Patient-controlled analgesia for labour using remifentanil: a feasibility study

Comparative efficacy of opioid and non-opioid analgesics in labor pain management: A network meta-analysis

BACKGROUND

Effective labor pain management is crucial for parturient well-being, as it can improve the delivery experience of pregnant women and reduce anxiety and tension. This systematic review and network meta-analysis compared the efficacy and safety of various analgesics, classified by drug category and individual treatment methods, for labor pain control.

METHODS

A comprehensive literature search was conducted in Pubmed, EMBASE, Cochrane Library, and Web of Science databases. All searches commenced from the database's inception to the date of the literature search (May 31, 2023). The Cochrane Risk of Bias 2 tool assessed study bias risk. Network meta-analyses using a random-effects model and odds ratios (ORs) with 95% confidence intervals (CIs) were performed.

RESULTS

Fifteen randomized controlled trials evaluating analgesic interventions in ASA I or II parturients were included. Combination therapies (OR: 5.81; 95% CI, 3.76-7.84; probability: 60%) and non-opioid analgesics (OR: 5.61; 95% CI, 2.91-8.30; probability: 39.2%) were superior to placebo for labor pain relief. Specifically, dexmedetomidine/ropivacaine/sufentanil (OR: 7.32; 95% CI, 2.73-11.89; probability: 40.6%) and dexmedetomidine/ropivacaine (OR: 6.50; 95% CI, 2.51-10.33; probability: 11.9%) combinations, bupivacaine/fentanyl and ropivacaine/sufentanil combinations, and remifentanil monotherapy showed improved analgesic efficacy versus placebo. Dexmedetomidine/ropivacaine reduced parturient nausea and vomiting versus alternatives.

CONCLUSION

Non-opioids, opioids and combinations thereof effectively relieved labor pain. In addition, dexmedetomidine/ropivacaine combination demonstrated analgesic efficacy and lower nausea and vomiting incidence.

Remifentanil at a Relatively Elevated Dose in Active Phase is Safe and More Suitable Than Fixed Lower Dose for Intravenous Labor Analgesia

Background

Intravenous labor analgesia is recommended as an alternative for parturients who have contraindications to epidural analgesia. There are several opioid analgesics and different administering regimens used in the clinic. This study aimed to compare the effectiveness and safety of two intravenous remifentanil dosage regimens in the first labor stage.

Patients and Methods

One hundred and fifteen parturients with a contraindication to epidural analgesia but were willing to receive systemic labor analgesia were randomized into group A received a fixed dose of remifentanil throughout the first stage of labor, and group B received an elevated dose of remifentanil during the active phase of the first stage both by patient-controlled analgesia (PCA). Maternal numerical rating scale (NRS) pain score and oxygen desaturation, sedation efficacy, satisfaction, as well as maternal and fetal adverse reactions were recorded and compared.

Results

The mean NRS pain scores before analgesia and in the latent phase showed no statistically significant difference between the two groups (P > 0.05). However, during the active phase, group B demonstrated significantly lower mean NRS pain scores and lowest pain score compared to group A (P < 0.05). Furthermore, group B exhibited higher overall sedation scores and satisfaction scores in comparison to group A (P < 0.05). The incidence of adverse reactions between the two groups was similar (P > 0.05).

Conclusion

Relatively elevated intravenous dosage of remifentanil with PCA during the active phase in the first stage of labor is safe and more effective than a fixed-dosage regimen for labor analgesia.

Trial Registration

This study was registered with ChiCTR on 24/08/2021 with trial identification number: ChiCTR2100050247. First participant was recruited on 31/08/2021. The last patient was recruited on 12/08/2022.

Side Effects of Intravenous Patient-Controlled Analgesia with Remifentanil Compared with Intermittent Epidural Bolus for Labour Analgesia - A Randomized Controlled Trial

INTRODUCTION

Epidural analgesia is considered a gold standard in obstetric anaesthesia and analgesia. However, in situation when it is contraindicated, unwanted by the patient or simply unavailable, remifentanil can be an excellent alternative. The goal of our study is to analyse the side effects of intravenous patient-controlled analgesia (IV PCA) with remifentanil compared with epidural analgesia during delivery.

