A new neurologic and adaptive capacity scoring system for evaluating obstetric medications in full-term newborns

Comparison of maternal and neonatal outcomes with epidural bupivacaine plus fentanyl and ropivacaine plus fentanyl for labor analgesia

BACKGROUND

Several studies have been performed to find a safe method of labor analgesia with minimal side effects and toxicity in mother and fetus. We aimed to compare the efficacy and side effects of epidural bupivacaine plus fentanyl and ropivacaine plus fentanyl at low concentrations.

METHOD

Forty ASA I-II parturients' were included in this prospective, double-blind, trial and randomized to receive either bupivacaine or ropivacaine for labor analgesia. Analgesia was initiated with 8 mL of 0.125% solution plus fentanyl 50 microg and maintained with a continuous infusion of 0.0625% solution with fentanyl 2 microg/mL.

RESULTS

There were no differences in pain scores, total dose of local anesthetics used, sensory or motor blockade, labor duration, mode of delivery, side effects, patient satisfaction, or neonatal outcome between the two local anesthetics at these dosages, but at the end of the second stage and delivery, adequate analgesia quality could not be ensured.

CONCLUSION

We found no major advantage of continuous epidural infusion of ropivacaine 0.0625% plus fentanyl 2 microg/mL over bupivacaine 0.0625% plus fentanyl 2 microg/mL for labor analgesia. We believe that different methods or dosages may be tried in order to improve comfort at the second stage of labor and the delivery.

Epidural analgesia during labor and delivery: effects on the initiation and continuation of effective breastfeeding

This prospective cohort study examined the association between epidural analgesia during labor and delivery, infant neurobehavioral status, and the initiation and continuation of effective breastfeeding. Healthy, term infants delivered vaginally by mothers who received epidural analgesia (n = 52) or no analgesia (n = 63) during labor and delivery were assessed at 8 to 12 hours postpartum, followed by a telephone interview with the mothers at 4 weeks postpartum. There was no significant difference between the epidural analgesia and no-analgesia groups in breastfeeding effectiveness or infant neurobehavioral status at 8 to 12 hours or in the proportion of mothers continuing to breastfeed at 4 weeks. Therefore, epidural analgesia did not appear to inhibit effective breastfeeding. There was a positive correlation between infant neurobehavioral status and breastfeeding effectiveness (Spearman rho = 0.48, P = .01), suggesting that neurobehavioral assessment may prove beneficial in identifying infants at greater risk for breastfeeding difficulties.

Epidural analgesia for childbirth: effects of newer techniques on neonatal outcome

New low-dose, local anesthetic-opioid combinations, combined spinal epidural analgesia, and new anesthetic drugs, such as ropivacaine and levobupivacaine, have modified the anesthetic practice in obstetric labor analgesia. These new analgesic techniques have less or no neonatal effects when compared with traditional epidural labor analgesia. They also have less effect on mode of delivery, which may in turn affect neonatal outcome. The use of very diluted or low concentrations of local anesthetic solutions may reduce their placental passage and thus the possible subtle neonatal effects. Small doses of epidural or spinal opioids alone or combined with low doses of local anesthetics does not affect the well-being of the neonate at birth. When considering the neonatal outcome, combined spinal epidural analgesia is as well tolerated as low-dose epidural analgesia. Transient fetal heart rate changes have been described immediately after the administration of intrathecal or epidural opioids. Maternal hypotension may also occur at the onset of epidural analgesia. Whether the occurrence of transient fetal heart rate changes or maternal hypotension immediately after the epidural block may influence the neonatal outcome at birth needs verification.

Neurobehavioral functioning and breastfeeding behavior in the newborn

OBJECTIVE

To determine whether central nervous system functioning has an effect on the normal, term infant's ability to breastfeed in the first day following birth.

DESIGN

Breastfeeding behaviors and neurobehaviors were evaluated at birth and at 24 hrs of age in two groups of neonates. One group of neonates was born to mothers who received epidural analgesia during labor, and one group was born to mothers who received no pain medication. Breastfeeding behavior was evaluated using the Preterm Infant Breastfeeding Behavior Scale, and the infant's neurobehaviors were evaluated using the Neurologic and Adaptive Capacity Score.

PARTICIPANTS

Fifty-six breastfeeding mother-newborn dyads. All mothers were healthy multiparae who gave birth vaginally to normal, full-term, healthy newborns.

MAIN OUTCOME MEASURES

Newborns were observed for rooting, latch-on, sucking, swallowing, activity state, and neurobehavior.

RESULT

Analysis of the data indicated that the higher the infant scored in relation to neurobehavioral functioning, the higher the infant scored on breast-feeding behaviors.

CONCLUSION

When determining physiologically what is important for the infant to successfully latch on and feed, it appears that an intact and functioning central nervous system may be one of the crucial elements.

Different pharmacokinetics of tramadol in mothers treated for labour pain and in their neonates

OBJECTIVE

The aim of the present study was to investigate the pharmacokinetic profile of tramadol hydrochloride in neonates, born from mothers who underwent analgesia with tramadol for the relief of labour pain.

METHODS

Intramuscular tramadol (100--250 mg) was administered to 22 mothers giving birth who requested pain relief. At the time of birth (1.5--6.0 h after last tramadol dose), maternal and umbilical blood samples were taken. Another venous blood sample was drawn from each neonate, and at the same time from its mother, at 1, 2, 3, 6 or 12 h post-partum, providing the data for a population pharmacokinetic evaluation of tramadol and its metabolite M1. Routine APGAR scores and a standard neurological and adaptive capacity test were considered for evaluation of the effect of tramadol on the neonates.

RESULTS

Serum tramadol concentrations at the time of birth (t(0)) were 243+/-102 ng/ml (mean+/-SD, umbilical vein), 258+/-103 ng/ml (umbilical artery) and 250+/-113 ng/ml (maternal vein). Serum M1 concentrations were 52+/-27 ng/ml (umbilical vein), 47+/-24 ng/ml (umbilical artery) and 56+/-21 ng/ml (maternal vein). The two-compartment type elimination profiles during the first 12 h post-partum for neonates (and mothers, respectively) were characterised by terminal t(1/2) (tramadol)=7.0 (7.2) h and t(1/2) (metabolite M1)=85.0 (5.5) h.

CONCLUSION

The intramuscular application of tramadol in birth-giving mothers almost freely reaches the neonate, confirming a high degree of placental permeability. The neonates already possess the complete hepatic capacity for the metabolism of tramadol into its active metabolite. However, the renal elimination of the active tramadol metabolite M1 is delayed, in line with the slow maturation process of renal function in neonates. Despite this difference in pharmacokinetics between neonates and adults, the intramuscular application of tramadol at the recommended dosage range during delivery appears to effective in the relief of labour pain.

