Transversus abdominis plane block vs. wound infiltration in Caesarean section: a randomised controlled trial

To assess the analgesic efficacy of adjuvant magnesium sulfate added with ropivacaine over ropivacaine alone as a continuous infiltration in total abdominal hysterectomy wound: A randomized controlled trial

Background and Aims

Magnesium sulfate (MgSO4) has been demonstrated to have analgesic property in various clinical settings. This study explores if addition of MgSO4 to ropivacaine increases its analgesic efficacy when infiltrated continuously in the postsurgical wound following total abdominal hysterectomy.

Material and Methods

This randomized controlled trial was conducted at a tertiary care referral hospital in New Delhi, India. Fifty-two patients were randomized into two groups to receive the intervention of which 48 were able to complete the study. The first group (n = 26) received 0.25% ropivacaine infiltration and the second group (n = 26) received 0.25% ropivacaine with 5% MgSO4 at the incision site for 48 h postoperatively. Primary objective was to compare the total postoperative opioid (morphine) consumption by the study participants in both the groups and the secondary objectives were pain scores at rest and at movement, patient satisfaction score, and wound quality of life on the 7th postoperative day among the two groups.

Results

Both the groups were comparable in their demographic characteristics. The median morphine consumed at 48 h postoperatively was 16.5 [0-77] mg in the ropivacaine group and 13[1-45] mg in the ropivacaine with MgSO4 group and the difference was statistically insignificant (P = 0.788). There was no statistical difference between the groups with respect to the pain scores, patient satisfaction, or wound quality of life at 7 days.

Conclusion

The addition of MgSO4 to ropivacaine does not confer any additional postoperative analgesic benefits over ropivacaine alone in continuous wound infiltration following total abdominal hysterectomy.

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.

Peripheral Nerve Blocks for Cesarean Delivery Analgesia: A Narrative Review

Effective postoperative analgesia using multimodal approach improves maternal and neonatal outcomes after cesarean delivery. The use of neuraxial approach (local anesthetic and opioids) and intravenous adjunctive drugs, such as nonsteroidal anti-inflammatory drugs and acetaminophen, currently represents the standard regimen for post-cesarean delivery analgesia. Peripheral nerve blocks may be considered in patients who are unable to receive neuraxial techniques; these blocks may also be used as a rescue technique in selected patients. This review discusses the relevant anatomy, current evidence, and advantages and disadvantages of the various peripheral nerve block techniques. Further research is warranted to compare the analgesic efficacy of these techniques, especially newer blocks (e.g., quadratus lumborum blocks and erector spinae plane blocks). Moreover, future studies should determine the safety profile of these blocks (e.g., fascial plane blocks) in the obstetric population because of its increased susceptibility to local anesthetic toxicity.

Long-Acting Bupivacaine for Pain Control After Cesarean Birth

OBJECTIVE

To evaluate women's postcesarean pain levels and total opioid use for standard opioid pain management compared with local anesthetic with patient-requested opioids.

DESIGN

Retrospective cohort study.

SETTING/LOCAL PROBLEM

Rural southeast Ohio. Ohio had a higher rate of opioid use disorder (1.4%) than both the regional average (0.8%) and the national average (0.7%).

PARTICIPANTS

We performed a retrospective study of 402 medical records of women who gave birth by caesarean.

INTERVENTION

Women were provided one of three types of perioperative anesthesia: routine spinal (standard of care group), wound infiltration with liposomal bupivacaine (LB INF), and transversus abdominis plane (TAP) block with liposomal bupivacaine (LB TAP).Data were collected on the amount of opioids taken postoperatively (measured as morphine milligram equivalents [MME]), pain scores, and history of opioid use.

RESULTS

The LB INF and LB TAP groups had significantly lower total and average MME per day than the standard of care group (p < .001). Pain scores for the LB INF group were lower on postoperative day (POD) 0 and POD1, whereas LB TAP pain scores were lower than standard of care pain scores on POD1 (p < .004). Women with a prior history of substance use disorders reported higher pain scores, took more total opioids. and stayed in the hospital longer regardless of type of anesthesia received (p < .001).

