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

Use of sevoflurane during elective cesarean birth: a comparison with isoflurane and spinal anesthesia

This randomized study compared sevoflurane 1% and isoflurane 0.5% in terms of maternal and neonatal outcomes. In addition, neonatal outcome in both groups was compared with a cohort of patients delivered by cesarean birth using spinal anesthesia. Fifty-five patients presenting for elective cesarean birth under general anesthesia were randomly assigned to receive either sevoflurane 1% or isoflurane 0.5% in a 50% nitrous oxide and oxygen mixture for maintenance. Twenty patients requesting regional anesthesia received a subarachnoid block using 1.5 mL bupivacaine 0.75% in 8.25% dextrose with fentanyl 10 micrograms. Intraoperative hemodynamic variables and perioperative adverse events were recorded. Neonatal data included Apgar scores at 1 and 5 min, umbilical artery gas analysis, neurologic adaptive capacity scores (NACS) at 2 and 24 h, and a modified neonatal behavioral assessment scale (NBAS) at 24 h. Sevoflurane and isoflurane at equianesthetic concentrations (0.46 MAC-h [minimum alveolar anesthetic concentration hours]) were associated with similar blood pressure and heart rate changes during the operation. Blood loss, uterine tone, and perioperative complications were not problematic and were similar with the two drugs. No differences were seen in emergence times or in the time to being judged fit for discharge from the recovery room. Similarly, the level of postoperative comfort was the same in both groups. Comparing the general and the spinal anesthetic groups, no differences could be detected in neonatal outcome. Fluoride concentrations were modestly increased above preoperative levels in maternal and umbilical blood samples after sevoflurane administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidural clonidine-fentanyl combination for labour analgesia: a comparison with bupivacaine-fentanyl

This open study of 20 women compared epidural clonidine (300 microg)/fentanyl (100 microg) with bupivacaine (25 mg)/fentanyl (100 microg) in the provision of pain relief in labour. Sensory tests in the clonidine group revealed slight alterations in the appreciation of pin prick and temperature but motor power was unchanged. Analgesia after the first dose was similar in the two groups, but thereafter the analgesia provided by clonidine/fentanyl was less than that from bupivacaine/fentanyl. Despite the incomplete pain relief provided by clonidine/fentanyl, mothers appreciated their essentially normal sensations and muscle power. Midwives also commented favourably on the normal mobility of these labouring mothers. There was no difference between the two groups in the duration of labour or the condition of the infants.

Influence of epidural analgesia on fetal and neonatal well-being

Epidural analgesia is a frequently used method to reduce the pain of child-bearing. Concerns regarding the safety and potential hazards still persist in the medical community. This review intends to examine how epidural analgesia determines the various factors of fetal and neonatal well-being. Placental drug transfer of opiates like morphine, pethidine and fentanyl is rapid and can lead to neonatal depression. Sufentanil seems to be the safest opiate to administer epidurally. Local anaesthetics are transferred to the fetus in substantial amounts, but the reported effects are subtle and are probably inconsequential. Utero- and fetoplacental blood flow seems to be improved by epidural analgesia with local anaesthetics. Even when using stronger solutions for more extensive blockade in patients for caesarean section, no adverse effects could be demonstrated using pulsed Doppler technique as long as prolonged hypotension (> 2 min) is avoided. Hypotension is best prevented with 20-25 ml/kg crystalloid preload and prompt treatment with ephedrine or etilephrine. Addition of adrenaline to local anaesthetics is considered to be safe for the healthy mother and fetus but it should best be avoided in mothers with pregnancy induced hypertension. Fetal and neonatal acid-base balance and gas-exchange are not adversely affected by epidural analgesia. Many studies show that epidural analgesia can indeed protect the fetus if hypotension is prevented. Neonatal well-being evaluated by APGAR, BRAZELTON, SCANLON and NACS scores is not significantly influenced by local anaesthetics. Neonatal depression can occur however with epidural use of morphine, fentanyl and alfentanil. Sufentanil, again in doses up to 30 micrograms in association with bupivacaine seems to be devoid of depressive effects on the neonate. In summary, the anaesthetist has good arguments to reassure his obstetrical colleagues that providing epidural analgesia for pregnant women in labour is a justifiable intervention to support the natural process of child-bearing.

Epidural infusion of alfentanil or diamorphine with bupivacaine in labour--a dose finding study

Following induction of epidural analgesia with 0.375% bupivacaine, 120 healthy parturients were randomly assigned in a double blind fashion to one of eight infusion groups. All received 8 ml.h-1 of 0.125% bupivacaine either alone (control group), or with alfentanil at 133, 266 or 400 micrograms.h-1 (groups A1-A3) or with diamorphine at 133, 266, 400 or 533 micrograms.h-1 (groups D1-D4). Significantly longer top-up intervals were achieved with the two highest doses of both alfentanil and diamorphine when compared with bupivacaine alone (p < 0.01), making the minimum effective doses 266 micrograms.h-1 of alfentanil and 400 micrograms.h-1 of diamorphine. Perineal analgesia was better in all the opioid groups compared with the control group (p < 0.05). The intensity of motor block was greater in the control group (p < 0.05). The incidence of pruritus did not differ between groups. The highest dose of diamorphine caused significantly more nausea. No significant neonatal side-effects were demonstrated.

