Programmed intermittent epidural bolus vs. patient-controlled epidural analgesia for maintenance of labour analgesia: a two-centre, double-blind, randomised study†

Efficacy and Safety of Epidural Chloroprocaine for Breakthrough Pain During Labor Analgesia: A Prospective, Double-Blind, Randomized Trial

INTRODUCTION

A significant number of women who undergo neuraxial labor analgesia experience breakthrough pain. Prompt mitigation of breakthrough pain is essential to improve maternal and fetal outcomes. We evaluated epidural chloroprocaine compared with ropivacaine in alleviating labor breakthrough pain.

METHODS

We performed a double-blind randomized controlled clinical trial between May and July 2023. Eligible parturients received epidural analgesia with ropivacaine and sufentanil. Those with breakthrough pain were randomized to receive either 0.125% epidural ropivacaine (group R) or chloroprocaine at concentrations of 0.5% (group C1), 1.0% (group C2), or 1.5% (group C3), all in a volume of 6 mL. The primary outcome was the treatment success rate, indicated by a decrease of at least 4 points on the numerical rating scale pain score 9 min after analgesic injection. Secondary outcomes and adverse effects were also recorded.

RESULTS

Out of 323 patients receiving epidural analgesia, 192 experienced breakthrough pain. After exclusion of three patients because of protocol deviation, there were 47, 48, 47, and 47 patients in group R, C1, C2, and C3, respectively. Group C3 demonstrated a higher treatment success rate (39/47, 83.0%) in managing breakthrough pain than group R (26/47, 55.3%), group C1 (12/48, 25.0%), and group C2 (30/47, 63.8%) (p < 0.001). Group C3 had lower numerical rating scale scores at 6 and 9 min after injection and required fewer patient-controlled epidural boluses than other groups. In addition, group C3 reported greater satisfaction than the other groups (p < 0.001). No significant differences were observed in obstetric or neonatal outcomes across these groups.

CONCLUSION

Parturients experiencing breakthrough pain could receive 1.5% epidural chloroprocaine, rather than lower chloroprocaine concentrations and ropivacaine, to achieve more rapid and better pain relief with higher patient satisfaction.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2300071069, http://www.chictr.org.cn/index.aspx .

Optimum programmed intermittent epidural bolus interval time of ropivacaine 0.0625% with dexmedetomidine 0.4 μg/ml at a fixed volume of 10 mL: a randomized controlled trial

Background

The aim of our study was to administer adequate local anesthetic in programmed intermittent epidural bolus (PIEB) to avoid breakthrough pain and decrease the use of manual and PCEA boluses. We, therefore, conducted this study to determine the effective PIEB interval time between boluses of ropivacaine 0.0625% with dexmedetomidine 0.4 μg/ml at a fixed volume of 10 mL in 90% of subjects (EI90), without the use of patient-controlled epidural analgesia (PCEA).

Methods

A total of 80 subjects were included in the final statistical analysis from 23 August 2022 to 22 November 2022. The subjects were randomly assigned to one of four different PIEB time intervals: 40, 50, 60, and 70 min (groups 40, 50, 60, and 70), respectively. The primary outcome was the effective epidural labor analgesia, defined as no use of PCEA bolus or a manual bolus until the end of the first stage of labor or within 6 hours after loading dose administration. The PIEB EI90 (95% CI) between boluses of ropivacaine 0.0625% with dexmedetomidine 0.4 μg/ml at a fixed volume of 10 mL was estimated using probit regression.

Results

The effective PIEB interval time between boluses of ropivacaine 0.0625% with dexmedetomidine 0.4 μg/ml at a fixed volume of 10 mL in 90% of subjects without the use of PCEA was 45.4 (35.5-50.5) minutes using probit regression. No statistical differences were found in the proportion of subjects with Bromage score > 0, hypotension, pruritus, nausea, and vomiting between groups. However, the highest sensory block (pinprick) in the 40-min group was significantly higher than that in the other groups.

Conclusion

The estimated value for EI90 for PIEB between boluses of ropivacaine 0.0625% with dexmedetomidine 0.4 μg/ml at a fixed volume of 10 mL using probit regression was 45.4 (35.5-50.5) minutes. Furthermore, future studies are warranted to be established to determine the optimal parameters for different regimens in clinical practice.

