Efficacy of regional anesthesia techniques for postoperative analgesia in patients undergoing major oncologic breast surgeries: a systematic review and network meta-analysis of randomized controlled trials

Anatomical assessments of injectate spread stratified by the volume of the intertransverse process block at the T2 level

BACKGROUND

This cadaveric study aimed to analyze injectate spread to target nerves during a single-injection, ultrasound-guided intertransverse process block.

METHODS

An ultrasound-guided intertransverse process block with three different injectate volumes was administered to 12 cadavers. Each hemithorax was subjected to computer-generated random allocation of 10, 15, or 20 mL ultrasound-guided, single-injection intertransverse process block at the T2 vertebral level. Latex dye solution was injected into each hemithorax in accordance with the allocated volume. The presence of dye at the nerve root in the sympathetic chain and intercostal nerves at various injection levels was examined via dissection.

RESULTS

Injectate spread into the dorsal rami was observed in seven of eight (87.5%), seven of eight (87.5%), and all eight (100%) of the 10, 15, and 20 mL specimens, respectively. In all 20 mL specimens, consistent staining of the dorsal rami, spinal nerve, and dorsal root ganglion was observed.

CONCLUSIONS

An injectate volume of 20 mL was required for consistent staining of the dorsal rami, spinal nerve, and dorsal root ganglion in an intertransverse process block. Although an augmented injectate volume was associated with an increased likelihood of target nerve staining, consistent staining of the sympathetic ganglion, rami communicans, and ventral ramus was not observed, even at a volume of 20 mL. The current study presents initial findings suggesting that as opposed to a sympathetic ganglion block, a 20 mL intertransverse process block may act as a feasible substitute for dorsal root ganglion, spinal nerve, and medial branch blocks within a clinical context.

Effect of Surgeon-Performed Thoracic Paravertebral Block on Postoperative Pain in Adolescent Idiopathic Scoliosis Surgery: A Prospective Randomized Controlled Trial

Posterior spinal fusion for adolescent idiopathic scoliosis (AIS) causes severe postoperative pain. Thoracic paravertebral block (PVB) provides excellent analgesia during various surgeries. We examined the effects of PVB on postoperative analgesia in children undergoing AIS surgery. In this study, 32 children scheduled for AIS surgery were randomly assigned to receive either PVB (PVB group) or no block (control group). The PVB group underwent surgeon-performed PVB with 0.5 mL/kg of adrenalized 0.2% ropivacaine on each side. The primary outcome was the pain score at rest at 6 h postoperatively. Secondary outcomes included pain scores both at rest and during movement and analgesic use for 48 h postoperatively. The postoperative resting pain scores at 6 h were comparable between the control and PVB groups (5.2 ± 2.0 and 5.1 ± 1.8, respectively), with no significant differences. However, at 1 h postoperatively, the control group showed significantly higher resting and mean moving pain scores than the PVB group (p < 0.05). The pain scores at other time points and analgesic use were comparable between the groups. Initial benefits of surgeon-performed bilateral PVB were observed but diminished at 6 h postoperatively. Future research using various anesthetics is needed to extend the effects of PVB.

Ultrasound-guided mid point-transverse process to pleura block versus thoracic paravertebral block in pediatric open-heart surgery: A randomized controlled non-inferiority study

STUDY OBJECTIVE

The mid point-transverse process to pleura block (MTPB) is a new variant of thoracic paravertebral block (TPVB). This study aimed to compare TPVB and MTPB with respect to intraoperative attenuation of the hemodynamic stress response to surgery and postoperative analgesia in pediatric open heart surgery with midline sternotomy.

DESIGN

A single-center, randomized, controlled, double-blind, non-inferiority study.

SETTING

Tertiary care children's university hospital.

PATIENTS

We recruited 83 children aged 2-12 years of both sexes with American Society of Anesthesiologists (ASA) physical status class II who were scheduled for elective open cardiac surgeries with midline sternotomy for the repair of simple noncyanotic congenital heart defects.