Anaesthesia for caesarean section (epidural and general): effects on the neonate

Anaesthesia may impair the condition of the neonate either directly (largely mechanically in utero or due to the influence of drugs) or indirectly via alteration of placental perfusion. These influences may further differ during normal caesarean section from those under complicated conditions. The criteria with which neonatal conditions are estimated need to be carefully distinguished with respect to results obtained. Neurobehavioural test results may give different information to the observer. A variety of drugs, not simply one, is used during general anaesthesia (GA). Even the consequences of maternal stress-fetal and neonatal levels of catecholamines or endogenous peptides may play a role. Local anaesthetics are known to cross the placenta as general anaesthetics do; in most cases, their effects are clinically irrelevant. Fetal and neonatal deliterious effects of regional anaesthesia (RA) are mainly related to maternal hypotension and the administration of large doses of local anaesthetics. If adequate doses of local anaesthetics and/or opioids are used, alterations in neurobehavioural scores are subtle and transient. Under normal maternal and fetal conditions, GA and RA are almost identically useful with respect to neonatal well being after caesarean section; subtle and inconsistent neurobehavioral residua may be present for a short period of time following GA. Under conditions of a compromised fetus, the neonate may however benefit from epidural anaesthesia more than from GA.

Desflurane analgesia for vaginal delivery

The use of subanaesthetic concentration of inhalational anaesthetic for vaginal delivery offers many advantages to the mother and newborn. Desflurane, with the characteristics of rapid onset and minimal metabolism, may provide better analgesia and safety for labour pain control. Eighty healthy parturients were randomly assigned to receive either desflurane 1.0-4.5% and oxygen (n = 40) or nitrous oxide 30-60% in oxygen (n = 40). Analgesia was assessed using a score from 0 (no relief) to 4+ (excellent analgesia), amnesia for the delivery, blood loss were recorded. Neonates were evaluated by Apgar scores and neurologic and adaptive capacity scores (NACS). Data were analyzed for statistical significance using Student's t-test or Chi-square when appropriate. Analgesia scores were similar for both groups with more amnesia in desflurane group (23% vs 0% P < 0.05). Blood loss did not differ significantly, 364 ml for the desflurane group and 335 ml for the nitrous oxide group. There were no significant differences for neonatal Apgar score at 1 min or at 5 min or the NACS at 2 hr or 24 hr between the two groups. We conclude that desflurane in subanaesthetic doses is safe and effective inhalation agent for normal delivery but might be associated with amnesia.

Intravenous propofol vs thiamylal-isoflurane for caesarean section, comparative maternal and neonatal effects

Several studies on propofol (Diprivan) for induction of anaesthesia during caesarean section have demonstrated its safety, however, it safety during maintenance of anaesthesia is not yet fully evaluated. The present study was undertaken to compare the maternal and neonatal effects of propofol or isoflurane in 74 term parturients undergoing primary or repeat caesarean section. Patients were randomly assigned to two groups, propofol group (n = 37) received propofol 1.5-2.5 mg.kg-1 for induction followed by a continuous infusion of propofol of 0.05-0.2 mg.kg-1.min-1. The isoflurane group (n = 37) received thiamylal 3-4mg.kg-1 for induction followed by isoflurane 0.25-0.75% for maintenance. All patients had rapid sequence induction using succinylcholine and endotracheal intubation, 50% N2O and O2 were used in all patients until delivery. After delivery N2O concentration was increased to 67% and intravenous butorphanol (Stadol) was given as needed. Patients in the propofol group had less hypertension after intubation (P < 0.05) and this was also of shorter duration compared to patients in the isoflurane group (5 min vs 10 min respectively). Maternal blood loss as well as intraoperative awareness and recovery time did not differ significantly between the two groups. Neonatal status as ascertained by Apgar scores, cord acid base status and the neurological and adaptive capacity scores (NACS) was equally good in both groups. It is concluded that propofol used for induction and maintenance of anaesthesia is a safe alternative to thiamylal/isoflurane for patients undergoing caesarean section and is associated with less hypertensive response during laryngoscopy and intubation.

Ropivacaine 0.25% versus bupivacaine 0.25% for continuous epidural analgesia in labor: a double-blind comparison

We compared the effects of continuous epidural infusion of ropivacaine 0.25% with bupivacaine 0.25% on pain relief and motor block during labor, and on the neonate. Seventy-six full-term parturients in active labor requiring epidural analgesia were randomly allocated to receive either bupivacaine 0.25% or ropivacaine 0.25%. Fifteen minutes after a loading dose of 10 mL of the study drug, an epidural infusion with the same drug was started at 6-12 mL/h to maintain an adequate block. Top-up doses of 6-10 mL were given as required. At full cervical dilation, the epidural infusion was discontinued. The onset of pain relief (verbal scale), contraction pain (visual analog scale), intensity of motor block (modified Bromage scale), and duration of motor block were not statistically different between the groups. Apgar scores at 1 and 5 min after delivery were comparable. There was a higher proportion of the neonates in the ropivacaine group (26/31 = 84%) who had a neurologic and adaptive capacity score (NACS) > or = 35 2 h after delivery than in the bupivacaine group (18/29 = 62%). We conclude that ropivacaine 0.25% and bupivacaine 0.25% are equally effective for epidural pain relief during labor. Ropivacaine may have an advantage over bupivacaine regarding neonatal neurobehavioral performance during the first few hours after delivery, although further studies will be required to substantiate this.

Double-blind comparison of intravenous butorphanol (Stadol) and fentanyl (Sublimaze) for analgesia during labor

OBJECTIVE

Our purpose was to compare the analgesic properties, effect on labor, and maternal-fetal side effects of intravenous butorphanol and fentanyl.

STUDY DESIGN

One hundred patients with uncomplicated term pregnancies were enrolled during early active labor. Each patient received standard doses of either fentanyl (50 to 100 micrograms) or butorphanol (1 to 2 mg) hourly on request in a double-blind manner. Pain was scored independently by the nurse and patient with a 10-point visual analog scale. Categoric and measurement data were collected for comparison of the effects on uterine activity, maternal and fetal well-being, and neonatal outcomes.

