Effect of Extradural Analgesia Using Bupivacaine and 2-Chloroprocaine on Intervillous Blood Flow During Normal Labour

Abstract

The effect of lumbar extradural analgmig on intervillous blood flow (IBF) during labour was studied in 26 healthy parturients using an i. v. bolus injection of xenon-133. There was a 19% decrease (n.s.) in mean IBF in six parturients (non-extradural control group). Mean IBF increased by 37.5% when 0.25% bupivacaine 10 ml was used and by 35.2% when 2% 2-chloroprocaine 10 ml was used (n.».). When the two extradural groups were combined, the mean difference between IBFi and IBF2 was 45+ 112mlmin"' dl" 1. This increase is statistically significant (P< 0.05). The improvement in IBF after extradural block was considered to be a result of the decreased uterine vascular resistance, as no significant changes were observed in arterial pressure, utenne activity or uterine tone.

Intervillous Blood Flow During Caesarean Section With Prophylactic Ephedrine and Epidural Anaesthesia

“…The concentrations of local anaesthetics used in this kind of study have, however, been many times higher than those blood concentrations found during clinical use of epidural anaesthesia. The use of different local anaesthetics for epidural analgesia does not seem to influence IBF (20). The use of chloroprocaine and lidocaine in our studies was also evenly distributed between the ephedrine and the control groups (4:5 and 4:5, respectively).…”

Epidural analgesia‐a cause of transient impairment of the utero‐placental circulation?

“…Using the 133 Xe washout method, Jouppila et al (1978) found a slight (but non‐significant) reduction in intervillous blood flow and no change in myometrial blood flow. Using a similar technique, Hollmen et al (1982) studied the effect of epidural analgesia in labour and noticed an increase in intervillous blood flow which they attributed to a decrease in uterine vascular resistance. In animal experiments (Wallis et al 1976), no changes in placental blood flow after epidural anaesthesia were seen, provided blood pressure remained stable.…”

Maternal and fetal endocrine stress response at vaginal delivery with and without an epidural block

“…Conas well as arterial umbilical cord blood CA versely, epidural block is supposed to be benefihave been observed after vaginal delivery, and cial to the fetus since low maternal levels of CA especially in association with fetal acidosis [11, are associated with increased uterine blood flow 18]. [5,9]. In addition, the preserved ability of the fetus to respond to stress during labor after Catecholamine concentrations in venous cord epidural block ought to be a prerequisite for a blood originate mainly from fetus since there normal adaptation after birth.…”