Programmed intermittent epidural bolus in maintenance of epidural labor analgesia: a literature review

Programmed intermittent epidural bolus (PIEB), administered by the infusion pump programmed to deliver boluses of epidural solution at certain intervals, is gradually gaining more attention as a technique to maintain the labor analgesia in recent years. Many studies find that it may have some advantages when compared with other methods. However, its exact effectiveness and optimal regimen are still unclear. We conducted a literature search in PubMed, Web of Science, and Cochrane Database of Systematic Reviews for studies published between January 2010 and June 2022. Of the 263 publications identified, 27 studies were included. The purpose of this review is to discuss the effects of PIEB with continuous epidural infusion (CEI) and patient-controlled epidural analgesia (PCEA) in maintenance of epidural labor analgesia on labor outcomes and elucidate the latest research progress of implementation strategies.

The Effects of Different Puncture Points on Labor Analgesia Onset: Study Protocol for a Randomized Controlled Trial

Purpose

Parturients suffer severe pain during the stages of labor, especially the first and second. Epidural anesthesia is an effective method to alleviate labor pain. L2-3, L3-4 and L4-5 spaces have been reported to be the recommendable puncture points owing to the adequate analgesia effect and high safety. However, the speed of pain alleviation via the three points has hardly been determined, which is of great importance to parturients. Thus, the aim of this study is to compare the onset time of parturients' painless uterine contraction after epidural labor analgesia through different puncture points.

Study Design and Methods

It is a prospective, randomized, controlled, and subject- and assessor-blinded study. Totally, 150 subjects scheduled for vaginal delivery are going to be randomly assigned into the L2-3 and L3-4 group. Puncture point in L2-3 group is lumbar 2-3 space, while in L3-4 group it is lumbar 3-4 space. Analgesia initiation and maintenance are the same between the two groups. Primary outcome will be percentage of painless uterine contraction 15 min after epidural labor analgesia initiation. Secondary outcomes will be the sensory blocking level, motor blocking score, adverse effects of parturients, drug liquid consumption in unit interval, apgar score and degree of satisfaction of the parturients.

Discussion

This study estimates the onset time of parturients' painless uterine contraction after epidural labor analgesia through L2-3 or L3-4 space. The results may provide a better choice to relieve labor pain as soon as possible.

Effect of programmed intermittent epidural bolus protocol on physician-administered rescue boluses of labor analgesia

Background

Prior studies have shown that programmed intermittent epidural bolus (PIEB) techniques, with or without patient-controlled epidural analgesia (PCEA) boluses, provide better pain relief, reduced motor block, and better patient satisfaction compared to continuous epidural infusion (CEI) techniques. We hypothesized that patients who had labor epidural analgesia (LEA) maintained with PIEB and PCEA would be less likely to receive a physician-administered rescue analgesia bolus compared to patients who had CEI and PCEA.

Methods

We searched our electronic medical record for patients who had CEI and PCEA from August 1, 2021 to December 31, 2021 and for patients who had PIEB and PCEA from August 2, 2022 to December 31, 2022.

Results

A total of 792 and 665 patients had maintenance of LEA with CEI/PCEA and PIEB/PCEA, respectively. A multivariate logistic regression was performed and, after adjusting for variables of interest, patients who had PIEB and PCEA were less likely to receive one or more physician-administered rescue analgesia boluses (odds ratio 0.504; 95% confidence interval 0.392, 0.649; P < 0.001) compared to patients who had CEI and PCEA.

Conclusion

PIEB/PCEA was associated with fewer physician-administered boluses of rescue analgesia compared to CEI/PCEA when used for LEA.

A randomized double-blinded study assessing the dose-response of ropivacaine with dexmedetomidine for maintenance of labor with epidural analgesia in nulliparous parturients

Background: The combination of ropivacaine and dexmedetomidine has been used as an epidural analgesic for inducing labor. However, there is limited data regarding the administration of epidural analgesia for labor maintenance, hence, this study aimed to determine the optimum concentration through dose-response curves of ropivacaine plus dexmedetomidine, which could be used along with the Programmed Intermittent Epidural Bolus (PIEB) technique. Methods: One hundred parturients were randomized into 4 groups who were administered four different doses of ropivacaine (dexmedetomidine at 0.4 μg mL-1): 0.04%, 0.06%, 0.08%, and 0.1%. The primary outcome that was determined included the proportion of patients experiencing breakthrough pain during their 1st stage of labor. Breakthrough pain was described as a visual analog scale [VAS] score of >30 mm, requiring supplemental epidural analgesia after the administration of at least one patient-controlled bolus. The effective concentration of analgesia that was used for labor maintenance in 50% (EC50) and 90% (EC90) of patients were calculated with the help of probit regression. Secondary outcomes included epidural block characteristics, side effects, neonatal outcomes, and patient satisfaction. Results: The results indicated that the proportion of patients without breakthrough pain was 45% (10/22), 55% (12/22), 67% (16/24), and 87% (20/23) for 0.04%, 0.06%, 0.08%, and 0.10% doses of the analgesic that were administered, respectively. The EC50 value was 0.051% (95% confidence interval [CI], 0.011%-0.065%) while the EC90 value was recorded to be 0.117% (95% CI, 0.094%-0.212%). Side effects were similar among groups. Conclusion: A ropivacaine dose of 0.117% can be used as epidural analgesia for maintaining the 1st stage of labor when it was combined with dexmedetomidine (0.4 μg mL-1) and the PIEB technique. Clinical Trial Register: https://www.chictr.org.cn/index.aspx, identifier ChiCTR2200059557.

