Programmed intermittent epidural bolus as compared to continuous epidural infusion for the maintenance of labor analgesia: a prospective randomized single-blinded controlled trial

An Innovative Approach to Determine Programmed Intermittent Epidural Bolus Pump Settings for Labor Analgesia: A Randomized Controlled Trial

BACKGROUND

Three settings are required on a programmed intermittent epidural bolus (PIEB) pump for labor analgesia: the PIEB next bolus (PIEBnb), PIEB interval (PIEBi), and PIEB volume (PIEBv). The ideal settings for these parameters are still unknown. We hypothesized a mathematical modeling tool, response surface methodology (RSM), could estimate 3 PIEB pump parameters while balancing 3 clinically important patient outcomes simultaneously. The study objective was to use RSM to estimate PIEB settings (PIEBnb, PIEBi, and PIEBv) while maximizing maternal satisfaction, minimizing the need for clinician-administered boluses, and optimizing the ratio of delivered/requested patient-controlled epidural analgesia (PCEA) boluses simultaneously.

METHODS

With institutional ethics approval, a double-blind randomized trial was completed in a tertiary care labor and delivery center. Nulliparous, English-speaking American Society of Anesthesiologists (ASA) physical status II patients aged 18 to 45 years at full term, single gestation in vertex presentation, in spontaneous labor and ≤7 cm cervical dilation were included. Patients with comorbidities, contraindications to neuraxial analgesia, using chronic analgesics, <152 cm, or body mass index (BMI) >45 kg/m2 were excluded. After informed consent, labor analgesia was initiated using 10 mL ropivacaine 0.2% with 10 µg/mL fentanyl solution and PCEA (volume 6 mL every 10 minutes). Patients were randomized to predetermined PIEB settings. RSM identified 3 pump settings that represented a stationary point that best maximized or minimized 3 outcomes simultaneously: PCEA ratio (a ratio closest to 1), clinician bolus (optimal is 0), and maternal satisfaction (visual analog scale, 0-100, ideal response is ≥90).

RESULTS

Of 287 potential participants, 192 did not meet inclusion criteria or declined to participate, and 26 were withdrawn, leaving 69 patients for study inclusion. Using RSM, the suggested PIEB settings for all the primary study outcomes were as follows: PIEBnb = 29.4 minutes, PIEBi = 59.8 minutes, and PIEBv = 6.2 mL. These PIEB settings corresponded to the following clinical outcomes: maternal satisfaction at 93.9%, PCEA ratio at 0.77, and need for clinician bolus at 0.29. The dermatome sensory score was between T10 and T5 in 89% of the patients. The median lowest Bromage score was 4.

CONCLUSIONS

This novel study used a mathematical model to estimate PIEB pump settings while simultaneously maximizing 3 clinical outcomes. Equally weighted clinical outcomes prevent maximal outcome optimization and may not reflect patient priorities. Future studies or quality improvement endeavors could use RSM methodology to estimate PIEB pump settings targeting optimal values for a single clinical outcome of determined importance to parturients.

Programmed Intermittent Epidural Bolus Reduces Workloads in Labor Analgesia: A Single Center's Experience

Background and Objectives: Labor epidural analgesia can be maintained through programmed intermittent epidural bolus (PIEB), continuous epidural infusion (CEI), or patient-controlled epidural analgesia (PCEA). Our department changed from CEI+PCEA to PIEB+PCEA as the maintenance method. The higher hourly dose setting in the current regimen brought to our concern that side effects would increase with proportional staff workloads. This study aimed to investigate the validity of our proposal that PIEB+PCEA may function as a feasible tool in reducing the amount of work in the obstetrics anesthesia units. Materials and methods: This 2-year retrospective review included parturients with vaginal deliveries under epidural analgesia. We compared the staff burden before and after the switch from CEI (6 mL/h, PCEA 6 mL lockout 15 min, group A) to PIEB (8 mL/h, PCEA 8 mL lockout 10 min, group B). The primary outcome was the difference of proportion of parturients requiring unscheduled visits between groups. Side effects and labor and neonatal outcomes were compared. Results: Of the 694 parturients analyzed, the proportion of those requiring unscheduled visits were significantly reduced in group B (20.8% vs. 27.7%, chi-square test, p = 0.033). The multivariate logistic regression showed that PIEB was associated with fewer unscheduled visits than CEI (OR = 0.53, 95% CI [0.36-0.80], p < 0.01). Group B exhibited a significantly lower incidence of asymmetric blockade, as well as motor blockade. In nulliparous subjects, obstetric anal sphincter injury occurred less frequently when PIEB+PCEA was used. Significantly more multiparous women experienced vacuum extraction delivery in group B than in group A, and they had a longer second stage of labor. Conclusions: The PIEB+PCEA protocol in our study reduced workloads in labor epidural analgesia as compared to CEI+PCEA, despite that a higher dose of analgesics was administered. Future studies are warranted to investigate the effect of manipulating the PIEB settings on the labor outcomes.