Motor block during epidural infusions for nulliparous women in labour: a randomized double-blind study of plain bupivacaine and low dose bupivacaine with fentanyl

Sixty nulliparous women received epidural infusions in labour of either 0.125% plain bupivacaine or 0.0625% bupivacaine containing 2.5 mcg/ml fentanyl both starting at 12 ml/h and titrated to maintain a sensory block to T10. Those women who received low dose bupivacaine with fentanyl took significantly longer to reach full cervical dilation (P < 0.05). There was no statistical difference between the groups in the number of additional epidural bolus doses required during the infusions. Of the women receiving low dose bupivacaine with fentanyl, 77% required one or no additional top-up doses compared to 87% in the plain bupivacaine group. There was no reduction in the incidence of perineal pain in the group who received fentanyl. Significantly more women who received 0.125% bupivacaine had motor block after 2 h of the infusion (P < 0.05). The mode of delivery was similar in the two groups as was the satisfaction with epidural analgesia in both the first and second stages of labour and with labour overall. There were no significant differences in Apgar scores, umbilical cord blood pH levels or neurologic and adaptive capacity scores at 2 or 24 h. There was no significant difference in the incidence of symptoms 24 h after delivery.

Epidural ropivacaine 1% with and without sufentanil addition for Caesarean section

BACKGROUND

So far only ropivacaine concentrations of 0.5 and 0.75% have been used for Caesarean section. This prospective double-blind trial evaluated the anaesthetic quality of ropivacaine 1% with and without sufentanil addition.

METHODS

Three groups of patients (n=20 each) scheduled for an elective Caesarean section were studied. The patients received initially 120 mg ropivacaine, or 120 mg ropivacaine plus 10 microg or 20 microg sufentanil. Additional epidural ropivacaine was injected if necessary. Primary outcome parameter was time to achieve sensory block at T4. Moreover, pain intensity at delivery (visual analogue scale, VAS), incidence of maternal side-effects (hypotension, bradycardia, nausea, vomiting, shivering, pruritus), and neonatal outcome (Apgar score, neurologic and adaptive capacity score, umbilical cord blood-gas values) were recorded.

RESULTS

The onset time for the sensory block was not significantly different among the groups. Also, VAS scores at delivery did not differ significantly between the plain ropivacaine 1% group (18 +/- 29 mm), the 10-microg sufentanil group (1 +/- 5 mm), and the 20-microg sufentanil group (6 +/- 18 mm). The total dose of ropivacaine was significantly higher in the plain ropivacaine 1% group (145 +/- 19 mg) compared to the patients receiving additional 10 microg sufentanil (130 +/- 15 mg, P = 0.02) or 20 microg sufentanil (129 +/- 16 mg, P = 0.01). The incidence of maternal side-effects and neonatal outcome were similar in all groups.

CONCLUSION

Ropivacaine 1% alone provided sufficient analgesia. Sufentanil addition did not significantly improve the quality of epidural anaesthesia with ropivacaine 1.0% for Caesarean section.

The Amiel-Tison neurological assessment at term: Conceptual and methodological continuity in the course of follow-up

The Amiel-Tison Neurological Assessment at Term (ATNAT) is part of a set of three different instruments based on a neuro-maturative framework. By sharing a same methodology and a similar scoring system, the use of these three assessments prevents any rupture in the course of high risk children follow-up from 32 weeks post-conception to 6 years of age. The ATNAT which takes 5 minutes to administer may be used in clinical setting as well as in research. Clustering of severe to mild neuro-cranial signs in the neonatal period permits identification of children who could benefit from early intervention.

Meperidine for dystocia during the first stage of labor: A randomized controlled trial

OBJECTIVE

This study was undertaken to evaluate whether the administration of meperidine decreases the length of labor in patients with a diagnosis of dystocia during the first stage of labor.

STUDY DESIGN

Women with term singleton pregnancies who received a diagnosis of dystocia and required an active management of labor were randomly assigned to receive either 100 mg of meperidine or placebo. The primary outcome measure was length of labor.

RESULTS

Four hundred seven pregnant women were included. There were no significant statistical differences between meperidine and placebo groups in length of labor and operative delivery rates such as forceps and cesarean section by intention-to-treat analysis. Low Apgar scores, umbilical artery acidosis, and admission to neonatal care units were increased in the meperidine group.

CONCLUSION

Because of the absence of any benefits in patients with dystocia in labor and the presence of harmful effects on neonatal outcomes, meperidine should not be used during labor for this specific indication.

Effects on the fetus and newborn of maternal analgesia and anesthesia: a review

PURPOSE

To review the effects of maternal anesthesia and analgesia on the fetus and newborn.

METHODS

An on-line computerized search of Medline, Embase, and the Cochrane Collaboration via PubMed was conducted. English language articles were selected. The bibliographies of relevant articles and additional material from other published sources were retrieved and reviewed.

PRINCIPAL FINDINGS

No one test clearly separates the effects on the fetus/newborn, if any, of maternally administered medication during labour and delivery, or during surgery for non-obstetric indications. Supposition in this regard is limited in part by methodology previously used to study the transplacental passage of various drugs. This work needs to be repeated using a human model. Routine maternal supplemental oxygen administration is being questioned in light of research showing that free radical generation and oxidative stress are implicated as the underlying mechanisms in several neonatal conditions. Maternal hypotension is associated with neonatal acidemia and base excess correlates with neonatal outcome. Common postpartum analgesics transfer minimally into breast milk. Maternal or fetal surgery conducted during pregnancy necessitates modification of both anesthetic and surgical approaches. The key to resuscitation of the fetus is resuscitation of the mother: intra-uterine maneuvers, including perimortem Cesarean section, aim to reverse treatable causes of fetal asphyxia, restore fetal oxygenation, and correct fetal acidosis.

CONCLUSIONS

The well-being of the infant is a major criterion for evaluating the anesthetic management of pregnant women. Many tools exist to assist with this determination for the fetus, whereas few are available to evaluate the newborn.

Douleur et analgésie obstétricales

GOAL AND METHODS

Labor pain is of major concern since most parturients experience significant pain of extremely severe intensity for many. The purpose of this review was to provide an overview of the mechanisms and pathways of labor pain (including new insights on integration of the nociceptive signal) and to emphasize the need of effective labor pain relief.

RESULTS

Labor pain can have deleterious effects on the mother, on the fetus and on labor outcome itself. Among the current methods of obstetric analgesia, regional analgesia (the most widespread technique being epidural analgesia) offers the best effectiveness/safety ratio thanks to pharmacological innovations. Systemic analgesia (parenteral opioids, nonopioid painkillers and inhaled anesthetic agents) provides an alternative to regional analgesia but remains less effective and more hazardous. Non-drug approaches (namely psychoprophylaxis and physical methods) may be effective when used with epidural analgesia but are often not potent enough when used alone.