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.

ED90 of epidural esketamine with 0.075% ropivacaine for labor analgesia in nulliparous parturients: a prospective, randomized and dose-finding study

Background: Because it has been reported that racemic ketamine had a local anesthetic-sparing effect when used for epidural analgesia this would suggest the likelihood of a potential advantage (less pruritus) over opioid drugs. Esketamine has greater analgesic efficacy than racemic ketamine, but the optimum dosage regimen for epidural use is undetermined. The aim of this study was to determine the ED₉₀ of epidural esketamine when coadministered with 0.075% ropivacaine for labor analgesia. Methods: A total of 65 laboring nulliparous patients were enrolled in this study from 16 March 2022 to 15 October 2022. The patients were randomly assigned to receive 0, 0.25, 0.5, 0.75 or 1.0 mg/mL esketamine with 0.075% ropivacaine epidurally. An effective response to the epidural loading dose was defined as numerical rating scale pain score ≤3 at 30 min after the end of the epidural loading dose (10 mL of the ropivacaine 0.075% solution with the added esketamine). The ED₉₀ of epidural esketamine coadministered with 0.075% ropivacaine with 95% confidence intervals for labor analgesia was determined using probit regression. Secondary outcomes and side effects were recorded. Results: The estimated value of ED₉₀ with 95% CIs for epidural esketamine with 0.075% ropivacaine was 0.983 (0.704-2.468) mg/mL. The characteristics of sensory and motor block, consumption of ropivacaine per hour, duration of first or second stage, Apgar scores did not differ among the five groups. The incidence of mild dizziness in Group esketamine 1.0 mg/mL was significantly higher than that in other groups (p < 0.05). No statistical differences were found in other side effects among groups. Conclusion: The ED₉₀ value of epidural esketamine coadministered with 0.075% ropivacaine for labor analgesia in nulliparous parturients was about 1.0 mg/mL. Furthermore, our results suggested that epidural esketamine would cause dose-dependent mild dizziness especially at doses up to 1.0 mg/mL. As a single epidural additive, esketamine may not be suitable for labor analgesia. Future studies may investigate the appropriate dosage of esketamine at slightly higher concentrations of local anesthetics or larger initial volume of analgesia, or explore other potential advantages of esketamine. Clinical Trial Registration: (https://www.chictr.org.cn/bin/project/edit?pid=159764), identifier (ChiCTR2200057662).

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.

Comparison of Opioid-Based Patient-Controlled Analgesia with Physician-Directed Analgesia in Acute Pancreatitis: A Retrospective Cohort Study

BACKGROUND

Patient-controlled analgesia (PCA) is commonly used for acute postoperative pain management. Clinicians may also use PCA in the management of acute pancreatitis (AP); however, there is limited data on its impact on patient outcomes. We aimed to characterize a cohort of patients receiving PCA therapy for pain management in AP compared to those patients receiving standard physician-directed delivery of analgesia.

METHODS

We conducted a retrospective cohort study of adult patients admitted with AP at a tertiary care center from 2008 to 2018. Exclusion criteria included patients with chronic opioid use, chronic pancreatitis and pancreatic cancer. Primary outcomes include length of stay (LOS) and time to enteral nutrition. Secondary outcomes include proportion of patients discharged with opioid and complications. Multivariate regression analysis and t-test were used for analysis.