CONCLUSION

LB INF and LB TAP were associated with lower amounts of opioids used and with lower postcesarean pain scores compared with the standard of care.

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.

Posteromedial quadratus lumborum block versus wound infiltration after caesarean section: A randomised, double-blind, controlled study

BACKGROUND

Reducing pain and minimising the use of opioids after caesarean section are crucial to enhancing maternal recovery and promoting mother-newborn interaction. Various techniques have been implemented to improve analgesia. We compared the analgesic efficacy of posteromedial quadratus lumborum block with that of wound infiltration following elective caesarean section.

OBJECTIVE

We hypothesised that within a multimodal analgesia approach, posteromedial quadratus lumborum block would, due to its potential to relieve visceral pain, result in a 15% reduction in 24-h postoperative opioid consumption compared with wound infiltration.

DESIGN

A double-blind, randomised, placebo-controlled clinical study.

SETTING

A single-centre study between August 2019 and May 2020.

PATIENTS

One hundred and sixteen women were randomly allocated into two groups. In the quadratus lumborum group, 20 ml 0.9% saline was injected into the surgical wound followed by bilateral posteromedial quadratus lumborum block using 20 ml 0.25% levobupivacaine per side. In the wound infiltration group, 20 ml of 0.25% levobupivacaine was injected into the surgical wound followed by a bilateral posteromedial quadratus lumborum injection with 20 ml 0.9% saline per side.

MAIN OUTCOME MEASURES

The primary outcome was opioid (piritramide) consumption at 24 h. Secondary outcomes were piritramide consumption at 48 h, time-to-first analgesic request, pain scores at rest and with movement, surgery-to-first-ambulation time, surgery-to-breastfeeding time, sedation, pruritus and complications.

RESULTS

Piritramide consumption in 24 h was significantly lower with posteromedial quadratus lumborum block (1.5 ± 1.8 mg) than with wound infiltration (2.2 ± 1.7 mg) (P = 0.04), mean difference of -0.7 mg, (95% CI -1.3 to -0.03). In those who required piritramide, time-to-first analgesic request was significantly longer with posteromedial quadratus lumborum block 11 [7 to 14] h, than with wound infiltration 7 [5 to 11] h (P = 0.02). Pain scores were low, with no differences recorded at rest and with movement. There were no differences in time-to-ambulation and time-to-breastfeed between the groups.

CONCLUSION

As a component of multimodal post-caesarean section analgesia, posteromedial quadratus lumborum block was associated with lower 24-h opioid consumption compared with wound infiltration.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04000308.

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 Anesthesia Abdominal Blocks and Local Infiltration After Cesarean Delivery: Review of Current Evidence

PURPOSE OF REVIEW

In this review, we discuss surgical infiltration and various abdominal wall blocks, including transversus abdominis plane (TAP) block and quadratus lumborum blocks, and review the literature on the evidence behind these approaches and analgesia for cesarean delivery (CD).

RECENT FINDINGS

Adequate pain management in the parturient following CD is important to facilitate early ambulation and neonatal care while also improving patient satisfaction and decreasing hospital length of stay. Neuraxial opioids have been a mainstay for postoperative analgesia; however, this option may not be available for patients undergoing emergency CD and have contraindications to neuraxial approaches, refusing an epidural or spinal, or with technical difficulties for neuraxial placement. In such cases, alternative options include a fascial plane block or surgical wound infiltration. The use of regional blocks or surgical wound infiltration is especially recommended in the parturient who does not receive neuraxial opioids for CD. Adequate postoperative analgesia following CD is an important component of the overall care of the parturient as it helps facilitate early mobilization and improve patient satisfaction. In conclusion, the use of abdominal fascial plane blocks or surgical wound infiltration is recommended in the parturient who does not receive neuraxial opioids for CD.

