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The frequency of marked fetal bradycardia (FB) during selective lumbar epidural anaesthesia with 0.25% or 0.5% bupivacaine (Marcain, Bofors) without adrenaline in doses of 5 ml to 8 ml is reported. 35 patients were monitored by means of the Hewlett-Packard Cardiotocograph with Hon's spiral scalp electrode and a transcervical catheter connected to a Hewlett-Packard (1280 B/C) physiological pressure transducer. Only patients with a normal cardiotocogram (CTG) before anaesthesia are included. During the second stage pathological fetal heart rate (FHR) patterns and technical artefacts are common, therefore the CTGs recorded in this period were not considered. In the 35 patients the total time of intrauterine monitoring was 119 hours. During this period 125 doses of 0.25% and 23 doses of 0.5% bupivacaine were given. In 33 parturients the FHR changes observed were insignificant. In one case a period of marked FB was seen. One parturient developed acute hypotension with a synchronous FB while lying in the supine position. It is concluded that continuous lumbar epidural anaesthesia with bupivacaine without adrenaline does not precipitate FB during the first stage when care is taken to avoid maternal hypotension.

Epidural anaesthesia was given to nine parturients who were considered candidates for delivery by caesarena section due to prolonged exhaustive labour. Upon pain relief and oxytocin infucion guided by cardiotocography, vaginal delivery took place. Delivery was spontaneous in seven cases, two were instrumentally delivered. It is concluded that an efficient epidural block tends to restore uterine contractility by reducing the inhibitory influences exerted by adrenergic mechanisms and unfavourable changes in the acid-base balance.

Two groups of six parturients each have been compared. One group received centrally acting analgesics, sedatives and intermittent nitrous oxide and the other group was given epidural anaesthesia. The serum free fatty acid (FFA) concentrations of the parturients in the former group increased steadily during labour, attaining peak values between 1050 and 1750 mumol/l at delivery. In parturients belonging to the epidural group, the serum FFA concentrations remained level or even fell towards the time of delivery. It is suggested that the increase in serum FFA reflects a stress induced adrenergic lipolysis which may be used to assiss the various methods for obstetrical analgesia. It is concluded that epidural anaesthesia is superior to the conventional methods of pain relief. Analyses of blood sampled from the unbilical veins show that the concentrations of FFA in the blood of the newborns do not reflect the corresponding maternal values. Thus, epidural anaesthesia does not seem to deprive the fetus of FFA during labour since the factor limiting its transfer appears to be independent of the concentration gradient over the placental membrane.

The incidence and magnitude of retinal haemorrhages in a group of neonates delivered spontaneously (n = 50), whose mothers received epidural analgesia during labour, has been compared to those of a spontaneously delivered control group (n = 50) who received conventional analgesia. The second stage of labour was significantly longer in the epidural group (P less than 0.001), which contained a higher number of primiparas than did their controls. Still, a lower incidence of retinal haemorrhages was noted in the epidural group (P less than 0.01). The study indicates that epidural analgesia offers a certain degree of protection against perinatal retinal haemorrhages in the spontaneously delivered neonate.

The results of 204 cases of regional analgesia by means of continuous epidural block during labour and delivery are reported. The frequency of instrummental intervention using forceps or the vacuum extractor is low, less than 15% for primi- and multi-gravidas combined, although pathological conditions were recognized prior to blockade in almost one-third of the parturients. Moreover, the frequency of emergency Caesarean section has dropped significantly since epidural anaesthesia was introduced into the clinic. The 1 min Apgar scores of babies born to mothers given epidural anaesthesia are similar to those of babies born to mothers receiving conventional analgesic agents. The amount of blood lost by mothers given epidural anaesthesia was, on average, 15% less than in a control group. It is concluded that the essential feature of our technique of administering continuous regional analgesia is a selective block of small pain fibres with the deep tactile sensations largely intact, and the motor pathways virtually unaffected. This has been achieved using small doses of bupivacaine 0.25% concentration and meticulous observation of the individual patient.