Ultrasound-guided erector spinae plane block for postoperative analgesia in laparoscopic liver resection: A prospective, randomised controlled, patient and observer-blinded study

Perioperative pain management with regional analgesia techniques for visceral cancer surgery: A systematic review and meta-analysis

STUDY OBJECTIVE

Regional analgesia following visceral cancer surgery might provide an advantage but evidence for best treatment options related to risk-benefit is unclear.

DESIGN

Systematic review of randomized controlled trials (RCT) with meta-analysis and GRADE assessment.

SETTING

Postoperative pain treatment.

PATIENTS

Adult patients undergoing visceral cancer surgery.

INTERVENTIONS

Any kind of peripheral (PRA) or epidural analgesia (EA) with/without systemic analgesia (SA) was compared to SA with or without placebo treatment or any other regional anaesthetic techniques.

MEASUREMENTS

Primary outcome measures were postoperative acute pain intensity at rest and during activity 24 h after surgery, the number of patients with block-related adverse events and postoperative paralytic ileus.

MAIN RESULTS

59 RCTs (4345 participants) were included. EA may reduce pain intensity at rest (mean difference (MD) -1.05; 95% confidence interval (CI): -1.35 to -0.75, low certainty evidence) and during activity 24 h after surgery (MD -1.83; 95% CI: -2.34 to -1.33, very low certainty evidence). PRA likely results in little difference in pain intensity at rest (MD -0.75; 95% CI: -1.20 to -0.31, moderate certainty evidence) and pain during activity (MD -0.93; 95% CI: -1.34 to -0.53, moderate certainty evidence) 24 h after surgery compared to SA. There may be no difference in block-related adverse events (very low certainty evidence) and development of paralytic ileus (very low certainty of evidence) between EA, respectively PRA and SA.

CONCLUSIONS

Following visceral cancer surgery EA may reduce pain intensity. In contrast, PRA had only limited effects on pain intensity at rest and during activity. However, we are uncertain regarding the effect of both techniques on block-related adverse events and paralytic ileus. Further research is required focusing on regional analgesia techniques especially following laparoscopic visceral cancer surgery.

Analgesic effects of ultrasound-guided preoperative posterior Quadratus Lumborum block in laparoscopic hepatectomy: A prospective double-blinded randomized controlled trial

STUDY OBJECTIVE

To determine if single-injection bilateral posterior quadratus lumborum block (QLB) with ropivacaine would improve postoperative analgesia in the first 24 h after laparoscopic hepatectomy, compared with 0.9% saline.

DESIGN

Prospective, double blinded, randomized controlled trial.

SETTING

A single tertiary care center from November 2021 and January 2023.

PATIENTS

A total of 94 patients scheduled to undergo laparoscopic hepatectomy due to hepatocellular carcinoma.

INTERVENTIONS

Ninety-four patients were randomized into a QLB group (receiving 20 mL of 0.375% ropivacaine on each side, 150 mg in total) or a control group (receiving 20 mL of 0.9% saline on each side).

MEASUREMENTS

The primary outcome was the cumulative opioid consumption during the initial 24-h post-surgery. Secondary outcomes included pain scores and intraoperative and recovery parameters.

MAIN RESULTS

The mean cumulative opioid consumption during the initial 24-h post-surgery was 30.8 ± 22.4 mg in the QLB group (n = 46) and 34.0 ± 19.4 mg in the control group (n = 46, mean differences: -3.3 mg, 95% confidence interval, -11.9 to 5.4, p = 0.457). The mean resting pain score at 1 h post-surgery was significantly lower in the QLB group than in the control group (5 [4-6.25] vs. 7 [4.75-8], p = 0.035). No significant intergroup differences were observed in the resting or coughing pain scores at other time points or in other secondary outcomes.

CONCLUSIONS

Preoperative bilateral posterior QLB did not reduce cumulative opioid consumption during the first 24 h after laparoscopic hepatectomy.

Effects of erector spinae plane block on opioid consumption in patients undergoing hand-assisted laparoscopic donor nephrectomy: a randomized controlled trial

BACKGROUND

The erector spinae plane block is a relatively new regional anesthesia technique that is expected to provide some benefits for postoperative analgesia. This study investigated the effects of erector spinae plane block on postoperative opioid consumption in kidney donors undergoing hand-assisted laparoscopic donor nephrectomy for renal transplantation.