CONCLUSION

Despite its complex pathophysiology, labor pain can be efficiently managed. Thanks to multidisciplinary care, obstetric analgesia (mainly epidural analgesia) prevents deleterious effects of labor pain on the mother and fetus.

The effect of ultra low dose epidural analgesia on newborn breastfeeding behaviors

OBJECTIVE

To determine whether a difference in breastfeeding behaviors could be observed between newborns whose mothers received epidural analgesia for labor pain relief and those newborns whose mothers received no pain medication in labor.

DESIGN

There were two groups of neonates in this study. One group was born to mothers who received epidural analgesia, and one group was born to mothers who received no pain medication for labor. Both groups were observed for initial breastfeeding behaviors using the Premature Infant Breastfeeding Behavior Scale following birth and at 24 hours. Central nervous system functioning in the newborn was measured with the Neurologic and Adaptive Capacity Score at 2 and 24 hours of age.

SETTING

A large tertiary hospital in northeast Ohio.

PARTICIPANTS

Fifty-six breastfeeding mother-newborn dyads. All mothers were healthy multiparae who gave birth vaginally to normal, full-term, healthy newborns.

MAIN OUTCOME MEASURES

Newborns were observed for rooting, latch on, sucking, swallowing, activity state, and neurobehavior.

RESULTS

There were no statistically significant differences in breastfeeding behaviors at birth or at 24 hours of age.

CONCLUSION

A possible cause for the lack of significant results may have been the ultra low dose of bupivacaine and fentanyl used in this sample.

Update of the Amiel-Tison neurologic assessment for the term neonate or at 40 weeks corrected age

Amiel-Tison neurologic assessment at term has recently been updated for clinical application. Experience in this field, in addition to a better understanding of pathophysiologic characteristics of the immature brain, has taught us that an increased precision in assessing central nervous system function in the neonate is compatible with a simplification of the clinical instrument. The complete procedure takes approximately 5 minutes. A simple 0, 1, and 2 scoring system is proposed. Because this coding system is not quantitative, any computation of quotient or total score is inappropriate. Rather, a final synthesis based on clusters of signs and symptoms is advisable. A distinct final synthesis is proposed for term newborn infants in the first week of life and for preterm neonates at approximately 40 weeks of age corrected. Clinical profiles emerging from repeated assessments in the term newborn and early clinical findings indicating a brain damage of prenatal origin are described. Interrater reliability has been proved to be more than satisfactory. Such an assessment is useful for any newborn infant in maternity wards or for any preterm infant approximately 40 weeks of age, with or without abnormal imaging findings.

Addition of epinephrine to epidural ropivacaine during labour – effects on onset and duration of action, efficacy, and systemic absorption of ropivacaine

Addition of epinephrine to epidural anaesthetic solutions may enhance efficacy and duration of analgesia. We postulated that addition of epinephrine 5 microg.mL(-1) to epidural ropivacaine would improve efficacy, decrease systemic absorption and reduce neonatal effects. Twenty-one multiparous women were studied. An initial dose of ropivacaine 30 mg followed by an infusion of ropivacaine 10 mg.h(-1) was given via a lumbar epidural catheter. According to random allocation, epinephrine 5 microg.mL(-1) was added to ropivacaine. Ropivacaine concentrations were measured in maternal venous plasma after one hour of infusion and in both umbilical venous and maternal plasma at delivery. Neonatal neurologic and adaptive capacity score (NACS) tests were performed at 2 and 24 h postpartum. All women delivered vaginally. The groups had similar ropivacaine dose requirements, epidural-delivery intervals and satisfaction scores. Bromage scores for motor block were greater in the epinephrine group (2; range: 1-3) than controls (1; range: 0-2). Mean plasma ropivacaine concentrations (+/-SD) were less in the epinephrine group (0.17 +/- 0.05 mg.L(-1), n = 10) than controls (0.31 +/- 0.14 mg.L(-1), n = 11; P < 0.05) after one h of infusion but not at delivery. UV ropivacaine concentrations and NACS scores were similar in the two groups. The addition of epinephrine to ropivacaine decreases maternal plasma concentrations after one h of epidural infusion but also increases motor block.

The primary action of epidural fentanyl after cesarean delivery is via a spinal mechanism

We tested the hypotheses that the primary mechanism of action of epidural fentanyl after cesarean delivery is spinal and that very small dose epidural bupivacaine with epinephrine enhances this effect. After elective cesarean delivery, 100 parturients were randomized in a double-blinded design to four groups. Group I and II patients received a continuous 12 mL/h epidural infusion of bupivacaine 0.015% with epinephrine 1 microg/mL for 48 h and Groups III and IV received a 12 mL/h saline epidural infusion instead. Fentanyl 20 microg/mL was administered via a patient-controlled analgesia device either into the epidural infusion (Groups I and IV) or IV (Groups II and III). When compared to patients receiving epidural fentanyl, those receiving IV fentanyl required larger mean infused and total dose of fentanyl (P < 0.0001), reported more pain (P < 0.001), and had a more frequent incidence of excessive sedation (P < 0.01), nausea (P < 0.01), and vomiting (P < 0.01). Plasma concentrations of fentanyl were larger for Group II and III than for Groups I and IV (P < 0.001) at 24 and 48 h. Our results support the hypothesis that the primary mechanism of analgesia of epidural fentanyl after cesarean delivery is spinal. Our data also show that the total required dose of epidural, but not IV, fentanyl is reduced by very small dose epidural bupivacaine and epinephrine (Group I versus Group IV, P < 0.02 and Group II vs Group III, not significant).

IMPLICATIONS

Fentanyl administered epidurally to parturients after cesarean delivery has a primarily spinal mechanism of action and this effect is enhanced by very small dose epidural bupivacaine and epinephrine.

Epidural ropivacaine hydrochloride during labour: protein binding, placental transfer and neonatal outcome

This study was undertaken: (i) to quantify the effects of labour and epidural analgesia on plasma alpha1-acid glycoprotein concentration, (ii) to examine the effects of changes in plasma alpha1-acid glycoprotein concentration on plasma protein binding and placental transfer of ropivacaine, and (iii) to examine the association between umbilical venous ropivacaine concentration and neurobehavioural function in the neonate. Multiparous patients undergoing induction of labour received a continuous epidural infusion of 0.1% ropivacaine following an epidural bolus. A significant association was demonstrated between maternal plasma alpha1-acid glycoprotein concentration and 1/free fraction of ropivacaine 60 min after starting ropivacaine administration (r(2) = 0.77) but not at delivery. No significant correlation was demonstrable between maternal unbound ropivacaine concentration and either neonatal (cord) ropivacaine concentration or UV/MV (a measure of placental transfer). Thirty minutes after delivery, 9/10 neonates had neurological and adaptive capacity scores < 35, whereas only three infants had scores < 35 at 2 h. All scores exceeded 35 16 h after delivery. No association between mean (SD) umbilical venous ropivacaine concentration [0.09 (0.08) mg x l(-1)] and neurological and adaptive capacity scores was demonstrated.

