Transversus abdominis plane block compared with wound infiltration for postoperative analgesia following Cesarean delivery: a systematic review and network meta-analysis

Peripheral nerve blocks for analgesia following cesarean delivery A narrative review

Spinal and epidural blocks are commonly employed for pain relief during and following cesarean section. Intrathecal morphine (ITM) has been the gold standard for the same for many years. In recent times, many peripheral nerve blocks (PNBs) have been tried for postoperative analgesia following cesarean delivery (PACD). This article has reviewed the common PNBs used for PACD. The role of PNBs along with ITM has been studied and the current best strategy for PACD has also been explored. Currently, Ilio-inguinal nerve and anterior transversus abdominis plane block in conjunction with intrathecal morphine have been found to be the most effective strategy, providing lower rest pain at 6 hours as compared to ITM alone. In patients not receiving intrathecal morphine, recommended PNBs are lateral transversus abdominis plane block, single shot local anesthetic wound infiltration, or continuous wound infiltration with catheter below rectus fascia. PNBs are recommended for PACD. They have an opioid-sparing effect and are devoid of adverse effects associated with central neuraxial blocks such as hypotension, bradycardia, and urine retention. However, caution must be observed with PNBs for possible local anesthetic toxicity due to the large volumes of drug required.

Continuous wound infusion catheter as part of a multimodal analgesia regimen for post-Caesarean delivery pain: a quality improvement impact study

Background

The role of continuous wound infusion catheters as part of a multimodal analgesia strategy after Caesarean delivery is unclear. We introduced continuous wound infusion catheters to our multimodal analgesia regimen to evaluate the impact on analgesic outcomes after Caesarean delivery.

Methods

After institutional review board (IRB) approval, a 4-month practice change was instituted as a quality improvement initiative. In addition to multimodal analgesia, continuous wound infusion catheters for up to 3 days were offered on alternate weeks for all women undergoing Caesarean deliveries. The primary outcome was postoperative in-hospital opioid consumption. Secondary outcomes were static and dynamic pain scores at 24 and 72 h, time until first analgesic request, opioid-related side-effects, length of stay, satisfaction (0-100%), and continuous wound infusion catheter-related complications.

Results

All women scheduled for Caesarean delivery (n=139) in the 4-month period were included in the analysis, with 70 women receiving continuous wound infusion catheters, and 69 in the control group. Opioid consumption (continuous wound infusion catheter group 11.3 [7.5-61.9] mg morphine equivalents vs control group 30.0 [11.3-48.8] mg morphine equivalents), pain scores (except 24 h resting pain scores which were higher in the control group 2 [1-3] vs 1.5 [0-3] in the continous wound infusion catheters group; P=0.05), side-effects, length of stay, and complications were similar between groups. Satisfaction scores at 24 h were higher with continuous wound infusion catheters (100% [91-100%] vs 90% [86-100%]; P=0.003) with no differences at 72 h. One patient demonstrated symptoms of systemic local anaesthetic toxicity which resolved without significant harm.

Conclusions

The addition of continuous wound infusion catheters to a multimodal analgesia regimen for post-Caesarean delivery pain management demonstrated minimal clinically significant analgesic benefits. Future studies are needed to explore the use of continuous wound infusion catheters in populations that may benefit most from this intervention.

Surgical transversus abdominis plane block with liposomal bupivacaine at cesarean: a pilot randomized trial

BACKGROUND

Postcesarean pain control is challenging. In addition to intrathecal morphine, recent studies have shown that liposomal bupivacaine administered via conventional transversus abdominis plane block reduces postcesarean opioid use. However, whether the administration of liposomal bupivacaine via a surgical approach also reduces opioid use is unknown.

OBJECTIVE

This study aimed to investigate whether the administration of liposomal bupivacaine via surgical transversus abdominis plane block (TAP block) reduces the cumulative dose of opioids administered in the first 48 hours after cesarean delivery among participants who also receive intrathecal morphine.

