PLACENTAL INTERVILLOUS BLOOD-FLOW MEASURED BY INHALED XE-133 CLEARANCE IN RELATION TO INDUCTION OF EPIDURAL ANALGESIA

A method of determining placental intervillous blood flow (IBF) using an inhaled 133Xe technique is described. The method was used to investigate the effect on IBF of epidural analgesia with an initial dose of 37.5 mg bupivacaine. There was no statistically significant reduction in IBF following the initial dose of bupivacaine in spite of a small but statistically significant reduction in mean blood pressure. There was no significant correlation between the change in mean blood pressure and the percentage change in IBF following epidural block although the single largest percentage reduction in IBF was associated with the largest fall in mean blood pressure. Copyright © 1979, Wiley Blackwell. All rights reserved