The role of regional anaesthesia and multimodal analgesia in the prevention of chronic postoperative pain: a narrative review

Erector spinae plane block versus quadratus lumborum block for postoperative analgesia after laparoscopic nephrectomy: A randomized controlled trial

STUDY OBJECTIVE

We compared the analgesic effects of erector spinae plane block versus quadratus lumborum block following laparoscopic nephrectomy.

DESIGN

A randomized controlled trial.

SETTING

A tertiary hospital in Beijing, China.

PATIENTS

Patients scheduled for elective laparoscopic nephrectomy.

INTERVENTIONS

A total of 110 patients were enrolled and randomized to receive either erector spinae plane block (n = 55) or quadratus lumborum block (n = 55) under ultrasound guidance. Patient-controlled sufentanil analgesia was provided after surgery.

MEASUREMENTS

Our primary outcome was cumulative opioid consumption within 24 h after surgery. Secondary outcomes included postoperative pain intensity, subjective sleep quality, and quality of recovery.

MAIN RESULTS

All 110 patients (mean 53 years, 57.3% female) were included in the intention-to-treat analysis. Cumulative sufentanil equivalent within 24 h was lower in patients given erector spinae plane block (median 13 μg, interquartile range 4 to 33) than in those given quadratus lumborum block (median 25 μg, interquartile range 13 to 39; median difference - 8 μg, 95% CI -15 to 0, P = 0.041). Pain intensity (0-10 range where 0 = no pain and 10 = the worst pain) at 2, 6, 12, and 24 h after surgery was lower with erector spinae plane block (at rest: median differences -1 point, all P ≤ 0.009; with movement: median differences -2 to -1 points, all P < 0.001). Subjective sleep quality on the night of surgery (the Richards-Campbell Sleep Questionnaire: 0-100 range, higher score better; median difference 12, 95% CI 2 to 23, P = 0.018) and quality of recovery at 24 h (the Quality of Recovery-15: 0-150 range, higher score better; median difference 8, 95% CI 2 to 15, P = 0.012) were better with erector spinae plane block. No procedure-related adverse events occurred.

CONCLUSIONS

Compared with quadratus lumborum block, erector spinae plane block provided better analgesia as manifested by lower opioid consumption and pain intensity for up to 24 h after laparoscopic nephrectomy.

Quadratus lumborum block vs. transversus abdominis plane block for postoperative pain control in patients with nephrectomy: A systematic review and network meta-analysis

STUDY OBJECTIVE

This systematic review and network meta-analysis aimed to compare the analgesic efficacy of transversus abdominis plane block (TAPB) and quadratus lumborum block (QLB) on nephrectomy.

DESIGN

Systematic review and network meta-analysis.

PATIENTS

Patients undergoing nephrectomy.

INTERVENTIONS

TAPB and QLB for postoperative analgesia.

MEASUREMENTS

The primary outcome was 24 h morphine-equivalent consumptions after surgery. Secondary outcomes included postoperative pain scores, postoperative opioid consumption, postoperative rescue analgesia, postoperative nausea and vomiting (PONV), length of hospital stay after surgery, and patient satisfaction.

MAIN RESULTS

Fourteen studies involving 883 patients were included. Seven studies compared TAPB to control, six studies compared QLB to control, and one study compared TAPB to QLB. For direct meta-analysis of the post-surgical 24 h morphine-equivalent consumption, QLB was lower than control (mean difference [95%CI]: -18.16 [-28.96, -7.37]; I2 = 88%; p = 0.001), while there was no difference between TAPB and control (mean difference [95%CI]: -8.34 [-17.84, 1.17]; I2 = 88%; p = 0.09). Network meta-analysis showed similar findings that QLB was ranked as the best anesthetic technique for reducing postoperative 24 h opioid consumption (p-score = 0.854). Moreover, in direct meta-analysis, as compared to control, the time of first postoperative rescue analgesia was prolonged after QLB (mean difference [95%CI]: 165.00 [128.99, 201.01]; p < 0.00001), but not TAPB (mean difference [95%CI]: 296.82 [-91.92, 685.55]; p = 0.13). Meanwhile, QLB can effectively reduce opioid usages at intraoperative period, as well as at postoperative 6 h and 48 h, while TAPB can only reduce opioid consumption at 6 h after surgery. As compared to control, both TAPB and QLB exhibited the reduction in PONV and pain scores at post-surgical some timepoints. Also, QLB (mean difference [95%CI]: -0.29 [-0.49, -0.08]; p = 0.006) but not TAPB (mean difference [95%CI]: 0.60 [-0.25, 1.45]; p = 0.17) exhibited the shorter postoperative length of hospital stay than control.

CONCLUSIONS

QLB is more likely to be effective in reducing postoperative opioid use than TAPB, whereas both of them are superior to control with regard to the reduction in postoperative pain intensity and PONV.

TRIAL REGISTRATION

PROSPERO identifier: CRD42022358464.

Administration of flurbiprofen axetil and dezocine for the postoperative analgesia in patients with non‑small cell lung cancer: A randomized, controlled study

Flurbiprofen axetil or dezocine monotherapy has been applied for analgesia of postoperative non-small cell lung cancer (NSCLC); however, their combination is rarely investigated. Consequently, the present study aimed to explore the effect of flurbiprofen axetil plus dezocine on postoperative pain, surgical outcomes and its safety profile in patients with NSCLC. A total of 150 patients with resectable NSCLC were enrolled and randomized into three groups: i) The flurbiprofen axetil plus dezocine group (n=50), ii) the flurbiprofen axetil group (n=51) and iii) the dezocine group (n=49). A total of 50 mg flurbiprofen axetil, 5 mg of dezocine or their combination were administered intravenously 3 h prior to surgery and subsequently every 12 h until day 3 (D3) following surgery. The postoperative pain was lower in the flurbiprofen axetil plus dezocine group compared with that of the flurbiprofen axetil group at 6 h (P=0.008), 12 h (P=0.003), day 1 (D1) (P=0.013), day 2 (D2) (P=0.036) and D3 (P=0.010); in addition, it was lower in the flurbiprofen axetil plus dezocine group compared with that of the dezocine group at 6 h (P=0.010), 12 h (P=0.012) and D1 (P=0.020). Patient-controlled analgesia consumption was also lower in the flurbiprofen axetil plus dezocine group compared with that of the flurbiprofen axetil (P=0.010) and dezocine (P=0.002) groups. Furthermore, the length of hospital stay was lower in the flurbiprofen axetil plus dezocine group compared with that of the flurbiprofen axetil (P=0.008) and dezocine (P=0.048) groups, while other surgical outcomes and adverse events were similar among these three groups. Moreover, the expression of tumor necrosis factor-α was lower in the flurbiprofen axetil plus dezocine group compared with that of the dezocine group at 12 h (P<0.001), D1 (P<0.001) and D3 (P=0.033). The data indicated that flurbiprofen axetil and dezocine combination was superior to monotherapy for postoperative analgesia in patients with resectable NSCLC.

S-ketamine Infusion on Chronic Postoperative Pain Following Breast Cancer Surgery: A Randomized Double-Blind Placebo-Controlled Trial

BACKGROUND

Chronic postoperative surgical pain (CPSP) is a frequent complication following breast surgery and poses a challenge in terms of treatment. We hypothesized that the incidence of CPSP would be reduced at 3 months post-breast surgery with the administration of S-ketamine compared to a placebo.