Influence of different volumes and frequency of programmed intermittent epidural bolus in labor on maternal and neonatal outcomes: A systematic review and network meta-analysis

STUDY OBJECTIVE

In labor, programmed intermittent epidural bolus (PIEB) can be defined as the bolus administration of epidural solution at scheduled time intervals. Compared to continuous epidural infusion (CEI) with or without patient controlled epidural analgesia (PCEA), PIEB has been associated with decreased pain scores and need for rescue analgesia and increased maternal satisfaction. The optimal volume and dosing interval of PIEB, however, has still not been determined.

DESIGN

Systematic review and network meta-analysis registered with PROSPERO (CRD42022362708).

SETTINGS

Labor.

PATIENTS

Pregnant patients.

INTERVENTIONS

Central, CINAHL, Global Health, Ovid Embase, Ovid Medline and Web of Science were searched for randomized controlled trials that examined pregnant patients in labor who received CEI or PIEB with or without a PCEA component. Network meta-analysis was performed with a frequentist method, facilitating the indirect comparison of PIEB with different volumes and dosing intervals through the common comparator of CEI and substituting or supplementing direct comparisons with these indirect ones. Continuous and dichotomous outcomes were presented as mean differences and odds ratios, respectively, with 95% confidence intervals. The risk of bias was evaluated using the Cochrane risk of bias 2 tool.

MAIN RESULTS

Overall, 30 trials were included. For the first primary endpoint, need for rescue analgesia, PIEB delivered at a volume of 4 ml and frequency of 45 min (4/45) was inferior to PIEB 8/45 (OR 3.55; 95% CI 1.12-11.33), PIEB 10/60 was superior to PIEB 2.5/15 (OR 0.36; 95% CI 0.16-0.82), PIEB 4/45 (OR 0.14; 95% CI 0.03-0.71) and PIEB 5/60 (OR 0.23; 95% CI 0.08-0.70), and PIEB 5/30 was not inferior to PIEB 10/60 (OR 0.61; 95% CI 0.31-1.19). For the second primary endpoint, maternal satisfaction, no differences were present between the various PIEB regimens. The quality of evidence for these multiple primary endpoints was low owing to the presence of serious limitations and imprecision. Importantly, PIEB 5/30 decreased the pain score at 4 h compared to PIEB 2.5/15 (MD 2.45; 95% CI 0.13-4.76), PIEB 5/60 (MD -2.28; 95% CI -4.18--0.38) and PIEB 10/60 (MD 1.73; 95% CI 0.31-3.16). Mean ranking of interventions demonstrated PIEB 10/60 followed by PIEB 5/30 to be best placed to reduce the cumulative dose of local anesthetic, and this resulted in an improved incidence of lower limb motor blockade for PIEB 10/60 in comparison to CEI (OR 0.30; 95% CI 0.14-0.67). No differences in neonatal outcomes were found. Some concerns were present for the risk of bias in two thirds of trials and the risk of bias was shown to be high in the remaining one third of trials.

CONCLUSIONS

Future research should focus on PIEB 5/30 and PIEB 10/60 and how the method of analgesia initiation, nature and concentration of local anesthetic, design of epidural catheter and rate of administration might influence outcomes related to the mother and neonate.

Programmed intermittent epidural bolus as an ideal method for labor analgesia: a randomized controlled trial

BACKGROUND

Although programmed intermittent epidural bolus (PIEB) is effective for labor analgesia, an appropriate flow rate has not been established. Therefore, we investigated the analgesic effect based on different epidural injection flow rates.

METHODS

Nulliparous women scheduled for spontaneous labor were enrolled in this randomized trial. After injection of intrathecal 0.2% ropivacaine 3 mg with fentanyl 20 μg, participants were randomized to three study groups. Epidural analgesics, 10 ml during one hour, were administered with patient controlled epidural analgesia as follows (0.2% ropivacaine 60 ml, fentanyl 180 μg, and 0.9% saline 40 ml): continuous (n = 28, 10 ml/h for continuous infusion), PIEB (n = 29, 240 ml/h for bolus infusion of 10 ml), or manual (n = 28, 1200 ml/h for bolus injection of 10 ml). The primary outcome was hourly consumption of the epidural solution. The time interval between labor analgesia and the first breakthrough pain was investigated.

RESULTS

The median (Q1, Q3) hourly consumption of epidural anesthetics was significantly different among the groups (continuous: 14.3 [8.7, 16.9] ml, PIEB: 9.4 [6.2, 9.8] ml, manual: 8.6 [7.6, 9.9] ml; P < 0.001). The time to breakthrough pain for the PIEB group was longer than that for the other groups (continuous: 78.5 [35.8, 185.0] min, PIEB: 200.0 [88.5, 441.5] min, manual: 60.5 [37.3, 162.0] min, P = 0.027).

CONCLUSIONS

PIEB, with a low-flow rate, provided more adequate labor analgesia than a continuous epidural infusion or manual injection with a high-flow rate.