RESULTS

The fentanyl (n = 50) and butorphanol (n = 50) groups were identical with respect to maternal age, race, parity, and weight. Greater improvement in pain relief was found after the first dose of butorphanol than after fentanyl (p < 0.05). When fentanyl was given, either more doses were necessary (3.2 +/- 1.3 vs 2.1 +/- 1.1, p < 0.01) or epidural analgesia was requested more often (16%, 32% vs 9%, 18%, p < 0.05). Uterine contraction patterns for the first hour after dosing were unchanged, and the duration of the first and second stages of labor were not different between the two groups. No differences in maternal or newborn adverse effects were observed.

CONCLUSIONS

Both drugs were equally safe and without effect on active labor. Butorphanol provided better initial analgesia than fentanyl with fewer patient requests for more medication or epidural analgesia.

The effect of acute volume expansion and vasodilatation with verapamil on uterine and umbilical artery Doppler indices in severe preeclampsia

Preeclampsia is associated with increased peripheral, uterine, and umbilical artery resistance. Acute blood pressure reduction may result in shunting of blood and sudden fetal distress. We therefore investigated the effects of volume expansion and verapamil therapy on uteroplacental and umbilical resistance during treatment of preeclampsia.

MATERIALS AND METHODS

Five severe preeclamptics underwent volume expansion and subsequent vasodilatation with an infusion of verapamil. Invasive hemodynamic monitoring and Doppler ultrasonography were used to study changes in maternal, uterine, and umbilical hemodynamics.

RESULTS

Volume expansion and subsequent verapamil therapy was associated with significant changes in maternal hemodynamics without significant change in uteroplacental or umbilical resistance. Uterine artery waveform changes were noted, with disappearance of notching in some cases.

CONCLUSIONS

Volume expansion and verapamil therapy effectively reduces maternal blood pressure in preeclampsia, without adversely affecting uteroplacental or umbilical artery resistance. Uterine artery waveform changes may be associated with improved fetal outcome.

Comparison of two fentanyl doses to improve epidural anaesthesia with 0.5% bupivacaine for caesarean section

Ninety women undergoing elective caesarean section under epidural anaesthesia were double blindly randomised into three groups to receive either 2 ml of saline or 50 or 100 micrograms of fentanyl in 2 ml volume added to 0.5% bupivacaine. Both doses of fentanyl intensified the epidural anaesthesia and reduced patient discomfort during the operation. In both fentanyl groups the epidural blockade more often reached the 5th thoracic segment (P = 0.0258), the patients had significantly less pain (P = 0.0256), needed less intravenous diazepam medication during the operation (P = 0.0005) and the operating conditions were were better when compared to the saline group (P = 0.0416). There was no difference between the groups in the condition of the neonates as assessed by the Apgar score and cord blood pH. The postoperative time until treatment for pain was requested by the patients was more than 1 h longer in the fentanyl groups, but there was no difference in the total amount of postoperative analgesics needed during the first 24 h when compared to the saline group. Mild pruritus not requiring treatment was more common in fentanyl groups than in the saline group (P = 0.0187). The results suggest that 50 micrograms of fentanyl added to 0.5% bupivacaine increases patient comfort and improves the quality of epidural anaesthesia for caesarean section, and that adding 100 micrograms does not give further advantage.

The effect of intrapartum epidural analgesia on nulliparous labor: a randomized, controlled, prospective trial

OBJECTIVE

Our purpose was to determine the effect of epidural analgesia on nulliparous labor and delivery.

STUDY DESIGN

Normal term nulliparous women in early spontaneous labor were randomized to receive either narcotic or epidural analgesia.

RESULTS

When compared with the group receiving narcotic analgesia (n = 45), the group receiving epidural analgesia (n = 48) had a significant prolongation in the first and second stages of labor, an increased requirement for oxytocin augmentation, and a significant slowing in the rate of cervical dilatation. Epidural analgesia was associated with a significant increase in malposition (4.4% vs 18.8%, p < 0.05). Cesarean delivery occurred more frequently in the epidural group (2.2% vs 25%, p < 0.05), primarily related to an increase in cesarean section for dystocia (2.2% vs 16.7%, p < 0.05).

CONCLUSIONS

In a randomized, controlled, prospective trial epidural analgesia resulted in a significant prolongation in the first and second stages of labor and a significant increase in the frequency of cesarean delivery, primarily related to dystocia.

Epidural infusions for nulliparous women in labour. A randomised double-blind comparison of fentanyl/bupivacaine and sufentanil/bupivacaine

Sixty nulliparous women received epidural infusions in labour of 0.0625% bupivacaine containing either 2.5 micrograms.ml-1 of fentanyl or 0.25 micrograms.ml-1 of sufentanil, each starting at 12 ml.h-1. The duration of each stage of labour did not differ significantly between the groups nor did the mode of delivery. The quality of analgesia in the first and second stages of labour and at delivery was similar in the two groups and there were no significant differences in the bupivacaine dose requirements. In the fentanyl group, 90% of women required one or no top-ups compared with 87% in the sufentanil group. Five women in the fentanyl group and four in the sufentanil group developed motor blockade, limited to movement of the hip only. Six women (20%) in each group reported pruritus. There were no significant differences in Apgar scores, umbilical cord blood pH levels or neurologic and adaptive capacity scores at 2 or 24 h. Satisfaction with first and second stage analgesia was high with no differences between the groups. There were no significant differences in the incidence of postnatal symptoms with 52% of women reporting perineal pain and 45% localised backache.

Which induction drug for cesarean section? A comparison of thiopental sodium, propofol, and midazolam

STUDY OBJECTIVE

To determine maternal and neonatal effects of three different induction drugs (thiopental sodium, propofol, and midazolam) for cesarean section.

DESIGN

Randomized, double-blind study.

SETTING

Inpatient obstetric department at a general hospital.

PATIENTS

90 healthy patients undergoing elective cesarean section with general anesthesia.