European Society of Anaesthesiology and Intensive Care Guidelines on peri-operative use of ultrasound for regional anaesthesia (PERSEUS regional anesthesia): Peripheral nerves blocks and neuraxial anaesthesia

Nowadays, ultrasound-guidance is commonly used in regional anaesthesia (USGRA) and to locate the spinal anatomy in neuraxial analgesia. The aim of this second guideline on the PERi-operative uSE of UltraSound (PERSEUS-RA) is to provide evidence as to which areas of regional anaesthesia the use of ultrasound guidance should be considered a gold standard or beneficial to the patient. The PERSEUS Taskforce members were asked to define relevant outcomes and rank the relative importance of outcomes following the GRADE process. Whenever the literature was not able to provide enough evidence, we decided to use the RAND method with a modified Delphi process. Whenever compared with alternative techniques, the use of USGRA is considered well tolerated and effective for some nerve blocks but there are certain areas, such as truncal blocks, where a lack of robust data precludes useful comparison. The new frontiers for further research are represented by the application of USG during epidural analgesia or spinal anaesthesia as, in these cases, the evidence for the value of the use of ultrasound is limited to the preprocedure identification of the anatomy, providing the operator with a better idea of the depth and angle of the epidural or spinal space. USGRA can be considered an essential part of the curriculum of the anaesthesiologist with a defined training and certification path. Our recommendations will require considerable changes to some training programmes, and it will be necessary for these to be phased in before compliance becomes mandatory.

Transversus abdominis plane block versus wound infiltration for post-cesarean section analgesia: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Transversus abdominis plane (TAP) block and wound infiltration (WI) with local anesthetics are used for postoperative analgesia after cesarean section (CS), reducing the need for administration of opioids.

OBJECTIVE

To compare the analgesic effect of TAP block related to WI.

SEARCH STRATEGY

MEDLINE, Scopus, ClinicalTrials.gov, EMBASE, Cochrane Library, and CINAHL were searched from inception until April 2020.

SELECTION CRITERIA

Randomized controlled trials (RCTs) about women who underwent TAP block or WI after CS.

DATA COLLECTION AND ANALYSIS

Relevant data were extracted and tabulated. Review Manager 5.3 was used for data analysis. Primary outcome was cumulative opioid consumption (COC) 24 and 48 h after CS.

MAIN RESULTS

Five RCTs, enrolling 268 women, were included. There were no significant differences between the interventions regarding COC at 24 (mean difference [MD] -1.68, 95% confidence interval [CI] -6.29 to 2.93) and 48 hours (MD 1.28, 95% CI -10.44 to 13.00). Adverse effects (relative risk [RR] 0.93, 95% CI 0.75-1.16), gastrointestinal reactions (RR 1.30, 95% CI 0.46-3.68), or mild-moderate sedation (RR 1.12, 95% CI 0.72-1.74), pain scores, satisfaction of women, and withdrawals were similar between groups.

CONCLUSIONS

There might be no significant advantages selecting TAP block over WI for post-CS analgesia.

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.

Transversus Abdominis Plane Block versus Wound Infiltration with Conventional Local Anesthetics in Adult Patients Underwent Surgery: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Background

How to effectively control the postoperative pain of patients is extremely important to clinicians. Transversus abdominis plane (TAP) block is a novel analgesic method reported to greatly decrease postoperative pain. However, in many areas, there still exists a phenomenon of surgeons using wound infiltration (WI) with conventional local anesthetics (not liposome anesthetics) as the main means to decrease postoperative pain because of traditional wisdom or convenience. Here, we compared the analgesic effectiveness of the two different methods to determine which method is more suitable for adult patients. Materials and methods. A systematic review and meta-analysis of randomized controlled trials (RCTs) comparing TAP block and WI without liposome anesthetics in adult patients were performed. Frequently used databases were extensively searched. The main outcomes were postoperative pain scores in different situations (at rest or during movement) and the time until the first use of rescue analgesics. The secondary outcomes were postoperative nausea and vomiting (PONV) incidence and patient satisfaction scores.

Results

Fifteen studies with 983 participants met the inclusion criteria and were included in the present study. The heterogeneity in the final analysis regarding the pain score was low to moderate. The major results of the sensitivity analysis were stable. WI had the same analgesic effect as TAP block only at the one-hour postoperative time point (mean difference = -0.32, 95% confidence interval (-0.87, 0.24), P = 0.26) and was associated with a shorter time until the first rescue analgesic and poorer patient satisfaction.

Conclusion

TAP block results in a more effective and steady analgesic effect than WI with conventional local anesthetics in adult patients from the early postoperative period and obtains higher patient satisfaction.