INTERVENTIONS

Eligible participants were randomized into either the TPVB or MTPB groups at a ratio of 1:1. In the TPVB group, patients were bilaterally injected with 0.4 ml/kg of 0.25% bupivacaine in the paravertebral space at T4 and T5. In the MTPB group, patients were bilaterally injected with 0.4 ml/kg of 0.25% bupivacaine mid-transverse process and pleura just posterior to superior costotransverse ligament at the level of T4 and T5.

MEASUREMENTS

The primary outcome was the hemodynamic responses to sternotomy incision, including heart rate (HR) and invasive mean arterial pressure (MAP), recorded before and after the induction of anesthesia, after skin incision, after sternotomy, 15 min after cardiopulmonary bypass (CPB), and after the closure of the sternum. The secondary outcomes were time needed to perform the bilateral block, intraoperative fentanyl consumption, postoperative fentanyl consumption, modified objective pain score (MOPS) measured at 1, 2, 6, 12, 18, and 24 h after extubation, extubation time, intensive care unit (ICU) discharge time, and the incidence of non-surgical complications (postoperative pruritus, postoperative vomiting, pneumothorax, hematoma or local anesthetic toxicity).

MAIN RESULTS

There were no significant differences in HR and MAP in the TPVB group compared with the MTPB group at the following time points: baseline, after induction, after skin incision, after sternotomy, 15 min after CPB, and after sternal closure. Intergroup comparisons of HR and MAP did not reveal significant differences between the groups. The median (IQR) time needed to perform bilateral MTPB (7[6-8] min) was significantly (p < 0.001) shorter than that of TPVB (12[10-13] min). Intraoperative fentanyl consumption and fentanyl consumption in the first postoperative 24 h after extubation were similar in the TPVB and MTPB groups (4[2-4] vs 4[2-4] and 4.66 ± 0.649 vs 4.88 ± 1.082 μg/kg), respectively. Extubation time and ICU discharge time were comparable in the TPVB and MTPB groups (2[1-3] vs 2[1-3] h and 21.2 ± 2.5 vs 20.8 ± 2.6 h), respectively. Measurements of MOPS pain scores at 1, 2, 6, 12, 18, and 24 h after extubation were similar in both groups. The incidence of nonsurgical complications was similar in both groups.

CONCLUSIONS

MTPB is non-inferior to TPVB in attenuating the intraoperative hemodynamic stress response to noxious surgical stimuli and in reducing perioperative opioid consumption, extubation time, and ICU discharge time. Moreover, MTPB is technically easier than TPVB and requires less time to perform. Clinical trial registration number The clinical trial registration was prospectively performed at the Pan African Clinical Trials Registry (PACTR202204901612169, approval date 01/04/2022, URL https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=22602).

Comparison of injectate spread and nerve coverage between single-injection intertransverse process block and paravertebral block at the T2 level: a cadaveric study

BACKGROUND

We compared the spread of an injectate into the thoracic sympathetic chain resulting from a single-injection intertransverse process (ITP) block with that of a single-injection PV block at the T2 level.

METHODS

Sixteen soft-embalmed cadavers were used. The right hemithorax was randomly allocated to receive either an ultrasound-guided single-injection ITP block or ultrasound-guided single-injection PV block at the T2 vertebral level, with the opposite block administered to the other side. Approximately 10 mL of latex dye solution was injected into each hemithorax using a random allocation technique. The presence of dye at the nerve root in the sympathetic chain and intercostal nerves at the injection and additional levels was examined by dissection.

RESULTS

The injectate spread into the T2 sympathetic ganglion on both ITP (11/16, 68.8%) and PV (16/16, 100%) blocks. The ITP block demonstrated greater uniformity of dye staining in both the dorsal rami and dorsal root ganglion, which contrasts with the less consistent staining outcomes of the PV block in these regions.

CONCLUSIONS

At the T2 level, we observed a lower efficacy of the ITP block for analgesic coverage of the sympathetic nerve. This suggested a potential preference by clinicians for the application of the T2 PV block over the ITP block, specifically for the management of sympathetically maintained pain in the upper extremities. In addition, our findings may hint at the potential advantages of the ITP block in specific clinical contexts where targeted nerve involvement, such as the medial branch block or dorsal root ganglion block, is sought.