Tools for assessing labour pain: a comprehensive review of research literature

ABSTRACT

The experience of pain associated with labour is complex and challenging to assess. A range of pain measurement tools are reported in the literature. This review aimed to identify current tools used in research to assess labour pain across the past decade and to evaluate their implementation and adequacy when used in the context of labour pain. A literature search was conducted in databases MEDLINE and Cumulative Index of Nursing and Allied Health Literature, using search terms relating to labour, pain, and measurement. A total of 363 articles were selected for inclusion. Most studies (89.9%) assessed pain as a unidimensional experience, with the most common tool being the Visual Analogue Scale, followed by the Numerical Rating Scale. Where studies assessed pain as a multidimensional experience, the most common measurement tool was the McGill Pain Questionnaire. Only 4 studies that used multidimensional tools selected a tool that was capable of capturing positive affective states. Numerous variations in the implementation of scales were noted. This included 35 variations found in the wording of the upper and lower anchors of the Visual Analogue Scale, some assessment tools not allowing an option for "no pain," and instances where only sections of validated tools were used. It is clear that development of a standardised pain assessment strategy, which evaluates the multidimensions of labour pain efficiently and effectively and allows for both positive and negative experiences of pain to be reported, is needed.

Application of dural puncture epidural technique combined with programmed intermittent epidural bolus mode in labor analgesia: A randomized clinical trial

BACKGROUND

This study aims to evaluate the onset, maintenance, side effects s and the effect on newborns of dural puncture epidural (DPE) technique combined with programmed intermittent epidural bolus (PIEB) mode for labor analgesia as compared to conventional epidural (EP) technique combined with continuous epidural infusion (CEI) mode.

METHODS

All patients were randomly assigned to receive EP + CEI (Group EC), EP + PIEB (Group EP), DPE + CEI (Group DC) and DPE + PIEB (Group DP). Record the time to reach Numerical Rating Scale (NRS) ≤ 1, ropivacaine consumption, the NRS when the uterine neck whole opened (NRS2), the incidence of bilateral sensory block level to S2, asymmetric block, incomplete analgesia, replacement of catheter, intrapartum fever, as well as the occurrence of neonatal Apgar score ≤ 7 at 1 minute and 5 minutes.

RESULTS

A total of 455 women were included (111 in Group EC, 116 in Group EP, 114 in Group DC and 114 in Group DP). The time to reach NRS ≤ 1 in Group DP and Group DC was shorter than that in Group EP and Group EC (P < .05); the consumption of ropivacaine in Group DP was less than that in 3 other groups (P < .05); the incidence of incomplete analgesia and intrapartum fever in Group DP was lower than that in other 3 groups (P < .05).

CONCLUSIONS

DPE technique can provide faster analgesia than conventional EP technique, combined with PIEB mode maybe superior to traditional methods as a labor analgesia regimen.

Automated mandatory bolus versus basal infusion for maintenance of epidural analgesia in labour

BACKGROUND

Epidural analgesia is often used for pain relief during labour and childbirth, and involves administration of local anaesthetics (LA) into the epidural space resulting in sensory blockade of the abdomen, pelvis, and perineum. Epidural opioids are often co-administered to improve analgesia. Administration of epidural medications can be accomplished by basal infusion (BI) or automated mandatory bolus (AMB). With BI, medications are administered continuously, while AMB involves injecting medications at set time intervals. Patient-controlled epidural analgesia (PCEA) on top of AMB or BI enables patients to initiate additional boluses of epidural medications.  The superior method of delivering epidural medications would result in lower incidence of pain requiring anaesthesiologist intervention (breakthrough pain). Also, it should be associated with lower incidence of epidural-related adverse effects including caesarean delivery, instrumental delivery (use of forceps or vacuum devices), prolonged duration of labour analgesia, and LA consumption. However, clear evidence of the superiority of one technique over the other is lacking. Also, differences in the initiation of epidural analgesia such as combined spinal-epidural (CSE) (medications given into the intrathecal space in addition to the epidural space) compared to epidural only, and medications used (types and doses of LA or opioids) may not have been accounted for in previous reviews.  Our prior systematic review suggested that AMB reduces the incidence of breakthrough pain compared to BI with no significant difference in the incidence of caesarean delivery or instrumental delivery, duration of labour analgesia, and LA consumption. However, several studies comparing AMB and BI have been performed since then, and inclusion of their data may improve the precision of our effect estimates.

OBJECTIVES

To assess the benefits and harms of AMB versus BI for maintaining labour epidural analgesia in women at term.

SEARCH METHODS

We searched CENTRAL, Wiley Cochrane Library), MEDLINE, (National Library of Medicine), Embase(Elseiver), Web of Science (Clarivate), the WHO-ICTRP (World Health Organization) and ClinicalTrials.gov (National Library of Medicine) on 31 December 2022. Additionally, we screened the reference lists of relevant trials and reviews for eligible citations, and we contacted authors of included studies to identify unpublished research and ongoing trials.