MATERIAL AND METHODS

This study included 155 pregnant women in term for birth, divided into 2 groups: a remifentanil group (RG), and an epidural group (EG). Patients in the RG received intravenous PCA with remifentanil, while patients in the ЕG received epidural analgesia with programmed intermittent bolus dosing. Our primary outcome was maternal safety; the secondary outcome was neonatal safety.

RESULTS

The results present a significantly lower SaO2 value of the parturients in the RG (96.95 ± 1.4 vs 98.22 ± 0.6), and a significantly higher respiratory rate per minute in the EG at all time points after the onset of analgesia (20.85 ± 1.4 vs 18.67 ± 0.9). There was more frequent sedation, nausea and vomiting in the RG, while in the EG there was a more elevated temperature, itching and irregularities in the CTG record. Regarding the newborn, there was no significant difference between the two groups in the Apgar scores, pH, pCO2, pO2, and bicarbonate, while there was a significantly lower value of the base excess in the RG group.

CONCLUSION

PCA with remifentanil is safe for the mother, foetus and the newborn, with minimal side effects. Continuous respiratory monitoring, oxygen supply and following of all consensus recommendations are mandatory.

Patient-controlled Sedation Using Remifentanil for Third Molar Extraction

The purpose for this study was to examine the efficacy of patient-controlled sedation (PCS) with remifentanil as an intravenous adjunct to local anaesthesia for treating pain associated with dental extraction during monitored anaesthetic care. Forty ASA 1–2 and aged 18 or older Chinese patients presenting for third molar extraction on an outpatient basis were randomly assigned to either remifentanil (RG; n=20) or saline groups (CG; n=20). All patients completed the study. Patients in the RG and CG were comparable in terms of demographic variables, PCS demands and PCS boluses. There was high variability of PCS among patients in both groups in terms of demands (range for RG 0–62; CG 0–41) and consumption (range for RG 0–26; CG 0–13). Neither group required any rescue local anaesthetic injection for pain or midazolam for anxiety. There was no clinically relevant differences in outcome measures (pain scores, anxiety scores, systolic and diastolic blood pressures, heart rate, and SpO2) between the two groups. There were no other major complications such as apnoea, desaturation, bradycardia, or chest wall rigidity in either group. We conclude that, although it appeared to be safe, the addition of patient-controlled remifentanil was not a useful adjunct to local anaesthesia for pain associated with third molar dental extraction.

Continuous Epidural Analgesia Using an Ester-Linked Local Anesthetic Agent, 2-Chloroprocaine, During Labor: A Case Report

We report the use of the ester-linked local anesthetic, 2-chloroprocaine, for continuous epidural analgesia in a patient in labor with a history of allergic reaction to amide local anesthetics. The patient gave a reliable history of pruritus, hives, erythema, and swelling on her lower extremity after having received a preservative-free amide local anesthetic. This allergy had been confirmed by a dermatologist by her reports. The patient requested an epidural for labor analgesia that was placed successfully. After an initial bolus, a continuous infusion of 1.5% of 2-chloroprocaine was initiated to achieve satisfactory pain relief throughout an uneventful vaginal delivery.

A case series of vital signs-controlled, patient-assisted intravenous analgesia (VPIA) using remifentanil for labour and delivery

Intravenous remifentanil patient-controlled analgesia can be used during labour as an alternative to epidural analgesia. Adverse effects of opioids, including hypoxia and bradycardia, may lead to maternal morbidity and mortality. We devised an interactive feedback system based on a clinical proportional algorithm, to continuously monitor for adverse effects to enhance safety and better titrate analgesia. This vital signs-controlled, patient-assisted intravenous analgesia with remifentanil used a prototype delivery system linked to a pulse oximeter that evaluated maternal oxygen saturation and heart rate continuously. With this system, we detected oxygen saturation < 95% for more than 60 s in 15 of 29 subjects (52%); and heart rate < 60 min^-1 for more than 60 s in 7 of 29 subjects (24%) during use. The system automatically responded appropriately by reducing the dosages and temporarily halting remifentanil administration, thus averting further hypoxia and bradycardia.