Usefulness of ultrasound-guided serratus-anterior block in prevention of postoperative pain after breast surgery. A cohort study

OBJECTIVE

To evaluate superficial serratus anterior plane block's efficacy and side effects in preventing postoperative pain after breast cancer surgery.

METHODOLOGY

A prospective cohort study was conducted on 195 adult patients undergoing breast oncological surgery under general anesthesia (Group G, n = 96) or combined general anesthesia with superficial serratus anterior plane block (Group L, n = 99). Validated preoperative data, which are predictors of chronic postoperative pain of patients, were recorded (type of surgery, age, pain in the area of the intervention and the other regions; anesthetic-surgical data, analgesic doses used, duration of surgery; pain intensity (EVN scale) at immediate postoperative period, 24 h, seven days and one month after the surgery, and complications.

RESULTS

Pain intensity, measured by the EVN scale, had a mean of 1.02 +/- 1.656 in the Postoperative Unit; 1.20 +/- 1.448 at 24 h; 0.76 +/- 1208 seven days; and 0.34 +/- 0.757 one month after surgery. Patients were operated under general anesthesia (n = 96) or general anesthesia combined with the interfascial block (n = 99). Significant differences (p < 0.05) were found in age, height, and VAS scale in PACU. Ten complications were recorded, six in Group L and four in Group G. There were no differences between groups in complications.

CONCLUSIONS

Superficial serratus anterior plane blocks are effective and safe in pain control in the immediate postoperative period for breast cancer surgery as a part of the multimodal approach. No significant differences were found one week and one month after surgery.

Ultrasound-Guided Regional Anesthesia Using a Mixture of Dexamethasone, Dexmedetomidine, and 0.2% Levobupivacaine for Bilateral Breast Cancer Surgery Under a Spontaneous Breathing Opioid-Free Anesthesia: A Case Report

Breast cancer is unfortunately the most common cancer in women, although survival rates have greatly increased in recent years. Breast surgery can be very aggressive and therefore highly painful, leading to high rates of acute postsurgical pain and chronic pain. In addition to general anesthesia (GA), ultrasound-guided regional anesthesia (RA) is sometimes performed to help reduce acute postoperative pain and consumption of opioids. Although effective, the main limitation of fascial plane blocks is that they require high volumes of local anesthetics, carrying the risk of local anesthetic systemic toxicity. In this article, we present the case of a 41-year-old woman, who refused GA and was successfully operated on for bilateral breast cancer, under a spontaneous breathing opioid-free sedation and ultrasound-guided RA, based on only 0.2% levobupivacaine with the addition of dexamethasone and dexmedetomidine as adjuvants. Despite this, postoperative analgesia lasted for more than 48 hours, and the patient did not require additional analgesia or opioids.

Novel Serratus Posterior Superior Intercostal Plane Block Provided Satisfactory Analgesia after Breast Cancer Surgery: Two Case Reports

The serratus posterior superior intercostal plane (SPSIP) block is a novel technique recently described for thoracic analgesia. This study presents two cases using this technique for postoperative pain after mastectomy with axillary lymph node dissection. The SPSIP block was administered to the patients in the preoperative period as part of multimodal analgesia, and postoperative pain was monitored using the numeric rating scale (NRS). In both patients, the NRS pain scores were below 3/10. SPSIP provided adequate postoperative analgesia in these cases without the need for any opioid agents. Thus, an SPSIP block can be a valuable treatment option for postoperative pain after breast surgery.

The effect of different nerve block strategies on the quality of post-operative recovery in breast cancer patients: A randomized controlled study

OBJECTIVE

To compare the effects of three types of ultrasound-guided nerve blocks on post-operative recovery quality in patients undergoing modified radical mastectomy for unilateral breast cancer.

METHODS

In this randomized double-blinded trial (chictr.org.cn, ChiCTR2200059428), 150 female patients were equally assigned to S group (serratus anterior plane block, SAPB) group, P group (paravertebral block, PVB) or ST group (serratus anterior combined with transverse thoracic muscle plane blocks, SA-TTMPB). The primary outcome was QoR-15 at five time points after surgery. Secondary outcomes were pain scores, time of first rescue analgesic and chronic pain incidence at 3 months.

