External cephalic version with epidural anaesthesia after failure of a first trial with beta-mimetics

Authors


Correspondence: Dr P. Rozenberg, Centre hospitalier intercommunal Léon Touhladjian, Rue du Champ Gaillard, 78303 Poissy Cédex, France.

Abstract

Objective To assess the efficacy, tolerance, and cost of external version under epidural anaesthesia and beta-mimetic tocolysis after the failure of an initial attempt with tocolysis alone.

Design Prospective open study.

Participants Sixty-eight women with breech presentation at around 36 weeks of gestation and an attempted external cephalic version under salbutamol that failed, who consented to try a second attempt under epidural anaesthesia.

Results The overall success rate under epidural anaesthesia was 39.7% (27/68), and complications occurred in two cases. The total cost of attempting external version was higher than the cost of expectant management.

Conclusions The efficacy of external cephalic version under epidural reduces the rate of caesarean sections associated with breech presentation, but its relative safety remains in question. Moreover, our economic analysis discourages the hope of lowered costs suggested by earlier reports that this technique is more expensive than expectant management, except in institutions with a policy of systematic caesarean sections when version fails.

INTRODUCTION

Fetuses presenting by the breech have higher rates of neonatal morbidity and mortality than do fetuses with a cephalic presentation1. In the US, between 75% and 100% (depending on the hospital) of women with breech presentation at term give birth by caesarean delivery. Breech presentation accounts for 15% of all caesarean sections and costs $1.4 billion annually in the US2. Term breech presentation represents 8.1% of all indications for caesarean sections in our department. It has now been clearly shown that an attempt at external cephalic version at term can reduce the frequency of breech presentation and the rate of caesarean sections performed for this indication3. Several randomised placebo-controlled trials have shown that the success rate of external version is higher when performed with beta-mimetics4–7. External version under epidural anaesthesia has been proposed to improve the success rate, since it would reduce the pain and anxiety associated with the procedure as well as contribute to reducing abdominal and perhaps uterine muscle tone8. A prospective randomised trial9 reported that epidural anaesthesia and a tocolytic agent were better than tocolysis alone.

Nonetheless, if this type of trial is important methodologically, its practical interest is limited. Systematic use of epidural anaesthesia before every attempt at version would expose all of these patients to the complications of anaesthesia and would increase costs, when beta-mimetics alone would be sufficient in at least half of all cases4,7. For this reason we performed a pragmatic prospective trial to examine the efficacy, tolerance, and cost of external version under epidural anaesthesia and beta-mimetic tocolysis after the failure of an initial attempt with tocolysis alone.

METHODS

This prospective study took place between October 1995 and March 1998 in the Obstetric-Gynaecology Department of the Poissy Hospital Centre. During this period, external version during intravenous salbutamol (200 μg in 30 minutes) was offered to patients with a breech presentation between weeks 36 and 37. The following exclusion criteria were applied: placenta previa, premature rupture of the membranes, prior caesarean section or signs of fetal distress. An ultrasound examination verified the presentation, localised the placenta, and assessed the quantity of amniotic fluid. We did not estimate fetal weight before the version. A 30-minute cardiotocograph nonstress test (NST) then monitored fetal wellbeing (reactive NST). External version was then attempted in the labour area under ultrasound monitoring. The forward roll technique was tried twice. If it was unsuccessful, a backward roll was tried. Whether or not the version succeeded, a nonstress test was repeated for 30 minutes after the procedure. Women who were Rhesus factor-negative were given Rhesus factor immune globulin. If the manoeuvre succeeded and if neither regular and painful uterine contractions nor signs of acute fetal distress were observed, the woman was discharged to await spontaneous labour. If it failed, a new attempt during the following week was offered, following the same protocol but including an epidural.

Each woman was instructed not to eat or drink after midnight and routine preparation for caesarean section were undertaken in case fetal distress occurred. Ringer Lactate (1500 mL) was given intravenously, and an epidural catheter was placed at the level of L2–L3 or L3–L4, using the standard technique. The initial dose was 2 mL of lidocaine 2%, followed by a 3 mL bolus of the same solution every ten minutes thereafter, to obtain a sensitive symmetric block greater than D10, accompanied by the onset of motor blockade (Bromage score > 2). Electrocardiograph, oxygen saturation, and blood pressure were monitored continuously. Hypotension was corrected by a 3 mg bolus of intravenous ephedrine. After these manoeuvres, the patient was monitored until complete recovery from the motor block and was then allowed to return home to await either spontaneous labour or an elective caesarean section. This study was conducted in accordance with the guidelines of the Poissy Hospital Committee on Medical Ethics and Human Experimentation.