A comparison of patient-controlled analgesia fentanyl and alfentanil for labour analgesia

PURPOSE

To determine the analgesic efficacy of equipotent doses of PCA (patient-controlled analgesia) fentanyl and PCA alfentanil for labour pain.

METHODS

Twenty three, ASA I - II parturients between 32-42 wk gestational age in whom epidural analgesia was contraindicated were randomized to receive PCA fentanyl (Group F)or alfentanil (Group A). Plain numbered vials contained 21 ml fentanyl 50 microg x ml(-1) or alfentanil 500 microg x ml(-1). A one millilitre loading dose was administered. The PCA solution was prepared by diluting 10 ml study drug with 40 ml saline and the PCA pump was programmed to deliver a dose of 2 ml, delay of five minutes and a basal rate of 2 ml x hr(-1). Maternal measurements obtained were hourly drug dose, total dose, Visual Analog Pain Score (VAPS) q 30 min, sedation score q 1 hr and side effects. Neonates were assessed by 1,5, and 10-min Apgar scores, umbilical venous and arterial blood gases and neurobehavioural scores at four and 24 hr.

RESULTS

Mean VAPS from 7 - 10 cm cervical dilatation were higher in Group A than in Group F (85.7+/-13.9 vs. 64.6+/-12.1; P<0.01) There were no inter-group differences in VAPS from 1-3 cm, or from 4-6 cm dilatation, in maternal sedation scores or side effects, or in neonatal outcomes.

CONCLUSION

In the doses prescribed in this study, PCA fentanyl was found to provide more effective analgesia in late first stage labour than PCA alfentanil.

Psychotropic drugs in mothers' milk: a comprehensive review of assay methods, pharmacokinetics and of safety of breast-feeding

Many mentally ill women want to breast-feed their babies but, if they are taking psychotropic drugs, there is very little systematic data upon which to base decisions about whether or not it is safe to do so. We therefore attempt to provide a comprehensive and critical summary of existing case reports and of studies of breast-feeding in relation to commonly used psychotropic drugs. The literature review focuses on the following drugs: antidepressants: tricyclics and serotonin selective reuptake inhibitors (SSRIs); antipsychotic drugs: chlorpromazine, perphenazine, haloperidol and clozapine; mood stabilizers: lithium and carbamazepine; and benzodiazepines. The research literature consists mainly of single case reports and there have been very few attempts at controlled, longitudinal investigations. Findings are often difficult to compare because of differences in methods or because of lack of key information. Most data are available about the tricyclic antidepressants but even here we have found that the reports cover only a grand total of 66 mother-infant pairs. Dilemmas about whether or not to contraindicate breast-feeding arise most commonly in relation to postnatal depression. The findings to date suggest that provided that infants are healthy at the outset it is likely that the benefits of breast-feeding will outweigh potential hazards if their mothers are taking established tricyclic drugs at recommended dose levels. Much less is known about risks associated with SSRI antidepressants or about antipsychotic drugs such as phenothiazines and butyrophenones or mood stabilizers such as carbamazepine, all of which enter breast-milk. Safeguards are suggested for future single case studies, which, as they accumulate, will provide a platform for mounting controlled prospective studies properly to test for any acute toxic effects and for possible long-term adverse effects of such drugs on infants' development. Appendix 1 is a review of assay methods. Appendix 2 examines pharmacokinetic factors in newborn preterm and sick infants with special reference to contraindications to breast-feeding. Appendix 3 is a review of methods for assessing infant health and development.

Comparison of epidural anaesthesia with ropivacaine 0.5% and bupivacaine 0.5% for caesarean section

PURPOSE

To compare ropivacaine 0.5% with bupivacaine 0.5% for epidural anaesthesia for Caesarean section.

METHODS

Healthy pregnant women, scheduled for elective Caesarean section were enrolled into this randomized, double-blind, parallel-group study. Epidural block was obtained with 20-30 ml of ropivacaine (group R) or bupivacaine (group B) and surgery started when anaesthesia was reached T6. Maternal heart rate and blood pressure and fetal heart rate were assessed before the test dose and at five minute intervals until the end of surgery. At the same intervals, sensory and motor block characteristics were determined. Apgar scores and Neurologic and Adaptive Capacity Scores (NACS) were determined after delivery. Adverse events were recorded.

RESULTS

Sixty-five patients were enrolled and data from 61 were available for analysis; 30 ropivacaine and 31 bupivacaine. Time from the end of the last injection to the start of surgery was 46 +/- 13 min (mean +/- SD) in gp R and 53 +/- 25 min in gp B (P:NS). The median duration of analgesia varied between 1.7 and 4.2 hr in gp R and between 1.8 and 4.4 hr in gp B (P:NS). In patients who developed Bromage 4 block, it persisted longer in those in gp B (2.5 hr) than in gp R (0.9 hr) (P < 0.05). The quality of analgesia was satisfactory in 27/29 patients (93%) in gp R and 27/31 patients (87%) in gp B (P:NS), although supplemental i.v. opioid was required in ten and seven patients, respectively. The most common adverse events in the mother were hypotension (63% gp R and 61% in gp B) (NS) and nausea (30% and 58%, in group R and B, respectively) (P = 0.05). Apgar scores were 7 after five minutes in all neonates.

CONCLUSION

Ropivacaine 0.5% and bupivacaine 0.5% provided effective epidural anaesthesia for Caesarean section although supplementation with i.v. opioid was commonly required.

An optimality score for the neurologic examination of the term newborn

We describe the application of a revised version of the Dubowitz neurologic examination of the newborn in 224 low-risk, term newborn infants. The method has been updated by eliminating less useful items and including new items evaluating general movements and patterns of distribution of tone. An optimality score is included to make the evaluation more quantitative and for comparison with sequential examinations with neurophysiologic and imaging findings. The score is based on the distribution of the scores for each item in the population of low-risk term infants. We defined not only the most common pattern for each item but also the variability of the findings by using 10th and 5th centiles. Because most of the items assessing tone and the Moro reflex varied with gestational age between 37 and 42 weeks, the changes were incorporated in the scoring system. The total optimality score was the sum of the optimality scores of individual items. Although the association of 4 or more deviant scores was found in less than 10% of our infants, deviant results on 1 or 2 single items could be observed in a third of this normal population, suggesting that isolated deviant signs have little diagnostic value. In contrast, an abnormal distribution of tone patterns, which we have commonly observed in infants with brain lesions, was not found in this cohort.