INTERVENTIONS

3 groups of 30 patients each receiving thiopental 5 mg/kg, propofol 2.4 mg/kg, or midazolam 0.3 mg/kg for induction of anesthesia.

MEASUREMENTS AND MAIN RESULTS

Time to induce anesthesia, hemodynamic changes, depth of anesthesia, recovery after anesthesia, placental transfer, and neonatal outcome (Apgar and neurobehavioral examinations) were studied. In the thiopental and midazolam groups, systolic blood pressure and heart rate rose following endotracheal intubation and skin incision (p < 0.001 and p < 0.0025, respectively), while in the propofol group, there was significant hypotension after induction (p < 0.005). Electroencephalographic patterns showed a light depth of anesthesia with propofol and midazolam between anesthesia induction and delivery, confirmed by the presence of clinical signs of light anesthesia in 50% of propofol patients and 43% of midazolam patients. Time to induce anesthesia was longer with midazolam (p < 0.0001). Neonates in the midazolam and propofol groups had lower Apgar and neurobehavioral scores than those in the thiopental group. Umbilical artery to umbilical vein ratios were above 1 in the propofol and midazolam groups.

CONCLUSION

Thiopental still remains the first-choice induction drug for cesarean section. The slow induction time with midazolam may put the mother at risk for pulmonary inhalation. A plane of anesthesia that may risk awareness and potential neonatal depression is the main drawback of the two newer induction drugs.

Alkalinization improves the quality of lidocaine-fentanyl epidural anaesthesia for caesarean section

This double-blind randomized study of 116 healthy women was undertaken to evaluate whether alkalinization potentiated the analgesic effects of epidural fentanyl-lidocaine for elective Caesarean section. After a test-dose of 3 ml, lidocaine 2% with adrenaline 1:200,000, all patients received 100 micrograms, fentanyl in 5 ml saline and they were then divided into two groups, to receive incremental doses of 5 ml lidocaine 2% with adrenaline 1:200,000 with or without 0.1 mEq.ml-1 sodium bicarbonate, to obtain anaesthesia to T4. The addition of bicarbonate to lidocaine resulted in a mean (SD) pH increase from 6.58 (0.01) to 7.14 (0.02) and in a mean PCO2 increase from 3.8 (0.8) to 345.1 (5.9) mmHg. Onset of sensory analgesia to the S1 segment as well as the interval between the block and the delivery of the baby were shorter in the bicarbonate group (respectively 15.4 (6.9) vs 18.9 (4.8) min and 28.9 (9.5) versus 33.9 (11.8) min; P < 0.01 and 0.05). No differences were noted in the onset to T4 or in the degree of motor block. The percentage of patients experiencing pain during surgery and requiring intravenous analgesics was higher in the group which did not receive bicarbonate (3% vs 16%; P < 0.05). There were no differences in intraoperative maternal side-effects, neonatal outcome or in maternal venous and umbilical venous and arterial lidocaine concentrations between the groups. The concentrations of fentanyl in maternal plasma, umbilical artery, and the umbilical artery to maternal vein ratio were greater in the alkalinized group (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Is opioid loading necessary before opioid/local anaesthetic epidural infusion? A randomized double-blind study in labour

The effects of two different epidural loading doses administered before starting an opioid/low dose local anaesthetic infusion were examined in a randomized double-blind study during labour. Forty mothers were given either 10 ml 0.25% plain bupivacaine or 10 ml 0.125% plain bupivacaine containing 5 mcg of sufentanil followed in all cases by epidural infusion of 0.08% plain bupivacaine containing 0.2 mcg/ml of sufentanil, which was continued into the second stage. The quality of analgesia did not differ significantly between the groups in either the first or the second stage of labour: in each group 75% of women required 0 or 1 top-up during labour and verbal numerical pain scores were similar. Over 80% of women in each group reported a pain free second stage of labour. There were no differences in the mode of delivery between the groups with 60% of women in each group having a spontaneous vaginal delivery. The proportion of women with motor block increased with the duration of the epidural infusion, with no difference between the groups. There was no difference in the degree of maternal satisfaction assessed 24 hours after delivery, with 80% of women in each group awarding the maximum verbal numerical score for their satisfaction with epidural analgesia. The incidence of maternal side effects (nausea, vomiting, drowsiness and pruritus) was similar in the 2 groups as was neonatal outcome, assessed by Apgar and neurological and adaptive capacity scores and umbilical artery and vein pH. We conclude that opioid loading before opioid/low-dose bupivacaine epidural infusions is unnecessary.

Infant temperament and postpartum depression: a review

Although limited in number, reported research studies indicate a relationship between maternal perceptions of infant temperament and postpartum depression. Excessive crying in particular and the extent of adaptability and predictability have been implicated as infant behavioral indices. In this article, we present the results of a review of the literature linking early infant temperament to postpartum depression. Measurement issues for both infant temperament and depression are discussed. Recommendations for future research are offered.

Effects of omeprazole, with and without metoclopramide, in elective obstetric anaesthesia

We report the results of a study comparing two dose regimens of the gastric antisecretory agent, omeprazole, used as prophylaxis against pulmonary aspiration of gastric contents during general anaesthesia for elective Caesarean section. Since antisecretory agents do not clear stomach contents already present at the start of treatment, two groups of patients who had received both omeprazole and a prokinetic drug, metoclopramide, were also studied. Thirty patients received oral omeprazole 40 mg on the evening before and on the morning of the operation (group 1), 33 received oral omeprazole 80 mg on the morning of the operation (group 2), and 15 (group 3) and 16 (group 4) patients respectively received the oral omeprazole doses stated above and in addition metoclopramide 10 mg given intramuscularly at least 20 min before induction of anaesthesia. Gastric aspirate pH and volume were measured at induction of anaesthesia and on completion of surgery. At induction of anaesthesia, treatment was judged successful (pH > or = 2.5 and volume < 25 ml) in 87%, 73%, 100% and 81% of patients in groups 1-4 respectively. The corresponding results on completion of surgery were 100%, 88%, 100% and 100%. While omeprazole is useful as prophylaxis against pulmonary aspiration during general anaesthesia for elective Caesarean section, the addition of a prokinetic agent seems to be necessary to maximise its effects.

