[A study on spinal anesthesia for cesarean section--with special reference to left uterus displacement device (LUDD)]

In this study, 303 cases of cesarean section by spinal anesthesia with the application of LUDD were studied to find the relationships between induction to delivery time (I-D time) and Apgar score (Ap-S), level of anesthesia and changes in maternal circulation and also to observe changes in feto-maternal acid base status, feto-maternal CO2 metabolism monitored with an Anesthesia & Brain activity Monitor (ABM) and post anesthesia complications.

The use of LUDD as a prophylactic measure to prevent maternal hypotension was very effective. The elevation of anesthesia level always involved the risk of maternal hypotension even when the LUDD was used. A slight drop in blood pressure during the short period before the infant was delivered did not adversely affect the AP-S, but prolonged I-D time did affect the clinical condition of the infant and probably promoted acidosis. Administration of 100% O2 induced mild maternal acidosis but, for the short period before delivery, the fetal oxygenation and CO2 metabolism were smooth with reduced acidosis. Since there was a close correlation between maternal PECO2 and PaCO2 and PCO2 of the maternal blood (MA, MV) and umbilical blood (UA, UV) were also correlated, the continuous monitoring of PECO2 with an ABM was deemed to be very useful in anesthesia for cesarean section. In the 303 cases studied, a case of headache was the only post-anesthesia complication.