Continuous Wound Infiltration of Local Anesthetics in Postoperative Pain Management: Safety, Efficacy and Current Perspectives

Local infiltration and continuous infusion of surgical wound with anesthetics are parts of multimodal analgesia for postoperative pain control. The techniques, given the simplicity of execution that does not increase the timing of the intervention and does not require additional technical skills, are applied in several kinds of surgeries. The continuous wound infiltration can be used for days and a variety of continuous delivery methods can be chosen, including patient-controlled analgesia, continuous infusion or intermittent bolus. The purpose of this narrative review is to analyze the literature, in particular by researching the safety, efficacy and current perspectives of continuous wound infiltration for postoperative pain management in different surgical settings. We have identified 203 articles and 95 of these have been taken into consideration: 17 for the lower limb surgery; 7 for the upper limb surgery, 51 for the laparotomy/laparoscopic surgery of the abdominopelvic area, 13 studies regarding breast surgery and 7 for cardiothoracic surgery. The analysis of these studies reveals that the technique has a variable effectiveness based on the type of structure involved: it is better in structures rich in subcutaneous and connective tissue, while the effectiveness is limited in anatomic districts with a greater variability of innervation. However, regardless the heterogeneity of results, a general reduction in pain intensity and in opioid consumption has been observed with continuous wound infiltration: it is an excellent analgesic technique that can be included in the multimodal treatment of postoperative pain or represents a valid alternative when other options are contraindicated.

Transversus Abdominis Plane Block

In this narrative review article, the authors discuss the anatomy, nomenclature, history, approaches (posterior vs. lateral vs. subcostal), techniques, pharmacology, indications, and complications of transversus abdominis plane blocks, as well as possible alternative truncal blocks.

Despite the scarcity of evidence and contradictory findings, certain clinical suggestions can nonetheless be made. Overall transversus abdominis plane blocks appear most beneficial in the setting of open appendectomy (posterior or lateral approach). Lateral transversus abdominis plane blocks are not suggested for laparoscopic hysterectomy, laparoscopic appendectomy, or open prostatectomy. However, transversus abdominis plane blocks could serve as an analgesic option for Cesarean delivery (posterior or lateral approach) and open colorectal section (subcostal or lateral approach) if there exist contraindications to intrathecal morphine and thoracic epidural analgesia, respectively.

Future investigation is required to compare posterior and subcostal transversus abdominis plane blocks in clinical settings. Furthermore, posterior transversus abdominis plane blocks should be investigated for surgical interventions in which their lateral counterparts have proven not to be beneficial (e.g., laparoscopic hysterectomy/appendectomy, open prostatectomy). More importantly, because posterior transversus abdominis plane blocks can purportedly provide sympathetic blockade and visceral analgesia, they should be compared with thoracic epidural analgesia for open colorectal surgery. Finally, transversus abdominis plane blocks should be compared with newer truncal blocks (e.g., erector spinae plane and quadratus lumborum blocks) with well-designed and adequately powered trials.

An Evaluation of the Adding Magnesium Sulfate to Ropivacaine on Ultrasound-Guided Transverse Abdominis Plane Block After Abdominal Hysterectomy

Background

Post-hysterectomy pain is extremely annoying and using transverse abdominis plane (TAP) block can be a useful method to manage postoperative pain, but its duration of effect is challenging. Magnesium sulfate increases, in some cases, the effects of local anesthetics on the peripheral nerve blocks.

Objectives

The current study aimed at investigating the effects of adding magnesium sulfate to ropivacaine in the transverse abdominis plane block after hysterectomy.

Methods

The current randomized, double blind, clinical trial, to manage postoperative pain, was conducted on a total of 60 patients, 30 - 60 years old, ASA (American Society of Anesthesiologists) class I-II undergone elective abdominal hysterectomy candidates to receive ultrasound-guided bilateral transverse abdominis abdominis plane (TAP) blocks. Patients with coagulation disorders, infection, history of any addiction, sensitivity to the local anesthetics and magnesium sulfate were excluded. The subjects were equally allocated into two groups, the control group, ropivacaine plus normal saline (R), and the study group, ropivacaine plus magnesium sulfate (RM). The injection contained 19 mL ropivacaine 0.2% plus 1 mL normal saline in the group R, and 19 mL ropivacaine 0.2% plus 1 mL magnesium sulfate 50% in the RM group on each side. As well as the patients' characteristics, the level of pain score (visual analogue scale = VAS), rescue analgesic demand (diclofenac suppository), and possible adverse effects were evaluated at 1, 2, 6, 12, and 24 hours after the operation in the two groups.