RESULTS

The QoR-15 total score of S group at 24 h, 48 h, 72 h and 7 days post-surgery was significantly lower in groups P and ST, while there was no significant difference between groups P and ST (S vs. P vs. ST, 100.29 ± 6.20 vs. 108.51 ± 7.46 vs. 106.46 ± 6.95; 105.59 ± 6.18 vs. 113.06 ± 7.44 vs. 111.22 ± 6.56; 112.51 ± 6.32 vs. 119.88 ± 6.44 vs. 117.62 ± 6.09; 123.00 ± 5.78 vs. 128.86 ± 5.96 vs. 126.92 ± 5.72, p < 0.05). The dynamic and rest NRS scores at 6 and 12 h post-surgery were significantly higher in group S than in groups P and ST.

CONCLUSION

Serratus anterior plane block combined with transverse thoracic muscle plane block and paravertebral block both have better effects than serratus anterior plane block alone in improving patients' early post-operative recovery quality, and also have an advantage in improving early post-operative pain.

CLINICAL TRIAL REGISTRATION

chictr.org.cn (ChiCTR2200059428).

DATE OF REGISTRATION

29 April 2022.

SIGNIFICANCE

Serratus anterior combined with transverse thoracic muscle plane block may be a safer, easier, and equally effective nerve block strategy than paravertebral block in patients undergoing modified radical mastectomy for unilateral breast cancer.

Comparative efficacy and safety of non-neuraxial analgesic techniques for midline laparotomy: a systematic review and frequentist network meta-analysis of randomised controlled trials

BACKGROUND

Fascial plane blocks provide effective analgesia after midline laparotomy; however, the most efficacious technique has not been determined. We conducted a systematic review and network meta-analysis of randomised controlled trials to synthesise the evidence with respect to pain, opioid consumption, and adverse events.

METHODS

We searched Ovid MEDLINE, Embase, Cochrane Central, and Scopus databases for studies comparing commonly used non-neuraxial analgesic techniques for midline laparotomy in adult patients. The co-primary outcomes of the study were 24-h cumulative opioid consumption and 24-h resting pain score, reported as i.v. morphine equivalents and 11-point numerical rating scale, respectively. We performed a frequentist meta-analysis using a random-effects model and a cluster-rank analysis of the co-primary outcomes.

RESULTS

Of 6115 studies screened, 67 eligible studies were included (n=4410). Interventions with the greatest reduction in 24-h cumulative opioid consumption compared with placebo/no intervention were single-injection quadratus lumborum block (sQLB; mean difference [MD] -16.1 mg, 95% confidence interval [CI] -29.9 to -2.3, very low certainty), continuous transversus abdominis plane block (cTAP; MD -14.0 mg, 95% CI -21.6 to -6.4, low certainty), single-injection transversus abdominis plane block (sTAP; MD -13.7 mg, 95% CI -17.4 to -10.0, low certainty), and continuous rectus sheath block (cRSB; MD -13.2 mg, 95% CI -20.3 to -6.1, low certainty). Interventions with the greatest reduction in 24-h resting pain score were cRSB (MD -1.2, 95% CI -1.8 to -0.6, low certainty), cTAP (MD -1.0, 95% CI -1.7 to -0.2, low certainty), and continuous wound infusion (cWI; MD -0.7, 95% CI -1.1 to -0.4, low certainty). Clustered-rank analysis including the co-primary outcomes showed cRSB and cTAP blocks to be the most efficacious interventions.

CONCLUSIONS

Based on current evidence, continuous rectus sheath block and continuous transversus abdominis plane block were the most efficacious non-neuraxial techniques at reducing 24-h cumulative opioid consumption and 24-h resting pain scores after midline laparotomy (low certainty). Future studies should compare techniques for upper vs lower midline laparotomy and other non-midline abdominal incisions.

CLINICAL TRIAL REGISTRATION

PROSPERO Registration Number: CRD42021269044.