METHODS

Fifty-two donors scheduled for elective hand-assisted laparoscopic donor nephrectomy were randomly divided into the block (25 donors) and control (27 donors) groups. Donors in the block group received 30 mL of 0.25% bupivacaine under ultrasound guidance, whereas the control group received no block treatment. The primary outcome measure was the amount of fentanyl administered via patient-controlled analgesia at 24 h. Secondary outcomes included the duration of stay, opioid consumption in the post-anesthesia care unit, and pain scores during the recording hours.

RESULTS

No significant differences were observed between the groups regarding total opioid consumption converted to intravenous morphine equivalent administered via patient-controlled analgesia (33.3±21.4 mg vs. 37.5±18.5 mg; P=0.27) and in the postanesthesia care unit (1.5±0.9 mg vs. 1.4±0.8 mg; P=0.55). The duration of stay in the postanesthesia care unit (86.3±32.6 min vs. 85.7±33.6 min; P=0.87) was similar between the groups. There was no significant difference between the groups in the postoperative donor-reported NRS pain scores (P>0.05 for all the time points).

CONCLUSIONS

Preoperative erector spinae plane block is not an effective strategy for reducing postoperative pain or opioid consumption in patients undergoing hand-assisted laparoscopic donor nephrectomy. Different block combinations are needed for optimal pain management in hand-assisted laparoscopic donor nephrectomy.

Erector spinae plane block for postoperative pain

BACKGROUND

Acute and chronic postoperative pain are important healthcare problems, which can be treated with a combination of opioids and regional anaesthesia. The erector spinae plane block (ESPB) is a new regional anaesthesia technique, which might be able to reduce opioid consumption and related side effects.

OBJECTIVES

To compare the analgesic effects and side effect profile of ESPB against no block, placebo block or other regional anaesthetic techniques.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and Web of Science on 4 January 2021 and updated the search on 3 January 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs) investigating adults undergoing surgery with general anaesthesia were included. We included ESPB in comparison with no block, placebo blocks or other regional anaesthesia techniques irrespective of language, publication year, publication status or technique of regional anaesthesia used (ultrasound, landmarks or peripheral nerve stimulator). Quasi-RCTs, cluster-RCTs, cross-over trials and studies investigating co-interventions in either arm were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all trials for inclusion and exclusion criteria, and risk of bias (RoB), and extracted data. We assessed risk of bias using the Cochrane RoB 2 tool, and we used GRADE to rate the certainty of evidence for the primary outcomes. The primary outcomes were postoperative pain at rest at 24 hours and block-related adverse events. Secondary outcomes were postoperative pain at rest (2, 48 hours) and during activity (2, 24 and 48 hours after surgery), chronic pain after three and six months, as well as cumulative oral morphine requirements at 2, 24 and 48 hours after surgery and rates of opioid-related side effects.