Pharmacokinetics and clinical effect during continuous epidural infusion with ropivacaine 2.5 mg/ml or bupivacaine 2.5 mg/ml for labour pain relief

BACKGROUND

Ropivacaine has shown less systemic toxicity than bupivacaine, and comparatively low muscle-blocking properties could constitute another advantage when used epidurally for obstetric pain relief. We aimed primarily to compare maternal and foetal drug disposition following continuous epidural infusion of ropivacaine or bupivacaine.

METHODS

Twenty-four full-term, nulliparous women were randomized to continuous epidural infusion (10 ml/h) of ropivacaine 2.5 mg/ml or bupivacaine 2.5 mg/ml for labour pain relief in a double-blind, parallel-group design. Maternal blood samples were collected up to 24 h after the end of infusion as well as taken from the umbilical cord at the time of delivery. Sensory and motor block as well as analgesia were assessed. All the women were monitored by cardiotocography and neonatal assessment was performed.

RESULTS

The sensory block was adequate for both drugs. Higher plasma levels (total and free) were seen with ropivacaine, although the infusion with bupivacaine continued on average for about 2 hours longer. However, the ratios between maternal and umbilical blood concentrations were similar for both drugs. Normal neonatal Apgar and neonatal adaptive capacity scores (NACS) were found in both groups.

CONCLUSION

A continuous epidural infusion of 25 mg/h ropivacaine or bupivacaine both produced good labour pain relief. Higher total and free plasma concentrations were seen for ropivacaine. The ratios between maternal and umbilical plasma levels were similar for both drugs.

Clinical pharmacokinetics of neuromuscular relaxants in pregnancy

Despite an increased in bodyweight, plasma volume by 45% and blood volume by 35% that might influence the volume of distribution of polar drugs, the apparent volume of distribution at steady state (Vss), volume of distribution (Vd) and the apparent volume of the central compartment (Vc) of atracurium, vecuronium and pancuronium are unchanged during pregnancy. With an elimination that is independent of renal, hepatic and enzymatic functions, the clearance of atracurium is also unchanged. This is corroborated by an unchanged clinical duration of atracurium during pregnancy. The clearance of pancuronium is increased by 27% during caesarean section. This may be explained by the increased glomerular filtration rate reported in pregnant women. The clinical duration of vecuronium in term and postpartum women is twice that reported in nonpregnant women. On the other hand, an increase in the clearance clearance of vecuronium during cesarean sections has been reported. The umbilical/maternal vein concentration ratio (UV/MV) of nondepolarising neuromuscular relaxants varies from 7 to 26% and clinical doses of these drugs may induce partial residual curarisation in neonates. Fetal concentrations of non-depolarising neuromuscular relaxants are proportional to the maternal dose injected as demonstrated for pancuronium and vecuronium. Increasing UV/MV with longer drug injection to delivery intervals have been demonstrated for drugs with a high molecular weight, such as atracurium, but not for those with a low molecular weight, such as vecuronium, while conflicting results have been reported for pancuronium. Despite decreased plasma pseudocholinesterases, the clinical duration of succinylcholine 1 mg/kg is unchanged in pregnant women, and only is slightly increased in postpartum women. On the other hand, larger doses of succinylcholine have induced prolonged apnoea and phase II block. The use of a pretreatment dose of a nondepolarising neuromuscular relaxant to decrease fasciculations and subsequent postoperative muscle pain is not only unnecessary in pregnant women but may be hazardous, since it may produce unexpected significant curarisation with respiratory distress. At clinical doses, transplacental passage of succinylcholine is insufficient to produce curarisation of neonates except in those born to mothers with abnormal plasma pseudocholinesterases. Magnesium sulfate, used in the treatment of pre-eclampsia, will enhance the blocking effects of nondepolarising neuromuscular relaxants but will have no effects on the characteristics of paralysis of succinylcholine. Histamine type 2 antagonists used to decrease the risk of aspiration during induction of anaesthesia do not influence the blocking properties of neuromuscular relaxants, while metoclopramide prolongs the block of succinylcholine.

Volume preload: lack of effect in the prevention of spinal-induced hypotension at caesarean section

A randomized double-blind study of 40 women was performed to compare blood pressure changes between two groups of women following induction of spinal anaesthesia for elective caesarean section. One group received a 1 L Ringer's solution preload, administered over 10 min, before spinal anaesthesia while the other group received no preload. In both groups a prophylactic infusion of ephedrine (60 mg in Ringer's solution 1000 ml) was started immediately following intrathecal injection of local anaesthetic. There was no significant difference either in the ephedrine requirements or the incidence of hypotension between the two groups. There were no differences between the groups in terms of neonatal outcome as assessed by Apgar score, umbilical arterial and venous blood pH, and Neonatal Adaptive Capacity Scores. When ephedrine is infused prophylactically immediately following spinal anaesthesia for elective caesarean section, a 1000 ml crystalloid preload confers no advantages in terms of maternal blood pressure control or neonatal outcome.

0.125% ropivacaine is similar to 0.125% bupivacaine for labor analgesia using patient-controlled epidural infusion

We compared the effects of 0.125% ropivacaine with 0.125% bupivacaine in laboring patients using patient-controlled epidural analgesia (PCEA). Fifty-one ASA physical status I or II term parturients with functioning epidural catheters were randomized to receive ropivacaine or bupivacaine using a prospective, double-blind design. Basal infusions (6 mL/h) were supplemented with patient-controlled boluses (5 mL) every 10 min as required. For inadequate analgesia, patients were administered 10-mL boluses of study solution until comfortable. There were no differences in verbal pain scores, amount of local anesthetics used, sensory levels, motor blockade, labor duration, mode of delivery, side effects, or patient satisfaction between the two local anesthetics. We conclude that 0.125% ropivacaine and bupivacaine are clinically indistinguishable and are both highly effective for labor analgesia using PCEA.

IMPLICATIONS

This study compared labor analgesia from 0.125% ropivacaine and 0.125% bupivacaine using patient-controlled epidural analgesia. We found no significant differences in local anesthetic use, analgesic characteristics, or side effects between 0.125% ropivacaine and 0.125% bupivacaine. We conclude that these two drugs are clinically indistinguishable at this concentration.