STUDY DESIGN

This was a pilot single-blind randomized controlled trial of 60 parturients undergoing cesarean delivery at a community tertiary referral hospital staffed by academic physicians. Immediately before fascial closure during cesarean delivery, a total of 80 mL of dilute bupivacaine plus liposomal bupivacaine or dilute bupivacaine alone was administered via surgical transversus abdominis plane block (40 mL on each side). The primary outcome was a median cumulative opioid dose received within the first 48 hours after cesarean delivery measured in morphine milligram equivalents. In addition, opioid use at other time points, pain scores, and participant satisfaction were assessed. A sample size of 60 was determined to be adequate to inform a potential future adequately powered randomized trial. The primary outcome of morphine milligram equivalents and pain scores were compared using a Wilcoxon rank-sum test.

RESULTS

Between October 11, 2021, and August 29, 2022, 60 participants were randomized and analyzed: 31 were allocated to liposomal bupivacaine plus regular bupivacaine (intervention group), and 29 were allocated to regular bupivacaine alone (control group). Participants allocated to the intervention group used a median cumulative dose of 2 morphine milligram equivalents of opioids (interquartile range, 0-24) in the first 48 hours compared with 8 morphine milligram equivalents (interquartile range, 0-40) among participants allocated to the control group (P=.236). The percentage of participants who used ≤15 morphine milligram equivalents of opioids was 61% in the intervention arm and 41% in the control arm (P=.123), and the percentage who used zero opioids was 45% in the intervention arm and 34% in the control arm (P=.399). The total number of opioid pills prescribed at discharge was fewer in the intervention arm than in the control arm (P=.029). Patient satisfaction with the intervention group and control group was similar.

CONCLUSION

Our pilot study suggests that liposomal bupivacaine administered via surgical transversus abdominis plane block is worth critical evaluation as an adjunctive analgesic modality in an adequately powered randomized trial.

Regional Analgesia for Cesarean Delivery: A Narrative Review Toward Enhancing Outcomes in Parturients

Introduction

With the current surge on peripheral nerve blocks in post-cesarean pain management and the historical lack of unequivocal evidence supporting its universal use, this review intended to re-examine the extended scope of literature on regional anesthesia and postoperative analgesia in low-transverse cesarean section.

Methods

A literature search was conducted up to April 2023 using PubMed to identify articles relevant to our search words "cesarean section", "neuraxial morphine", "post-cesarean analgesia", as well as the name of each individual nerve block. The literature search was ultimately narrowed to systematic reviews and randomized controlled trials published between 2012 and 2023. We define, describe, and discuss the evidence surrounding each individual regional anesthetic technique in the presence and absence of intrathecal morphine, which is used as the gold standard when appropriate.

Results

In the absence of neuraxial morphine, all regional anesthetic techniques have some level of analgesic benefit in the post-cesarean analgesia. Transversus Abdominis Plane blocks continue to have the most studies in their use. Newer fascia plane blocks including the anterior Quadratus Lumborum, and Erector Spinae Plane blocks provide significant analgesia. In addition, direct comparison among peripheral nerve blocks consistently favors the more proximal, centralized techniques. Conversely, in the presence of neuraxial morphine, no peripheral anesthetic technique has reliably and reproducibly demonstrated an added analgesic benefit regardless of the peripheral nerve block technique or location of local anesthetic injection in the post-cesarean population.

Conclusion

Neuraxial morphine continues to be the gold standard for post-cesarean section analgesia, the benefit of additional single injection regional anesthetic is currently not evidence supported. In cases where neuraxial opioids have not or cannot be given, there is overwhelming evidence that regional anesthetic techniques improve post-cesarean section analgesia and decrease post-operative opioid consumption. Even though there is no consensus on the optimal peripheral nerve block, emerging evidence suggests more centralized abdominal fascia plane block trends towards better analgesia.