PATIENTS AND METHODS

Participants were recruited and randomly assigned to either the S-ketamine group (S) or the control group (C). In group S, S-ketamine was administered as a 1.5 mg kg-1 bolus followed by 2 mg kg-1h-1 infusion, while in group C, a placebo of 0.9% saline was administered in the same volume and rate as S-ketamine. The primary outcome was the incidence of CPSP, measured using a 0-10 numeric rating scale (NRS), at 3 months postsurgery.

RESULTS

A total of 72 patients scheduled for mastectomy were enrolled (group S, n = 33; group C, n = 32). The incidence of CPSP at 3 months postsurgery was significantly lower in group S compared to group C (18.2% vs. 48.3%, P < .05). There was no statistical difference between the 2 groups in terms of the incidence of moderate to severe pain. NRS scores for postoperative pain at rest and during movement were significantly lower at 4 h and 24 h post-surgery (P < .05, respectively). Patients in Group S had lower Patient Health Questionnaire-9 (PHQ-9) scores at one week and 3 months post-surgery compared to Group C (P < .05, respectively).

CONCLUSION

S-ketamine infusion reduces the incidence of CPSP 3 months after breast surgery.

Efficacy and safety of ketamine as an adjuvant to regional anesthesia: A systematic review and meta-analysis of randomized controlled trials

STUDY OBJECTIVE

To identify whether adding ketamine to the local anesthetics (LA) in the regional anesthesia could prolong the duration of analgesia.

DESIGN

A Systematic review and meta-analysis of randomized controlled trials.

SETTING

The major dates were obtained in the operating room and the postoperative recovery ward.

PATIENTS

A total of 1011 patients at ASA physical status I and II were included in the analysis. Procedure performed including cesarean section, orthopedic, radical mastectomy, urological or lower abdominal surgery and intracavitary brachytherapy implants insertion.

INTERVENTIONS

After an extensive search of the electronic database, patients received regional anesthesia combined or not combined general anesthesia and with or without adding ketamine to LA were included in the analysis. The regional anesthesia includes spinal anesthesia, brachial plexus block, pectoral nerve block, transversus abdominis plane block and femoral and sciatic nerve block.

MEASUREMENT

The primary outcome was the duration of analgesia. Secondary outcomes were the duration and onset time of motor and sensory block as well as the ketamine-related adverse effect. Data are expressed in mean differences in continuous data and odds ratios (OR) for dichotomous data with 95% confidence intervals. The risk of bias of the included studies was evaluated using the revised Cochrane risk of bias tool for randomized trials. The quality of evidence for each outcome was rated according to the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) Working Group system.

MAIN RESULT

Twenty randomized controlled trials were included in the analysis. When ketamine was used as an adjuvant to LA, the duration of analgesia could be prolonged(172.21 min, 95% CI, 118.20 to 226.22; P<0.00001, I2 = 98%), especially in the peripheral nerve block(366.96 min, 95% CI, 154.19 to 579.74; P = 0.0007, I2 = 98%). Secondary outcomes showed ketamine could prolong the duration of sensory block(29.12 min, 95% CI, 10.22 to 48.01; P = 0.003, I2 = 96%) but no effect on the motor block(6.94 min, 95% CI,-2.65 to 16.53;P = 0.16, I2 = 84%), the onset time of motor and sensory block (motor onset time, -1.17 min, 95% CI, -2.67 to 0.34; P = 0.13, I2 = 100%; sensory onset time, -0.33 min, 95% CI,-0.87 to 0.20; P = 0.23, I2 = 96%) as well as the ketamine-related adverse effect(OR, 1.97, 95% CI,0.93 to 4.17;P = 0.08, I2 = 57%).

CONCLUSION

This study indicates that ketamine could be an ideal adjuvant to local anesthetics regardless of the types of anesthesia. Overall, the quality of the evidence is low.

The effects of combined acupuncture anesthesia and serratus anterior plane block with ropivacaine on postoperative analgesia in patients undergoing chest surgery

OBJECTIVE

To investigate the effects of combined acupuncture anesthesia and ropivacaine on postoperative analgesia and neuro-related factors in patients undergoing chest surgery.

METHODS

The analgesic drug dosage, postoperative PCIA pressing times, VAS scores at rest and during activity at 6 h (T1), 12 h (T2), 18 h (T3), and 24 h (T4) postoperatively.

RESULTS

The analgesic drug dosage and postoperative PCIA pressing times were lower in the observation group than in the control group (p < 0.05). The VAS scores at T1-T4 postoperatively were lower in the observation group than in the control group (p < 0.05). The SAS scores at T1-T4 postoperatively were lower in the observation group than in the control group (p < 0.05). The levels of IL-6 and IL-10 on postoperative day 1 were higher than those on preoperative day 1 in both groups, with a smaller change in the observation group (p < 0.05). The levels of S100β protein on postoperative day 1 were higher than those on preoperative day 1 in both groups, while the BDNF levels were lower, with a smaller change in the observation group (p < 0.05). There was no significant difference in the incidence of adverse reactions between the control group (11.36%) and the observation group (15.56%) (p > 0.05).

CONCLUSION

Combined acupuncture anesthesia and ropivacaine can effectively improve postoperative analgesia and agitation in patients undergoing chest surgery, reduce the dosage of analgesic drugs, regulate the levels of inflammatory factors and neurotrophic factors in patients, and do not increase the risk of adverse reactions related to patients.

Effects of intra-operative magnesium sulfate infusion on orthognathic surgery: A prospective and randomized controlled trial

Purpose

To comprehensively understand the effects of intra-operative infusion of magnesium sulfate on patients who underwent orthognathic surgery, including remifentanil consumption, postoperative pain, postoperative nausea and vomiting (PONV), inflammatory response, and serum magnesium levels.

Methods

Seventy-five adult patients undergoing orthognathic surgery under general balanced anesthesia were randomly divided into two groups. One group (Group M) received 50 mg/kg of magnesium sulfate in 20 mL 0.9 % saline after intubation, followed by a continuous infusion at a rate of 15 mg/kg/h until 30 min before the anticipated end of surgery. The other group (Group C) received an equal volume of isotonic saline as a placebo. (Clinical trial registration number: chiCTR2100045981).

Results

The primary outcome was remifentanil consumption. The secondary outcomes included the pain score assessed using the verbal numerical rating scale (VNRS) and PONV assessed using a Likert scale. Remifentanil comsumption in Group M was lower than Group C (mean ± SD: 0.146 ± 0.04 μg/kg/min vs. 0.173 ± 0.04 μg/kg/min, P = 0.003). At 2 h after surgery, patients in Group C suffered more severe PONV than those in Group M (median [interquartile range, IQR]: 1 [3] vs. 1 [0], mean rank: 31.45 vs. 42.71, P = 0.040). At post-anesthesia care unit (PACU), postoperative pain in Group C was severe than Group M (3 [1] vs. 3 [0], mean rank: 31.45 vs. 42.71, P = 0.013). Changes in haemodynamics and surgical field scores did not differ between the groups (all P > 0.05). The levels of cytokines (IL-4, IL-6, IL-8, IL-10, TNF-a, and MIP-1β) were not significantly different between the groups after surgery (all P > 0.05). Postoperative serum magnesium levels in Group C were lower than those in Group M (0.74 ± 0.07 mmol/L vs. 0.91 ± 0.08 mmol/L, P = 0.000) and the preoperative level (0.74 ± 0.07 mmol/L vs. 0.83 ± 0.06 mmol/L, P = 0.219).