Epidural lidocaine for cesarean delivery of the distressed fetus

Lidocaine with epinephrine and sodium bicarbonate has a rapid onset of action. We therefore wished to compare its use with that of chloroprocaine for urgent cesarean delivery. Thirty parturients for cesarean section under epidural anesthesia were divided into three groups. Group 1 required elective cesarean section and served as the control group for neonatal lidocaine levels. Groups 2 and 3 had been receiving epidural infusions of 0.125% bupivacaine with epinephrine 1:400,000 and required urgent cesarean section. They were randomized to receive either 1.5% lidocaine with epinephrine or 3% chloroprocaine, both with sodium bicarbonate 2 ml in a total volume of 25 ml. All patients had adequate anesthesia and none required supplementation. The time from completion of injection to the achievement of a T4 sensory level was significantly shorter in the chloroprocaine group (3.1 vs. 4.4 min). There were no differences in Apgar scores or Neurologic and Adaptive Capacity Scores between the lidocaine and chloroprocaine groups. Lidocaine was detectable in maternal serum from four of the urgent cases and all of the elective cases. It was detectable in five neonates from the elective group but none from the emergency group. In parturients with preexisting epidural catheters and a baseline epidural infusion to maintain a T10 sensory level, chloroprocaine is faster in onset than lidocaine, but the difference in this study was only 1.3 min, and both agents provided excellent anesthesia.

Intravenous fentanyl PCA during labour

PURPOSE

To evaluate the usefulness of intravenous patient-controlled analgesia (PCA) fentanyl for labour analgesia, its effectiveness for maternal pain and safety for the fetus and newborn.

METHODS

Twenty primigravidas were randomised to receive intravenous PCA fentanyl or epidural analgesia for labour pain. Maternal pain, heart rate and arterial oxyhaemoglobin saturation (SpO2) were monitored. Fetal and neonatal monitoring included cardiotocogram (CTG), APGAR, neurological scoring and static-charge-sensitive bed (SCSB) recording for 12 hr postnatally with ECG and SpO2. Fentanyl concentrations and pH of umbilical artery and vein were analysed.

RESULTS

Initially, epidural analgesia was more effective (P = 0.01), and three patients in the fentanyl group were given epidural due to unsatisfactory pain relief. Overall satisfaction for analgesia did not differ between the groups. Maternal side-effects were more frequent in the fentanyl group (dizziness and tiredness most often, P = 0.0001). Severe side-effects were not reported. In CTG there were no differences between groups. All the newborns were healthy, APGAR and pH were normal. Naloxone was not used. Neurological scoring was similar in both groups. In 12 hr monitoring heart rate, breathing frequency and movement time were similar in both groups, but SpO2 was lower in the fentanyl group (P < 0.001). Umbilical cord fentanyl concentrations were low or beyond the detection limit.

CONCLUSION

Intravenous fentanyl can be used for labour analgesia with the doses reported here as an alternative to epidural analgesia. However, the fetus and neonate must be appropriately monitored. Naloxone and oxygen should be available if neonatal distress occurs.

Intrathecal sufentanil, fentanyl, or placebo added to bupivacaine for cesarean section

We compared the effects of intrathecal sufentanil 2.5 and 5 microg, fentanyl 10 microg, and placebo when administered together with hyperbaric bupivacaine 0.5% 12.5 mg for cesarean section. The study was performed in a randomized, double-blind fashion in 80 (20 per group) healthy, full-term parturients presenting for elective cesarean section. Postoperative pain was assessed using the visual analog scale (VAS). Duration of complete analgesia was defined as the time from the intrathecal injection to VAS score > 0. Duration of effective analgesia was defined as the time to VAS score > or = 4. No patient experienced intraoperative pain. Complete analgesia was prolonged in all groups receiving opioids. Effective analgesia was prolonged and the 0- to 6-h intravenous opioid requirements were lower in the groups receiving sufentanil compared with those receiving fentanyl and placebo. The need for intraoperative antiemetic medication was greater in the placebo group. Pruritus was a frequent and dose-related side effect in the groups receiving sufentanil. There were no differences in umbilical cord blood gases or neonatal Apgar scores and neurological and adaptive capacity scores among the groups. In conclusion, the addition of sufentanil or fentanyl improved the quality of subarachnoid block compared with placebo. The duration of action was longer for sufentanil than fentanyl.

IMPLICATIONS

Small doses of fentanyl or sufentanil (synthetic opioids) added to bupivacaine (local anesthetic) for spinal anesthesia for cesarean section reduce the need for intraoperative antiemetic medication and increase the duration of analgesia in the early postoperative period compared with placebo.

Comparison of 0.25% ropivacaine and bupivacaine for epidural analgesia for labor and vaginal delivery

STUDY OBJECTIVE

Part 1: To measure ropivacaine levels in the mother and infant at delivery after continuous lumbar epidural infusion. Part 2: To compare epidural ropivacaine to epidural bupivacaine for labor analgesia in regard to effectiveness, motor blockade, and maternal and neonatal effects.

DESIGN

Part 1: Open-labelled, non-blind study. Part 2: Randomized, double-blind study.

SETTING

Labor and delivery units of two academic hospitals.

PATIENTS

Part 1: 20 ASA physical status I and II parturients in active labor. Part 2: 81 ASA physical status I and II parturients in active labor.

INTERVENTIONS

For Part 1, 8 to 12 ml of 0.25% ropivacaine was administered through a lumbar epidural catheter to achieve a T10 dermatomal sensory level. An infusion of 0.25% ropivacaine, 8 to 10 ml/hr, maintained this sensory level. Maternal and umbilical cord blood samples obtained at delivery were analyzed for ropivacaine concentration. For Part 2, anesthetic management was similar to that previously described except patients were randomized to receive either 0.25% ropivacaine or 0.25% bupivacaine. Onset, regression, maximal spread of sensory block, and onset and degree of motor blockade were measured. Contraction pain as assessed using a visual analog scale (VAS), maternal blood pressure, and heart rate were determined every 5 minutes until a stable VAS-contraction score was achieved, and every 30 minutes thereafter. Neonatal assessment included Apgar scores and neurologic and adaptive capacity scores (NACS) at 15 minutes, 2 hours, and 24 hours.

MEASUREMENTS AND MAIN RESULTS

For Part 1, the total and free maternal arterial concentrations of ropivacaine at delivery were 0.64 +/- 0.14 microgram/ml and 0.10 +/- .02 microgram/ml, respectively; the umbilical venous total and free concentrations were 0.19 +/- 0.03 microgram/ml and 0.12 +/- 0.07 microgram/ml, respectively (n = 12). The umbilical arterial and venous concentrations did not differ for both the free and total concentrations. For Part 2, there was no difference between ropivacaine and bupivacaine in the variables measured. Umbilical cord gases and Apgar scores were not different between the two groups; NACS were higher at 15 minutes and 2 hours in the ropivacaine group (p < 0.05) than the bupivacaine group.

CONCLUSION

Both ropivacaine and bupivacaine produced excellent analgesia for labor with no major adverse effect on the mother or neonate.