Neonatal effects of adding epidural fentanyl to 0.5% bupivacaine for caesarean section

Epidural injection of opioids has been introduced to improve analgesia during labour and caesarean section. This study was designed to quantify placental transfer of fentanyl and to evaluate neonatal effects of adding fentanyl to 0.5% bupivacaine for epidural anaesthesia in women undergoing elective caesarean section at term. The parturients were randomly allocated to one of four groups of 20, who received either saline (control) or 50, 75 or 100 microg of fentanyl added to 20 ml of 0.5% bupivacaine. Apgar scores, time to sustained respiration and umbilical acid-base values did not differ among the groups. The median (interquartile range) umbilical artery to maternal vein fentanyl concentration ratio was 0.34 (0.26-0.48) when the fentanyl groups were taken together. Neurologic and adaptive capacity scores were evaluated at 2 and 24 h. Neonates whose mothers received fentanyl had lower scores with regard to supporting reaction at 2 h and active tone at 24 h, when compared to controls (P<0.05), but there were no differences among the groups with regard to the other test criteria in the neurobehavioural test. In conclusion, epidural injection of fentanyl 50-100 microg did not produce depression of the term neonate.

Lidocaine hydrocarbonate and lidocaine hydrochloride for cesarean section: transplacental passage and neonatal effects

Twenty-six patients, ASA physical status 1, scheduled for elective cesarean section, were divided at random into two groups and received via an epidural catheter 20 ml of 2.2% lidocaine hydrocarbonate (17.3 mg.ml-1 lidocaine base) with 5 micrograms.ml-1 epinephrine freshly added (Group CO2 = 13 patients) or 20 ml of 2% lidocaine hydrochloride (17.3 mg.ml-1 lidocaine base) also with 5 micrograms.ml-1 epinephrine freshly added. Following clampage of the umbilical cord (at 40.1 +/- 4.9 min after the injection of lidocaine for the CO2 group and at 41.0 +/- 5.4 min for the HCl group), serum concentrations of lidocaine were measured both in the mother and in the umbilical vein. All newborns were examined by the same blinded pediatrician with Apgar scores at 1, 5 and 10 min and with Neurobehavioral Adaptive Capacity Scores (NACS) at 15 min, 2 h and 24 h. The concentrations of lidocaine in the serum were comparable in both groups: in the mothers 8.61 +/- 1.48 mumol.l-1 for the CO2 group vs 8.04 +/- 2.36 mumol.l-1 for the HCl group and in the newborns 3.86 +/- 0.84 mumol.l-1 for the CO2 group vs 3.92 +/- 0.95 mumol.l-1 for the HCl group. The ratio of umbilical vein to maternal vein concentrations of lidocaine was also similar in both groups: 0.45 +/- 0.07 for the CO2 group vs 0.54 +/- 0.24 for the HCl group. The percentage of newborns with a normal NACS (score > or = 35/40) was equal in both groups, i.e. 91% at 15 min and 2 h of life and 100% at 24 h of life.(ABSTRACT TRUNCATED AT 250 WORDS)

Respiratory function in severe gestational proteinuric hypertension: the effects of rapid volume expansion and subsequent vasodilatation with verapamil

OBJECTIVES

(1) To define the baseline respiratory function in untreated severe gestational proteinuric hypertension (GPH) and (2) to assess the effects of volume expansion with dextran (MW = 70,000 Dalton) and subsequent vasodilatation with the calcium antagonist verapamil on the baseline respiratory function in severe GPH.

DESIGN

Prospective descriptive study.

SETTING

Reproductive Research Unit, Groote Schuur Hospital, Cape Town, South Africa.

SUBJECTS

Six women with severe GPH undergoing stabilization and delivery.

INTERVENTIONS

Baseline haemodynamic and respiratory function was assessed using invasive monitoring. Patients then underwent volume expansion to a pulmonary capillary wedge pressure of 16 mmHg with dextran-70, followed by vasodilatation with the calcium antagonist verapamil. Haemodynamic and respiratory variables were measured, before and after both the fluid load and the reduction (20%) in the mean arterial pressure.

MAIN OUTCOME MEASURES

Mean arterial pressure, heart rate, mean pulmonary arterial pressure, pulmonary capillary wedge pressure, central venous pressure, cardiac index, systemic vascular resistance, pulmonary vascular resistance, respiratory rate, blood gases, alveolar arterial oxygen difference, oxygen availability, oxygen consumption, pulmonary shunt fraction.

RESULTS

Baseline oxygen availability/delivery and oxygen consumption indices were consistent with severe tissue ischaemia. Volume loading with 400 +/- 114 ml dextran-70 normalized these variables, and subsequent vasodilatation with verapamil did not reduce these indices below the normal limits for pregnancy.

CONCLUSIONS

These data support the theory that some of the complications of severe GPH may follow organ damage due to prolonged tissue ischaemia. They also support the appropriateness of controlled volume expansion in the management of this condition. We suggest, from these data, that the combination of volume expansion and verapamil vasodilatation lowers the blood pressure without compromising the maternal respiratory function.

Maternal and neonatal effects of adding epidural sufentanil to 0.5% bupivacaine for cesarean delivery

STUDY OBJECTIVE

To determine the maternal and fetal effects of the addition of epidural sufentanil to 0.5% bupivacaine for cesarean delivery.

DESIGN

Randomized, double-blind, prospective study.

SETTING

University Hospitals, Katholieke Universiteit Leuven, Leuven, Belgium.