SELECTION CRITERIA

We included all randomised controlled studies that compared bolus dosing AMB with continuous BI during epidural analgesia. We excluded studies of women in preterm labour, with multiple pregnancies, with fetal malposition, intrathecal catheters, those that did not use automated delivery of medications, and those where AMB and BI were combined.

DATA COLLECTION AND ANALYSIS

We used standard methodology for systematic review and meta-analysis described by Cochrane. Primary outcomes included: incidence of breakthrough pain requiring anaesthesiologist intervention; incidence of caesarean delivery; and incidence of instrumental delivery. Secondly, we assessed the duration of labour; hourly LA consumption in bupivacaine equivalents, maternal satisfaction after fetal delivery, and neonatal Apgar scores.  The following subgroup analyses were chosen a priori: epidural alone versus CSE technique; regimens that used PCEA versus those that did not; and nulliparous versus combination of nulli- and multi-parous women. We used the GRADE system to assess the certainty of evidence associated with our outcome measures.

MAIN RESULTS

We included 18 studies of 4590 women, of which 13 enrolled healthy nulliparous women and five included healthy nulli- and multiparous women. All studies excluded women with preterm or complicated pregnancies. Techniques used to initiate epidural analgesia differed between the studies: seven used combined spinal epidural, 10 used epidural, and one used dural puncture epidural (DPE). There was also variation in analgesics used. Eight studies utilised ropivacaine with fentanyl, three used ropivacaine with sufentanil, two utilised levobupivacaine with sufentanil, one used levobupivacaine with fentanyl, and four utilised bupivacaine with fentanyl. Most of the studies were assessed to have low risk of randomisation, blinding, attrition, and reporting biases, except for allocation concealment where eight studies were assessed to have uncertain risk and three with high risk. Our results showed that AMB was associated with lower incidence of breakthrough pain compared to BI (risk ratio (RR) 0.71; 95% confidence interval (CI) 0.55 to 0.91; I2 = 57%) (16 studies, 1528 participants), and lower hourly LA consumption in bupivacaine equivalents (mean difference (MD) -0.84 mg/h; 95% CI -1.29 to -0.38, I2 = 87%) (16 studies, 1642 participants), both with moderate certainty. AMB was associated with an estimated reduction in breakthrough pain incidence of 29.1% (incidence 202 per 1000, 95% CI 157 to 259), and was therefore considered clinically significant. The incidence of caesarean delivery (RR 0.85; 95% CI 0.69 to 1.06; I2 = 0%) (16 studies, 1735 participants) and instrumental delivery (RR 0.85; 95% CI 0.71 to 1.01; I2 = 0%) (17 studies, 4550 participants) were not significantly, both with moderate certainty. There was no significant difference in duration of labour analgesia (MD -8.81 min; 95% CI -19.38 to 1.77; I2 = 50%) (17 studies, 4544 participants) with moderate certainty. Due to differences in the methods and timing of outcome measurements, we did not pool data for maternal satisfaction and Apgar scores. Results reported narratively suggest AMB may be associated with increased maternal satisfaction (eight studies reported increased satisfaction and six reported no difference), and all studies showed no difference in Apgar scores. WIth the exception of epidural alone versus CSE which found significant subgroup differences in LA consumption between AMB and BI, no significant differences were detected in the remaining subgroup analyses.

AUTHORS' CONCLUSIONS

Overall, AMB is associated with lower incidence of breakthrough pain, reduced LA consumption, and may improve maternal satisfaction. There were no significant differences between AMB and BI in the incidence of caesarean delivery, instrumental delivery, duration of labour analgesia, and Apgar scores. Larger studies assessing the incidence of caesarean and instrumental delivery are required.

Combined Programmed Intermittent Bolus and Patient-Controlled Bolus Is a More Favorable Setting for Epidural Pain Relief Than Continuous Infusion

Epidural analgesia is a suitable and effective treatment for labor pain. However, the preferable modality setting for delivery remains debatable. This study adopted a programmed intermittent epidural bolus (PIEB) setting in conjunction with a patient-controlled epidural analgesia (PCEA) setting to improve the quality of labor analgesia and reduce the number of medical staff. We conducted a prospective observational analysis of primigravida parturients scheduled for spontaneous labor, which required epidural analgesia for painless labor. A total of 483 healthy primigravida parturients with singleton pregnancies were included in this cohort; 135 nulliparous patients were assigned to the continuous infusion setting (CEI) group and 348 to the PIEB + PCEA group. Compared to the CEI setting, the PIEB + PCEA setting significantly reduced the manual rescue by the clinician, extended the time required for the first manual rescue dose, and acclaimed good maternal satisfaction. The use of the CEI mode increased for poor performance requiring more than two rescues with an odds ratio of 2.635 by a binary logistic regression analysis. Using the PIEB + PCEA setting as the maintenance infusion had a longer duration for the first requested manual rescue, fewer manual rescue boluses, excellent satisfaction, and no significant increase in adverse events compared to the CEI setting.