Ropivacaine 7.5 mg/ml for elective caesarean section. A clinical and pharmacokinetic comparison of 150 mg and 187.5 mg

BACKGROUND

The new, long-acting local anaesthetic ropivacaine has shown less systemic toxicity than bupivacaine and a concentration of 7.5 mg/ml can therefore be used for epidural anaesthesia in Caesarean section. The present pilot study was undertaken to find indications for an optimal dosage by comparing the clinical effects, quality of anaesthesia and pharmacokinetics of ropivacaine 150 mg (lower dose = LD) vs 187.5 mg (higher dose = HD) for women undergoing elective Caesarean section under epidural anaesthesia.

METHODS

Sixteen full-term women scheduled for elective Caesarean section in two equal-sized consecutive groups received 20 or 25 ml ropivacaine epidurally in this non-randomised, open study. Study parameters included sensory and motor blockade, circulatory response, intraoperative pain and discomfort, neonatal evaluation and pharmacokinetic determinations.

RESULTS

Block height varied between T5 and T2 in the LD group, whereas the HD group produced 4 unnecessarily high blocks (C8 in 3 women and C7 in 1 woman). Surgical anaesthesia was excellent in both groups. Circulatory stability was pronounced in the LD group (no ephedrine given), while 4 women required ephedrine in the HD group. Neonatal outcome as judged by Apgar scores; umbilical blood gas determinations and NACS scores were excellent in both groups. The plasma concentration-time profiles indicated linearity in the concentration range studied, with similar clearance values to those reported previously. Placental drug equilibrium was rapid; however, the foetal drug exposure depended on intrauterine exposure time.

CONCLUSIONS

20-25 ml ropivacaine 7.5 mg/ml produced very satisfactory conditions for elective Caesarean section under epidural anaesthesia. In this small population, 150 mg ropivacaine seemed optimal, while 187.5 mg produced unnecessarily extended block height in 50% of the women.

Double-blind comparison of epidural ropivacaine 0.25% and bupivacaine 0.25%, for the relief of childbirth pain

PURPOSE

To evaluate the efficacy of ropivacaine 0.25% when administered epidurally for relief of labour pain and to compare it with bupivacaine 0.25%.

METHODS

In a multicentre investigation, 60 ASA I and II labouring women were randomized in a double-blind fashion to receive either bupivacaine 0.25% or ropivacaine 0.25% administered epidurally by intermittent top-up for labour analgesia. Using a standardized technique, epidural analgesia was initiated after the woman received 10-15 ml-kg.1 crystalloid solution. Maternal blood pressure, heart rate, analgesia sensory level, degree of motor block and visual analogue pain scores were measured by the research nurse prior to, and at regular intervals, following the administration of analgesia. Total dose of local anaesthetic administered, duration of labour, mode of delivery, and maternal and fetal/neonatal side effects were noted. The fetus/neonate was assessed by the research nurse using the fetal heart rate tracing, Apgar scores at delivery and neonatal neurobehavioural assessments at 2 and 24 hr postnatally. Maternal and investigators' satisfaction with the analgesia achieved was assessed after delivery.

RESULTS

No differences were found between the two agents in any of the variables studied.

CONCLUSION

Ropivacaine 0.25%, when administered epidurally by intermittent top-ups for labour analgesia, was equally efficacious as bupivacaine 0.25%.

Do labor medications affect breastfeeding?

Do labor medications affect breastfeeding? Few studies examine breastfeeding as an outcome of labor medication. While parents may be told that labor medications and epidurals have no effect on newborns, the literature reports significant neurobehavioral effects of these medications on the newborn and the mother-infant relationship.

Investigation of pharmacokinetics and of possible adverse effects in infants exposed to tricyclic antidepressants in breast-milk

We have studied ten breast-feeding mothers who were prescribed tricyclic antidepressant drugs and have also compared their infants' development with a similar group (n = 15) who were bottle-fed. Concentrations of tricyclic drugs in maternal plasma and urine, in fore-milk and hind-milk and in infant plasma (n = 6) and urine (n = 9) were measured by gas chromatography (GC) and by an enzyme immunoassay (EIA). The fat concentration in milk was also measured. Infants health and development were monitored by physical examination and by the Bayley Scales of Infant Development up to 30 months. The amounts of tricyclic drugs and their principal metabolites in maternal plasma were significantly correlated with the oral dose and with the amounts in breast-milk. Drug concentrations in fore-milk, but not in hind-milk, increased in line with its fat content, which was maximal in hind-milk. Correlations between gas chromatographic and enzyme immunoassays of maternal samples were high provided that the values for amitriptyline and nortriptyline were excluded; immunoreactivities to these compounds were abnormally high, suggesting that metabolites were also being measured by EIA. The daily doses of drugs ingested by breast-fed infants were about 1% of the maternal dose/kg and the immunoassay detected very small amounts of tricyclics in infants' plasma and urine. No acute toxic effects were found in the ten medicated breast-fed infants and there was no evidence of developmental delays in comparison with bottle-fed infants. Although the number of subjects in this study is small, when taken in conjunction with other published findings, we have not found any reason to prevent mothers who are taking established tricyclic antidepressants from breast-feeding their babies if they want to do so.

Anesthetic quality during cesarean section following subarachnoid or epidural administration of bupivacaine with or without fentanyl

BACKGROUND

It is often assumed that subarachnoid administration of local anesthetics produces a more profound blockade than epidural anesthesia. Furthermore, the addition of fentanyl has been reported to increase preferentially intraoperative analgesia. In the present study we set out to study these two issues in a randomized and controlled study with respect to perceived pain and discomfort during surgery and postoperative pain.

METHODS

In the present study, 100 parturients subjected to elective cesarean section, 34 nullipara and 66 multipara, received one out of four combinations of the local anesthetic bupivacaine and the opioid fentanyl; group A--bupivacaine 12.5 mg + 10 micrograms fentanyl subarachnoidally, group B--bupivacaine 12.5 mg + saline subarachnoidally, group C--bupivacaine 100 mg + 100 micrograms fentanyl epidurally, group D--bupivacaine 100 mg + saline epidurally; N = 25 in each group. Pain intensity and discomfort during surgery was assessed with a visual analogue scale (VAS). Postoperative pain intensity and need for analgesics postoperatively, ketobemidone, was registered for 24 h following surgery.

RESULTS

Intraoperative pain intensity and discomfort did not differ significantly between parturients in any of the four groups Postoperative pain was significantly more intense in parturients receiving local anesthetics subarachnoidally as compared to the epidural groups during the first 6-h period. This difference was also reflected in a significantly increased consumption of analgesics during this period. No significant differences between the groups were observed with regard to hemodynamics (blood pressure), respiration (oxygen saturation) or other effects such as nausea or itching. All neonates had normal Apgar and neonatal adaptive capacity scores (NACS).