PATIENTS

Sixty women at term scheduled for elective cesarean section, all of whom had elected epidural anesthesia.

INTERVENTIONS

The 60 women were divided into three groups of 20, with each group receiving a different 1 ml study solution: saline (control) or sufentanil 20 micrograms or sufentanil 30 micrograms added to 0.5% bupivacaine and epinephrine (1:200,000).

MEASUREMENTS AND MAIN RESULTS

In the mother, the quality of anesthesia, the duration of postoperative analgesia, the volume of anesthetic, and the frequency of side effects were examined. The neonates were evaluated at 5 and 10 minutes after birth by Apgar scores and between 60 and 120 minutes after birth by both the screening test developed by Prechtl and the Neurological and Adaptive Capacity Scoring System. Immediately after delivery, maternal and umbilical vein blood were drawn and assayed for sufentanil levels. Adding sufentanil significantly improved the quality of anesthesia without depressing the neurobehavioral status of the baby.

CONCLUSION

The epidural injection of sufentanil added to 0.5% bupivacaine with epinephrine improved the quality of anesthesia during elective cesarean section without jeopardizing the safety of the baby.

Risk-benefit assessment of anaesthetic agents in the puerperium

A critical evaluation of anaesthetic agents in the puerperium is difficult because systematic, relevant studies are still lacking. Current knowledge of the effects of different agents used in labour and caesarean section indicates that significant residual effects on the mother and newborn are limited. In the early puerperium, based on physiological and/or hormonal changes, the mother could be more sensitive to inhalational anaesthetic agents and local analgesics. To date there is no evidence that any anaesthetic agent is excreted in breast milk in clinically significant amounts when given as a single dose. The only exception is perhaps in the case of very premature neonates whose mothers have had multidrug therapy before labour. Even then the importance of breast milk should be carefully assessed against possible adverse drug effect. However, repeated administration of long-acting benzodiazepines and continuous epidural administration of pethidine (meperidine) can have adverse effects on the neonate. The essential conclusion of this review is that breast-feeding is best. The different anaesthetic agents are excreted in the milk in amounts so low that detrimental effects on the neonate should not be expected.

Residual curarization in the neonate after caesarean section

The transplacental transfer and the neonatal effects of atracurium 0.3 mg.kg-1 (ED95) were compared with those of d-tubocurarine at the usual clinical dose of 0.3 mg.kg-1 (ED90) in 46 patients undergoing elective Caesarean section. The atracurium group (25 patients) was similar to the d-tubocurarine group (21 patients) as far as age, parity and time intervals between precurarization, induction, skin incision, muscle relaxant administration, hysterotomy and birth. The transplacental transfer of atracurium was lower than that of d-tubocurarine, with a feto-maternal ratio of 9 +/- 3% for atracurium and 12 +/- 5% for d-tubocurarine (P less than 0.05). The transplacental transfer of laudanosine was low at 14 +/- 5%, with blood levels of 0.101 +/- 0.032 microM.L-1 in the umbilical vein. Newborns in the two groups were comparable in terms of Apgar scores at one, five and ten minutes, as well as for NACS scores (neurological and adaptive capacity scoring test) at two and 24 hours after birth. However, at 15 min after birth, only 55% of newborns in whom the mothers received atracurium had a normal NACS score (greater than or equal to 35/40) compared with 83% of newborns in whom the mothers received d-tubocurarine (P less than 0.05). Further analysis of the five variables related to active muscle tone revealed that the modal score for active extension of the neck of newborns from the atracurium group was lower than for newborns from the d-tubocurarine group (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Epidural mepivacaine for cesarean section: effects of a pH-adjusted solution

STUDY OBJECTIVE

To determine the clinical effects of the alkalinization of 2% mepivacaine with epinephrine used for epidural block during cesarean section.

DESIGN

Randomized, double-blind, placebo-controlled (standard commercial preparation of 2% mepivacaine with epinephrine) study.

SETTING

Inpatient obstetric department at a general hospital.

PATIENTS

Seventy patients scheduled for elective cesarean section under epidural anesthesia.

INTERVENTIONS

Two groups of 35 patients each receiving either the standard commercial preparation of mepivacaine or the pH-adjusted solution (prepared with the addition of 0.1 meq/ml of sodium bicarbonate to the standard commercial solution).

MEASUREMENTS AND MAIN RESULTS

Measurements of sensory (pinprick) and motor (Bromage's criteria) block were taken at 1- to 2-minute intervals beginning after the completion of the epidural injection. Increasing the pH of the mepivacaine resulted in a significant shortening of the time of analgesia onset (9.3 minutes compared with 16.01 minutes, p less than 0.01) and of peak effect (11.1 minutes compared with 21.2 minutes, p less than 0.01). The alkalinization did not affect duration of the block, intensity of motor block, or mean dose of local anesthetic used.

CONCLUSION

The alkalinization allowed the surgery to proceed more rapidly, significantly decreasing the time interval between epidural block and delivery of the infant.

Propofol for induction and maintenance of anaesthesia at caesarean section. A comparison with thiopentone/enflurane

A propofol infusion regimen and a standard general anaesthetic were compared in 40 Chinese women undergoing elective Caesarean section. Twenty patients received propofol 2 mg/kg for induction of anaesthesia followed by propofol 6 mg/kg/hour, while 20 patients received thiopentone 4 mg/kg with enflurane 1% for maintenance of anaesthesia. All patients were given atracurium and their lungs ventilated with nitrous oxide 50% in oxygen until delivery of the neonate. The hypertensive response after intubation was of shorter duration in the propofol group compared with the thiopentone group. Induction to delivery times ranged from 5 to 14 minutes and neonates from both groups had similar and satisfactory Apgar scores. Neurologic and Adaptive Capacity Scores and umbilical cord blood gas analysis. However, a prolonged propofol infusion time before delivery may cause lower Neurologic and Adaptive Capacity Scores. There were no differences in maternal recovery times or psychomotor performance.