Statistical analysis

A χ2 test was used to compare percentages, and a Student's t test was used to compare the means between the groups. We use odds ratios with their 95% confidence intervals to present the comparison between the groups (Mantel-Haenszel)10.

Economic analysis

Costs were computed from the viewpoint of the hospital and included only medical costs; we excluded social tangible and intangible costs. Costs were computed for the initial admission and exclude the costs of subsequent hospitalisations and complications after discharge. Costs were computed in French francs at the 1998 rate (1 £= 10 FF). The following costs associated with obstetrical procedures were considered:

  • 1Pro rata of annual gross wages of medical and non-medical personnel plus employers' payroll taxes.
  • 2Purchase price of medical supplies.
  • 3Purchase price of drugs.
  • 4For laboratory tests, imaging, and monitoring procedures we used an average cost of the hospital computed using the national weighing system and local costs in the technical departments.
  • 5Equipment, in the delivery room and elsewhere was estimated assuming a 10-year straight line amortisation of purchase price, plus maintenance, divided by the total number of procedures performed annually.
  • 6An overhead of 25% was added to all costs.

We used accounting sheets provided by the hospital administration and the activity data from the clinical and technical departments to cost these procedures. The cost of each strategy was computed by multiplying the cost of an event (external cephalic version, normal delivery, caesarean section) by the probability of its occurrence.

We performed an alternative cost analysis taking into account that some hospitals have a policy of routine caesarean delivery for breech presentation. Using our data on effectiveness of external cephalic version (initial or repeated), we computed the average cost for a patient with attempted cephalic version by weighting the cost of each procedure according to the likelihood of its occurrence and comparing it with the cost of a routine caesarean section in all cases where version fails.

The total cost of an admission was computed by adding the cost of hospitalisation, estimated from the daily cost and average length of stay, to the total cost of the procedures. We also used the French system of diagnosis-related groups to obtain an alternative cost estimate. In 1998, this system was not used for reimbursement purposes but only to compare hospital activities and budgets, with hospital budgets still fixed on a cost-plus basis11–15.

RESULTS

During the study period, 5453 births were recorded. Breech presentations were observed around 36 weeks of gestation in 171 (3.1%). All but two women agreed to undergo an attempt at external cephalic version under salbutamol. Version succeeded in 56.8% (96/169). A second attempt under epidural anaesthesia was agreed by 68 of the remaining 73 patients. The general and obstetric characteristics of these 68 women are summarised in Table 1.

Table 1.  General characteristics of the population. Values are given as mean (SD) or % [n/n]. GA = gestational age; ECV = external cephalic version.
Maternal age (years)28.6 (3.8)
Nulliparae72 [49/68]
Weight (kg)72.1 (10.4)
GA at ECV (weeks)37.7 (0.8)

The global success rate under epidural anaesthesia was 39.7% (27/68). The epidural anaesthesia was ineffective in one case, and version was unsuccessful because of pain. Complications occurred in two cases; one case of inadvertent dural puncture was treated by epidural bloodpatch and one case of moderate bleeding occurring the day after the version (after spontaneous labour, a 3380 g infant was delivered vaginally who had an Apgar score of 8/10 and an artery pH 7.26; examination of the placental found a marginal haematoma). There were no cases of fetal distress, or placental abruption, or of reversion to breech after successful cephalic version under epidural. Finally, no fetus spontaneously reverted to vertex after an unsuccessful external cephalic version.

The success rate was 68.4% among multiparas compared with only 28.6% among nulliparas (P= 0.002). Maternal overweight, on the other hand, was a negative factor. Women weighing ≥ 70 kg had a success rate of only 36% compared with 64% for women weighing < 70 kg (P= 0.004). The type of presentation also had an effect near the limits of statistical significance. The success rate for incomplete breech presentations was 42% compared with 15.4% for those with a complete breech presentation (P= 0.07). In contrast, placental position seemed to have no effect on the external cephalic version under epidural (P= 0.9).