What Is New in Obstetric Anesthesia: The 2021 Gerard W. Ostheimer Lecture

The Gerard W. Ostheimer lecture is given annually to members of the Society for Obstetric Anesthesia and Perinatology. This lecture summarizes new and emerging literature that informs the clinical practice of obstetric anesthesiologists. In this review, some of the most influential articles discussed in the 2021 virtual lecture are highlighted. Themes include maternal mortality; disparities and social determinants of health; cognitive function, mental health, and recovery; quality and safety; operations, value, and economics; clinical controversies and dogmas; epidemics and pandemics; fetal-neonatal and child health; general clinical care; basic and translational science; and the future of peripartum anesthetic care. Practice-changing evidence is presented and evaluated. A priority list for clinical updates, systems, and quality improvement initiatives is presented.

Intraperitoneal instillation versus wound infiltration for postoperative pain relief after cesarean delivery: A prospective, randomized, double-blind, placebo-controlled trial

AIM

To compare local anesthetic wound infiltration with intraperitoneal instillation of local anesthetic for analgesia after cesarean section under spinal anesthesia.

METHODS

This study was conducted on 150 pregnant women undergoing elective cesarean section under spinal anesthesia. Spinal anesthesia was performed with 7 mg isobaric bupivacaine and 15 μcg fentanyl. The patients were randomized into three groups of 50 patients each: Group local anesthetic wound infiltration (LWI): 20 ml local anesthetic solution (10 ml 0.5% bupivacaine and 10 ml 2% lidocaine mixture) was administered subcutaneous wound infiltration at the end of surgery prior to skin closure and 20 ml saline was instilled into the uterine peritoneal area before fascia closure. Group intraperitoneal local anesthetic (IPLA): 20 ml local anesthetic solution (10 ml 0.5% bupivacaine and 10 ml 2% lidocaine mixture) was instilled into the uterine peritoneal area and 20 ml saline was administered subcutaneous wound infiltration. Group Placebo: 20 ml saline was instilled into the uterine peritoneal area and 20 ml saline was administered local subcutaneous wound infiltration. Pain scores at rest and on movement, total fentanyl consumption at 24 h, maternal satisfaction, and the time to first analgesic request were recorded.

RESULTS

No statistically significant difference was observed in the postoperative pain scores at rest at 2, 12, and 24 h (p = 0.314, 0.343, and 0.735, respectively) and on movement at 12 and 24 h (p = 0.318 and 0.642, respectively) between the groups. The pain scores on movement at 2 h were significantly lower in Group IPLA compared with Group Placebo (p = 0.047). There were no significant differences between the groups in terms of total fentanyl consumption and the time to first analgesic request.

CONCLUSION

The use of intraperitoneal instillation of bupivacaine and lidocaine reduces early the pain score on movement in women undergoing cesarean section under spinal anesthesia.

Post-cesarean section analgesia

Worldwide, the most performed surgical intervention is cesarean section. Hence, post-cesarean pain is a common problem with significant health and economic impact on the individual patient and society. Adequate treatment of post-cesarean pain is necessary to facilitate enhanced recovery, improve neonatal outcome by improving breastfeeding success and bonding between mother and child, and reduce pain-induced side effects. Therefore, optimal pain relief is important, but in the obstetric population, this is often complex due to the interplay of mother and neonate. To facilitate recovery and temper the side effects of potent analgesic drugs such as opioids, multimodal analgesia is currently advocated, and clear international guidelines and recommendations have recently been described. In the present overview, we will discuss the most recent guidelines and evaluate various analgesic interventions.