Conclusions

In orthognathic surgery, magnesium sulfate administration can reduce remifentanil requirement and relieve PONV and postoperative pain in the early postoperative phase.

Research priorities in regional anaesthesia: an international Delphi study

BACKGROUND

Regional anaesthesia use is growing worldwide, and there is an increasing emphasis on research in regional anaesthesia to improve patient outcomes. However, priorities for future study remain unclear. We therefore conducted an international research prioritisation exercise, setting the agenda for future investigators and funding bodies.

METHODS

We invited members of specialist regional anaesthesia societies from six continents to propose research questions that they felt were unanswered. These were consolidated into representative indicative questions, and a literature review was undertaken to determine if any indicative questions were already answered by published work. Unanswered indicative questions entered a three-round modified Delphi process, whereby 29 experts in regional anaesthesia (representing all participating specialist societies) rated each indicative question for inclusion on a final high priority shortlist. If ≥75% of participants rated an indicative question as 'definitely' include in any round, it was accepted. Indicative questions rated as 'definitely' or 'probably' by <50% of participants in any round were excluded. Retained indicative questions were further ranked based on the rating score in the final Delphi round. The final research priorities were ratified by the Delphi expert group.

RESULTS

There were 1318 responses from 516 people in the initial survey, from which 71 indicative questions were formed, of which 68 entered the modified Delphi process. Eleven 'highest priority' research questions were short listed, covering themes of pain management; training and assessment; clinical practice and efficacy; technology and equipment.

CONCLUSIONS

We prioritised unanswered research questions in regional anaesthesia. These will inform a coordinated global research strategy for regional anaesthesia and direct investigators to address high-priority areas.

Management of acute postoperative pain: Conditions to guarantee the safety and effectiveness of analgesic treatments

The evidence on postoperative pain management is of low or insufficient quality. The SEDAR Acute Pain Working Group has prepared this guideline-document to apply the best available scientific evidence to clinical practice, individualizing it based on factors specific to the patient and the procedure, and encompassing different organizational options, attempting to individualize it based on specific factors of the patient and the procedure, and encompassing the different organizational options for pain control. The document updates concepts and minimum requirements necessary for optimal postoperative analgesia, a multidisciplinary approach and the management of Acute Postoperative Pain. Strategic lines and different management models are defined. A general perioperative action plan is established based on collaboration with the surgical departments involved, on the joint review of the evidence and on preparation of protocols by the procedure. Finally, a follow-up plan and a series of minimum indicators necessary for quality control of postoperative pain are presented.

Brief Assessment of Patient Phenotype to Explain Variability in Postsurgical Pain and Opioid Consumption after Cesarean Delivery: Performance of a Novel Brief Questionnaire Compared to Long Questionnaires

BACKGROUND

Understanding factors that explain why some women experience greater postoperative pain and consume more opioids after cesarean delivery is crucial to building an evidence base for personalized prevention. Comprehensive psychosocial assessment with validated questionnaires in the preoperative period can be time-consuming. A three-item questionnaire has shown promise as a simpler tool to be integrated into clinical practice, but its brevity may limit the ability to explain heterogeneity in psychosocial pain modulators among individuals. This study compared the explanatory ability of three models: (1) the 3-item questionnaire, (2) a 58-item questionnaire (long) including validated questionnaires (e.g., Brief Pain Inventory, Patient Reported Outcome Measurement Information System [PROMIS]) plus the 3-item questionnaire, and (3) a novel 19-item questionnaire (brief) assessing several psychosocial factors plus the 3-item questionnaire. Additionally, this study explored the utility of adding a pragmatic quantitative sensory test to models.

METHODS

In this prospective, observational study, 545 women undergoing cesarean delivery completed questionnaires presurgery. Pain during local anesthetic skin wheal before spinal placement served as a pragmatic quantitative sensory test. Postoperatively, pain and opioid consumption were assessed. Linear regression analysis assessed model fit and the association of model items with pain and opioid consumption during the 48 h after surgery.

RESULTS

A modest amount of variability was explained by each of the three models for postoperative pain and opioid consumption. Both the brief and long questionnaire models performed better than the three-item questionnaire but were themselves statistically indistinguishable. Items that were independently associated with pain and opioid consumption included anticipated postsurgical pain medication requirement, surgical anxiety, poor sleep, pre-existing pain, and catastrophic thinking about pain. The quantitative sensory test was itself independently associated with pain across models but only modestly improved models for postoperative pain.

CONCLUSIONS

The brief questionnaire may be more clinically feasible than longer validated questionnaires, while still performing better and integrating a more comprehensive psychosocial assessment than the three-item questionnaire.

EDITOR’S PERSPECTIVE

Pain Neuroscience Education in elective surgery patients: study protocol for a randomised controlled trial

BACKGROUND

Pain Neuroscience Education (PNE) consists of an educational strategy that seeks to understand the biological processes of pain and how to control it. The main objective of this study will be to evaluate the impact of PNE on outcomes related to the postoperative period. The hypothesis is that the intervention may positively influence postoperative recovery, contributing to pain control, clinical indications, acceptance and consumption of analgesics and other pharmacological drugs that contribute to its control, as well as psychological aspects, such as anxiety, depression and pain catastrophising.

METHODS AND ANALYSIS

This will be an open, parallel, multicentre and randomised controlled clinical trial. A total of 100 participants aged between 18 and 59 years of age, of both genders, who are going to have elective general surgery will be evaluated. The intervention group will participate in a preoperative pain neuroscience educational session and also receive usual preoperative care, while the control group receives usual preoperative care as well. The educational session will last 30 min and consists of a video (5:20 min), a questionnaire about the content, time for participants to express their beliefs, thoughts and doubts. Participants will be evaluated preoperatively and there will be one postintervention evaluation. The intensity and characteristics of pain and anxiety are evaluated as primary outcomes. As secondary outcomes, pain catastrophising and depression are taken into account.

ETHICS AND DISSEMINATION

The project was approved by the Research Ethics Committee of the Faculty of Ceilandia, the Research Ethics Committee of the Institute of Strategic Health Management of the Federal District and the Research Council of the Hospital of Brasília-Rede Dasa (CAAE: 28572420.3.0000.8093). Recruitment began in June of 2023. All participants were included in the study only after their written consent. All data obtained will be analysed and distributed through publication in journals and at scientific events.

TRIAL REGISTRATION NUMBER

Brazilian Registry of Clinical Trials (ReBEC) (RBR-23mr7yy).

Comparison between the effects of epidural and intravenous patient-controlled analgesia on postoperative disability-free survival in patients undergoing thoracic and abdominal surgery: A post hoc analysis

BACKGROUND

Thoracic epidural analgesia (TEA) and intravenous patient-controlled analgesia (IV-PCA) are widely used to mitigate immediate postoperative pain; however, their effects on long-term disability-free survival are poorly documented. This study aimed to compare the effects of postoperative TEA and IV-PCA on disability-free survival in patients who underwent thoracic or abdominal surgery.