Comparison of different delivery modalities of epidural analgesia and intravenous analgesia in labour: a systematic review and network meta-analysis

PURPOSE

In labour, neuraxial analgesia is the standard in the provision of pain relief. However, the optimal mode of delivering epidural solution has not been determined, and some parturients may need an alternative to epidural analgesia. We sought to conduct a systematic review and network meta-analysis to compare continuous epidural infusion (CEI), programmed intermittent epidural bolus (PIEB), computer-integrated CEI, computer-integrated PIEB, patient-controlled epidural bolus (PCEA), fentanyl patient-controlled analgesia (PCA), and remifentanil PCA, either alone or in combination.

METHODS

We searched CENTRAL, CINAHL, Ovid Embase, Ovid Medline, and Web of Science for randomized controlled trials that included nulliparous and/or multiparous parturients in spontaneous or induced labour. The maintenance epidural solution had to include a low concentration local anesthetic and an opioid. Specific subgroups in the obstetric population such as preeclampsia were excluded. Network meta-analysis was performed with a frequentist method, and continuous and dichotomous outcomes are presented as mean differences and odds ratios, respectively, with 95% confidence intervals.

RESULTS

Overall, 73 trials were included. For the first coprimary outcome, the need for rescue analgesia, CEI was inferior to PIEB and PIEB + PCEA was superior to PCEA alone, with a low certainty of evidence given the presence of serious limitations and imprecision. The second coprimary outcome, the maternal satisfaction, was improved by PIEB + PCEA compared with CEI + PCEA and PCEA alone, with a low quality of evidence in view of the presence of serious limitations and imprecision. Fentanyl PCA increased the requirement for rescue analgesia and decreased maternal satisfaction relative to many methods of delivering epidural solution. In terms of secondary outcomes, PIEB increased analgesic efficacy compared with CEI, and PCEA reduced local anesthetic consumption at the expense of inferior analgesia relative to CEI and PIEB. PIEB + PCEA was superior to CEI + PCEA in regard to the pain score at 2 h and 4 h, consumption of local anesthetic, incidence of lower lower limb motor blockade and the rate of spontaneous vaginal delivery. Fentanyl and remifentanil PCA did not provide the same level of analgesia as all epidural methods, resulted in increasing analgesic ineffectiveness with time spent in labour, and predisposed to a higher incidence of side effects such as nausea and/or vomiting and sedation. Remifentanil PCA was superior to fentanyl PCA for analgesia at an early time point, and it increased the incidence of oxygen desaturation relative to other strategies of delivering epidural solution.

CONCLUSIONS

Opioid PCA did not provide the same level of analgesia as epidural methods with a higher incidence of side effects. We interpret the findings of our systematic review and network meta-analysis as suggesting PIEB + PCEA to be the optimal delivery mode of epidural solution. Nevertheless, the potential differing importance of the various maternal, fetal, and neonatal outcomes in determining which is optimal has not, to our knowledge, been elucidated yet.

STUDY REGISTRATION

PROSPERO (CRD42021254978); registered 27 May 2021.

Effect of adding dexmedetomidine on two methods of labor analgesia via epidural among parturient patients

Background

Continuous epidural infusion (CEI) has been an optimal and acceptable technique for inducing epidural anesthesia. This study compared two methods of programmed intermittent epidural bolus (PIEB) with CEI in labor analgesia among patients receiving epidural dexmedetomidine.

Methods

This study was a randomized clinical trial. The target population was term women candidates for epidural anesthesia. After selection of sample size based on inclusion criteria, a total of 3 cc of dexmedetomidine (0.5 µg/ml) and Ropivacaine 0.1% was injected. Furthermore, 5 ml was injected as a loading dose of dexmedetomidine 0.5 µg /ml and Ropivacaine 0.1%. Then the pain score was recorded. SPSS software Version 23 was used for statistical analysis of data.

Results

The neonatal Apgar score in PIEB method was more improved (P = 0.003) and the use of assisted delivery tools such as vacuum, in PIEB method was reduced. (p=0.038) Duration of the first phase of the labor in this method was more reduced than CEI.(p=0.015) Patients in the group undergoing epidural anesthesia by PIEB method were associated with a higher level of satisfaction with the delivery process (p < 0.05) than patients undergoing CEI protocol.

Conclusion

PIEB method is associated with further improvement in neonatal Apgar score and maternal outcomes (reduction in the duration of the first phase of labor and no need to use assisted delivery methods) compared to the CEI protocol, but has little effect on hemodynamic conditions or drug dosage.

Comparison of programmed intermittent epidural bolus injection and continuous epidural injection in controlling nighttime pain and improving sleep quality after thoracotomy

BACKGROUND

Postoperative pain after open thoracotomy is known to be very severe and affects sleep quality. This study aimed to investigate the effects of a programmed intermittent epidural bolus injection versus continuous epidural injection for controlling nighttime pain and improving sleep quality after thoracotomy.