Postoperative Analgesic Effectiveness of Peripheral Nerve Blocks in Cesarean Delivery: A Systematic Review and Network Meta-Analysis

The purpose of this systematic review and network meta-analysis was to determine the analgesic effectiveness of peripheral nerve blocks (PNBs), including each anatomical approach, with or without intrathecal morphine (ITMP) in cesarean delivery (CD). All relevant randomized controlled trials comparing the analgesic effectiveness of PNBs with or without ITMP after CD until July 2021. The two co-primary outcomes were designated as (1) pain at rest 6 h after surgery and (2) postoperative cumulative 24-h morphine equivalent consumption. Secondary outcomes were the time to first analgesic request, pain at rest 24 h, and dynamic pain 6 and 24 h after surgery. Seventy-six studies (6278 women) were analyzed. The combined ilioinguinal nerve and anterior transversus abdominis plane (II-aTAP) block in conjunction with ITMP had the highest SUCRA (surface under the cumulative ranking curve) values for postoperative rest pain at 6 h (88.4%) and 24-h morphine consumption (99.4%). Additionally, ITMP, ilioinguinal-iliohypogastric nerve block in conjunction with ITMP, lateral TAP block, and wound infiltration (WI) or continuous infusion (WC) below the fascia also showed a significant reduction in two co-primary outcomes. Only the II-aTAP block had a statistically significant additional analgesic effect compared to ITMP alone on rest pain at 6 h after surgery (−7.60 (−12.49, −2.70)). In conclusion, combined II-aTAP block in conjunction with ITMP is the most effective post-cesarean analgesic strategy with lower rest pain at 6 h and cumulative 24-h morphine consumption. Using the six described analgesic strategies for postoperative pain management after CD is considered reasonable. Lateral TAP block, WI, and WC below the fascia may be useful alternatives in patients with a history of sensitivity or severe adverse effects to opioids or when the CD is conducted under general anesthesia.

Transversus abdominis plane block versus local anaesthetic wound infiltration for analgesia after caesarean section: A systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Transversus abdominis plane (TAP) block and local anaesthetic wound infiltration are used to relieve pain after caesarean section.

OBJECTIVES

To determine whether TAP block or local anaesthetic wound infiltration is the better analgesic option after caesarean section.

DESIGN

Systematic review and meta-analysis with trial sequential analysis.

DATA SOURCES

MEDLINE, Embase, Cochrane Central Register of Controlled Clinical Trials, Web of Science up to June 2020.

ELIGIBILITY CRITERIA

We retrieved randomised controlled trials comparing TAP block with wound infiltration after caesarean section. Primary outcome was pain score during rest (analogue scale, 0 to 10) at 2 h postoperatively, analysed according to the TAP block technique (ultrasound-guided/landmark-guided), anaesthetic strategy (spinal/general), intrathecal fentanyl (yes/no) and multimodal analgesia (yes/no). Secondary pain-related outcomes included pain scores during rest at 12 and 24 h, and total intravenous morphine consumption at 2, 12 and 24 h. We sought rates of block complications, including postoperative infection, haematoma, visceral injury and local anaesthetic systemic toxicity.

RESULTS

Seven trials, totalling 475 patients, were identified. There was no difference in pain score during rest at 2 h between groups. Subgroup analyses revealed no differences related to TAP block technique (P = 0.64), anaesthetic strategy (P = 0.53), administration of intrathecal fentanyl (P = 0.59) or presence of multimodal analgesia (P = 0.57). Pain score during rest at 12 h and intravenous morphine consumption at 2 and 12 h were identical in both groups. Data were insufficient to compare block complications. Overall quality of evidence was moderate.

CONCLUSION

There is moderate level evidence that TAP block and wound infiltration provide similar postoperative analgesia after caesarean section.

TRIAL REGISTRY NUMBER

PROSPERO CRD42020208046.

Wound Infusion of 0.35% Levobupivacaine Reduces Mechanical Secondary Hyperalgesia and Opioid Consumption After Cesarean Delivery. A Prospective, Randomized, Triple-Blind, Placebo-Controlled Trial

BACKGROUND

Some patients still report moderate-to-severe postoperative pain after cesarean delivery. Local anesthetic wound infusion improves acute pain and might act on peripheral and central sensitization mechanisms; however, no studies have proved this hypothesis. We evaluated the potential benefits of continuous wound infusion of levobupivacaine after cesarean delivery on secondary hyperalgesia (primary end point) and primary hyperalgesia, pain relief, persistent pain, and inflammatory and metabolic stress response.