Evidence-Based Guideline on the Prevention and Management of Perioperative Pain for Breast Cancer Peoples in a Low-Resource Setting: A Systematic Review Article

Background

Breast surgery for breast cancer is associated with significant acute and persistent postoperative pain. Surgery is the primary type of treatment, but up to 60% of breast cancer patients experience persistent pain after surgery, and 40% of them develop acute postmastectomy pain syndrome. Preoperative stress, involvement of lymph nodes while dissecting, and the postoperative psychological state of the patients play vital roles in managing the postoperative pain of the patients. The objective of this study is to develop evidence-based guideline on the prevention and management of perioperative pain for breast cancer surgical patients.

Methods

An exhaustive literature search was made from PubMed, Cochrane Review, PubMed, Google Scholar, Hinari, and CINAHIL databases that are published from 2012 to 2022 by setting the inclusion and exclusion criteria. After data extraction, filtering was made based on the methodological quality, population data, interventions, and outcome of interest. Finally, one guideline, two meta-analyses, ten systematic reviews, 25 randomized clinical trials and ten observational studies are included in this review, and a conclusion was made based on their level of evidence and grade of recommendation.

Results

A total of 38 studies were considered in this evaluation. The development of this guideline was based on different studies performed on the diagnosis, risk stratification and risk reduction, prevention of postoperative pain, and treatments of postoperative pain.

Conclusion

The management of postoperative pain can be categorized as risk assessment, minimizing risk, early diagnosis, and treatment. Early diagnosis is the mainstay to identify and initiate treatment. The perioperative use of a nonpharmacological approach (including preoperative positive inspirational words and positive expectation) as an adjunct to the intraoperative regional anesthetic technique with general anesthesia with proper dosage of the standard pharmacological multimodal regimens is the first-line treatment. For postoperative analgesia, an extended form of intraoperative regional technique, nonpharmacologic technique, and NSAIDs can be used with the opioid-sparing anesthesia technique.

Basic analgesic use in randomised trials assessing local and regional analgesic interventions for mastectomy: a critical appraisal and clinical implications

Regional analgesia is a core component of an optimal multimodal analgesia technique. Several advanced regional analgesic techniques have been evaluated for mastectomy; however, the optimal choice remains unclear. Many randomised clinical trials (RCTs) evaluating various local/regional analgesic techniques do not include basic analgesics (i.e. paracetamol, non-steroidal anti-inflammatory drugs, cyclooxygenase-2 specific inhibitors, and dexamethasone) which precludes objective evaluation of their efficacy. The aim of this scoping review was to assess the use of basic analgesics in RCTs evaluating efficacy of local and regional analgesic techniques in patients undergoing mastectomy. PubMed was searched to identify relevant articles from January 1, 2010 to May 31, 2023. The key finding of this study is that almost 90% (n=82/92) of the RCTs evaluating local/regional analgesic techniques in patients undergoing mastectomy did not administer well accepted basic analgesics in the comparator groups. Consequently, the conclusions of the RCTs assessing local/regional analgesic techniques for mastectomy should be interpreted with caution. Also, clinical guidelines based on meta-analyses of these RCTs could be inadequate or inappropriate.

Impact of paravertebral block on perioperative neurocognitive disorder: a systematic review and meta-analysis of randomized controlled trials

Objective

To investigate whether paravertebral block reduces postoperative delirium (POD)/delayed neurocognitive recovery (DNR) in adults after major surgery with general anesthesia.

Methods

For this systematic review and meta-analysis, we searched online databases PubMed, EMBASE, CENTRAL, and Web of Science till March 19th, 2023 to examine studies which use paravertebral block (PVB) for perioperative neurocognitive disorder. Primary and secondary outcomes were identified for the incidence of perioperative neurocognitive disorder. We did not restrict the follow-up duration of the included studies. Statistical analysis was performed to calculate mean difference (MD), Odd ratios (OR) and CI between RCTs. The quality of the evidence was assessed with the Cochrane risk of bias tool. The registration number of the study in PROSPERO is CRD42023409502. PROSPERO is an international database of prospectively registered systematic reviews. Registration provides transparency in the review process and it helps counter publication bias.