Should Nitrous Oxide Be Used for Laboring Patients?

Nitrous oxide, long used during labor in Europe, is gaining popularity in the United States. It offers many beneficial attributes, with few drawbacks. Cost, safety, and side effect profiles are favorable. Analgesic effectiveness is highly variable, yet maternal satisfaction is often high among the women who choose to use it. Despite being less effective in treating labor pain than neuraxial analgesic modalities, nitrous oxide serves the needs and preferences of a subset of laboring parturients. Nitrous oxide should, therefore, be considered for inclusion in the repertoire of modalities used to alleviate pain and facilitate effective coping during labor.

The RESPITE trial: remifentanil intravenously administered patient-controlled analgesia (PCA) versus pethidine intramuscular injection for pain relief in labour: study protocol for a randomised controlled trial

BACKGROUND

The commonest opioid used for pain relief in labour is pethidine (meperidine); however, its effectiveness has long been challenged and the drug has known side effects including maternal sedation, nausea and potential transfer across the placenta to the foetus. Over a third of women receiving pethidine require an epidural due to inadequate pain relief. Epidural analgesia increases the risk of an instrumental vaginal delivery and its associated effects. Therefore, there is a clear need for a safe, effective, alternative analgesic to pethidine. Evidence suggests that remifentanil patient-controlled analgesia (PCA) reduces epidural conversion rates compared to pethidine; however, no trial has yet investigated this as a primary endpoint. We are, therefore, comparing pethidine intramuscular injection to remifentanil PCA in a randomised controlled trial.

METHODS/DESIGN

Women in established labour, requesting systemic opioid pain relief, will be randomised to either intravenously administered remifentanil PCA (intervention) or pethidine intramuscular injection (control) in an unblinded, 1:1 individual randomised trial. Following informed consent, 400 women in established labour, who request systemic opioid pain relief, from NHS Trusts across England will undergo a minimised randomisation by a computer or automated telephone system to either pethidine or remifentanil. In order to balance the groups this minimisation is based on four parameters; parity (nulliparous versus multiparous), maternal age (<20, 20 < 30, 30 < 40, 40+ years), ethnicity (South Asian (Pakistani/Indian/Bangladeshi) versus Other) and induced versus spontaneous labour. The effectiveness of pain relief provided by each technique will be recorded every 30 min after time zero, until epidural placement, delivery or transfer to theatre, quantified by Visual Analogue Scale. Incidence of maternal side effects including sedation, delivery mode, foetal distress requiring delivery, neonatal status at delivery and rate of initiation of breastfeeding within the first hour of birth will also be recorded. Maternal satisfaction with her childbirth experience will be determined by a postpartum questionnaire prior to discharge from the delivery ward.

DISCUSSION

The RESPITE trial's primary outcome is the proportion of women who have an epidural placed for pain relief in labour in each arm.

TRIAL REGISTRATION

Current Controlled Trials registration number: ISRCTN29654603 . Registered on 23 July 2013.

Intravenous remifentanil versus epidural ropivacaine with sufentanil for labour analgesia: a retrospective study

