[Clinical study on total intravenous anesthesia with droperidol, fentanyl and ketamine--11. Effect on epidural pressure].

We have developed a new method of total intravenous anesthesia using ketamine, fentanyl and droperidol (NLA-FK). There are many reports describing a significant increase in cerebrospinal fluid pressure (CSFP) during ketamine administration, but little is known about changes in CSFP during NLA-FK. As epidural pressure (EP) is considered as a good index for CSFP, we measured it in 12 patients under either NLA-FK or isoflurane anesthesia, who underwent gastrectomy. In the NLA-FK group the EP increased significantly by 26% at the induction of anesthesia as compared with the preinduction level, and it decreased to the preinduction level 30 minutes after the induction. Thereafter the pressure was not appreciably changed. In the isoflurane group EP significantly decreased by 16% at induction, but the pressure significantly increased by 29% 30 minutes after the induction as compared with the preinduction level. The change was similar to that of the NLA-FK group. Although the increase in the EP during the induction of NLA-FK is significant, it is considered to be within normal ranges. However, further detailed clinical study is needed to attenuate the significant increase in the EP during the induction of NLA-FK.