METHODS

Seventy-six patients scheduled for open thoracotomy for lung cancer or other lung diseases were enrolled. The participants were divided into 2 groups. Group A was continuously injected with 0.2% levobupivacaine at 1.1 mL/h, and group B was injected intermittently with 3 mL 0.2% levobupivacaine at 3 hours intervals through a thoracic epidural catheter via a programmed infusion pump. Within 48 hours after surgery, the degree of pain control using visual analog scale and the patients' sleep conditions on postoperative day (POD) 0 and 1 were evaluated, and other adverse events were investigated.

RESULTS

On POD 1 night, the visual analog scale in group B showed lower than group A (P = .009). Comparison of time to fall asleep showed no differences between 2 groups. Total sleep time was no difference on POD 0 but was longer in group B than that in group A on POD 1 (P = .042). Awakening from sleep on POD 0 was lower in group B than that in group A (P = .033), and satisfaction with sleep quality on POD 0 was superior in group B compared to group A (P = .005). Postoperative nausea and vomiting occurred more frequently in group B than in group A (P = .018).

CONCLUSION

The programmed intermittent epidural bolus technique of patient-controlled epidural analgesia reduces postoperative nighttime pain and improves sleep quality in patients undergoing thoracotomy for lung cancer or other lung diseases.

Analgesic Effects, Birth Process, and Prognosis of Pregnant Women in Normal Labor by Epidural Analgesia Using Sufentanil in Combination with Ropivacaine: A Retrospective Cohort Study

Objective. The objective is to evaluate the analgesic, labor, and prognostic effects of patient-controlled epidural analgesia (PCEA) versus sufentanil in conjunction with ropivacaine in normal labor. Methods. Sixty pregnant women who had a normal delivery at our hospital between February 2019 and April 2021 were included. Pregnant women were arbitrarily assigned to a control group and a research group. Pregnant women in the control group received lidocaine analgesia and PCEA with sufentanil combined with ropivacaine in the research group. Satisfaction with care, fetal umbilical artery blood flow, VAS score, labor and bleeding, neonatal Apgar score and incidence of adverse events were analyzed. Results. First, we made a comparison of satisfactory performance of nursing care. The satisfaction rate of the research group was 100.00%, compared to 83.33% for the control group. Nursing satisfaction was higher in the research group, and the difference was statistically significant ( $P<0.05$ ). Following analgesia, PI, RI, and S/D values of umbilical artery blood flow were lower in the research group than those in the control group, but the difference was not statistically significant ( $P>0.05$ ). The VAS scores at 10 min, 20 min, and 30 min were found to be lower in the research group than in the control group after analgesia, and the difference was statistically significant ( $P<0.05$ ). Bleeding was significantly lower in the research group for all stages of labor, and the difference was statistically significant ( $P<0.05$ ). Apgar scores at 1 minute, 5 minutes, and 10 minutes postpartum were greater in the research group than in the control group, and the difference was statistically significant ( $P<0.05$ ). As a final note, the incidence of pruritus, hypotension, respiratory depression, nausea, and vomiting was found to be lower in the research group than in the control group, and the difference was statistically significant ( $P<0.05$ ). Conclusion. PCEA with sufentanil coupled with ropivacaine was used to perform labor analgesia. With significant reduction in maternal pain and assurance of labor, ropivacaine combined with sufentanil epidural labor analgesia did not reduce fetal umbilical artery blood flow without extended labor. It could not affect the labor process or the safety of the fetus, which is safe for the mother and fetus.

Comparison of Continuous Infusion of Ropivacaine and Fentanyl With Intermittent Bolus Doses of Ropivacaine and Fentanyl for Epidural Labor Analgesia: A Randomized Open-Label Study

Background

The purpose of this study was to compare the efficacy of continuous epidural infusion with intermittent bolus doses for labour analgesia using ropivacaine 0.2% and opioids.

Methods

In this study, 70 primigravida patients were randomly divided into two groups of 35 each. Both groups received a loading dose of 10ml of 0.2% ropivacaine and 1μg/ml fentanyl in 5ml incremental doses while monitoring blood pressure and heart rate. Subsequently, Group I received a continuous epidural infusion of 0.2% ropivacaine with fentanyl at 10ml/hr, while Group II received 10 ml of 0.2% ropivacaine with fentanyl in bolus form every hour manually, with the first dose given after one hour of the initial loading dose. A rescue bolus dose of 5ml of 0.2% ropivacaine was given in both groups when they complained of breakthrough pain (VAS score >3). An additional 5ml bolus dose was given in both groups at the time of crowning. The blood pressure, heart rate, and severity of pain using the visual analogue scale (VAS) were assessed. Total drug volume utilized, the number of bolus doses, duration of the first and second stage of labour, rate of instrumental delivery and cesarean section, and neonatal Apgar scores were also recorded.

Results

The total volume of drugs consumed and the number of boluses required for breakthrough pain were both significantly lower in Group II. There was a similar decrease in hemodynamic parameters (systolic blood pressure, diastolic blood pressure, and mean arterial pressure) from baseline in both the groups with no significant difference between them. The onset of analgesia was significantly faster in Group I with both groups achieving optimum analgesia (VAS ≤ 3) within 20 minutes of the loading dose. Maternal motor blockade scores, the duration of the first and second stage of labour, the rate of instrumental delivery, cesarean section, and neonatal Apgar scores, did not show any statistically significant difference between the two groups.