METHODS

This post hoc analysis of a prospective observational study included 845 inpatients aged ≥55 years that underwent elective thoracic and abdominal surgery between 1 April 2016 and 28 December 2018 in a tertiary care hospital. Inverse probability of treatment weighted (IPTW) using stabilized inverse propensity scores was adopted to minimize bias. The primary outcome in this study was disability-free survival, defined as survival with a 12-item World Health Organization Disability Assessment Schedule 2.0 score of <16%, assessed at 3 months and 1 year after surgery.

RESULTS

The final analysis included 601 patients who received TEA and 244 who received IV-PCA. After IPTW, the weighted incidence of disability-free survival at 3 months and 1 year was 60.5% and 61.4% in the TEA group and 78.3% and 66.2% in the IV-PCA group, respectively. The adjusted OR for disability-free survival at 3 months and 1 year was 0.84 (95% confidence interval [CI]: 0.50-1.39) and 1.21 (95% CI: 0.72-2.05), respectively, for the TEA group.

CONCLUSION

No significant differences were observed in the disability-free survival at 3 months and 1 year after elective thoracic and abdominal surgery in patients aged ≥55 years who received TEA or IV-PCA.

SIGNIFICANCE STATEMENT

This study is the first in our setting to document the long-term effects of patient-controlled analgesia. In a post hoc analysis of our prospective cohort study, we show that although differences in chronic postsurgical pain exist at 3 months post-surgery, disability-free survival rates at 1 year do not differ irrespective of the choice of patient-controlled analgesia. The findings of this study highlight the need for shared decision-making between clinicians and patients.

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.

TEDOFA Trial Study Protocol: A Prospective Double-Blind, Randomized, Controlled Clinical Trial Comparing Opioid-Free versus Opioid Anesthesia on the Quality of Postoperative Recovery and Chronic Pain in Patients Receiving Thoracoscopic Surgery

Introduction

Seeking effective multimodal analgesia and anesthetic regimen is the basis for the success of ERAS. Opioid-free anesthesia (OFA) is a multimodal anesthesia associating hypnotics, N-methyl-D-aspartate (NMDA) antagonists, local anesthetics, anti-inflammatory drugs and α-2 agonists. Although previous studies have confirmed that OFA is safe and feasible for VATS surgery, there is great heterogeneity in how to select and combine anti-harm drugs to replace opioids. We hypothesized that the reduced opioid use during and after surgery allowed by OFA compared with standard of care will be associated with a reduction of postoperative opioid-related adverse events and an improvement in the quality of rehabilitation of patients after partial VATS lung resection.

Methods/Analysis

The TEDOFA Study is a prospective double-blind, randomized, controlled clinical trial with a concealed allocation of patients scheduled to undergo elective partial VATS pneumonectomy 1:1 to receive either a standard anesthesia protocol or an OFA. A total of 146 patients were recruited in the study. Primary endpoint was the 15-item recovery quality scale (QoR-15) at 24 hours after surgery.

Ethics and Dissemination

This trial has been approved by the Institutional Review Board of Beijing Friendship Hospital of China Capital University. The TEDOFA trial study protocol was approved on 27 February 2023. The trial started recruiting patients after registered on the Chinese Clinical Trial Registry.

Trial Registration Number

ChiCTR2300069210; Pre-results.

A secondary analysis: the impact of pre-existing chronic pain among patients with cancer presenting to the emergency department with acute pain

PURPOSE

Patients with cancer may experience pain from cancer itself or its treatment. Additionally, chronic pain (CP) predating a patient's cancer diagnosis may make the etiology of pain less clear and the management of pain more complex. In this brief report, we investigated differences in biopsychosocial characteristics, pain severity, and opioid consumption, comparing groups of cancer patients with and without a history of CP who presented to the emergency department (ED) with a complaint of cancer-related pain.

METHODS

This secondary analysis of a prospective cohort study included patients with cancer who presented to the ED with a complaint of pain (≥ 4/10). Sociodemographic, clinical, psychological, and pain characteristics were assessed in the ED and subsequent hospitalization. Mann-Whitney U-, T-, and Chi-square tests were used to compare differences between patients with and without pre-existing CP before cancer.

RESULTS

Patients with pre-existing CP had lower income (p = 0.21) and less formal education (p = 0.25) and were more likely to have a diagnosis of depression or substance use disorder (p < 0.01). Patients with pre-existing CP reported significantly greater pain severity in the ED and during hospitalization compared to those without pre-existing CP (p < 0.05), despite receiving greater amounts of opioid analgesics (p = 0.036).

CONCLUSION

Identifying a history of pre-existing CP during intake may help identify patients with cancer with difficult to manage pain, who may particularly benefit from multimodal interventions and supportive care. In addition, referral of these patients for the management of co-occurring pain disorders may help decrease the usage of the ED for undertreated pain.

Comparison of a blind and an ultrasound-guided technique for Retrobulbar anesthesia in dogs undergoing unilateral subconjunctival enucleation

OBJECTIVE

This study compared the quality of retrobulbar anesthesia using a blind inferior-temporal palpebral approach (ITP) with an ultrasound-guided supratemporal (ST) technique in dogs undergoing unilateral enucleation.

ANIMAL STUDIED

Twenty-one client-owned dogs were undergoing enucleation.

PROCEDURES

Dogs were randomly assigned to receive ITP (n = 10) or ST (n = 11) with 0.5% ropivacaine at 0.1 mL/cm of neurocranial length. The anesthetist was blinded to the technique. Intraoperative data included cardiopulmonary variables, inhalant anesthetics requirement, and requirement for rescue analgesia (intravenous fentanyl 2.5 mcg/kg). Postoperative data included pain scores, sedation scores, and need for intravenous hydromorphone (0.05 mg/kg). Treatments were compared using Wilcoxon's rank sum test or Fisher's exact test as appropriate. Comparison of variables over time were tested using a mixed effect linear model on rank. Significance was set at p = 0.05.

RESULTS

Intraoperative cardiopulmonary variables and inhalant requirements were not different between groups. Dogs receiving ITP required median (interquartile range, IQR) 1.25 (0, 2.5) mcg/kg intraoperative fentanyl while those receiving ST required none (p < 0.01). Intraoperative fentanyl was required in 5/10 and 0/11 of dogs in the ITP and ST groups, respectively (p = 0.01). Postoperative analgesia requirements were not significantly different between groups; 2/10 and 1/10 dogs in the ITP and ST groups, respectively. Sedation score negatively affected pain score (p < 0.01).

CONCLUSIONS

The ultrasound-guided ST technique was more effective at decreasing intraoperative opioid requirements than the blind ITP approach in dogs undergoing unilateral enucleation.

A systematic review of the added value of perioperative pain neuroscience education

OBJECTIVE

To identify and summarize evidence about the benefits of perioperative pain neuroscience education (PNE) on pain-related and psychosocial outcomes.

METHODS

Included were reports written in English that carried out PNE or its synonyms; perioperative period; aged ≥ 18 years; interventional studies and observational studies. Secondary studies, conference abstracts, and editorials were excluded. There was no time limitation.

INFORMATION SOURCES

PubMed, Virtual Health Library, Cochrane Library, and Science Direct. Search: June 20th 2023. The risk of bias was assessed using the Joanna Briggs Institute checklists, and synthesis followed the recommendations of the Synthesis Without Meta-analysis (SWiM) guideline. Register: Center for Open Science website (10.17605/OSF.IO/ZTNEJ).