MAIN RESULTS

We identified 69 RCTs in the first search and included these in the systematic review. We included 64 RCTs (3973 participants) in the meta-analysis. The outcome postoperative pain was reported in 38 out of 64 studies; block-related adverse events were reported in 40 out of 64 studies. We assessed RoB as low in 44 (56%), some concerns in 24 (31%) and high in 10 (13%) of the study results. Overall, 57 studies reported one or both primary outcomes. Only one study reported results on chronic pain after surgery. In the updated literature search on 3 January 2022 we found 37 new studies and categorised these as awaiting classification. ESPB compared to no block There is probably a slight but not clinically relevant reduction in pain intensity at rest 24 hours after surgery in patients treated with ESPB compared to no block (visual analogue scale (VAS), 0 to 10 points) (mean difference (MD) -0.77 points, 95% confidence interval (CI) -1.08 to -0.46; 17 trials, 958 participants; moderate-certainty evidence). There may be no difference in block-related adverse events between the groups treated with ESPB and those receiving no block (no events in 18 trials reported, 1045 participants, low-certainty evidence). ESPB compared to placebo block ESPB probably has no effect on postoperative pain intensity at rest 24 hours after surgery compared to placebo block (MD -0.14 points, 95% CI -0.29 to 0.00; 8 trials, 499 participants; moderate-certainty evidence). There may be no difference in block-related adverse events between ESPB and placebo blocks (no events in 10 trials reported; 592 participants; low-certainty evidence). ESPB compared to other regional anaesthetic techniques Paravertebral block (PVB) ESPB may not have any additional effect on postoperative pain intensity at rest 24 hours after surgery compared to PVB (MD 0.23 points, 95% CI -0.06 to 0.52; 7 trials, 478 participants; low-certainty evidence). There is probably no difference in block-related adverse events (risk ratio (RR) 0.27, 95% CI 0.08 to 0.95; 7 trials, 522 participants; moderate-certainty evidence). Transversus abdominis plane block (TAPB) ESPB may not have any additional effect on postoperative pain intensity at rest 24 hours after surgery compared to TAPB (MD -0.16 points, 95% CI -0.46 to 0.14; 3 trials, 160 participants; low-certainty evidence). There may be no difference in block-related adverse events (RR 1.00, 95% CI 0.21 to 4.83; 4 trials, 202 participants; low-certainty evidence). Serratus anterior plane block (SAPB) The effect on postoperative pain could not be assessed because no studies reported this outcome. There may be no difference in block-related adverse events (RR 1.00, 95% CI 0.06 to 15.59; 2 trials, 110 participants; low-certainty evidence). Pectoralis plane block (PECSB) ESPB may not have any additional effect on postoperative pain intensity at rest 24 hours after surgery compared to PECSB (MD 0.24 points, 95% CI -0.11 to 0.58; 2 trials, 98 participants; low-certainty evidence). The effect on block-related adverse events could not be assessed. Quadratus lumborum block (QLB) Only one study reported on each of the primary outcomes. Intercostal nerve block (ICNB) ESPB may not have any additional effect on postoperative pain intensity at rest 24 hours after surgery compared to ICNB, but this is uncertain (MD -0.33 points, 95% CI -3.02 to 2.35; 2 trials, 131 participants; very low-certainty evidence). There may be no difference in block-related adverse events, but this is uncertain (RR 0.09, 95% CI 0.04 to 2.28; 3 trials, 181 participants; very low-certainty evidence). Epidural analgesia (EA) We are uncertain whether ESPB has an effect on postoperative pain intensity at rest 24 hours after surgery compared to EA (MD 1.20 points, 95% CI -2.52 to 4.93; 2 trials, 81 participants; very low-certainty evidence). A risk ratio for block-related adverse events was not estimable because only one study reported this outcome.

AUTHORS' CONCLUSIONS

ESPB in addition to standard care probably does not improve postoperative pain intensity 24 hours after surgery compared to no block. The number of block-related adverse events following ESPB was low. Further research is required to study the possibility of extending the duration of analgesia. We identified 37 new studies in the updated search and there are three ongoing studies, suggesting possible changes to the effect estimates and the certainty of the evidence in the future.

Efficacy of ultrasound-guided erector spinae plane block on analgesia and quality of recovery after minimally invasive direct coronary artery bypass surgery: protocol for a randomized controlled trial

BACKGROUND

Minimally invasive direct coronary artery bypass (MIDCAB) surgery offers an effective option for coronary artery disease (CAD) patients with the avoidance of median sternotomy and fast postoperative recovery. However, MIDCAB is still associated with significant postoperative pain which may lead to delayed recovery. The erector spinae plane block (ESPB) is a superficial fascial plane block. There have not been randomized controlled trials evaluating the effects of ESPB on analgesia and patient recovery following MIDCAB surgery. We therefore designed a double-blind prospective randomized placebo-controlled trial, aiming to prove the hypothesis that ESPB reduces postoperative pain scores in patients undergoing MIDCAB surgery.

METHODS

The study protocol has been reviewed and approved by the Ethical Review Committee of Peking University People's Hospital. Sixty adult patients of either sex scheduled for MIDCAB surgery under general anesthesia (GA) will be included. Patients will be randomly allocated to receive either a preoperative single-shot ESPB with 30 mL of ropivacaine 0.5% (ESPB group) or normal saline 0.9% (control group). The primary outcomes are the difference between the two groups in numeric rating scale (NRS) scores at rest at different time points (6, 12, 18, 24, 48 h) after surgery. The secondary outcomes include NRS scores on deep inspiration within 48 h, postoperative hydromorphone consumption, and quality of patient recovery at 24 h and 48 h, using the Quality of Recovery-15 (QoR-15) scale. The other outcomes include intraoperative fentanyl requirements, the need for additional postoperative rescue analgesics, time to tracheal extubation and chest tube removal after surgery, incidence of postoperative nausea and vomiting (PONV) and postoperative cognitive dysfunction (POCD), intensive care unit (ICU) length of stay (LOS), hospital discharge time, and 30-day mortality. Adverse events will be also evaluated.

