Plasma corticosteroids, free fatty acids, insulin and glucose in maternal blood during delivery

Insulin and glucose requirements during the first stage of labor in insulin-dependent diabetic women

Studies utilizing glucose-controlled insulin infusion systems were undertaken to more accurately define the glucose and insulin requirements during the first stage of labor induced by oxytocin in 12 insulin-dependent diabetic women in whom normoglycemia had been maintained before delivery. Insulin requirements decreased to zero during active stage 1 labor, while the glucose infusion rate necessary to maintain a blood glucose level of 70 to 90 mg/dl (or 3.9 to 5.0 mmol/liter) was constant at 2.55 mg/kg per minute. The findings were confirmed in 40 additional studies of oxytocin-induced labor. Studies of six women undergoing spontaneous labor and one nonpregnant woman receiving oxytocin confirmed that the decrement in the insulin requirement during stage 1 labor was not influenced by oxytocin infusion. The changes occurred regardless of whether epidural anesthesia was employed. Insulin requirements returned during the second stage of labor. Active stage 1 labor in diabetic women thus appears to be associated with a predictable decrease in the need for insulin and a constant glucose requirement.

Arachidonic acid and other free fatty acid changes during abortion induced by prostaglandin F2alpha

Serum free fatty acids (FFA's) were measured after intra-amniotic injection of prostaglandin F2alpha (PGF2alpha) for the induction of abortion in eight healthy women in the midtrimester of pregnancy. The total FFA levels increased in all cases during the period between PGF2alpha administration and abortion. This lipolysis most likely is secondary to the effect of the catecholamines as indicated by the temporal relationship between increased plasma and urine catecholamine and serum FFA levels. The percentage of arachidonic acid in the total amount of FFA's decreased after administration of PGF2alpha. This proportional decrease in arachidonic acid (p less than 0.05) may be due to selective utilization for the production of endogenous prostaglandins.

Segmental epidural analgesia and urinary excretion of catecholamines during labour

Urinary excretion of catecholamines was determined separately during the first stage of labour and during the period from the beginning of the second stage until 1/2 h after delivery in 16 healthy mothers, whose labours were induced at term. Seven mothers were given segmental epidural analgesia, at the height of TH10-12, to achieve complete pain relief during the first stages of labour. The remaining parturients served as controls. During the first stage of labour the urinary excretion rate of catecholamines was at the normal nongravid rest level in both groups. During the second stage, and 1/2 h after the delivery, the amount of urinary catecholamines increased significantly in both groups. The latter values corresponded to the amounts of catecholamines excreted during heavy physicial work.

Epidural anaesthesia as an alternative to caesarean section in the treatment of prolonged, exhaustive labour

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.

Obstetrical analgesia assessed by free fatty acid mobilisation

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.