Remifentanil with appropriate pharmacological properties seems to be an ideal alternative to epidural analgesia during labour. A retrospective cohort study was undertaken to assess the efficacy and safety of remifentanil intravenous patient-controlled analgesia (IVPCA) compared with epidural analgesia. Medical records of 370 primiparas who received remifentanil IVPCA or epidural analgesia were reviewed. Pain and sedation scores, overall satisfaction, the extent of pain control, maternal side effects and neonatal outcome as primary observational indicators were collected. There was a significant decline of pain scores in both groups. Pain reduction was greater in the epidural group throughout the whole study period (0∼180 min) (P<0.0001), and pain scores in the remifentanil group showed an increasing trend one hour later. The remifentanil group had a lower SpO₂ (P<0.0001) and a higher sedation score (P<0.0001) within 30 min after treatment. The epidural group had a higher overall satisfaction score (3.8±0.4 vs. 3.7±0.6, P = 0.007) and pain relief score (2.9±0.3 vs. 2.8±0.4, P<0.0001) compared with the remifentanil group. There was no significant difference on side effects between the two groups, except that a higher rate of dizziness (1% vs. 21.8%, P<0.0001) was observed during remifentanil analgesia. And logistic regression analysis demonstrated that nausea, vomiting were associated with oxytocin usage and instrumental delivery, and dizziness was associated to the type and duration of analgesia. Neonatal outcomes such as Apgar scores and umbilical-cord blood gas analysis were within the normal range, but umbilical pH and base excess of neonatus in the remifentanil group were significantly lower. Remifentanil IVPCA provides poorer efficacy on labor analgesia than epidural analgesia, with more sedation on parturients and a trend of newborn acidosis. Despite these adverse effects, remifentanil IVPCA can still be an alternative option for labor analgesia under the condition of one-to-one bedside care, continuous monitoring, oxygen supply and preparation for neonatal resuscitation.

Coadministration of intravenous remifentanil and morphine for post-thoracotomy pain: comparison with intravenous morphine alone

OBJECTIVES

In this double-blind, randomized study, the authors compared the effects of a patient-controlled remifentanil and morphine combination with morphine alone on post-thoracotomy pain, analgesic consumption, and side effects.

DESIGN

A prospective, randomized, double-blind clinical study.

SETTING

University hospital.

PARTICIPANTS

Volunteer patients at a university hospital undergoing elective thoracotomy surgery.

INTERVENTIONS

Patients were allocated randomly into 2 groups to receive patient-controlled analgesia: the morphine (M) group or the morphine plus remifentanil (MR) group. Pain, discomfort, sedation scores, cumulative patient-controlled morphine consumption, rescue analgesic (meperidine) requirement and side effects were recorded for 24 hours.

MEASUREMENTS AND MAIN RESULTS

Sixty patients were allocated randomly to receive intravenous patient-controlled analgesia with morphine alone (M) or morphine plus remifentanil (MR) in a double-blind manner. Patients were allowed to use bolus doses of morphine (0.02 mg/kg) or the same dose of a morphine plus remifentanil (0.2 µg/kg) mixture every 10 minutes without a background infusion. VAS scores were lower in the MR group than in the M group at 30 minutes (p = 0.04), 1 hour (p = 0.03), and 2 hours (p = 0.04). Mean cumulative doses of morphine were not significantly different at 27.8±15 mg for the M group and 21.9±10.5 mg for the MR group. Significantly more patients needed meperidine in the M group (p = 0.039); these also experienced more nausea (p = 0.01).

CONCLUSIONS

Coadministration of PCA remifentanil with morphine for the treatment of post-thoracotomy pain did not reduce morphine consumption but provided superior analgesia, less use of rescue analgesics, and fewer side effects compared to morphine alone.

The Comparison of Patient-Controlled Remifentanil Administered by Two Different Protocols (Bolus and Bolus+Infusion) and Intramuscular Meperidine for Labor Analgesia

OBJECTIVE

Nowadays, there are many pain relief methods for reducing the pain and stress of labor and delivery. In our study, two different remifentanil protocols (bolus and bolus+infusion) administered by patient-controlled analgesia method were compared with intramuscular meperidine for labor analgesia.

METHODS

Ninety parturients who were scheduled for vaginal delivery were included in this study. Patients were randomly divided into 3 groups, with 15 primiparous and 15 multiparous patients in each group. Whenever a patient requested analgesics during the labor, Group M was given 1 mg kg(-1) intramuscular meperidine, Group B was given intravenous bolus patient-controlled remifentanil, and Group IB was given intravenous bolus+infusion patient-controlled remifentanil. Patients' systolic and diastolic blood pressure, heart rate, pain-comfort and sedation scores, remifentanil consumption, side effects, and Apgar scores of the newborns were evaluated during the labor and delivery.

