferred by crystallizing of the substance. In conclusion, all opiates except piritramide and opium can be used in EOA. In our opinion bupivacaine but not editocaine can be used for spinal anesthesia. All opiates tested can be mixed either with bupivacaine or editocaine.