RESULTS

The sample consisted of 18 reports. For pain outcomes, it was not possible to attribute PNE benefits because ten reports found improvements in both intervention and control groups. For psychosocial outcomes, fourteen reports found benefits for PNE groups. All the analyzed reports showed low risk of bias.

CONCLUSION

PNE had additional benefits beyond those obtained with conventional treatment for psychosocial outcomes.

PRACTICAL IMPLICATIONS

Due to the lack of evidence, it was not possible to indicate the clinical use of PNE. It is suggested that further studies are needed aimed at clarifying the possible benefits.

Mechanisms inherent in acute-to-chronic pain after surgery - risk, diagnostic, predictive, and prognostic factors

PURPOSE OF REVIEW

Pain is an expected consequence of a surgery, but it is far from being well controlled. One major complication of acute pain is its risk of persistency beyond healing. This so-called chronic post-surgical pain (CPSP) is defined as new or increased pain due to surgery that lasts for at least 3 months after surgery. CPSP is frequent, underlies a complex bio-psycho-social process and constitutes an important socioeconomic challenge with significant impact on patients' quality of life. Its importance has been recognized by its inclusion in the eleventh version of the ICD (International Classification of Diseases).

RECENT FINDINGS

Evidence for most pharmacological and non-pharmacological interventions preventing CPSP is inconsistent. Identification of associated patient-related factors, such as psychosocial aspects, comorbidities, surgical factors, pain trajectories, or biomarkers may allow stratification and selection of treatment options based on underlying individual mechanisms. Consequently, the identification of patients at risk and implementation of individually tailored, preventive, multimodal treatment to reduce the risk of transition from acute to chronic pain is facilitated.

SUMMARY

This review will give an update on current knowledge on mechanism-based risk, prognostic and predictive factors for CPSP in adults, and preventive and therapeutic approaches, and how to use them for patient stratification in the future.

Development and prospective validation of postoperative pain prediction from preoperative EHR data using attention-based set embeddings

Preoperative knowledge of expected postoperative pain can help guide perioperative pain management and focus interventions on patients with the greatest risk of acute pain. However, current methods for predicting postoperative pain require patient and clinician input or laborious manual chart review and often do not achieve sufficient performance. We use routinely collected electronic health record data from a multicenter dataset of 234,274 adult non-cardiac surgical patients to develop a machine learning method which predicts maximum pain scores on the day of surgery and four subsequent days and validate this method in a prospective cohort. Our method, POPS, is fully automated and relies only on data available prior to surgery, allowing application in all patients scheduled for or considering surgery. Here we report that POPS achieves state-of-the-art performance and outperforms clinician predictions on all postoperative days when predicting maximum pain on the 0-10 NRS in prospective validation, though with degraded calibration. POPS is interpretable, identifying comorbidities that significantly contribute to postoperative pain based on patient-specific context, which can assist clinicians in mitigating cases of acute pain.

A random forest algorithm-based prediction model for moderate to severe acute postoperative pain after orthopedic surgery under general anesthesia

BACKGROUND

Postoperative pain is one of the most common complications after surgery. In order to detect early and intervene in time for moderate to severe postoperative pain, it is necessary to identify risk factors and construct clinical prediction models. This study aimed to identify significant risk factors and establish a better-performing model to predict moderate to severe acute postoperative pain after orthopedic surgery under general anesthesia.

METHODS

Patients who underwent orthopedic surgery under general anesthesia were divided into patients with moderate to severe pain group (group P) and patients without moderate to severe pain group (group N) based on VAS scores. The features selected by Lasso regression were processed by the random forest and multivariate logistic regression models to predict pain outcomes. The classification performance of the two models was evaluated through the testing set. The area under the curves (AUC), the accuracy of the classifiers, and the classification error rate for both classifiers were calculated, the better-performing model was used to predict moderate to severe acute postoperative pain after orthopedic surgery under general anesthesia.

RESULTS

A total of 327 patients were enrolled in this study (228 in the training set and 99 in the testing set). The incidence of moderate to severe postoperative pain was 41.3%. The random forest model revealed a classification error rate of 25.2% and an AUC of 0.810 in the testing set. The multivariate logistic regression model revealed a classification error rate of 31.3% and an AUC of 0.764 in the testing set. The random forest model was chosen for predicting clinical outcomes in this study. The risk factors with the greatest and second contribution were immobilization and duration of surgery, respectively.

CONCLUSIONS

The random forest model can be used to predict moderate to severe acute postoperative pain after orthopedic surgery under general anesthesia, which is of potential clinical application value.

Advances in Anesthesia for Shoulder Surgery: A Comprehensive Review of Dexmedetomidine-Enhanced Interscalene Brachial Plexus Block

Surgical procedures on the shoulder pose distinctive challenges in managing pain during the perioperative period, underscoring the importance of exploring innovative anesthesia techniques. This comprehensive review article delves into integrating dexmedetomidine, an alpha-2 adrenergic agonist, within interscalene brachial plexus blocks for shoulder surgery. The review initiates by underscoring the pivotal role of effective anesthesia in shoulder surgery and elucidates the rationale behind investigating dexmedetomidine as an adjunct. It meticulously examines the anatomy and physiology of the brachial plexus, emphasizing its critical significance in shoulder surgery. Furthermore, the article expounds on dexmedetomidine's mechanisms of action and pharmacokinetics, encompassing its safety profile and potential side effects. The conventional interscalene brachial plexus block techniques, along with their limitations and challenges, are discussed, laying the foundation for the integration of dexmedetomidine. The review subsequently delves into exploring the role of dexmedetomidine in regional anesthesia, covering previous studies, mechanisms of action, and the potential advantages of incorporating it into nerve blocks. The review's core concentrates on the practical application of dexmedetomidine-enhanced interscalene brachial plexus blocks. This includes discussions on administration techniques, dosage guidelines, and compelling evidence supporting its utilization. Clinical scenarios where this approach proves most advantageous are thoroughly explored, comparing its effectiveness with traditional techniques in terms of pain control and patient outcomes. A comprehensive examination of relevant clinical trials and case studies highlights the evidence supporting its efficacy. The review also underscores safety considerations associated with dexmedetomidine. It proposes strategies for mitigating risks to ensure patient safety. Insights into future directions and research are provided, encompassing ongoing studies, areas necessitating further investigation, and potential refinements in technique. Finally, the article summarizes key findings, emphasizing the practicality of dexmedetomidine-enhanced interscalene brachial plexus blocks in shoulder surgery and its far-reaching implications for clinical practice and patient care.

Efficacy and safety of thoracoscopic-guided multiple paravertebral block for video-assisted thoracoscopic lobectomy surgery: a randomized blinded controlled study

Background

Paravertebral block (PVB) has been increasingly popular for postoperative analgesia. However, few studies estimated the efficacy and safety of multiple PVB using thoracoscope-assisted technique for intraoperative analgesia and postoperative pain management for video-assisted thoracoscopic lobectomy (VATS LOBECTOMY).

Methods

A total of 120 patients scheduled to undergo VATS LOBECTOMY were randomly assigned into two groups: a placebo group and a PVB group in a ratio of 1:2. Thoracoscopic-guided multi-point PVB was carried out with 0.5% ropivacaine (PVB group) or 0.9% NaCl (placebo group) at the beginning and the end of surgery. The primary endpoint was consumption of intraoperative opioid.