RESULTS

Patients' mean pain and comfort scores were significantly lower in Groups B and IB than in Group M at all time intervals except the first minute. Compared with Group IB, mean pain and comfort scores at 15, 30, 60, and 120 minutes were significantly higher in Group B. The mean sedation scores were similar among the groups. Total remifentanil consumption was lower in Group IB than in Group B, but it was not statistically significant.

CONCLUSION

Patient-controlled intravenous bolus or bolus+infusion remifentanil provided more effective analgesia and patient comfort than intramuscular meperidine for labor analgesia. Especially during labor, bolus+infusion remifentanil administration provided better pain and patient comfort scores than bolus alone, without increasing remifentanil consumption.

Patient-Controlled Remifentanil Analgesia as Alternative for Pethidine with Midazolam During Oocyte Retrieval in IVF/ICSI Procedures: A Randomized Controlled Trial

BACKGROUND

Pethidine with midazolam-induced conscious sedation for pain relief during transvaginal oocyte retrieval for in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) procedures is associated with residual pain and oversedation. Patient-controlled analgesia (PCA) with remifentanil may serve as an alternative for pethidine. We investigated whether PCA remifentanil with diclofenac was associated with improved periprocedural pain relief than pethidine analgesia during IVF/ICSI procedures, with sedation scores, safety profiles, and patient satisfaction as secondary endpoints.

METHODS

Seventy-six women were randomized to receive pethidine (2 mg/kg i.m.) and midazolam (7.5 mg)-induced conscious sedation (n = 40) or PCA with remifentanil and diclofenac (50 mg; n = 36). The Numeric Rating Scale, McGill Pain Questionnaire (MPQ), Ramsey Sedation Scale, and a 5-day pain-and-discomfort diary were used to evaluate pain and sedation levels.

RESULTS

There were no differences in baseline characteristics and reproductive outcomes between both groups. Periprocedural pain scores were comparable for remifentanil and pethidine groups (4 [3 to 7] vs. 6 [4 to 8]; P = 0.13). Pain scores in the pethidine group were significantly lower at 30 minutes after the procedure (1 [0 to 3] vs. 2 [1 to 5]; P = 0.016), but at cost of higher sedation levels when compared to remifentanil (4 [2 to 4] vs. 2 [2 to 2]; P < 0.001). Patient satisfaction was higher, and MPQ scores were lower in the remifentanil group. There were no differences in safety profiles between both analgesics.

CONCLUSIONS

Patient-controlled analgesia with remifentanil showed a similar reduction in pain scores than pethidine with midazolam during oocyte retrieval, while pethidine induced the highest pain relief after the procedure. However, PCA remifentanil was associated with less sedation and a better patient satisfaction profile than pethidine.

Comparison of remifentanil: Entonox with Entonox alone in labor analgesia

Background:

We designed a study to evaluate the effectiveness of continuous low dose infusion of remifentanil adding to self-administration of entonox administered for pain relief during the active phase of first stage of labor.

Materials and Methods:

Thirty healthy term pregnant women recruited in our randomized double-blind, cross over study. They received the study medicines during two 30-min periods with a 15-min wash-out sequence after each period. Fifteen parturient used remifentanil as a single bolus dose followed by constant low dose infusion and self-administration of entonox (group R) during the first period and entonox and saline (group P) during the second period, while the remainder of the parturient used the drugs in a reverse order. Pain and Ramsay score, maternal and fetal hemodynamic, and ventilation were assessed during each intervention.

Results:

In this study, mean pain severity scores were 8 ± 0.9 before and 5.4 ± 1.7 after intervention in group P, and 7.8 ± 0.1, 3.5 ± 1.3 in group R, respectively. Mean pain severity difference was 2.6 ± 1.5 in group P, while 4.3 ± 1.5 in group R; so, use of entonox and remifentanil can decrease labor pain two times more in comparison with entonox/placebo (normal saline). However, hemodynamic and ventilation parameter in remifentanil/entonox period were same as in entonox/placebo period. No statistical differences were seen in mean Ramsay score between group R and P. There was no episode of maternal bradycardia, hypotension, or hypoxemia.