METHODS

Healthy women scheduled for elective cesarean delivery participated in this prospective, randomized, triple-blind, placebo-controlled trial (NCT01458431). All patients received spinal anesthesia with 0.5% hyperbaric bupivacaine with fentanyl and a multiholed wound catheter placed under the fascia. Women were randomized to receive continuous wound infusion (0.35% levobupivacaine 7 mL/h for 48 hours; group L) or an equal volume of saline (group S). Secondary hyperalgesia to punctate mechanical stimuli was evaluated using dynamic tests, and primary hyperalgesia was evaluated using an electronic von Frey anesthesiometer; both were assessed at 24, 48, and 72 hours. The following variables were collected: intensity of postoperative parietal and visceral pain at rest and on movement rated on a visual analog scale >72 hours, time to first bolus of patient-controlled analgesia (PCA), cumulative dose of rescue morphine (PCA) and acetaminophen, ability to sleep and sleep quality, and patient satisfaction. Persistent postoperative pain was evaluated during a telephone interview at 1, 3, 6, and 12 months after surgery. C-reactive protein, acid glycoprotein, preprandial glucose, insulin, cortisol, prolactin, growth hormone, and interleukin-6 were measured before cesarean delivery and at 8, 24, and 48 hours. Adverse events and patient outcomes were recorded.

RESULTS

Seventy women were included. In group L, the area of secondary hyperalgesia was significantly reduced (43.4 [18.5-80] vs 68.4 [39.0-136] cm2 and 45.1 [0.9-89.8] vs 67.3 [31.3-175] cm2 at 24 and 48 hours, respectively; group:time interaction P value < .001), the mechanical pain threshold was significantly higher at 24 hours (633 [441-802] vs 417 [300-572] g.mm-2; P = .001), and morphine consumption was significantly lower at 24 hours (4 [2-11] vs 11[6-23]; P = .003) compared with group S. Levobupivacaine had no effect on persistent postoperative pain at 1, 3, 6, and 12 months. Plasma insulin levels in the immediate postoperative period and at 8, 24, and 48 hours were significantly lower in group L (P < .001). There were no significant differences in other biochemical parameters of inflammatory and endocrine-metabolic response.

CONCLUSIONS

Levobupivacaine wound infusion provides adequate analgesia and might be an effective antihyperalgesic adjunct.

Efficacy of regional blocks or local anaesthetic infiltration for analgesia after caesarean delivery: a network meta-analysis of randomised controlled trials

Caesarean delivery is common and can cause severe postoperative pain but injection of local anaesthetic at various sites for regional blocks or local anaesthetic infiltration may reduce this. We aimed to compare and rank these sites. We searched PubMed, Google Scholar, EMBASE and CENTRAL to June 2021 for randomised controlled trials and performed a random-effects Bayesian model network meta-analysis. The primary outcome was dose of parenteral morphine equivalents in the first 24 postoperative hours. We used surface under cumulative ranking probabilities to order techniques. We analysed 114 trials (8730 participants). The ordered mean (95% credible interval) reduction in morphine equivalents, from 34 mg with placebo, were as follows: ilio-inguinal 15 (1-32) mg; ilio-inguinal-iliohypogastric 13 (6-19) mg; transversalis fascia 11 (4-26) mg; erector spinae 11 (10-32); transverse abdominis 9 (4-13) mg; wound catheter infusion 8 (2-15) mg; quadratus lumborum 8 (1-15) mg; wound infiltration 8 (2-13) mg; and no intervention -4 (-10 to 2) mg. Ordered efficacies for injection sites were different for other relevant outcomes, including pain (to 4-6 h and to 24 h) and time to rescue analgesia: there was no single preferred route of injection. The ordered mean (95% credible interval) reduction in dynamic pain scores (0-10 scale) at 24 h compared with placebo were as follows: wound infusion 1.2 (0.2-2.1); erector spinae 1.3 (-0.5 to 3.1); quadratus lumborum 1.0 (0.1-1.8); ilio-inguinal-iliohypogastric 0.6 (-0.5 to 1.8); transverse abdominis 0.6 (-0.1 to 1.2); wound infiltration 0.5 (-0.3 to 1.3); transversalis fascia -0.8 (-3.4 to 1.9); ilio-inguinal -0.9 (-3.6 to 1.7); and no intervention -0.8 (-1.8 to 0.2). We categorised our confidence in effect sizes as low or very low.