RESULTS

Among 656 AP patients who met the criteria, patients receiving PCA (n = 62) and standard delivery (n = 594) were similar in admission pain score, Charlson Comorbidity Index, and pancreatitis severity. There were significantly greater proportion of women, Caucasians and nonalcoholics who received PCA therapy (p < 0.01) than standard delivery. Multivariate regression analysis revealed that patients in the PCA group have a longer LOS (7.17 vs. 5.43 days, p < 0.007, OR 1.03; 95% CI 1.01-1.07), longer time to enteral nutrition (3.84 days vs. 2.56 days, p = 0.012, OR 1.11; 95% CI 1.02-1.20), and higher likelihood of being discharged with opioids (OR 1.94; 95% CI 1.07-3.63, p = 0.03).

CONCLUSION

The use of PCA in AP may be associated with poorer outcomes including longer LOS, time to enteral intake and a higher likelihood of being discharged with opioids.

Comparison of Continuous and Programmed Intermittent Bolus Infusion of 0.2% Ropivacaine after Ultrasound-Guided Continuous Interscalene Brachial Plexus Block in Arthroscopic Shoulder Surgery

Background

Despite the clinical effectiveness of the programmed intermittent bolus (PIB) method for epidural analgesia, evidence for this method in continuous interscalene brachial plexus block (CIBPB) is unclear. This study aimed to investigate the pain relief effect after arthroscopic shoulder surgery according to the administration method by comparing the PIB and continuous infusion methods among the administration methods of local anesthetics.

Methods

Sixty-four patients aged >19 years scheduled for elective arthroscopic shoulder surgery were enrolled and divided into two groups. Ultrasound-guided CIBPB was performed to control postoperative pain. The infusion pump was programmed so that 0.2% ropivacaine was continuously injected at 1.1 mL/h in group A, whereas in group B, 0.1 mL/h was continuously injected and 4 mL was periodically injected at 4 h intervals. In both groups, a further infusion of 4 mL of 0.2% ropivacaine was administered if the patient requested additional analgesia, and the lockout time was set at 30 min. Postoperative pain quality was assessed using a visual analog scale (VAS), and the incidence of patients requiring additional analgesics, motor blockade using a modified Bromage scale (MBS), and consumed doses of local anesthetic were assessed.

Results

The VAS and incidence of rescue analgesics were performed when the patient could communicate voluntarily after admission to the post-anesthetic care unit, and at 24 and 48 h after surgery showed no significant difference between the two groups. The MBS at 24 h after surgery was significantly higher in group B (p = 0.038). In the comparison of consumed doses of local anesthetic, group B had a significantly higher bolus injection dose (p = 0.047) and frequency of bolus use in the 24 h after surgery (p = 0.034).

Conclusion

The PIB method in CIBPB after arthroscopic shoulder surgery provided a similar analgesic effect, with a higher bolus injection dose of local anesthetic and increased motor blockade than the continuous infusion method.

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.

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.

Effect of patient-controlled epidural analgesia with and without automatic intermittent bolus on levobupivacaine consumption during labour: A single-centre prospective double-blinded randomised controlled study

BACKGROUND

During labour, the effects of adding a programmed intermittent epidural bolus (PIEB) baseline analgesic regimen to patient-controlled epidural analgesia (PCEA) remain uncertain.

METHODS

This single centre prospective double-blinded controlled study randomised nulliparous women over 35 weeks of gestational age in a PCEA + PIEB or PCEA only group. After an epidural analgesia catheter was inserted, a specific pump administered a solution of levobupivacaine 0.625 mg mL^-1, sufentanil 0.25 µg mL^-1, and clonidine 0.375 µg mL^-1. In both groups the PCEA mode delivered an 8 mL bolus with a lockout period of 8 min. In the PCEA + PIEB group, women also received a programmed 8 mL bolus every 60 min. Additional bolus were allowed if required. The primary outcome was the hourly consumption of levobupivacaine from epidural catheter placement to new-born delivery. Secondary outcome were motor block, oxytocin use, sufentanil consumption, additional bolus required, instrumental vaginal delivery, unplanned caesarean section, pain during labour and women's satisfaction.

RESULTS

Analysis included 162 and 155 women in the PCEA and PCEA + PIEB groups, respectively. The median [IQR] hourly consumption of levobupivacaine was significantly lower in the PCEA group (9.9 (7.8-12.4] mg h^-1) as compared to the PCEA + PIEB group (11.2 [7.9-14.3] mg h^-1; p = 0.046). The difference between medians was 1.3 mg h^-1 95 % CI (0.1-2.9). There was no difference between groups for secondary outcomes.

CONCLUSIONS

PCEA only modestly decreased the hourly consumption of local anaesthetic as compared to PCEA + PIEB but the difference was not clinically relevant.