DISCUSSION

This is a novel randomized controlled study evaluating a preoperative ultrasound-guided single-shot unilateral ESPB on analgesia and quality of patient recovery in MIDCAB surgery. The results of this study will characterize the degree of acute postoperative pain and clinical outcomes following MIDCAB. Our study may help optimizing analgesia regimen selection and improving patient comfort in this specific population.

TRIAL REGISTRATION

The study was prospectively registered with the Chinese Clinical Trial Registry (trial identifier: ChiCTR2100052810). Date of registration: November 5, 2021.

Analgesic efficacy of an opioid-free postoperative pain management strategy versus a conventional opioid-based strategy following open major hepatectomy: an open-label, randomised, controlled, non-inferiority trial

Background

Convincing clinical evidence regarding completely opioid-free postoperative pain management using erector spinae plane block (ESPB) in patients undergoing open major hepatectomy (OMH) is lacking. Herein, we aimed to compare the postoperative analgesic efficacy of the visualised continuous opioid-free ESPB (VC-ESPB) and conventional intravenous opioid-based postoperative pain management in hepatocellular carcinoma (HCC) patients undergoing OMH.

Methods

This open-label, randomised, controlled, non-inferiority trial enrolled patients with HCC undergone open major hepatectomy in Fujian Provincial Hospital and compared the postoperative analgesic efficacy of VC-ESPB (VC-ESPB group) and conventional intravenous opioid-based pain management regimen (conventional group). Patients were randomly assigned (1:1) to VC-ESPB group and conventional group. Patients were not masked to treatment allocation. The VC-ESPB group was treated with intermittent injections of 0.25% ropivacaine (bilateral, 30 mL each side) given every 12 h through catheters placed in the space of erector spinae and an opioid-free intravenous pump (10-mg tropisetron diluted to 100 mL with 0.9% normal saline [NS]) for postoperative pain management. The conventional group did not receive ESPB and was treated with a conventional intravenous opioid-based pump (2.5-μg/kg sufentanil and 10-mg tropisetron diluted to 100 mL with 0.9% NS). Patients in the VC-ESPB group underwent magnetic resonance imaging (MRI) to identify local anaesthetic diffusion after ESPB was performed under ultrasound guidance. The primary outcome was postoperative analgesic efficacy, which was indicated by the cumulative area under the curve (AUC) of the pain visual analogue scale scores (range, 0-10; a higher score indicates more pain) obtained at rest and at movement until 48 h postoperatively after leaving the post-anaesthesia care unit (PACU). Herein, an AUC of 26.5 was set as the noninferiority margin, which needed to be satisfied for both cumulative AUCPACU-48 h at rest and cumulative AUCPACU-48 h at movement. Per protocol participants were included in primary and safety analyses. This trial was registered with ChiCTR.org.cn (ChiCTR1900026583).

Findings

Between October 30, 2019, and May 1, 2023, 106 patients were enrolled and randomly assigned to the VC-ESPB group (n = 53) and the conventional group (n = 53). After the dropout (n = 5), a total of 101 patients (VC-ESPB group, n = 50; conventional group, n = 51) were analysed. Both the level of cumulative AUCPACU-48 h (at rest: 160.08 ± 38.00 vs. 164.94 ± 31.00; difference [90% CI], -4.861 [-16.308, 6.585]) and cumulative AUCPACU-48 h (at movement: 209.64 ± 28.98 vs. 212.59 ± 33.11; difference [90% CI], -2.948 [-13.236, 7.339]) were similar between the VC-ESPB and control groups within the first postoperative 48 h. The upper limit of the 90% CIs for the difference in cumulative ACUPACU-48 h at rest and at movement did not reach the upper inferiority margin (26.5). During the first postoperative 48 h, the rate of nonsteroidal anti-inflammatory drug rescue analgesia was similar between the VC-ESPB group and conventional group (n = 16, 32.0% vs. n = 11, 21.6%; P = 0.236). Treatment-related death was not observed in the VC-ESPB group (n = 0, 0%) and conventional group (n = 0, 0%). In VC-ESPB group, local site paralysis (n = 1, 2.0%) was observed in one patient and rash (n = 1, 2.0%) was observed in another patient. One patient in the conventional group was observed with rash preoperatively (n = 1, 2.0%). The VC-ESPB group had significantly lower rates of postoperative nausea (n = 2, 4.0%, vs. n = 9, 17.6%, P = 0.028), vomiting (n = 1, 2.0% vs. n = 8, 15.7%, P = 0.031) and lower incidence of major complications (n = 4, 8.0% vs. n = 6, 11.8%; P = 0.033).