Evaluation of the Postoperative Analgesic Effect of 2 Different Blocks after Pediatric Circumcision Surgery

BACKGROUND

Circumcision is a painful day-case surgery. Regional anesthesia techniques are used effectively for anesthesia and postoperative analgesia after pediatric circumcision surgery.

OBJECTIVE

Our prospective observational study aimed to compare postoperative analgesic efficiency of a dorsal penile nerve (DPN) block with a transversus abdominis plane (TAP) block after male pediatric circumcision surgery and complications related to each block.

STUDY DESIGN

We enrolled 80 male children under the age of 10 years with American Society of Anesthesiologists I-II status scheduled for circumcision in this prospective observational study. A TAP or DPN block was performed after induction of general anesthesia before surgery with ultrasound (US) guidance. Postoperative pain was assessed with Faces Pain Scale-Revised and the Faces, Legs, Activity, Cry and Consolability scale.

RESULTS

There was no statistically significant difference between the groups regarding 30-min pain score levels (p > 0.05). But, the 1st hour, 2nd hour, 6th hour, 12th hour, and 24th-hour pain score levels in the TAP block group were statistically significantly higher than those of the DPN block group (p < 0.05). The 1st rescue analgesic requirement in the TAP block group was at the 6th hour postoperative. There was no need for rescue analgesia in the DPN block group during the postoperative 24-h follow-up.

DISCUSSION

A US-guided DPN block provided effective and long-lasting postoperative analgesia for circumcision surgery with statistically significantly lower pain score levels than a US-guided TAP block.

CONCLUSION

This study found that a TAP block alone was insufficient to provide adequate postoperative analgesia for circumcision surgery compared to DPN block.

Comparison of the analgesic effects of two quadratus lumborum blocks (QLBs), QLB type II vs QLB type III, in caesarean delivery: A randomised study

BACKGROUND

Quadratus lumborum blocks (QLBs) are relatively novel regional anaesthesia techniques, and the efficacy of all three types of QLB for postoperative analgesia in caesarean delivery (CD) has been demonstrated in separate studies. The aim of the present study is to compare the analgesic efficacy of the QLB-II and QLB-III blocks performed at the end of surgery in patients undergoing spinal anaesthesia for CD.

METHODS

We conducted a comparative, blinded, prospective, randomised and efficiency study. A total of 80 patients scheduled for elective CD under spinal anaesthesia were randomly allocated to receive either bilateral ultrasound-guided QLB-II or QLB-III block in a 1:1 ratio. The primary outcome was opioid consumption administered by a patient-controlled analgesia in the first 24 hours postoperatively. The secondary outcome of the study was pain intensity. Also, the time of first opioid requirement and the presence of nausea and vomiting were recorded.

RESULTS

Morphine consumption was statistically significantly lower in the QLB-III group when compared with the QLB-II group at the 3rd, 6th, 12th and 24th hours (P < .001, P < .001, P = .004, and P = .015, respectively). The QLB-III group showed significantly lower pain scores at rest at the 1st, 3rd, 6th, 9th and 24th hours after surgery (P < .001, P < .001, P < .001, P = .007 and P < .001, respectively). The QLB-III group also showed significantly lower pain score on movement at all measurement times (P < .001).