Results

The mean pain scores of the patients at the first hour after surgery were 5.7 ± 0.9 and 5.9 ± 1.1 in R and RM groups, respectively. The scores reached 2.9 ± 0.5 and 2.7 ± 0.4 at the second hour after surgery (the first post-block measurement) and 3.1 ± 0.7 and 2.8 ± 0.7 within the next 24 hours, respectively. Although the pain scores were generally lower at all hours in the RM group, none was statistically significant. The rescue analgesic consumption gradually increased in the two groups, and it was less in the study group than in the control group in the first hours after the block (second hour after surgery); however, it was not statistically significant. No adverse effects were observed in the two groups.

Conclusions

Results of the current study suggested that the addition of magnesium sulfate to ropivacaine in TAP block does not affect the post-hysterectomy pain.

Comparison of Postoperative Analgesic Efficacy of Wound Site Infiltration and Ultrasound-guided Transversus Abdominis Plane Block with 0.5% Ropivacaine in Lower Abdominal Surgeries under Spinal Anesthesia

Context

Optimization and providing excellent quality of postoperative analgesia after total abdominal hysterectomy is a determinant factor of better clinical outcome, increases patient satisfaction, and allows early mobilization of the patient.

Aims

The aim of this study is to compare the postoperative analgesic efficacy of wound site infiltration (WSI) and ultrasound-guided transversus abdominis plane block (TAPB) with 0.5% ropivacaine in lower abdominal surgeries under spinal anesthesia.

Settings and Design

This was a randomized controlled study.

Subjects and Methods

One hundred and ten patients undergoing lower abdominal surgeries were randomly allocated to two groups (WSI and TAP) of 55 patients in each. At the end of the surgical procedure, 2.5 mg/kg of the drug ropivacaine 0.5% was administered by an anesthesiologist through either of the routes of study. Visual analog score (VAS) assessment was done at every 30 min, for 1½ h, every 2 for 24 h postoperatively. Injection diclofenac sodium 75 mg intramuscularly was given whenever VAS was >3 as rescue analgesic.

Statistical Analysis Used

Epi Info 7.0 version software for Windows was used. All analyses were performed using Kolmogorov-Smirnov test. Mann-Whitney test was applied to detect the difference between the two groups. P < 0.05 was considered statistically significant.

Results

Postoperative VAS scores in Group TAP were significantly reduced at 30 min, 1^st h, 1 h 30 min, 2, 4, 6, 8, 10, 12, 18, and 24 h (P < 0.001). The total doses of rescue analgesics administered were also low in the Group TAP (1.41 ± 0.538) with P < 0.0001 in comparison to Group WSI (2.24 ± 0.637) with P < 0.001.

Conclusions

The quality of analgesia along with lesser rescue analgesic requirement and their side effects makes the TAPB, a good and safer option for lower abdominal gynecological surgeries. Both WSI and USG TAPB are effective in providing postoperative analgesia as a part of multimodal analgesia in lower abdominal surgeries. However, in our study the quality of analgesia along with lesser rescue analgesic requirement and their side effects makes the TAPB, a good and safer option for lower abdominal gynecological surgeries.

Endogenous Opiates and Behavior: 2016

This paper is the thirty-ninth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2016 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia, stress and social status, tolerance and dependence, learning and memory, eating and drinking, drug abuse and alcohol, sexual activity and hormones, pregnancy, development and endocrinology, mental illness and mood, seizures and neurologic disorders, electrical-related activity and neurophysiology, general activity and locomotion, gastrointestinal, renal and hepatic functions, cardiovascular responses, respiration and thermoregulation, and immunological responses.