Conclusion:

Not only adding low dose infusion of remifentanil to self-administration of entonox was notable in labor pain reduction, it did n’t make more parturient and neonatal side-effects.

Remifentanil target-controlled infusion during second stage labour in high-risk parturients: a case series

BACKGROUND

Providing adequate analgesia and appropriate sedation to high-risk parturients during late second stage labour without compromising foetal safety remains a major challenge, especially in situations when neuraxial block is not applicable. Remifentanil emerged as an option for labour analgesia during the last decade but may be suitable for the facilitation of complicated vaginal deliveries as well.

METHODS

A retrospective chart review of nine labouring women with significant medical and/or obstetrical risk factors was conducted. According to the assessment of an experienced obstetrician, vaginal delivery could only be achieved with profound analgesia, and neuraxial block was not possible because of contraindications, technical failure, or shortage of time. Mode of delivery, need for neonatal resuscitation, maternal and neonatal vital parameters, drug consumption, and personnel resource expenses were recorded.

RESULTS

Remifentanil target-controlled infusion (TCI) facilitated vaginal delivery in eight out of nine women. No serious adverse events were observed, but three newborns needed initial respiratory support for a few minutes. The total cost of remifentanil TCI administration to facilitate vaginal delivery compared with the estimated additional cost of an emergency caesarean section was negligible.

CONCLUSION

This case series suggests that remifentanil TCI may be used to facilitate vaginal delivery in high-risk parturients when other forms of analgesia are limited. However, the small number of patients studied does not allow generalisation of the results; neither can safety concerns be dispelled yet.

Efficacy and safety of remifentanil as an alternative labor analgesic

The objective of this review was to evaluate the clinical efficacy and safety of remifentanil in the management of labor pain. Although neuraxial analgesia is the best option during labor, alternative analgesic options are needed for patients with contraindications. Using a systematic literature search, clinical outcomes of remifentanil for labor pain have been summarized. Also, comparisons of remifentanil to other options including meperidine, epidural analgesia, fentanyl, and nitrous oxide are provided. Based on the literature review, remifentanil is associated with high overall maternal satisfaction and favorable side-effect profile. However, due to the low reporting of adverse events, large, randomized controlled trials are needed to evaluate maternal and neonatal safety adequately and determine the optimal dosing needed to provide effective analgesia. While remifentanil is a feasible alternative for patients who cannot or do not want to receive epidural analgesia, administration should be monitored closely for potential adverse effects.

Two dosages of remifentanil for patient-controlled analgesia vs. meperidine during colonoscopy: a prospective randomized controlled trial

BACKGROUND AND STUDY: Combined use of opiates and benzodiazepines often results in delayed discharge after colonoscopy.

AIMS

To compare sedation quality of two dosages of patient controlled analgesia remifentanil with one another and with that of a midazolam-meperidine association during colonoscopy.

METHODS

Ninety patients undergoing colonoscopy were randomly assigned to three groups. Group M received a meperidine bolus (0.7 mg/kg) and sham patient controlled analgesia. Group R1 received remifentanil 0.5 μg/kg and group R2 remifentanil 0.8 μg/kg together with a patient-controlled analgesia pump injecting further boluses (2-min lock-out). Technical difficulties of the examination, gastroenterologist's and patient's satisfaction with sedoanalgesia were evaluated after colonoscopy on a 100 mm Visual Analogue Scale. Patient's satisfaction was assessed 24 h later.

RESULTS

Group M had more adverse events (p = 0.044), required more rescue boluses (p = 0.0010), had lower Observer's Assessment of Alertness and Sedation Scale score at the end of the procedure (p = 0.0016) and longer discharge time (p = 0.0001). Groups R1 and R2 did not differ with respect to these variables. Patient's degree of pain and satisfaction with sedo-analgesia, endoscopist's technical difficulty and satisfaction were not different among groups.