Results

Consumption rate of intraoperative opioids was significantly lower in the PVB group (878.14 ± 98.37 vs. 1,432.20 ± 383.53 for remifentanil; 123.83 ± 17.98 vs. 266.42 ± 41.97 for fentanyl). Postoperatively, significantly longer duration of using patient-controlled intravenous analgesia for the first time, reduced times of analgesic pump pressing, and less rescue analgetic consumption were observed in the PVB group. Visual analog scale scores at rest and during exercising were significantly lower in the PVB group at all time points within the first 48 h after surgery. The PVB group was also associated with significantly higher total QoR-40 scores and lower incidence of analgesia-related adverse events.

Conclusions

Thoracoscopic-guided multiple PVB was a simple and effective technique in controlling pain both intra- and postoperatively for VATS LOBECTOMY. It was also associated with the absence of detrimental effects attributed to opioid overuse and benefits of the early resumption of activity and physical function recovery. Therefore, this regional anesthesia technique should be advocated as part of a multimodal analgesia protocol for VATS LOBECTOMY.

[Factors influencing the chronic post-surgical pain after laparoscopic surgery for elderly patients with urinary tract tumors]

OBJECTIVE

To investigate the incidence and potential influence factors that contribute to chronic post-surgical pain (CPSP) in elderly patients with urinary tract tumors who underwent laparoscopic procedures.

METHODS

A retrospective study was conducted to collect the clinical data of 182 elderly patients with urinary tract tumors who were ≥65 years and underwent laparoscopic surgery from October 2021 to March 2022 in Peking University Third Hospital. The patients'demographic information, medical history and the severity of postoperative pain were collected. Telephone follow-ups were made 6 months after surgery, and the patients' CPSP conditions were recorded. The diagnostic criteria of CPSP were referred to the definition made by the International Association for the Study of Pain (IASP): (1) Pain that developed or increased in intensity after surgical procedure and persisted for at least 3 months after surgery; (2) Pain that localized to the surgical field or projected to the innervation territory of a nerve situated around the surgical area; (3) Pain due to pre-existing pain conditions or infections and malignancy was excluded. The patients were divided into two groups based on CPSP diagnosis. Risk factors that predisposed the patients to CPSP were identified using univariate analysis. A multivariate Logistic regression model using back-forward method was designed, including both variables that significantly associated with CPSP in the univariate analysis (P < 0.1), and the variables that were considered to have significant clinical impact on the outcome.

RESULTS

Two hundred and sixteen patients with urinary tract tumors who had undergone laparoscopic surgery were included, of whom, 34 (15.7%) were excluded from the study. For the remaining 182 patients, the average age was (72.6±5.2) years, with 146 males and 36 females. The incidence of CPSP at the end of 6 months was 31.9% (58/182). Multiva-riate regression analysis revealed that age ≥75 years (OR=0.29, 95% CI: 0.12-0.73, P=0.008) was the protecting factors for postoperative chronic pain in the elderly patients with urinary tract tumors undergoing surgical treatment, while renal cancer (compared with other types of urinary tract tumors) (OR=3.68, 95% CI: 1.58-8.58, P=0.003), and the 24 h postoperative moderate to severe pain (OR=2.57, 95% CI: 1.14-5.83, P=0.024) were the independent risk factors affecting CPSP.

CONCLUSION

Age < 75 years, renal cancer and the 24 h postoperative moderate to severe pain are influence factors of the occurrence of CPSP after laparoscopic surgery in elderly patients with urinary tract tumors. Optimum postoperative multimodal analgesia strategies are suggested to prevent the occurrence of CPSP.

Rhomboid intercostal block or thoracic paravertebral block for postoperative recovery quality after video-assisted thoracic surgery: A prospective, non-inferiority, randomised controlled trial

BACKGROUND

The analgesic characteristics of rhomboid intercostal block (RIB) remain unclear. Before it can be fully recommended, we compared the recovery quality and analgesic effects of RIB and thoracic paravertebral block (TPVB) for video-assisted thoracoscopic surgery (VATS).

OBJECTIVE

The current study aimed to investigate whether there is a difference in postoperative recovery quality between TPVB and RIB.

DESIGN

A prospective, non-inferiority, randomised controlled trial.

SETTING

Affiliated Hospital of Jiaxing University in China from March 2021 to August 2022.

PATIENTS

Eighty patients aged 18 to 80 years, with ASA physical status I to III, and scheduled for elective VATS were enrolled in the trial.

INTERVENTION

Ultrasound-guided TPVB or RIB was performed with 20 ml 0.375% ropivacaine.

MAIN OUTCOME MEASURES

The primary outcome of the study was the mean difference of quality of recovery-40 scores 24 h postoperatively. The non-inferiority margin was defined as 6.3. Numeric rating scores (NRS) for pain at 0.5, 1, 3, 6, 12, 24 and 48 h postoperatively in all patients were also recorded.

RESULTS

A total of 75 participants completed the study. The mean difference of quality of recovery-40 scores 24 h postoperatively was -1.6 (95% CI, -4.5 to 1.3), demonstrating the non-inferiority of RIB to TPVB. There was no significant difference between the two groups in the area under the curve for pain NRS over time, at rest and on movement, at 6, 12, 24 and 48 h postoperatively (all P  > 0.05), except for the area under the curve pain NRS over time on movement at 48 h postoperatively ( P  = 0.046). There were no statistical differences between the two groups in the postoperative sufentanil use at 0 to 24 h or 24 to 48 h (all P  > 0.05).

CONCLUSION

Our study suggests that RIB was non-inferior to TPVB for the quality of recovery, with almost the same postoperative analgesic effect as TPVB after VATS.

CLINICAL TRIAL REGISTRATION

chictr.org.cn: ChiCTR2100043841.

Current Approaches to Four Challenging Pain Syndromes

During a conference of pain specialists, some of the experts addressed the potential management of four prevalent but difficult painful conditions, namely, chronic postsurgical pain (CPSP), knee osteoarthritis, chest trauma, and facet joint arthropathy. In all cases, the conditions posed challenges in accurate diagnoses as well as safe, effective treatments, especially using locoregional blocks. It is not clear why some surgical patients develop CPSP and others do not, although some risk factors have been identified. More importantly, the transitional phase of pain from acute to chronic deserves greater scrutiny. It appears as if more aggressive and more effective perioperative and postoperative analgesia could help mitigate or possibly prevent CPSP. Knee osteoarthritis is prevalent but is often managed pharmacologically and then with joint replacement; many patients simply live with the condition which can be viewed as a disease of the entire joint. New approaches with intra-articular injections of hyaluronic acid, platelet-rich plasma, and botulinum toxin may provide safe, effective, and durable pain control. Chest trauma can be extremely painful and a source of morbidity, but its management tends to rely on watchful waiting and drug therapy. New approaches to regional nerve blocks can be beneficial and may reduce troublesome symptoms such as the inability to cough or clear the lungs. Facet joint arthropathy is very prevalent among older people but is not completely clarified. It may be the source of intense pain with limited management strategies. The role of nerve blocks in facet joint arthropathy is an important new addition to the armamentarium of pain management, particularly for geriatric patients.

Protocol for Development and Validation of Multivariable Prediction Models for Chronic Postsurgical Pain Following Video-Assisted Thoracic Surgery

Purpose

Chronic postsurgical pain (CPSP) is a common complication after thoracic surgery and associated with long-term adverse outcomes. This study aims to develop two prediction models for CPSP after video-assisted thoracic surgery (VATS).

