A randomised controlled trial of fluid pre-loading before low dose epidural analgesia for labour. Comparison of combined spinal-epidural and low dose epidural for labour analgesia. Randomized study of intravenous fluid preload before epidural analgesia during labour. Regional analgesia in early active labour: combined spinal epidural vs. epidural. Effect of low-dose mobile versus traditional epidural techniques on mode of delivery: a randomised controlled trial. A randomized study of combined spinal-epidural analgesia versus intravenous meperidine during labor: impact on cesarean delivery rate. Combined spinal epidural anaesthesia for caesarean section: a randomised comparison of Oxford, lateral and sitting positions. [Obstetric analgesia: peridural analgesia versus combined spinal and peridural analgesia]. Adverse effects of combined spinal-epidural versus traditional epidural analgesia during labor.
Preloading with fluid is recommended before regional block in labour. Low dose epidurals may produce less haemodynamic disturbance than traditional stronger solutions of local anaesthetics. Our aim was to compare the incidence of hypotension in normal labouring women who received a low dose epidural (0.1% bupivacaine 15 mL with fentanyl 2 microg microg.mL(-1)) with and without an i.v. crystalloid preload. Women with normal labours were randomised to the intervention group: no i.v. crystalloid preload (n = 85) and the control group: 7 mL mL.kg(-1) i.v. crystalloid solution before epidural injection (n = 83). Mean arterial pressure was recorded every 5 min for 30 min. There was no difference between the groups in mean decrease in mean arterial pressure and similar proportions of women showed falls in mean arterial pressure of 20% or greater (13% vs. 11%, risk ratio 1.2, 95% CI 0.54 to 2.8, P = 0.6). Blinded analysis by independent obstetricians revealed no differences in the fetal heart rate abnormalities (20% vs. 15%, risk ratio 1.3, 95% CI 0.67 to 2.7). A scientifically valid conclusion whether preloading is useful cannot be drawn from this study. This study suggests that about 350 participants in each group would be necessary to exclude a type 2 error in a future study. To compare the combined spinal-epidural (CSE) technique with the epidural technique with regard to time to initiate and manage, motor block, onset of analgesia and satisfaction during labour.
                Upon requesting analgesia, 50 healthy term parturients were randomized in a prospective, double-blind fashion to receive either CSE analgesia or lumbar epidural analgesia in the labour floor of a university hospital at an academic medical centre. The epidural group (n = 24) received bupivacaine 0.0625%-fentanyl 0.0002% with 0.05 ml in 10 ml local anesthetic sodium bicarbonate 8.4% and epinephrine 1:200,000. The CSE group (n = 26) received intrathecal 25 microg fentanyl and 2.5 mg bupivacaine. Additional analgesia was provided upon maternal request.
                There were no differences (P>0.05) in time to perform either technique, motor blockade, or parturient satisfaction or in the number of times that the anesthesiologist was called to perform any intervention. Although the first sign of analgesia was not different between the two groups, the onset of complete analgesia was more rapid with the CSE technique (Visual Analogue Pain Score (VAPS) at five minutes < three: 26/26 vs. 17/24, P+/-0.001).
                Although epidural analgesia with a low concentration of local anesthetic and opioid mixture takes longer to produce complete analgesia, it is a satisfactory alternative to CSE. We performed a randomized controlled trial of the effect of intravenous fluid preload on maternal hypotension and fetal heart rate (FHR) changes in labour after the first epidural injection. Group 1 (49 women) received 1 litre of crystalloid preload. Group 2 (46 women) received no preload. No statistically significant difference was shown between the two groups for either of the outcomes. Hypotension was found in three women in group 1 and five in group 2 (P = 0.4). Deterioration in FHR pattern was found in four women in group 1 and 11 in group 2 (P = 0.08). This study has not shown a significant increase in the incidence of hypotension when intravenous preload is omitted before epidural analgesia using a low concentration of bupivacaine during labour. Because of the clinical importance of the difference in the rate of FHR deterioration between the two groups, we continue to administer preload for high-risk cases. We randomly allocated 93 women in early active labour and requesting epidural analgesia to receive either epidural (n = 48) or combined spinal-epidural analgesia (n = 45). For epidural analgesia 15 ml of bupivacaine 0.1% with 75 micrograms of fentanyl were injected into the epidural space. For combined spinal-epidural analgesia 1 ml of bupivacaine 0.25% with 25 micrograms of fentanyl were injected into the subarachnoid space. For both groups subsequent top-ups of 10 ml of bupivacaine 0.1% with fentanyl 20 micrograms were given using a lightweight patient-controlled epidural analgesia (PCEA) pump with a lockout time of 30 min. We assessed analgesia and the degree of motor blockade and found no significant differences in pain or maternal satisfaction scores between the two groups. The time to first top-up was significantly longer in the epidural group than in the CSE group (p = 0.01). The combined spinal-epidural group had significantly greater motor blockade at 30 min than the epidural group (p = 0.01), but there was no difference after this. The PCEA machine failed completely twice and temporarily many times. We conclude that the combined spinal-epidural technique confers no advantages in early active labour. Also, a lightweight PCEA pump needs to be more reliable before we can recommend its use. Epidural analgesia is the most effective labour pain relief but is associated with increased rates of instrumental vaginal delivery and other effects, which might be related to the poor motor function associated with traditional epidural. New techniques that preserve motor function could reduce obstetric intervention. We did a randomised controlled trial to compare low-dose combined spinal epidural and low-dose infusion (mobile) techniques with traditional epidural technique.