CONCLUSIONS

Remifentanil patient controlled analgesia is a safe approach to sedation for colonoscopy.

Efficacy and side effects of intravenous remifentanil patient-controlled analgesia used in a stepwise approach for labour: an observational study

BACKGROUND

Remifentanil has a suitable pharmacological profile for labour analgesia. In this prospective, observational study, intravenous patient-controlled analgesia with remifentanil, using stepwise bolus doses without background infusion, was examined during the first and second stages of labour. Outcomes were pain reduction, maternal satisfaction, maternal and neonatal side effects and remifentanil metabolism in the neonate.

METHODS

Parturients with normal term singleton pregnancies were recruited. The initial remifentanil bolus dose was 0.15 μg/kg, increasing in steps of 0.15 μg/kg, with a 2-min lock-out. Pain scores using a 100 mm visual analogue scale, systolic and diastolic blood pressures, respiratory rate and maternal sedation were recorded every 15 min. Maternal oxygen saturation and heart rate were monitored continuously. Neonatal data included Apgar scores, clinical examination, naloxone use, resuscitation, umbilical cord blood gases and remifentanil concentrations.

RESULTS

Forty-one parturients were enrolled. Pain scores were significantly reduced in the first 3 h of patient-controlled analgesia use compared to baseline, and at the end of the first and second stages of labour (P<0.05). Maximal pain reduction was 60% (P<0.01). One patient had inadequate pain relief and converted to epidural analgesia. The mean highest dose of remifentanil was 0.7 μg/kg [range 0.3-1.05]. Ninety-three percent of patients were satisfied with their analgesia. The lowest oxygen saturation was 91% and the lowest respiratory rate was 9 breaths/min. Eleven parturients (27%) received supplemental oxygen due to oxygen saturations <92%. Maternal sedation was moderate, and neonatal data reassuring.

CONCLUSIONS

Remifentanil intravenous patient-controlled analgesia provides adequate pain relief and high maternal satisfaction during the first and second stages of labour. Maternal sedation and respiratory depression may occur, but no serious neonatal side effects were recorded. Careful monitoring is mandatory.

Remifentanil patient controlled analgesia versus epidural analgesia in labour. A multicentre randomized controlled trial

BACKGROUND

Pain relief during labour is a topic of major interest in the Netherlands. Epidural analgesia is considered to be the most effective method of pain relief and recommended as first choice. However its uptake by pregnant women is limited compared to other western countries, partly as a result of non-availability due to logistic problems. Remifentanil, a synthetic opioid, is very suitable for patient controlled analgesia. Recent studies show that epidural analgesia is superior to remifentanil patient controlled analgesia in terms of pain intensity score; however there was no difference in satisfaction with pain relief between both treatments.

METHODS/DESIGN

The proposed study is a multicentre randomized controlled study that assesses the cost-effectiveness of remifentanil patient controlled analgesia compared to epidural analgesia. We hypothesize that remifentanil patient controlled analgesia is as effective in improving pain appreciation scores as epidural analgesia, with lower costs and easier achievement of 24 hours availability of pain relief for women in labour and efficient pain relief for those with a contraindication for epidural analgesia.Eligible women will be informed about the study and randomized before active labour has started. Women will be randomly allocated to a strategy based on epidural analgesia or on remifentanil patient controlled analgesia when they request pain relief during labour. Primary outcome is the pain appreciation score, i.e. satisfaction with pain relief.Secondary outcome parameters are costs, patient satisfaction, pain scores (pain-intensity), mode of delivery and maternal and neonatal side effects.The economic analysis will be performed from a short-term healthcare perspective. For both strategies the cost of perinatal care for mother and child, starting at the onset of labour and ending ten days after delivery, will be registered and compared.

DISCUSSION

This study, considering cost effectiveness of remifentanil as first choice analgesia versus epidural analgesia, could strongly improve the care for 180.000 women, giving birth in the Netherlands yearly by giving them access to pain relief during labour, 24 hours a day.

TRIAL REGISTRATION NUMBER

Dutch Trial Register NTR2551, http://www.trialregister.nl.