Results

Total 1,225 patients from 9 RCTs were analyzed. The incidence of POD [Odds Ratio (OR) = 0.48, 95% CI 0.32, 0.72; p = 0.0004; I2 = 0%] and DNR [OR = 0.32, 95% CI 0.13, 0.80; p = 0.01; I2 = 0%] were significantly reduced in PVB group. The analysis showed no significant differences in postoperative MMSE scores [MD = 0.50, 95% CI -2.14, 3.15; p = 0.71; I2 = 98%]. Paravertebral block analgesia reduces pain scores and/or opioid use after surgery. Additionally, blood pressure was significantly lower in the PVB group, intraoperatively [MD = -15.50, 95% CI -20.71, -10.28; p < 0.001; I2 = 12%] and postoperatively [MD = -5.34, 95% CI -10.65, -0.03 p = 0.05; I2 = 36%]. Finally, PVB group had significantly shorter hospital stays [MD = -0.86, 95% CI -1.13, -0.59; p < 0.001; I2 = 0%].

Conclusion

Paravertebral block analgesia may prevent perioperative POD/DNR in patients undergoing major surgery. Further research with large sample sizes is required to confirm its effectiveness.

Research Progress on Serratus Anterior Plane Block in Breast Surgery: A Narrative Review

Breast surgery, especially radical mastectomy, is often accompanied by moderate to severe acute pain, which significantly reduces postoperative quality of life. Effective pain management can accelerate patient recovery. Serratus anterior plane block (SAPB) is a new type of fascial plane block technique, which can better target the nerve network innervating the chest wall and breast and provide good analgesia in the anterolateral chest wall. Current clinical research evidence indicates that SAPB has significant benefits in breast surgery. Further research avenues for this technology include optimal local anesthetic dosing strategy, the type of SAPB which is more suitable for breast surgery, comparison of SAPB and pectoral nerve block II (PECS II) in breast surgery, and high-quality randomized controlled study with outcomes of chronic pain or cancer prognosis.

The postoperative analgesic efficacy of different regional anesthesia techniques in breast cancer surgery: A network meta-analysis

Background

Regional anesthesia have been successfully performed for pain management in breast cancer surgery, but it is unclear which is the best regional anesthesia technique. The aim of the present network meta-analysis was to assess the analgesic efficacy and disadvantages of regional anesthesia techniques.

Methods

Multiple databases were searched for randomized controlled trials (RCTs). The association between regional anesthesia and analgesic efficacy was evaluated by Bayesian network meta-analysis.

Results

We included 100 RCTs and 6639 patients in this study. The network meta-analysis showed that paravertebral nerve block, pectoral nerve-2 block, serratus anterior plane block, erector spinae plane block, rhomboid intercostal block, and local anesthetic infusion were associated with significantly decreased postoperative pain scores, morphine consumption and incidence of postoperative nausea and vomiting compared with no block. Regarding the incidence of chronic pain, no significance was detected between the different regional anesthesia techniques. In the cumulative ranking curve analysis, the rank of the rhomboid intercostal block was the for postoperative care unit pain scores, postoperative 24-hour morphine consumption, and incidence of postoperative nausea and vomiting.

Conclusion

Regional anesthesia techniques including, paravertebral nerve block, pectoral nerve-2 block, serratus anterior plane block, erector spinae plane block, rhomboid intercostal block, and local anesthetic infusion, can effectively alleviate postoperative acute analgesia and reduce postoperative morphine consumption, but cannot reduce chronic pain after breast surgery. The rhomboid intercostal block might be the optimal technique for postoperative analgesia in breast cancer surgery, but the strength of the evidence was very low.

Systematic review registration

https://www.crd.york.ac.uk/prospero/(PROSPERO), identifier CRD 42020220763.

