Intrathecal administration of hyperbaric morphine for the relief of pain in labour.

Thirty healthy women in active labour received an intrathecal injection of morphine 0.5 mg (n = 12) or 1 mg (n = 18) in 7.5% dextrose. Both doses provided excellent analgesia for labour, 93% of patients obtaining at least 50% pain relief. Analgesia began 15-60 min after injection and did not decrease until 6-8 h after injection. Analgesia was satisfactory until distension of the perineum, either by forceps or the infant's head. The intrathecal injection of morphine did not adversely affect the condition of the infant. Eighty per cent of patients developed pruritus; 53%, nausea or vomiting, or both; 43%, urinary retention; and 43%, drowsiness. These side effects were decreased by naloxone, which did not affect the degree of analgesia. There was no significant depression of ventilation in any patient. These results suggest that morphine 0.5 mg or 1 mg, administered intrathecally, effectively decreases the pain of labour, and that i.v. administration of naloxone can alleviate the common side effects.

Continuous infusion epidural analgesia in parturients receiving bupivacaine, chloroprocaine, or lidocaine--maternal, fetal, and neonatal effects.

The effects of epidural analgesia for labor and delivery using a continuous infusion technique on fetal heart rate, uterine activity, maternal blood pressure, Apgar scores, neonatal acid-base status, and the Neurologic and Adaptive Capacity Scoring System were studied in 61 parturients. Group I (n = 23) received initial test and therapeutic doses of 2 and 6 ml of 0.5% bupivacaine followed by an infusion of 0.125% at a rate of 14 ml/hr. Group II (n = 19) received 2 and 6 ml of 2% chloroprocaine followed by an infusion of 0.75% at a rate of 27 ml/hr. Group III (n = 19) received 2 and 6 ml of 1.5% lidocaine followed by an infusion of 0.75% at a rate of 14 ml/hr. None of the three local anesthetics used had any significant effect on baseline fetal heart rate or uterine activity. In cases in which monitoring of fetal heart rate was both technically satisfactory and continuous, late and variable decelerations in fetal heart rate were seen in 10 of 17, 3 of 18, and 2 of 19 of the fetuses in groups I, II, and III, respectively. The incidence was significantly higher in group I than in groups II or III (P less than 0.05). Apgar scores and neonatal acid-base status were equally good in all three groups. Neurologic and adaptive capacity scores did not differ among the three groups of neonates, nor did any of the neonates in the three groups score lower than a control group of 19 neonates whose mothers did not receive any analgesia or medications for labor and delivery.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidural bupivacaine, chloroprocaine, or lidocaine for cesarean section--maternal and neonatal effects.

The effects of epidural anesthesia on maternal blood pressure, newborn Apgar scores, neonatal acid-base status, and the early neonatal neurobehavioral scale (ENNS) were studied in 54 pregnant women undergoing cesarean section. Maternal and neonatal blood levels of the local anesthetics were also determined. Group 1 (n = 16) received 0.75% bupivacaine, group 2 (n = 18) received 3% chloroprocaine, group 3 (n = 11) received 2% lidocaine, and group 4 (n = 9) received 2% lidocaine with 1:200,000 epinephrine. The incidence of maternal hypotension did not differ significantly among the four groups. Fetal outcome as determined by Apgar scores, acid-base status, and neurobehavioral testing was equally good in all four groups. At delivery, the fetal/maternal concentration ratio of bupivacaine was 0.27, that of lidocaine without epinephrine 0.48, and that of lidocaine with epinephrine 0.58. Chloroprocaine was detected in 12 maternal samples, in seven umbilical venous samples, and in six umbilical arterial samples. It is concluded that epidural anesthesia as administered in this study had no adverse effect on the newborn Apgar scores, cord acid-base status, or the ENNS.

Effects of epidural anesthesia during labor on maternal plasma beta-endorphin levels.

Plasma beta-endorphin (beta-EP) was measured in 48 women. Twenty-three were in labor. In 13 of the 23 patients in labor, beta-EP was determined prior to and after complete onset of epidural anesthesia, and in 10 women, who served as controls, prior to and after injection of saline into the epidural space as part of the loss of resistance technique, but before injection of the local anesthetic. Venous blood also was obtained for plasma beta-EP determinations from 10 healthy non-pregnant women and from 15 patients scheduled for elective repeat cesarean section and who were not in labor. Human beta-EP was determined by radioimmunoassay following silicic acid extraction of plasma samples and separation of the beta-EP fraction by gel chromatography. In the 10 non-pregnant volunteers, plasma beta-EP averaged 11.3 +/- 1.5 fmol/ml (mean +/- SE) as compared with 43.7 +/- 6.5 fmol/ml observed in the 15 women with term pregnancies who were not in labor (P less than 0.005). In the 13 patients in labor who underwent epidural anesthesia, plasma beta-EP concentrations decreased (P less than 0.005) from 54.5 +/- 9.0 to 28.2 +/- 3.5 fmol/ml, whereas there was no significant change in plasma beta-EP levels in the 10 controls who averaged 64 +/- 20.5 and 55.8 +/- 13.6 fmol/ml prior to and following saline injection. These data confirm that plasma beta-EP levels are significantly higher in women with term pregnancies in labor than in non-pregnant women and also demonstrate that epidural anesthesia during labor is accompanied by a significant decrease in maternal plasma beta-EP concentrations.

Lack of adverse neonatal neurobehavioral effects of lidocaine.

The effects of epidural anesthesia on the early neonatal neurobehavioral scale (ENNS) following delivery were studied in 22 parturients given 1.5% lidocaine epidural anesthesia during labor and delivery. These results were compared to those obtained in a control group of 17 neonates whose mothers received no analgesics, medications, or local anesthetics for labor or delivery. There was no significant difference in ENNS in the two groups of neonates. Lidocaine as administered in this study has no adverse effects on the early neurobehavioral status of the neonate.

Sympathoadrenal activity, maternal, fetal, and neonatal responses after epidural anesthesia in the preeclamptic patient.

This study confirms that preeclamptic patients have higher plasma levels of catecholamine than those of normal patients. It also demonstrates that epidural analgesia when administered to the preeclamptic patient during labor is followed by a significant reduction in the plasma levels of catecholamines without any adverse effects on maternal blood pressure, uterine activity, fetal heart rate, or the neonate.