                Between Feb 1, 1999, and April 30, 2000, we randomly assigned 1054 nulliparous women requesting epidural pain relief to traditional (n=353), low-dose combined spinal epidural (n=351), or low-dose infusion epidural (n=350). Primary outcome was mode of delivery, and secondary outcomes were progress of labour, efficacy of procedure, and effect on neonates. We obtained data during labour and interviewed women postnatally.
                The normal vaginal delivery rate was 35.1% in the traditional epidural group, 42.7% in the low-dose combined spinal group (odds ratio 1.38 [95% CI 1.01-1.89]; p=0.04); and 42.9% in the low-dose infusion group (1.39 [1.01-1.90]; p=0.04). These differences were accounted for by a reduction in instrumental vaginal delivery. Overall, 5 min APGAR scores of 7 or less were more frequent with low-dose technique. High-level resuscitation was more frequent in the low-dose infusion group.
                The use of low-dose epidural techniques for labour analgesia has benefits for delivery outcome. Continued routine use of traditional epidurals might not be justified. Combined spinal-epidural (CSE) analgesia produces rapid-onset pain relief and allows ambulation in early labor. Epidural local anesthetics may contribute to an increase in operative deliveries by decreasing perineal sensation and causing motor weakness. Operative delivery rates might be reduced with CSE, by avoiding or delaying administration of local anesthetics. This study compares the operative delivery rates associated with a CSE technique and those associated with intravenous meperidine for labor analgesia.
                Healthy parturients at full term were assigned randomly to receive CSE or intravenous meperidine analgesia. The CSE group received 10 microg intrathecal sufentanil, followed by epidural bupivacaine and fentanyl at their next request for analgesia. Parturients receiving intravenous meperidine had 50 mg on demand (maximum, 200 mg in 4 h). Labor and delivery outcomes in both groups were recorded and compared.
                An intent-to-treat analysis of 1,223 women indicated that CSE does not increase the rate of cesarean delivery for dystocia in nulliparous and parous women (CSE, 3.5% vs. intravenous meperidine, 4; P=not significant) or in nulliparous women alone (CSE, 7% vs. intravenous meperidine, 8%; P=not significant). Profound fetal bradycardia that necessitated emergency cesarean delivery within 1 h of the time the mother received sufentanil occurred in 8 of 400 parturients (compared with 0 of 352 who received meperidine; P < 0.01). However, the method of fetal monitoring differed between the two groups. Despite this, neonatal outcomes were similar overall.