Apoptosis, Proliferation, and Autophagy Are Involved in Local Anesthetic-Induced Cytotoxicity of Human Breast Cancer Cells

Breast cancer accounts for almost one quarter of all female cancers worldwide, and more than 90% of those who are diagnosed with breast cancer undergo mastectomy or breast conservation surgery. Local anesthetics effectively inhibit the invasion of cancer cells at concentrations that are used in surgical procedures. The limited treatment options for triple-negative breast cancer (TNBC) demonstrate unmet clinical needs. In this study, four local anesthetics, lidocaine, levobupivacaine, bupivacaine, and ropivacaine, were applied to two breast tumor cell types, TNBC MDA-MB-231 cells and triple-positive breast cancer BT-474 cells. In addition to the induction of apoptosis and the suppression of the cellular proliferation rate, the four local anesthetics decreased the levels of reactive oxygen species and increased the autophagy elongation indicator in both cell types. Our combination index analysis with doxorubicin showed that ropivacaine had a synergistic effect on the two cell types, and lidocaine had a synergistic effect only in MDA-MB-231 cells; the others had no synergistic effects on doxorubicin. Lidocaine contributed significantly to the formation of autophagolysosomes in a dose-dependent manner in MDA-MB-231 cells but not in BT-474 cells. Our study demonstrated that the four local anesthetics can reduce tumor growth and proliferation and promote apoptosis and autophagy.

Ultrasound-Guided Erector Spinae Plane Block in Thoracolumbar Spinal Surgery: A Systematic Review and Meta-Analysis

Introduction

Neurosurgical spinal surgeries such as micro- discectomy and complex fusion surgeries remain the leading causes of disability-adjusted life-year. Major spinal surgeries often result in severe postprocedural pain due to massive dissection of the underlying tissues. While opioids offer effective pain control, they frequently lead to side effects, such as post-operative nausea and vomiting, pruritus, constipation, and respiratory depression. ESPB was successfully used in spinal surgery as a component of a multimodal analgesic regimen and it eliminated the requirements for opioids. The primary purpose of this systematic review and meta-analysis was to compare post-operative opioid consumption between ESPB and placebo.

Methods

To conduct this systematic review, we used the “Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)” guidelines. We conducted a search for relevant articles available in the following databases: Google Scholar, PubMed, and the Cochrane Library published up to March 2022.

Results

The total morphine consumption within 24 h after surgery was lower in the ESPB group, the mean difference (in mg of morphine) with 95% CI is −9.27 (−11.63, −6.91). The pain intensity (0–10) at rest measured 24 h after surgery was lower in the ESPB group, the MD with 95% CI is −0.47 (−0.77, −0.17). The pain intensity during movement measured 24 h after surgery was lower in the ESPB group, the MD with 95% CI is −0.73 (−1.00, −0.47). Post-operative nausea and vomiting were significantly lower in the ESPB group, the risk ratio with 95% CI is 0.32 (0.19, 0.53).

Conclusion

Ultrasound-guided ESPB was superior to placebo in reducing post-operative opioid consumption, pain intensity, post-operative nausea and vomiting, and prolonging the time to first rescue analgesia. There were no ESPB-related serious complications reported.

Anatomical classification and clinical application of thoracic paraspinal blocks

Various techniques for regional anesthesia and analgesia of the thorax are currently being used in clinical practice. A recent international consensus has anatomically classified paraspinal blocks in the thoracic spinal region into the following four types: paravertebral, retrolaminar, erector spinae plane, and intertransverse process blocks. These blocks have different anatomical targets; thus, the spreading patterns of the injectates differ and can consequently exhibit different neural blockade characteristics. The paravertebral block directly targets the paravertebral space just outside the neuraxial region and has an analgesic efficacy comparable to that of the epidural block; however, there are multiple potential risks associated with this technique. Retrolaminar and erector spinae plane blocks target the erector spinae plane on the vertebral lamina and transverse process, respectively. In anatomical studies, these two blocks showed different injectate spreading patterns to the back muscles and the fascial plane. In cadaveric studies, paravertebral spread was identified, but variable. However, numerous clinical reports have shown paravertebral spread with erector spinae plane blocks. Both techniques have been found to reduce postoperative pain compared to controls; however, the results have been more inconsistent than with the paravertebral block. Finally, the intertransverse process block targets the tissue complex posterior to the superior costotransverse ligament. Anatomical studies have revealed that this block has pathways that are more direct and closer to the paravertebral space than the retrolaminar and erector spinae plane blocks. Cadaveric evaluations have consistently shown promising results; however, further clinical studies using this technique are needed to confirm these anatomical findings.