Methods and Analysis

This single-center prospective cohort study will include a total of 500 adult patients undergoing VATS lung resection (n = 350 for development and n = 150 for external validation). Patients will be enrolled continuously at The First Affiliated Hospital of Soochow University in Suzhou, China. The cohort for external validation will be recruited in another time period. The outcome is CPSP, which is defined as pain with the numerical rating scale score of 1 or higher 3 months after VATS. Univariate and multivariable logistic regression analyses will be performed to develop two CPSP prediction models based on patients' data of postoperative day 1 and day 14, respectively. For internal validation, we will use the bootstrapping validation technique. For external validation, the discrimination capability of the models will be assessed using the area under the receiver operating characteristic curve, and the calibration will be evaluated using the calibration curve and Hosmer-Lemeshow goodness-of-fit statistic. The results will be presented in model formulas and nomograms.

Conclusion

Based on the development and validation of the prediction models, our results contribute to early prediction and treatment of CPSP after VATS.

Trial Registration

Chinese Clinical Trial Register (ChiCTR2200066122).

Identifying risk factors for chronic postsurgical pain and preventive measures: a comprehensive update

INTRODUCTION

Chronic postsurgical pain (CPSP) is a prevalent condition that can diminish health-related quality of life, cause functional deficits, and lead to patient distress. Rates of CPSP are higher for certain types of surgeries than others (thoracic, breast, or lower extremity amputations) but can occur after even uncomplicated minimally invasive procedures. CPSP has multiple mechanisms, but always starts as acute postsurgical pain, which involves inflammatory processes and may encompass direct or indirect neural injury. Risk factors for CPSP are largely known but many, such as female sex, younger age, or type of surgery, are not modifiable. The best strategy against CPSP is to quickly and effectively treat acute postoperative pain using a multimodal analgesic regimen that is safe, effective, and spares opioids.

AREAS COVERED

This is a narrative review of the literature.

EXPERT OPINION

Every surgical patient is at some risk for CPSP. Control of acute postoperative pain appears to be the most effective approach, but principles of good opioid stewardship should apply. The role of regional anesthetics as analgesics is gaining interest and may be appropriate for certain patients. Finally, patients should be better informed about their relative risk for CPSP.

Multiorganizational consensus to define guiding principles for perioperative pain management in patients with chronic pain, preoperative opioid tolerance, or substance use disorder

Significant knowledge gaps exist in the perioperative pain management of patients with a history of chronic pain, substance use disorder, and/or opioid tolerance as highlighted in the US Health and Human Services Pain Management Best Practices Inter-Agency Task Force 2019 report. The report emphasized the challenges of caring for these populations and the need for multidisciplinary care and a comprehensive approach. Such care requires stakeholder alignment across multiple specialties and care settings. With the intention of codifying this alignment into a reliable and efficient processes, a consortium of 15 professional healthcare societies was convened in a year-long modified Delphi consensus process and summit. This process produced seven guiding principles for the perioperative care of patients with chronic pain, substance use disorder, and/or preoperative opioid tolerance. These principles provide a framework and direction for future improvement in the optimization and care of 'complex' patients as they undergo surgical procedures.

Analgesic Efficacy of COX-2 Inhibitors in Periodontal Surgery: A Systematic Review and Meta-Analysis

The objective of this systematic review and meta-analysis was to evaluate the analgesic efficacy of COX-2 inhibitors versus other drugs in periodontal surgery. Two researchers searched PubMed, Google Scholar, ACM Digital, BASE, EBSCOhost, Scopus, or Web of Science for clinical trials using various combinations of words. All articles that met the selection criteria were assessed using the Cochrane Collaboration’s risk of bias tool. For data analysis, the inverse variance and mean difference statistical method was used with Review Manager 5.3 software for Windows. According to the conclusion of each study (qualitative evaluation), only one clinical trial had results in favor of a COX-2 inhibitor when compared to placebo, one clinical study informed that a COX-2 was better that an active control, four studies showed similar analgesic efficacy to active controls, and one clinical study informed the analgesic effect of one celecoxib-caffeine combination in comparison with celecoxib alone and placebo (n = 337). The COX-2 inhibitors showed a decrease in the rescue analgesic consumption (n = 138; I2 = 15%; mean difference = −0.31; 95%CIs = −0.6 to −0.01), and lower pain intensity at four hours (n = 178; I2 = 0%; mean difference = −2.25; 95%CIs = −2.94 to −1.55; p = 0.00001) when compared to active controls after periodontal surgery. In conclusion, the data indicate that COX-2 agents produce better pain relief in comparison to placebo and other drugs after periodontal surgery.

Stellate Ganglion Block Improves Postoperative Sleep Quality and Analgesia in Patients with Breast Cancer: A Randomized Controlled Trial

INTRODUCTION

Postoperative impaired sleep quality and pain are associated with adverse outcomes. Stellate ganglion block (SGB) has shown promising results in enhancing sleep quality and alleviating neuropathic pain. This study aimed to investigate the effects of ultrasound-guided SGB on postoperative sleep quality and pain in patients undergoing breast cancer surgery.

METHODS

This study is a parallel-group randomized controlled clinical trial with two groups: SGB and control. Fifty female patients undergoing breast cancer surgery were randomized in a 1:1 ratio to receive preoperative ultrasound-guided single-injection SGB (SGB group) or just an ultrasound scan (control group). All participants were blinded to the group assignment. The primary outcome was postoperative sleep quality, assessed by the St. Mary's Hospital Sleep Questionnaire and actigraphy 2 days postoperatively. The secondary outcome was postoperative pain, measured by the visual analog scale.

RESULTS

A total of 48 patients completed the study, with 23 patients in the control group and 25 in the SGB group. The postoperative St. Mary's Hospital Sleep Questionnaire scores were significantly higher in the SGB group than in the control group on 1 day postoperative (30.88 ± 2.44 versus 27.35 ± 4.12 points, P = 0.001). The SGB also increased the total sleep time and sleep efficiency (main actigraphy indicators) during the first two postoperative nights. Compared with the control group, preoperative SGB reduced postoperative pain and the incidence of breast cancer-related lymphedema (20% versus 52.2%, P = 0.02, odds ratio 0.229, 95% confidence interval 0.064-0.821). There were no adverse events related to SGB.

CONCLUSION

Preoperative ultrasound-guided SGB improves postoperative sleep quality and analgesia in patients undergoing breast cancer surgery. SGB may be a safe and practical treatment to enhance the postoperative quality of life in patients with breast cancer.

TRIAL REGISTRATION

The study was registered in the Chinese Clinical Trial Registry (ChiCTR2100046620, principal investigator: Kai Zeng, date of registration: 23 May 2021).