[Evaluation of obstetrical pain by a questionnaire of adjectives. Comparison of 2 epidural analgesia protocols]

A French version of the McGill pain questionnaire, the "Questionnaire Douleur Saint Antoine" (QDSA), was assessed prospectively by comparing two epidural analgesia protocols using bupivacaine. One hundred women in labour who asked for epidural analgesia were randomly allocated to two groups and received either 0.25% or 0.5% bupivacaine (mean initial doses 32.5 and 50 mg respectively) with adrenaline 1 in 200,000. All the patients were then instructed to trigger a patient controlled analgesia (PCA) device for top-up doses of 0.25% bupivacaine with adrenaline 1 in 400,000 once they became aware of pain returning. This PCA device was preset to give on-demand injections of 12.5 mg with a lockout interval of 20 min, together with a continuous infusion rate of 10 mg.h-1. Pain was evaluated using four rating scales: QDSA, visual analogue scale (VAS), verbal rating scale (VRS) and behavioural scale (BS). Pain was measured at least four times: before analgesia (T0), 20 min after the initial injection (T20), before starting PCA (TRe), and immediately after delivery of the newborn (TEx). In addition, the level of anxiety was ranked at the beginning of labour with the Spielberger state trait anxiety inventory (STAI). In the 396 questionnaires completed by the patients, there was a significant correlation between the QDSA and the other scales (p less than or equal to 0.05), but at T0, BS was mostly correlated with the affective index of QDSA (p = 0.01), as well as with the STAI (p = 0.0001). At T20, in the group of women who had been given 0.5% bupivacaine initially, the decrease in QDSA score was significantly greater for the sensory index (p = 0.04); the first re-injection interval was longer than in the other group of women (p = 0.05). At TRe, the total QDSA score of all the patients was half that at T0, indicating the good sensitivity of this score. These results are in agreement with those reported by Melzack with the McGill pain questionnaire. The QDSA varies in the same direction as the other scales. On the other hand, the affective part of the score was only correlated with the level of anxiety and behaviour. The sensory part of this score was the only one to show a difference between the different initial doses given to the patients. The results obtained with this series of patients underline the value of a multidimensional assessment of labour pain.

Use of monkey neonatal neurobehavioral test batteries in safety testing protocols

Developmental neurobehavioral test batteries are important in assessing potential reproductive and developmental toxicity of new chemicals and drugs. They provide a broad-based evaluation of a range of nervous system functions at a period of life when learning and adaptation are particularly critical. Nonhuman primates are an especially appropriate test species because of their similarities to humans in complexity of brain function and prolonged intrauterine brain development. Problems arise, however, in the analysis and interpretation of data bases generated when a relatively small number of animals are tested on a relatively large number of items. A 2-week neonatal test battery for rhesus monkey infants is described along with approaches to experimental design and statistical analyses that are helpful in providing sound and useful interpretation.

Propofol infusion anaesthesia for caesarean section

Two propofol infusion regimens and a standard general anaesthetic were compared in thirty Chinese women undergoing elective Caesarean section. After induction of anaesthesia with propofol 2 mg.kg-1, ten patients received propofol 6 mg.kg-1.hr-1 and nitrous oxide 50 per cent in oxygen while ten were given propofol 9 mg.kg-1.hr-1 with 100 per cent oxygen. The other ten patients received thiopentone 4 mg.kg-1 and nitrous oxide 50 per cent in oxygen with enflurane one per cent. Maternal recovery times and psychomotor performance were recorded. Neonates were assessed by Apgar scores, neurologic and adapative capacity scores (NACS) and umbilical cord blood gas analysis. Haemodynamic changes were similar immediately following induction but the low propofol infusion group had the best haemodynamic stability subsequently. Recovery times were fastest in the low-infusion group but there were no differences in later postbox testing. Neonatal Apgar scores and umbilical blood gas analysis were similar but NACS at two hours were poorer in the high infusion group. A propofol infusion coupled with nitrous oxide appears to be a satisfactory technique for Caesarean section.

Isoflurane or halothane for cesarean section: comparative maternal and neonatal effects

The maternal and neonatal effects of isoflurane and halothane combined with 50% N2O - 50% O2 were compared in 60 healthy parturients undergoing primary or repeat cesarean section. All patients had rapid sequence induction of anesthesia with sodium thiamylal 4 mg/kg followed by succinylcholine for tracheal intubation. Patients were randomly assigned to one of three groups of 20 each (inspired 0.5% isoflurane, 1% isoflurane or 0.5% halothane), combined with 50% N2O and O2. After delivery, 67% N2O in O2 was used, supplemented by butorphanol. Maternal blood loss did not differ significantly among the three groups and none of the patients developed intraoperative awareness. At the time of delivery, maternal plasma epinephrine levels were significantly above preinduction levels in the 0.5% isoflurane group but unchanged in the other two groups. Neonatal status as ascertained by Apgar scores, cord acid base status and the Neurologic and Adaptive Capacity Scores (NACS) was equally good in the three groups of patients. Serum inorganic fluoride concentrations in the mother after anesthesia were not significantly above preanesthetic levels in any of the groups and there was no biochemical evidence of renal toxicity. In all neonates fluoride ion concentrations in the first voided urine sample were less than 7 mumol/l, a value well below that associated with nephrotoxicity. It is concluded that isoflurane is a safe supplement to N2O - O2 mixture for cesarean section and is a safer alternative to halothane in situations when patients receiving beta-adrenergic therapy require cesarean section since halothane might potentiate arrhythmias caused by beta adrenergic agonists.