Conclusion

Both techniques, i.e. continuous epidural infusion and intermittent epidural boluses are effective for providing labour analgesia. But consumption of drugs and episodes of breakthrough pain was higher in the continuous infusion group (Group I).

Optimization of programmed intermittent epidural bolus volume for different concentrations of ropivacaine in labor analgesia: a biased coin up-and-down sequential allocation trial

Background and objectives

To date, programmed intermittent epidural bolus (PIEB) has been widely used in obstetric analgesia, while no optimal PIEB regimen has been proposed. This study aimed to assess effective analgesia in 90% of women (EV90) with different concentrations of ropivacaine (0.075% and 0.1%) combined with 0.5 µg/mL sufentanil, at an interval of 40 min using the biased coin design-up-and-down method (BCD-UDM), and to explore whether there is a difference in EV90 with the increase of ropivacaine concentration.

Methods

In total, 103 primiparous women were assigned to two groups, including group A (n = 52) and group B (n = 51). Parturients in group A were treated with 0.075% ropivacaine and 0.5 µg/mL sufentanil, while those in group B were treated with 0.1% ropivacaine and 0.5 µg/mL sufentanil. Used the biased coin up-and-down sequential allocation method to determine the EV90. The secondary outcomes were sensory block level, motor block, and adverse events (hypotension, urinary retention, and pruritus).

Results

The results revealed that EV90 was 10 mL (95% confidence interval (CI):8.03–11.54) in group A, and EV90 was 9 mL (95% CI:7.49–10.51) in group B by the isotonic regression method. The highest level of the sensory block was T8, and the lowest was T12. No case of hypotension was recorded,and only 4 parturients complained of motor block.

Conclusion

With an interval of 40 min, the optimal PIEB bolus volume of 0.075% ropivacaine and 0.5 µg/mL sufentanil was 10 mL, 0.1% ropivacaine and 0.5 µg/mL sufentanil was 9 mL. Moreover, the PIEB volume decreased along with the higher concentration of ropivacaine.

Trial registration

ChiCTR registration number: ChiCTR2000040917. Registration date: December 15, 2020.

Programmed intermittent epidural bolus in parturients: A meta-analysis of randomized controlled trials

BACKGROUND

To evaluate the efficacy and safety of programmed intermittent epidural bolus (PIEB) in parturients.

METHODS

The PubMed, Embase, and the Cochrane Library (from inception to July 2021) were searched for identification of randomized placebo-controlled trials in which PIEB was applied in parturients. The outcomes were the effect of analgesia, satisfaction score, mode of delivery, duration of labor, neonatal condition, and adverse events. The pooled odds ratios (OR), weighted mean difference (WMD), and 95% confidence intervals (CIs) were calculated using random- and fixed-effects models.

RESULTS

PIEB was found to be associated with decreased total consumption of ropivacaine (WMD = -15.83, 95% CI: -19.06 to -12.60, P < .00001; I2 = 61%; P for heterogeneity = .04), total consumption of sufentanil (WMD = -4.93, 95% CI: -6.87 to 2.98, P < .00001; I2 = 68%; P for heterogeneity = .05), numbers of patients who require patient-controlled epidural analgesia bolus (OR = 0.27, 95% CI: 0.14-0.51, P < .0001; I2 = 65%; P for heterogeneity = .01), the number of attempts (WMD = -4.12, 95% CI: -7.21 to -1.04, P = .009; I2 = 100%; P for heterogeneity < .00001), rate of breakthrough pain (OR = 0.47, 95% CI: 0.28-0.80, P = .005; I2 = 47%; P for heterogeneity = .09). Eight studies focus on the duration of analgesia. After by meta-analysis, we found that the pain visual analogue scale (VAS) score at 30 minutes, 2 hours, 4 hours, and 5 hours in PIEB group was significantly lower when compared with control group, (WMD = -0.15, 95% CI: -0.26 to -0.04, P = .006; I2 = 0%; P for heterogeneity = .64), (WMD = -0.79, 95% CI: -1.32 to 0.25, P = .004; I2 = 97%; P for heterogeneity < .00001), (WMD = -1.00, 95% CI: -1.08 to -0.91, P < .00001; I2 = 0%; P for heterogeneity = .67), (WMD = -1.81, 95% CI: -3.23 to -0.39, P = .01; I2 = 98%; P for heterogeneity < .00001), respectively. Nineteen studies discussed the mode of delivery between 2 groups. The results suggest that the rate of normal delivery is significantly higher in PIEB group compared with control group (OR = 1.37, 95% CI: 1.08-1.75, P = .01). The time of first and second stage of labor are significantly shorter in PIEB group compared with control group, the result is (WMD = -10.52, 95% CI: -14.74 to 4.76, P < .00001; I2 = 0%; P for heterogeneity = .86), (WMD = -1.48, 95% CI: -2.26 to -0.69, P = .0002; I2 = 35%; P for heterogeneity = .10), respectively. Thirteen studies concerned the satisfaction score of patients. The satisfaction score of patients in the PIEB group was significantly higher when compared with control group (WMD = 0.91, 95% CI: 0.42-1.39, P = .0003; I2 = 98%; P for heterogeneity < .00001). The Apgar score at 1, 5 minutes in PIEB group are significantly higher (WMD = 0.07, 95% CI: 0.02-0.13 P = .007; I2 = 55%; P for heterogeneity = .04), (WMD = -0.08, 95% CI: -0.12 to -0.05, P < .00001; I2 = 21%; P for heterogeneity = .27), respectively.