Interpretation

This study demonstrates the noninferiority of VC-ESPB when compared with the conventional opioid-based approach for postoperative pain management after OMH, suggesting that it is feasible to achieve opioid-free postoperative pain management for OMH.

Funding

The Joint Funds for the Innovation of Science and Technology, Fujian Province, China; the Youth Scientific Research Project of Fujian Provincial Health Commission; the Fujian Research and Training Grants for Young and Middle-aged Leaders in Healthcare; and the Key Clinical Specialty Discipline Construction Program of Fujian, China.

Postoperative analgesia efficacy of erector spinae plane block in adult abdominal surgery: A systematic review and meta-analysis of randomized trials

Objectives

Erector spinae plane block (ESPB) has been used for many thoracic and abdominal surgeries. However, evidence of its analgesic efficacy following abdominal surgery, compared with that of thoracic analgesia, is insufficient. Our study explored the analgesic effect of ESPB after abdominal surgery.

Methods

We searched PubMed, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov. Primary outcomes were pain scores at 6, 12 and 24 h and 24-h opioid consumption. Secondary outcomes included time to first rescue analgesia, length of hospital stay, and incidence of postoperative nausea and vomiting (PONV). We calculated standardized mean differences (SMDs) with 95% confidence intervals (CIs) for primary outcomes and mean differences (MDs) and risk ratios (RRs) with 95% CIs for secondary outcomes.

Results

We systematically included 1,502 cases in 24 trials. Compared with placebo, ESPB significantly reduced pain scores at 6 h (SMD -1.25; 95% CI -1.79 to -0.71), 12 h (SMD -0.85; 95% CI -1.33 to -0.37) and 24 h (SMD -0.84; 95% CI -1.30 to -0.37) and 24-h opioid consumption (SMD -0.62; 95% CI -1.19 to -0.06) post-surgery. ESPB prolonged the time to first rescue analgesia and decreased the incidence of PONV. Compared with transversus abdominal plane block (TAPB), ESPB significantly reduced pain scores at 6, 12, and 24 h and 24-h opioid consumption and prolonged the time to first rescue analgesia postsurgically. Furthermore, subgroup analysis showed that ESPB significantly reduced pain scores at various time points and opioid consumption within 24 h after laparoscopic cholecystectomy, percutaneous nephrolithotomy and bariatric surgery.

Conclusion

Compared with placebo, ESPB improves the postoperative analgesic efficacy after abdominal surgery. Furthermore, our meta-analysis confirmed that ESPB provides more beneficial analgesic efficacy than TAPB.

Systematic review registration

[https://www.crd.york.ac.uk/PROSPEROFILES/301491_STRATEGY_20220104.pdf], identifier [CRD42022301491].

Pain Management After Open Liver Resection: Epidural Analgesia Versus Ultrasound-Guided Erector Spinae Plane Block

Background: Multimodal analgesia techniques, including regional analgesia, have been shown to provide effective analgesia and minimize opioid consumption after liver resection surgery. While thoracic epidural analgesia (TEA) is considered the gold standard, its role in the current era of enhanced recovery after surgery (ERAS) has been questioned. Erector spinae plane blocks (ESPBs) have the potential to provide effective postoperative analgesia without the risks associated with epidural analgesia. The primary aim of this quality improvement project was to evaluate the analgesic efficacy of ultrasound-guided ESPB in comparison with TEA in patients undergoing open liver resection.