The obstetric and neonatal results for women according to whether the external cephalic version was successful are shown in Table 2. The group with successful version had a significantly lower rate of caesarean delivery (7.4% or 2/27) than the group among whom version failed (46.3% or 19/41; P= 0.0007). All newborns in both groups had a 5-minute Apgar score of at least 7. One child in the successful version group and two in the ‘failure’ group were transferred to neonatal intensive care. The first child required monitoring and antibiotic treatment for chorioamnionitis. One of the other two had transitory respiratory distress following acute fetal distress that led to an emergency caesarean section (1-and 5-minute Apgar scores 1 and 8 respectively, umbilical pH 7.28) but was transferred to the regular nursery in good condition 24 hours later. The third child had intrauterine growth restriction at 37 weeks. Although this is normally a contraindication to external cephalic version, we felt that the attempt could be made, in view of the normal fetal heart rate, biophysical profile, and amniotic fluid index. This attempt was unsuccessful. We then decided to induce labour with oxytocin (because of the intrauterine growth restriction), leading to the vaginal delivery of a 1850 g boy (1- and 5-minute Apgar scores 8 and 10, respectively). He was transferred to neonatal intensive care because of the intrauterine growth restriction.

Table 2.  Obstetric outcome according to result of external cephalic version (ECV) attempted with epidural anesthesia. Values are given as n (%) or mean [SD], unless otherwise indicated.
 ECV success (n= 27)ECV failure (n= 41)POR (95% CI)
Caesarean sections2 (7.4)19 (46.3)0.00070.09 (0.02–0.37)
1 minute Apgar < 71 (3.7)13 (31.7)0.0050.08 (0.01–0.48)
pH < 7.203 (11.1)4 (9.7)0.851.16 (0.24–5.62)
Birthweight (g)3181 [315]3207 [506]0.81
Length of hospitalisation (days)4.6[1.3]5.4[1.5]0.04

According to the hospital's cost-accounting systems, the total cost of a birth with successful external cephalic version was 22,308 FF and for a birth following unsuccessful external cephalic version, 25,954 FF. Based on the mean prevalence of caesarean sections for breech presentations (75%) and on the French diagnosis-related groups, we can assess the mean cost of the delivery if a second external cephalic version with epidural is not attempted as 21,187 FF. Itemised costs are detailed in Table 3.

Table 3.  Economic analysis. Costs in French francs (FF) as calculated by the hospital's accounting system and estimated according to the diagnosis-related groups (DRG) system.
 Costs (FF)
ProceduresHospital accounting systemDRG estimated
  1. *No external cephalic version.

Peridural anesthesia2880
Caesarean section10,500
External cephalic version2608
Delivery room costs  
Per normal delivery*2100
Per day168
Maternity ward costs per day1807
Total costs  
Normal delivery*16,65215,300
Caesarean section23,13823,149
Successful external cephalic version22,30822,093
Failed external cephalic version25,93826,003

The average cost with attempted cephalic version was computed for initial or secondary success in respectively 57% and 16% cases, and failure rate of 27%. By weighing the total cost in each category by the corresponding probability we found an average weighted cost of 13,024 FF which compares favourably with the 23,138 FF cost of routine caesarean sections, without any trial of labour.

DISCUSSION

Use of epidural anaesthesia led to an increase in the total success rate of external cephalic version from 56.8% to 72.8% (123/169), most likely by eliminating — or substantially reducing — the pain and anxiety generated by these manoeuvres. This series, which is the largest so far reported on the subject, confirms the results previously published by Carlan et al.8 and Schorr et al.9 about the efficacy of this technique. Our success rate under epidural is lower than theirs because our two-step procedure used epidural only for a population for which an external cephalic version with salbutamol had already failed.

We chose to perform this second attempt at a younger gestational age than in the studies by Carlan et al.8 and Schorr et al.9 to optimise the possibility of success, since we were dealing with a selected population for whom the anticipated failure rate was high. This choice is only justified, of course, when vaginal delivery is not excluded if version fails. Otherwise, it would be wiser to try version later in gestation with a caesarean section planned for immediately afterwards (as in the study by Schorr et al.9), to benefit from the epidural even if the version fails.

Although it is very probable that the reduction in the rates of caesarean deliveries after external cephalic version with epidural is linked to the efficacy of this technique, we cannot be positive. Certainty could be provided only by a comparative study with a control group in which no external cephalic version with epidural analgesia was performed.