CONCLUSIONS

PIEB is a good alternative for labor analgesia with better analgesic effect, maternal and infant outcome.

Programmed intermittent epidural bolus for labour analgesia: a randomized controlled trial comparing bolus delivery speeds of 125 mL·hr-1 versus 250 mL·hr-1

PURPOSE

Programmed intermittent epidural bolus (PIEB) provides better analgesia for labour pain than continuous epidural infusion does. Nevertheless, commonly used PIEB regimens are associated with high sensory block. We hypothesized that a PIEB technique with slower bolus delivery speed would produce lower sensory levels.

METHODS

We recruited term nulliparous women with singleton pregnancies during the first stage of labour. All participants had an American Society of Anesthesiologists Physical Status score of II-III, had epidural catheters placed at L3/4, and had epidural analgesia maintained with PIEB 10 mL every 40 min using 0.0625% bupivacaine with fentanyl 2 µg·mL^-1. Women were randomized to receive PIEB delivered at 250 mL·hr^-1 (G250) or 125 mL·hr^-1 (G125). The study was completed six hours after the loading dose or at full cervical dilatation, whichever occurred first. The primary outcome was the presence of sensory block to ice ≥ T6 in at least one assessment during the study period (maximum six hours).

RESULTS

We analyzed data from 90 women. The proportion of women presenting sensory block ≥ T6 at any time was not different between G125 and G250 groups (60.0% vs 64.4%; difference, -4.4%; 95% confidence interval [CI], -24.5 to 15.6; P = 0.66). The median [interquartile range] highest sensory block level was also not different between G125 and G250 groups (T6 [T7-T5] vs T5 [T7-T5], P = 0.39). Women in the G125 group had a lower incidence of hypotension than women in the G250 group did (11.1% vs 33.3%; difference, -22.2%; 95% CI, -38.8 to -5.67; P = 0.01). Quality of analgesia and patient satisfaction were not different between groups.

CONCLUSION

The maintenance of epidural analgesia with a PIEB delivery speed of 125 mL·hr^-1 did not produce lower sensory block levels when compared with 250 mL·hr^-1. The slower injection speed regimen was associated with lower incidence of hypotension, but this secondary finding warrants confirmation in a future trial.

TRIAL REGISTRATION

www.ClinicalTrials.gov (NCT03236298); registered 1 August 2017.

Comparative analgesic efficacy and safety of intermittent local anaesthetic epidural bolus for labour: a systematic review and meta-analysis

BACKGROUND

Continuous epidural infusion (CEI) is commonly used for labour analgesia, but concerns over potential motor block, second-stage labour complications, and ineffective analgesia in late labour have prompted examining intermittent epidural bolus (IEB) as an alternative. However, evidence comparing these modalities is conflicting. The meta-analysis evaluates the analgesic efficacy of CEI vs IEB.

METHODS

Databases were searched for trials comparing CEI to IEB for labour analgesia. The two co-primary outcomes were risk of breakthrough pain and difference in area under the curve (AUC) for pain scores during the first 4 h post-epidural initiation. Local anaesthetic consumption, maternal outcomes (i.e. delivery mode, labour duration, and maternal satisfaction), and side-effects of epidural analgesia were also evaluated. Results were pooled using random-effects modelling. Trial sequential analysis (TSA) was used to evaluate evidence reliability.

RESULTS

Twenty-seven studies (3133 patients) were analysed. Compared with CEI, IEB decreased risk of breakthrough pain by 38% (risk ratio [95% confidence interval {CI}] of 0.62 [0.48, 0.81]; P=0.0004; I²=47%; 1164 patients) and reduced AUC of pain during the 4 h interval by 32.9% (mean difference [95% CI] of -16.7 mm h^-1 [-18.9, -14.4]; P<0.0001; 1638 patients). Intermittent epidural bolus enhanced maternal satisfaction, shortened labour duration, decreased motor block, and reduced local anaesthetic consumption. The difference between the two groups was not statistically significant for epidural side-effects or mode of delivery. The TSA indicated adequate power for reliable inferences.

CONCLUSIONS

Intermittent epidural bolus provides improved labour pain control during the first 4 h after epidural initiation with less breakthrough pain. Moderate- to high-quality evidence of intermittent epidural bolus superiority support its use as a safe and effective continuous epidural infusion alternative for labour analgesia.