Methods: Fifty patients who underwent open liver resection and received TEA (n=25) or ESPB (n=25) as part of an ERAS pathway were retrospectively identified. The primary outcome measure was cumulative postoperative opioid consumption at 24 hours. Secondary outcomes included opioid consumption, pain scores, the incidence of nausea and vomiting requiring antiemetics, lower extremity muscle weakness, and occurrence of hypotension requiring treatment on arrival to the post-anesthesia care unit and at 2, 6, 12, 24 hours, and daily through postoperative day 7. 

Results: Opioid requirements were significantly lower in the TEA group compared to the ESPB group. Postoperative pain scores at rest and with deep inspiration were significantly lower in the TEA group through postoperative day 5. There were no differences in other outcome measures.

Conclusions: These findings suggest that compared with ESPB, TEA provides superior pain relief after open liver resection.

Erector Spinae Plane Block in Abdominal Surgery: A Meta-Analysis

Background

Abdominal surgery is one of the most definitive and mainstay treatment options for abdominal pathologies in clinical practice. Acute postoperative pain is a major challenge in the postoperative period. Although opioids are commonly used for analgesia after major abdominal surgeries, they can lead to side effects, such as nausea and vomiting, constipation, pruritus, and life-threatening respiratory depression. Regional anesthetic techniques are commonly used to prevent or minimize these side effects. The objective of this meta-analysis is to assess the effectiveness of erector spinae plane block (ESPB) and standard medical (no block) pain management after major abdominal surgeries.

Methods

We searched for articles reporting the results of randomized controlled trials on ESPB and no block in pain control published before May 2021.

Results

The systematic search initially yielded 56 publications, 49 articles were excluded, and seven randomized clinical trials were included and analyzed. We extracted the data on postoperative opioid consumption, the efficacy of pain relief, time to the first opioid demand, and the rate of postoperative complications in the ESPB group and no block group.

Conclusions

Opioid requirement and time to first analgesic request were significantly reduced in the ultrasound-guided ESPB group, but pain scores, nausea, and vomiting did not differ significantly after pooling the results of the block and no block studies. There were no reports on serious complications related to ESPB.

Comparison of Analgesic Efficacy of Erector Spinae Plane Block and Posterior Quadratus Lumborum Block in Laparoscopic Liver Resection: A Randomized Controlled Trial

Purpose

Ultrasound-guided fascial plane blocks, including the erector spinae plane (ESP) and quadratus lumborum (QL) blocks, provide effective postoperative abdominal analgesia. However, there is limited evidence on the analgesic efficacy of ESP and QL blocks after liver surgery. Therefore, we aimed to compare the cumulative opioid consumption between the ESP and QL blocks in patients with hepatocellular carcinoma undergoing laparoscopic liver resection.

Patients and Methods

Eighty-eight patients scheduled to undergo laparoscopic liver resection were randomized to receive bilateral single injection of ESP block at T8 (ESP group) or bilateral single injection of posterior QL block (QL group; 20 mL of 0.375% ropivacaine for each side, ie, total 150 mg of ropivacaine), in addition to intravenous (IV) fentanyl patient-controlled analgesia and multimodal analgesia. The primary outcome was cumulative opioid consumption over the first 24 h, expressed as IV morphine equivalents. Secondary outcomes included serial plasma ropivacaine concentrations, pain scores, time to first flatus, and Quality of Recovery-15 scores.

Results

Eighty-five patients were analyzed (ESP group, n = 42; QL group, n = 43). Cumulative 24-h opioid consumption was similar between the ESP and QL groups (41.4 ± 22.6 mg vs 44.2 ± 20.0 mg, mean difference (QL-ESP), 2.8 mg, 95% confidence interval, −6.4 to 12 mg, p > 0.99). There were no significant differences in resting pain scores at 24, 48 and 72 h postoperatively or recovery outcomes. The peak plasma ropivacaine concentration 30 min after injection was significantly higher in the ESP group (1.5 ± 0.3 µg/mL) than in the QL group (1.3 ± 0.5 µg/mL, p = 0.035); however, both were lower than the arterial threshold value of systemic toxicity (4.3 µg/mL).

Conclusion

ESP and QL blocks provided similar postoperative analgesia in patients undergoing laparoscopic liver resection.