While the efficacy of this procedure is now clear, its safety cannot yet be prudently affirmed. The aggressive manipulation made possible by analgesia may increase the risk of Rhesus iso-immunisation, placenta abruptio, prolapsed cord, premature rupture of membranes, and rupture of the uterus. Moreover, during epidural analgesia, the incidence of dural puncture has been estimated at between 0.4% to 5%16. In half of these, headache following the tap will be severe or incapacitating and may thus require a prophylactic epidural bloodpatchl17. Although the two complications in our study ended well, the marginal placental separation could have had a more dramatic outcome. Nonetheless, in all the versions under epidural so far reported8,9,18,19, there has been only one accident among 160 patients; a case with an abruptio placenta reported by Carlan et al.8. The incidence of this complication, however, was the same as in the group that underwent attempted external cephalic version without epidural. Overall, although the possible morbidity of this technique is probably low, it must be evaluated more precisely by larger trials.

The risks could be minimised by delaying the attempt at external cephalic version with regional analgesia until the onset of spontaneous labour or planned labour induction, so that the fetal condition could be monitored continuously from the time of the procedure through delivery. This approach has previously been suggested as a method to reduce the risk of external cephalic version without regional analgesia20. The disadvantage is that the opportunity to attempt external cephalic version would be lost if the membranes ruptured before attempted external cephalic version was attempted.

The assessment of the possible morbidity of this technique is all the more essential since two recent publications have concluded that vaginal delivery of term infants with breech presentation is associated with higher risks of neonatal mortality and morbidity than elective caesarean delivery. Both articles involved retrospective cohort studies; the US report21 considered 371,692 births and the Swedish study22 15,818 births. If larger prospective trials clearly show a very low morbidity rate, external cephalic version under epidural attempted immediately before elective caesarean delivery could partly compensate for the increased rate of elective caesarean section recommended by these authors.

We preferred to use epidural rather than spinal analgesia for several reasons. First, the haemodynamic effects of spinal analgesia are earlier and sharper than those of epidural analgesia23. This is all the more important as version manoeuvres are accompanied by an increase in the vena cava compression syndrome caused by the operator directly compressing the pelvic venous flow and aggravated by the need for the woman to remain in a dorsal decubitus position during the version. In addition, one of the measures to prevent a haemodynamic effect on the central block involves keeping the upper level of the block below D5. Under epidural analgesia, it is easy to control the upper level precisely, by injecting local anaesthesia by successive bolus doses, while under spinal analgesia, it is more difficult to foresee this level (which is most often above D4, especially at the end of pregnancy)24. Finally the epidural catheter can be used if caesarean delivery or induction of labour manoeuvre

Other methods have also been proposed to try to increase the success rates of external cephalic version. General anaesthesia was abandoned after the publication of several trials that observed an overall fetal mortality rate of 1%20. A bolus injection of hexoprenaline can be a very effective tocolytic25. More recent proposals include transabdominal amnioinfusion26 or nitroglycerin (which also appears to be an efficacious tocolytic agent)27. Because these latter treatments have been tested in only small series, no conclusion is possible as to either their efficacy or their safety for fetus or mother.

The total cost of attempting external cephalic version is higher than the total cost of not attempting it. It does, however, avert a number of caesarean deliveries and thus improves the mother's quality of life. Thus a cost interpretation may be misleading and additional information about quality of life should be collected to document the nonmonetary nature of the gain from avoided caesarean sections. In those institutions where caesarean sections are systematically performed for breech presentations, however, without any trial of labour, substantial savings are possible.

Although the efficacy of external cephalic version under epidural does reduce the rate of caesarean deliveries associated with breech presentation, the relative harmlessness of such a manoeuvre under epidural remains questionable, especially in view of the two complications that occurred in our series, the largest so far. For this reason we think that it would be premature to introduce this technique into routine practice: it must continue to be tested in large scale trials in order to clarify the morbidity associated with this new technique. Moreover, our economic analysis discourages the hope of lowered costs raised by earlier reports: this technique is more expensive than expectant management. This excess cost, however, need to be balanced by benefits to the newborn and with improvement of the mother's quality of life related to vaginal rather than surgical delivery. However, in those institutions where caesarean sections are systematically performed for breech presentations, substantial cost-savings are possible

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