Fentanyl citrate analgesia during labor

Fentanyl citrate is a potent short-acting narcotic reported to cause less nausea and sedation than morphine or meperidine hydrochloride. The purpose of this prospective investigation was to determine whether a safe but adequate intrapartum dosing schedule is possible. A total of 137 women with uncomplicated term pregnancies were offered a standard intravenous dose (50 mcg or 100 mcg hourly as needed) of fentanyl citrate during active labor. Temporary analgesia and mild sedation were apparent in each case. The cumulative dose varied in accordance with maternal needs (mean, 140 +/- 42 micrograms; range, 50 mcg to 600 micrograms). Apart from a brief decrease in fetal heart rate variability that lasted 30 minutes, no worrisome pattern was apparent from exposure to fentanyl citrate. Pediatric examinations were performed without knowledge of analgesic therapy on infants exposed to fentanyl citrate and those not exposed to analgesics. No differences were found in frequencies of newborn depressed respirations, low Apgar scores, or neurologic and adaptive capabilities at two hours and 24 hours postnatally. With the use of the described dosing schedule, fentanyl citrate was helpful during labor and did not cause immediate or prolonged hazards to the mother and unborn infant.

Comparison of the effects of general and epidural anaesthesia for caesarean section on the neurobehavioural responses of newborn infants

Thirty-one neonates delivered by elective caesarean section were evaluated at the ages of 3 h, 1 day, 2 days and 4-5 days using Scanlon's Early Neonatal Neurobehavioural Scale and tests for orientation. Thirteen of the mothers received general anaesthesia and 18 epidural anaesthesia. All the mothers were healthy and not in labour. All the neonates weighed 2500 g or more and had Apgar scores of 7 or more at 1, 5 and 15 min. The neonates delivered with epidural anaesthesia scored significantly lower on rooting at the age of 3 h than those delivered with general anaesthesia, but the latter scored significantly lower on habituation to sound and orientation to both animate and inanimate visual stimuli. General anaesthesia seemed to depress the infants' interactive processes (orientation items), and their ability to make an appropriate response to repetitive stimuli (habituation) more than did epidural anaesthesia, indicating greater global depression. This depression was short-lived, however, and there were no differences between the groups on any of the parameters after 24 h.

The effect of lumbar epidural analgesia on the neurobehavioural responses of newborn infants

The effects of maternal lumbar epidural analgesia (Th10-L5) on the neonatal neurobehavioural response were studied at the ages of 3 h, 1 day, 2 days and 4-5 days. The subjects were healthy, full-term neonates, born vaginally to 15 mothers with lumbar epidural block and 19 mothers without analgesia. Those delivered with epidural analgesia scored significantly better on alertness at the age of 3 h, 2 days and 4-5 days than the control group. No other statistically significant differences were found between the groups. The formation of the two groups according to the mothers' desire for epidural analgesia may have contributed to differences in the process of labour, but with this reservation it may be suggested that lumbar epidural analgesia may enhance the infant's recovery from the stress of labour and vaginal delivery.

Epidural fentanyl plus bupivacaine 0.125 per cent for labour: analgesic effects

Ninety-five healthy nulliparous women, ASA physical status I-II with an uncomplicated pregnancy and single fetus in vertex position were given lumbar epidural analgesia. Patients in Group A (n = 35) received bupivacaine 0.125 per cent with epinephrine 1:800.000; Groups B (n = 30) and C (n = 30) received the same agents as Group A but with the addition to the initial dose of 50 or 100 micrograms of fentanyl respectively. All patients were evaluated for duration and quality of analgesia, duration of labour, method of delivery and total dose of bupivacaine used. The addition of either 50 or 100 micrograms of fentanyl resulted in longer duration of analgesia (93 +/- 9 min and 106 +/- 8 min respectively vs 55 +/- 7) and reduced bupivacaine total doses (64 +/- 0.03 and 55 +/- 1.5 respectively vs 109.5 +/- 1.3). Only the addition of 100 micrograms of fentanyl improved significantly the quality of analgesia (43.3 per cent of excellent scores vs 6.6 per cent in Group B and 5.7 per cent in Group A). Addition of fentanyl did not affect the duration of labour, the method of delivery and the neonatal neurobehaviour scores.

Nalbuphine for obstetric analgesia. A comparison of nalbuphine with pethidine for pain relief in labour when administered by patient-controlled analgesia (PCA)

A double-blind, randomised study of 60 patients who received intravenous increments of nalbuphine 3 mg or pethidine 15 mg by patient-controlled analgesia during the first stage of labour, was carried out. Pain intensity, sedation, uterine contractions, maternal cardioventilatory variables and fetal heart rate were recorded as well as any side effects. Apgar scores, time to sustained respiration and resuscitative measures required for the neonate were noted at delivery. Modified neonatal neurobehavioural studies and a retrospective assessment of maternal analgesia, satisfaction and tolerance were also carried out. Group mean values of pain scores of nalbuphine-medicated primiparous women were statistically significantly lower than those of pethidine-medicated patients (p less than 0.01). Other assessments did not demonstrate a statistical significance between the two groups.

Placental transport of metoclopramide: assessment of maternal and neonatal effects

Twenty-three patients undergoing general anaesthesia for Caesarian section for healthy term pregnancies were entered into a double blind study using metoclopramide (MCP) and a normal saline placebo. Of these patients, eight received intravenous metoclopramide, 12 a normal saline placebo and three were lost to clinical follow-up. The maternal gastric volumes were measured and maternal and foetal MCP plasma concentrations were determined by gas-liquid chromatography. The Neurological and Adaptive Capacity Score tests of Amiel, Barrier and Schnider (NACS) were used to attempt evaluation of neonatal responses to MCP. Maternal gastric volume was significantly lower (p less than 0.05) in the treated patients. There were no marked differences in Apgar scores, cardiovascular parameters or neurobehavioural scores between the treated and untreated groups of neonates. At no time were the foetal metoclopramide plasma concentrations observed to exceed maternal values.