CONCLUSIONS

The analgesic efficacy of QLB-III was superior to QLB-II in patients who had undergone CD under spinal anaesthesia without use of intrathecal opioids and nonsteroidal anti-inflammatory drugs.

The Current Consideration, Approach, and Management in Postcesarean Delivery Pain Control: A Narrative Review

Optimal postoperative analgesia has a significant impact on patient recovery and outcomes after cesarean delivery. Multimodal analgesia is the core principle for cesarean delivery and pain management. For a standard analgesic regimen, the use of long-acting neuraxial opioids (e.g., morphine) and adjunct drugs, such as scheduled acetaminophen and nonsteroidal anti-inflammatory drugs, is recommended unless contraindicated. Oral or intravenous opioids should be reserved for breakthrough pain. In addition to the aforementioned use of multimodal analgesia, preoperative evaluation is critical to individualize the analgesic regimen according to the patient requirements. Risk factors for severe postoperative pain or analgesia-related adverse effects will require modifications to the standard analgesic regimen (e.g., the use of ketamine, gabapentinoids, or regional anesthetic techniques). Further investigation is required to determine analgesic drugs or dose alterations based on preoperative predictions for patients at risk of severe pain. Outcomes beyond pain and analgesic use, such as functional recovery, should be determined to evaluate analgesic treatment protocols.

Role of regional anesthesia in Enhanced Recovery After Surgery (ERAS) protocols

PURPOSE OF REVIEW

Enhanced Recovery After Surgery (ERAS) protocols and interventional locoregional anesthesia (LRA) techniques continuously evolve. This review outlines the latest recommendations for the use of regional anesthesia in ERAS protocols and emerging interventional analgesia techniques.

RECENT FINDINGS

Research in ultrasound-guided regional anesthesia has led to a refinement of the traditional techniques and the introduction of a number of new approaches to complement ERAS strategies. The efficacy and versatility of LRA enable its use in an increasing number of ERAS indications.

SUMMARY

The implementation of ERAS protocols in different surgical procedures reduces overall complications and recovery time. Multimodal analgesia strategies with regional anesthesia techniques are some of the key interventions contributing to the improvement in postoperative outcomes.

The Efficacy and Safety of Local Anesthetic Techniques for Postoperative Analgesia After Cesarean Section: A Bayesian Network Meta-Analysis of Randomized Controlled Trials

Objective

Cesarean section (CS) is one of the most frequently performed major surgical interventions. Local anesthetic techniques, a universal component of perioperative multimodal analgesia, are reportedly effective in reducing pain scores and opioid requirements. However, the optimal local anesthetic technique for postoperative CS pain remains unclear.

Methods

Six databases were searched, and a Bayesian network meta-analysis was performed. The outcomes included cumulative morphine consumption and pain scores at four time points, time to first analgesic request, postoperative nausea and vomiting, pruritus, and sedation.

Results

Sixty-eight studies with 5039 pregnant women were included. Six local anesthetic techniques were involved, including transversus abdominis plane block (TAPB), ilioinguinal and iliohypogastric nerve block, quadratus lumborum blocks, transversalis fascia plane block, erector spinae block, and wound infiltration. Compared to inactive controls, TAPB reduced cumulative morphine consumption at 6, 12, 24, and 48 h, pain scores at 6, 12, and 24 h (with the exception of 24 h at rest), the risk of postoperative nausea and vomiting, and sedation. Compared with inactive controls, ilioinguinal and iliohypogastric nerve block reduced cumulative morphine consumption at 6 and 24 h and pain scores at 6, 12, and 24 h during movement. Compared with inactive controls, quadratus lumborum blocks reduced cumulative morphine consumption at 24 and 48 h and pain scores at 6 and 12 h and lengthened the time to first analgesic request. Compared with inactive controls, wound infiltration reduced cumulative morphine consumption at 12 and 24 h, pain scores at 12 and 24 h during movement, and risk of sedation. Compared with inactive controls, erector spinae block reduced pain scores at 6 and 12 h. Transversalis fascia plane block was found to have similar outcomes to inactive controls.