CONCLUSION

We conclude that subarachnoidal (12.5 mg) and epidural (100 mg) injections with bupivacaine both produced adequate anesthetic quality in women undergoing elective cesarean section. The addition of fentanyl (10 micrograms subarachnoidally or 100 micrograms epidurally) did not significantly improve the quality of these already profound blockades.

Respiratory effects of spinal anaesthesia for caesarean section

We report the changes observed in a number of pulmonary function tests performed on 36 patients undergoing Caesarean section under spinal anaesthesia. The tests comprised peak expiratory flow, forced expiratory volume in one second, forced vital capacity, forced expiratory volume in one second to forced vital capacity ratio and the maximal mid-expiratory flow. Significant changes occurred that are consistent with a restrictive ventilatory defect. These changes persisted for four hours after the induction of spinal anaesthesia. Administration of 35% oxygen by facemask failed to change significantly fetal umbilical vein pH or partial pressure of oxygen.

Labor analgesia and infant brain development

A large percentage of newborns are exposed to pharmacological agents that affect the brain in connection with pain management during labor. The two most commonly used agents are meperidine, administered intravenously or intramuscularly, and bupivacaine, administered by the epidural route. Over the years, infant behavioral assessments have been used in the neonatal nursery to identify labor analgesia regimens with minimal impact on neonatal status. However, considerable controversy has centered on the general issue of possible harm to the neonate from use of analgesia and anesthesia in obstetrics. Due to limitations on experiments in the obstetric situation and a lack of suitable animal models, the broader issues concerning the effects of these agents on the developing brain and possible long-term consequences for infant adaptive functioning have received little attention. A series of studies has recently been completed using a rhesus monkey model for administration of labor analgesia under controlled experimental conditions and long-term behavioral evaluation of infants. Most of the assessments, including those of cognitive function, were not influenced by perinatal analgesia. However, these studies have confirmed the neonatal depressant effects of meperidine and have suggested that the course of behavioral maturation during certain periods of infancy is influenced by both meperidine and bupivacaine administration at birth. These effects could occur as a result of effects on vulnerable brain processes during a sensitive period, interference with programming of brain development by endogenous agents, or alteration in early experiences.

The effect of epidural opioids on maternal oxygenation during labour and delivery

The effects of epidural fentanyl on the incidence of maternal hypoxaemia during labour and on neonatal welfare were examined. Women were randomly allocated to receive one of two epidural infusions, bupivacaine 0.125% alone or bupivacaine 0.0625% with 2.5 micrograms.ml-1 fentanyl, and maternal arterial oxygen saturation was monitored continuously until delivery. The median incidence of desaturation (SpO2 < 95%) during the active phase of the second stage of labour was significantly greater in the fentanyl group than in controls (2.9 versus 0.6 min.h-1, p = 0.02). Similarly, the incidence of desaturation to SpO2 < or = 90% was greater in the fentanyl group than in controls (p = 0.02). There was no correlation between maternal oxygenation or plasma fentanyl concentration and neonatal welfare as measured by umbilical arterial and venous blood gas and acid base status, Apgar score and Neurologic and Adaptive Capacity Score.

Shock of birth. Evaluation of neurologic status of term newborn in the first 48 hours of life

The shock of birth is a transient depression of muscle tone and deep tendon reflexes seen in newborn babies shortly after birth. We evaluated the shock of birth in a sample of 313 consecutive term newborns at 4, 24 and 48 hours of life. We correlated neurologic findings on examination with maternal, obstetric and perinatal data. Special attention was given to the relationship between the mode of delivery and shock of birth. Of the maternal data, factors associated with the shock of birth were obstetric gestational age, previous gestations, abortion or previous vaginal deliveries. Presence of stained amniotic fluid at birth was associated with the shock of birth. There was also a correlation between shock of birth and newborn sex, birth weight, thoracic circumference and the Battaglia and Lubchenco classification. The shock of birth lasted less than 24 hours in 70% of the newborns and less than 48 hours in 84.3%. We conclude that the mode of delivery, vaginal or cesarean section, did not influence the shock of birth. We also established the duration and factors associated with this phenomenon.

Epidural infusion of low-dose bupivacaine and opioid in labour. Does reducing motor block increase the spontaneous delivery rate?

Labouring women were randomly allocated to receive epidural infusions during labour of either 0.125% plain bupivacaine (n = 200) or a combination of 0.0625% bupivacaine with either 2.5 micrograms.ml-1 fentanyl or 0.25 micrograms.ml-1 sufentanil (n = 199) each starting at 12 ml.h-1 and adjusted as necessary to maintain analgesia. The dose of bupivacaine, both hourly (p < 0.001) and total (p < 0.001), was significantly lower in the group receiving the combination. Motor block was significantly less common and less severe in the combination group (p < 0.001). These reductions did not result in a significant increase in spontaneous deliveries. Maternal satisfaction with first (p < 0.001) and second stage analgesia (p < 0.001) was significantly increased in the combination group. The addition of opioid to the epidural infusion did not reduce the incidence of perineal pain. There were no significant differences between the groups in neonatal outcome or the incidence of early postnatal symptoms.

Desflurane: a new volatile anesthetic for cesarean section. Maternal and neonatal effects

Desflurane, a new volatile anesthetic agent with low blood/gas solubility, has recently been studied in clinical and animal trials but its use in obstetrics has not been adequately evaluated. This prospective study was undertaken to evaluate the maternal and neonatal effects of desflurane in obstetrical patients. Seventy-five healthy parturients undergoing primary or repeat cesarean section were randomly assigned to one of three groups of 25 each, end-tidal 3% desflurane, 6% desflurane or 0.6% enflurane, combined with 50% N2O and O2. All patients had rapid sequence induction of anesthesia with thiopentone sodium followed by succinylcholine for tracheal intubation. After delivery, anesthesia was maintained with reduced concentration of desflurane or enflurane with 67% N2O in O2, supplemented by butorphanol tartrate. Maternal hemodynamic parameters, blood loss and maternal awareness during surgery were monitored. Neonatal outcome was evaluated by Apgar scores, neurological and adaptive capacity scores (NACS), cord blood gas and acid-base status, and time to sustained respiration (TSR). Maternal blood loss did not differ significantly between the three groups and none of the patients developed intraoperative awareness. All three groups responded to psychomotor performance equally fast. Patients in all three groups developed transient hypertension and tachycardia during induction of anesthesia which returned to baseline values in approximately 5 min. Neonatal outcome was equally good in the three groups. More neonates in the 6% desflurane group had TSR > 90 s compared to the 3% desflurane group (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)