Local anaesthetic wound infiltration for postcaesarean section analgesia: A systematic review and meta-analysis

BACKGROUND

Wound infiltration with local anaesthetics has been investigated as a potentially useful method for providing analgesia after caesarean delivery, but the literature is inconclusive.

OBJECTIVE

The objective is to assess the efficacy of local anaesthetic wound infiltration in reducing pain scores and opioid consumption in women undergoing caesarean delivery.

DESIGN

Systematic review of randomised controlled trials with meta-analyses.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled trials (CENTRAL) until December 2015.

ELIGIBILITY CRITERIA

Randomised controlled trials that assessed the efficacy of local anaesthetic wound infiltration using an infusion or single injection technique for postcaesarean section analgesia.

RESULTS

A total of 21 studies were included in the final analysis (11 studies using an infusion technique and 10 studies using single infiltration). Local anaesthetic wound infiltration significantly decreased opioid consumption at 24 h [mean difference -9.69 mg morphine equivalents, 95% confidence interval (CI), -14.85 to -4.52] and pain scores after 24 h at rest (mean difference -0.36, 95% CI, -0.58 to -0.14) and on movement (mean difference -0.61, 95% CI, -1.19 to -0.03). Subgroup analysis did not suggest a difference in primary outcomes between infusions and single infiltration. Opioid consumption was reduced in patients who did not receive intrathecal morphine but not in those who received intrathecal morphine, although there were very little data in patients receiving intrathecal morphine. Pain scores at rest and on movement at 24 h were reduced with catheter placement below the fascia but not above the fascia. There were no statistically significant reductions in nausea, vomiting or pruritus with local anaesthetic infiltration.

CONCLUSION

Local anaesthetic wound infiltration reduces postoperative opioid consumption but had minimal effect on pain scores and did not reduce opioid-related side-effects in women who had undergone delivery by caesarean section. The review is limited by a paucity of studies using intrathecal morphine and by the indirect comparisons performed for subgroup analyses.

Preperitoneal postcesarean section bupivacaine analgesia: Comparison between dexamethasone and dexmedetomidine as adjuvants

Background:

The peritoneal wound is frequently neglected during laparotomy. The preperitoneal local anesthetics and many adjuvants were effective for postcesarean analgesia. Analgesia may involve somatic and autonomic components. The preperitoneal bupivacaine and the promising adjuvants dexamethasone or dexmedetomidine were compared in this study.

Patients and Methods:

Sixty patients subjected to a cesarean section (CS) under general anesthesia divided into two groups using a bolus of preperitoneal bupivacaine 0.7 mg/kg with either 1ug/kg dexmedetomidine (Group P) or 8 mg dexamethasone (Group D). The time to the first analgesic request was the primary outcome.

Results:

There was a significantly prolonged time to the first analgesic request in the Group P than the Group D and less required preperitoneal injections in the Group P, also pain assessed by Numerical Rating Scale (NRS) was lower in the Group P than the Group D after 6 h postoperatively up to 24 h.

Conclusions:

Dexmedetomidine provided better analgesia than dexamethasone as an adjuvant to preperitoneal bupivacaine post-CS.

Transversus Abdominis Plane Block Versus Wound Infiltration for Analgesia After Cesarean Delivery: A Randomized Controlled Trial

BACKGROUND

Transversus abdominis plane (TAP) block and local anesthetic wound infiltration provide analgesia after cesarean delivery. Studies comparing the 2 techniques are scarce, with conflicting results. This double-blind, randomized controlled trial aimed to compare bilateral ultrasound-guided TAP block with single-shot local anesthetic wound infiltration for analgesia after cesarean delivery performed under spinal anesthesia. We hypothesized that the TAP block would decrease postoperative cumulative fentanyl consumption at 24 hours.