Conclusion

TAPB is the most comprehensive local anesthetic technique for postoperative CS analgesia in the absence of intrathecal morphine.

Regional anaesthesia for labour, operative vaginal delivery and caesarean delivery: a narrative review

This narrative review discusses recent evidence surrounding the use of regional anaesthesia in the obstetric setting, including intrapartum techniques for labour and operative vaginal delivery, and caesarean delivery. Pudendal nerve blockade, ideally administered by an obstetrician, should be considered for operative vaginal delivery if neuraxial analgesia is contraindicated. Regional techniques are increasingly utilised in clinical practice for caesarean delivery to minimise opioid consumption, reduce pain, improve postpartum recovery and facilitate earlier discharge as part of enhanced recovery protocols. The evidence surrounding transversus abdominis plane and quadratus lumborum blockade supports their use when: long-acting neuraxial opioids cannot be administered due to contraindications; if emergency delivery necessitates general anaesthesia; or as a postoperative rescue technique. Current data suggest quadratus lumborum blockade is no more effective than transversus abdominis plane blockade after caesarean delivery. Transversus abdominis plane blockade, wound catheter insertion and single shot wound infiltration are all effective techniques for reducing postoperative opioid consumption, with transversus abdominis plane blockade favoured, followed by wound catheters and then wound infiltration. Ilio-inguinal and iliohypogastric, erector spinae plane and rectus sheath blockade all require further studies to determine their efficacy for caesarean delivery in the presence or absence of long-acting neuraxial opioids. Future studies are needed to: compare approaches for individual techniques; determine which combinations of techniques and dosing regimens result in optimal analgesic and recovery outcomes following delivery; and elucidate the populations that benefit most from regional anaesthesia in the obstetric setting.

PROSPECT guideline for elective caesarean section: updated systematic review and procedure-specific postoperative pain management recommendations

Caesarean section is associated with moderate‐to‐severe postoperative pain, which can influence postoperative recovery and patient satisfaction as well as breastfeeding success and mother‐child bonding. The aim of this systematic review was to update the available literature and develop recommendations for optimal pain management after elective caesarean section under neuraxial anaesthesia. A systematic review utilising procedure‐specific postoperative pain management (PROSPECT) methodology was undertaken. Randomised controlled trials published in the English language between 1 May 2014 and 22 October 2020 evaluating the effects of analgesic, anaesthetic and surgical interventions were retrieved from MEDLINE, Embase and Cochrane databases. Studies evaluating pain management for emergency or unplanned operative deliveries or caesarean section performed under general anaesthesia were excluded. A total of 145 studies met the inclusion criteria. For patients undergoing elective caesarean section performed under neuraxial anaesthesia, recommendations include intrathecal morphine 50–100 µg or diamorphine 300 µg administered pre‐operatively; paracetamol; non‐steroidal anti‐inflammatory drugs; and intravenous dexamethasone administered after delivery. If intrathecal opioid was not administered, single‐injection local anaesthetic wound infiltration; continuous wound local anaesthetic infusion; and/or fascial plane blocks such as transversus abdominis plane or quadratus lumborum blocks are recommended. The postoperative regimen should include regular paracetamol and non‐steroidal anti‐inflammatory drugs with opioids used for rescue. The surgical technique should include a Joel‐Cohen incision; non‐closure of the peritoneum; and abdominal binders. Transcutaneous electrical nerve stimulation could be used as analgesic adjunct. Some of the interventions, although effective, carry risks, and consequentially were omitted from the recommendations. Some interventions were not recommended due to insufficient, inconsistent or lack of evidence. Of note, these recommendations may not be applicable to unplanned deliveries or caesarean section performed under general anaesthesia.