                Combined spinal-epidural analgesia during labor does not increase the cesarean delivery rate for dystocia in healthy parturient patients at full term, regardless of parity. However, an unexpected increase in the number of cesarean deliveries for profound fetal bradycardia after intrathecal sufentanil was observed. Further investigation is warranted. Maternal position during induction of intrathecal anaesthesia for caesarean section influences block height and haemodynamic stability. In a randomised study of 90 women presenting for elective caesarean section using combined spinal-epidural anaesthesia, three positions were compared--the Oxford position (group O), the right lateral to supine wedged (group R) and the sitting to supine wedged (group S). Hyperbaric bupivacaine 12.5 mg with fentanyl 12.5 microg was injected intrathecally using a needle-through-needle CSE technique. Intravenous ephedrine 6 mg was given every minute that systolic blood pressure fell below 80% of baseline. Time required for block height to reach T5 as assessed by light touch, was similar in the three groups. There were no significant differences in blood pressure although ephedrine requirements were less in group R. There were no significant differences in the incidence of maternal nausea and vomiting or in neonatal outcome as assessed by Apgar scores and umbilical cord blood gas analysis. Although the study failed to show any significant differences in block height between the groups, no women in group O had a block above T2 compared with three in group R and three in group S. To compare the analgesic efficiency, side effects and obstetrical repercussions of epidural analgesia (EP) and combined spinal-epidural analgesia (CSE).
                Prospective, randomized, double or single-blind studies as required, approved by the ethical committee of the institution.
                The study included 80 parturients, in active labour with a singleton in vertex presentation and a cervical dilatation of 3 cm or less, randomly allocated to receive either EP (n = 40) or CSE (n = 40).
                In the EP group, sufentanil (20 micrograms) and 0.25% bupivacaine (6-8 mL) were injected into the epidural space. In those of the CSE group, sufentanil (10 micrograms) was first injected into the subarachnoid space, followed by an epidural injection of the same agents at the same quantities as for the EP group. Additional analgesia was obtained in both groups by top-ups of 6-8 mL of 0.25% bupivacaine at the request of the patients. Analgesia, course of labour, obstetrical outcome, and neonatal status were assessed. Statistical analysis was performed using Anova, chi 2 analysis, Yates' correction or Fisher's exact test, with a P < 0.05 considered as significant.
                Both groups had similar demographic and obstetric data. The onset of analgesia was more rapid in CSE group (8 +/- 11 min vs. 12 +/- 7 min, P < 0.05), however the duration was similar. Technical incidents were more frequent in the CSE group (30% vs. 7%, P < 0.05). The technique of analgesia did not influence the bupivacaine amounts required for its maintenance. The incidence of adverse effects were comparable with the exception of vertigo, which was more frequent in the EP group (57% vs. 28%, P < 0.05). The first stage of labour was increased by 30% in the CSE group (281 +/- 130 min vs. 216 +/- 97 min, P < 0.05), without significant prolongation of labour length. Durations of second stage and expulsion were similar in both groups, despite the administration of a lower dose of bupivacaine in the CSE group (33 +/- 17 mg vs. 46 +/- 12 mg, P < 0.05). The rates of instrumental deliveries and Caesarien sections were comparable. The Apgar scores were satisfactory at 5 min.
                In the early phase of labour, the CSE technique using intrathecal sufentanil has no significant benefit when compared to the EP technique using bupivacaine and sufentanil. In the CSE group, technical incidents were more frequent and the length of the first stage of labour was increased. To compare two neuraxial block techniques during labor for maternal and fetal effects.
                Women in labor at term with cephalic singleton fetuses were randomized (nonblinded) to receive either labor epidural (EPI) or combined spinal-epidural (CSE) analgesia. Primary outcome was prolonged deceleration (PD) of fetal heart rate. Outcomes also included hypotension, mode of delivery, and efficacy of analgesia by visual analog pain scale (VAPS) before and after block placement.
                Randomization occurred in 127 patients: 63 received EPI, 64 received CSE. There was no difference in the rate of PD in the EPI group compared with the CSE group (3.2% vs 6.2% respectively; P=0.43, RR 2.0; 95% CI 0.4-9.3), rate of cesarean delivery, or mean epidural duration. VAPS ratings were significantly lower in the CSE group.
                There were no differences in the rate of PD or other adverse outcomes. Hypotension occurred more frequently with CSE during labor at term. The study supports both EPI and CSE during labor as safe and effective techniques for neuraxial analgesia.
Preloading prior to traditional high-dose local anaesthetic blocks may have some beneficial fetal and maternal effects in healthy women. Low-dose epidural and CSE analgesia techniques may reduce the need for preloading. The studies reviewed were too small to show whether preloading is beneficial for women having regional analgesia during labour using the lower-dose local anaesthetics or opioids. Further investigation of low-dose epidural or CSE (including opioid only) blocks, and the risks and benefits of intravenous preloading for women with pregnancy complications, is required.
[Note: The five citations in the awaiting classification section of the review may alter the conclusions of the review once assessed.]