METHODS

Eligible subjects were American Society of Anesthesiologists physical status II parturients with full-term singleton pregnancies undergoing elective cesarean delivery under spinal anesthesia. Exclusion criteria were: <19 years of age or >40 years of age; height <150 cm, weight <60 kg, body mass index ≥40 kg/m; contraindications to spinal anesthesia; history of recent opioid exposure; hypersensitivity to any of the drugs used in the study; significant cardiovascular, renal, or hepatic disease; and known fetal abnormalities. Eighty subjects were randomly allocated to 2 equal groups. In the infiltration group, participants received 15 mL of bupivacaine 0.25% in each side of the surgical wound (total 30 mL); and in the TAP group, participants received 20 mL of bupivacaine 0.25% bilaterally in the TAP block (total 40 mL). The TAP block and wound infiltration were performed by the primary investigator and the operating obstetrician, respectively. All participants received postoperative standard analgesia (ketorolac and paracetamol) and intravenous fentanyl via patient-controlled analgesia. Patients and outcome assessors were blinded to the study group. The primary outcome was the cumulative fentanyl consumption at 24 hours. Secondary outcomes were the time to the first postoperative fentanyl dose, cumulative fentanyl consumption at 2, 4, 6, and 12 hours, pain scores at rest and on movement at 2, 4, 6, 12, and 24 hours, the deepest level of sedation, the incidence of side effects (nausea and vomiting and pruritis), and patient satisfaction.

RESULTS

Data from 78 patients (39 patients in each group) were analyzed. The mean ± SD of cumulative fentanyl consumption at 24 hours was 157.4 ± 63.4 μg in the infiltration group and 153.3 ± 68.3 μg in the TAP group (difference in means [95% confidence interval] is 4.1 [-25.6 to 33.8] μg; P = .8). There were no significant differences between the 2 groups in the time to the first postoperative fentanyl dose, cumulative fentanyl consumption at 2, 4, 6, and 12 hours, pain scores at rest and on movement at 2, 4, 6, 12, and 24 hours, the deepest level of sedation, and patient satisfaction. The incidence of side effects (nausea and vomiting and pruritis) was low in the 2 groups.

CONCLUSIONS

TAP block and wound infiltration did not significantly differ regarding postoperative fentanyl consumption, pain scores, and patient satisfaction in parturients undergoing cesarean delivery under spinal anesthesia.

Optimal Pain Management After Cesarean Delivery

Cesarean delivery rates are increasing worldwide, and effective postoperative pain management is a key priority of women undergoing cesarean delivery. Inadequate pain management in the acute postoperative period is associated with persistent pain, greater opioid use, delayed functional recovery, and increased postpartum depression. In addition to pain relief, optimal management of patients after cesarean delivery should address the goals of unrestricted maternal mobility, minimal maternal and neonatal side effects, rapid recovery to baseline functionality, and early discharge home. Multimodal analgesia should include neuraxial morphine in conjunction with nonopioid adjuncts, with additional oral or intravenous opioids reserved for severe breakthrough pain.

Comparison of the analgesic effect between continuous wound infiltration and single-injection transversus abdominis plane block after gynecologic laparotomy

PURPOSE

Both single-injection transversus abdominis plane (TAP) block and continuous wound infiltration (CWI) provide postoperative analgesia, but no study has compared the two regional techniques. We tested the hypothesis that CWI is more effective for controlling postoperative pain compared with single-injection TAP block after laparotomy.

METHODS

We conducted a prospective randomized study of patients undergoing gynecologic laparotomy with midline incision through the umbilicus under general anesthesia. The patients were allocated to receive either single-injection TAP block (TAP group) or CWI (CWI group) for postoperative analgesia. All patients received intravenous patient-controlled analgesia with morphine and intravenous flurbiprofen twice daily after surgery. Postoperative pain at rest and on coughing, postoperative morphine consumption, incidence of postoperative nausea and vomiting (PONV), pruritus and urinary retention, ambulation, and satisfaction score were recorded. Patients were assessed at 3 h after surgery and twice daily on postoperative days (POD) 1 and 2.

RESULTS

Data of 54 patients were analyzed. Compared to the TAP group (n = 27), pain score on coughing was significantly lower in the CWI group (n = 27) on POD1 and POD2 (P < 0.05). Pain score on coughing at 3 h after surgery, pain score at rest at all assessed time points, morphine consumption, incidence of PONV, pruritus and urinary retention, ambulation, and satisfaction score were not different between the two groups.

CONCLUSION

CWI reduced pain on coughing after the day of surgery compared with single-injection TAP block when performed as part of multimodal analgesia in patients undergoing gynecologic laparotomy.