One year follow-up on a randomized study investigating serratus anterior muscle and pectoral nerves type I block to reduced neuropathic pain descriptors after mastectomy

Breast cancer is the second most common diagnosed type of cancer in women. Chronic neuropathic pain after mastectomy occurs frequently and is a serious health problem. In our previous single-center, prospective, randomized controlled clinical study, we demonstrated that the combination of serratus anterior plane block (SAM) and pectoral nerve block type I (PECS I) with general anesthesia reduced acute postoperative pain. The present report describes a prospective follow-up study of this published study to investigate the development of chronic neuropathic pain 12 months after mastectomy by comparing the use of general anesthesia alone and general anesthesia with SAM + PECS I. Additionally, the use of analgesic medication, quality of life, depressive symptoms, and possible correlations between plasma levels of interleukin (IL)-1 beta, IL-6, and IL-10 collected before and 24 h after surgery as predictors of pain and depression were evaluated. The results showed that the use of SAM + PECS I with general anesthesia reduced numbness, hypoesthesia to touch, the incidence of patients with chronic pain in other body regions and depressive symptoms, however, did not significantly reduce the incidence of chronic neuropathic pain after mastectomy. Additionally, there was no difference in the consumption of analgesic medication and quality of life. Furthermore, no correlation was observed between IL-1 beta, IL-6, and IL-10 levels and pain and depression. The combination of general anesthesia with SAM + PECS I reduced the occurrence of specific neuropathic pain descriptors and depressive symptoms. These results could promote the use of SAM + PECS I blocks for the prevention of specific neuropathic pain symptoms after mastectomy.Registration of clinical trial: The Research Ethics Board of the Hospital Sirio-Libanes/Brazil approved the study (CAAE 48721715.0.0000.5461). This study is registered at Registro Brasileiro de Ensaios Clinicos (ReBEC), and ClinicalTrials.gov, Identifier: NCT02647385.

Effects of Early Weight-Bearing Treadmill Training Combined with Pre-Emptive Analgesia on Femoral Fracture Recovery

Background

The effect of pre-emptive analgesia plus early weight-bearing treadmill training (EWBTT) on healing and motor function recovery of femoral shaft fracture is not clear.

Methods

A total of 60 SD male rats were randomly allocated into 4 groups: group A (pre-emptive analgesia with EWBTT), group B (pre-emptive analgesia with delayed weight-bearing treadmill training, DWBTT), group C (pre-emptive analgesia with no weight-bearing), and group D (EWBTT with no pre-emptive analgesia). All rats were molded by internal fixation with Kirschner wire after right femoral shaft fracture. In groups A, B, and C, tramadol was intramuscularly injected 15 minutes before surgery. EWBTT was performed at day 1 postoperatively in groups A and D, and DWBTT was performed at day 14 postoperatively in group B. Oblique plate test was accomplished to assess hindlimb motor function recovery of rats in each group. Status of fracture healing was assessed through digital radiography (DR). Hematoxylin-eosin (HE) staining and immunohistochemistry of bone morphogenetic protein-2 (MBP-2) and vascular endothelial growth factor (VEGF) in callus were performed to explore fracture healing. The expression of BMP-2 and VEGF protein in quadriceps femoris muscle was detected by Western blot technique and mRNA expression of BMP-2 and VEGF in callus ascertained via reverse transcription-polymerase chain reaction (RT-PCR) technique.

Results

For oblique plate test, rats in group A outperformed those in groups B and C at all time points after operation. DR image revealed that large numbers of callus growth, blurred fracture line, and obvious continuous callus passing through the fracture line can be found in group A at day 28 postoperatively, which is the best healing status among all groups. HE staining of callus confirmed the optimal effect of healing for rats in group A. VEGF and BMP-2 expression by immunohistochemistry showed a significantly higher positive score for callus in group A while those in group C being the lowest at all time points postoperatively. Significantly higher expression level of VEGF and BMP-2 protein was detected in quadriceps femoris muscle from group A, which exceeded those in all other groups at all time points. RT-PCR testing proved the highest expression of BMP-2 and VEGF mRNA in callus of rats from group A, significantly higher than those of other groups.

Conclusions

Both pre-emptive analgesia and EWBTT can effectively invoke the expression of VEGF and BMP-2 and promote recovery of hindlimb locomotor function in rats with femoral fracture, and the combination of them leads to more superior results.

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

The efficiency of ultrasound-guided erector spinae plane block in early cervical cancer patients undergoing laparotomic radical hysterectomy: A double-blind randomized controlled trial

Aims

We aim to compare the efficiency of erector spinae plane block (ESPB) with transversus abdominis plane block (TAPB) in patients undergoing laparotomic radical hysterectomy because only a few studies are reported exploring this matter.

Methods

In this randomized controlled trail, 154 eligible patients were randomly allocated into ESPB group [ESPB + patient-controlled intravenous analgesia (PCIA)] and TAPB group (TAPB + PCIA) at 1:1 ratio. The primary outcome was visual analog scale (VAS) score at rest state at 12 h.

Results

We found that ESPB group was associated with the lower VAS scores at rest and cough state than TAPB group at 2, 4, 6, 12, and 24 h postoperatively (P < 0.05). Less analgesic consumption and sufentanil consumption in PCIA pump were found in the ESPB group (P < 0.05). Moreover, ESPB group was followed by fewer rescue analgesia requirements, less rescue analgesic consumption, less adverse reactions, and higher analgesia satisfaction (P < 0.05).

Conclusions

Our study found that ESPB had advantages on analgesic effect and opioids consumption. In the future, more studies were needed to confirm our findings. Systematic Review Registration: https://www.chictr.org.cn/index.aspx, identifier: ChiCTR2100044240.

Successful use of differential target multiplexed spinal cord stimulation for chronic postsurgical abdominal pain

Introduction

Recent advances in stimulation techniques have improved the efficacy and expanded the applicability of spinal cord stimulation (SCS). Among these techniques, there are no reports on the efficacy of differential target multiplexed (DTM) SCS for chronic postsurgical pain (CPSP) after abdominal surgery. Therefore, we present the successful use of DTM SCS for CPSP after distal pancreatectomy.

Methods

A 49-year-old man with hypertension and severe chronic low back pain presented with neuropathic CPSP involving the left abdomen in the area of a laparotomy incision. His pain was refractory to conservative treatment and was rated 10 on a numerical rating scale (NRS). He underwent permanent implantation of a pulse generator after a 14-day trial stimulation.

Results

Chronic postsurgical pain was well controlled (NRS 1-2) at a 3-month follow-up with DTM SCS.

Conclusion

Differential target multiplexed SCS can be a new treatment option for neuropathic CPSP that is resistant to conservative treatment. It is important to further examine the characteristics of CPSP and identify appropriate candidates for the successful use of DTM SCS.

Inhibition effect of choline and parecoxib sodium on chronic constriction nerve injury-induced neuropathic pain in rats

PURPOSE

The simultaneous use of drugs with different mechanisms of analgesic action is a strategy for achieving effective pain control while minimizing dose-related side effects. Choline was described to potentiate the analgesic action of parecoxib sodium at small doses in several inflammatory pain models. However, these findings are still very limited, and more associated data are required to confirm the effectiveness of the combined choline and parecoxib sodium therapy against inflammatory pain.

METHODS

Adult rats were randomly divided into 9 groups (N = 6/group). The sham surgery group received an intraperitoneal (i.p.) injection of saline. Rats with chronic constriction injury (CCI) of the sciatic nerve received saline, choline (cho, 6, 12 and 24 mg/kg), parecoxib sodium (pare, 3, 6, and 12 mg/kg), or a combination of choline 6 mg/kg and parecoxib sodium 3 mg/kg. Mechanical and heat pain thresholds were measured at 30 min after drug treatment at Days 3, 5, 7, 10, and 14 after CCI. Another 30 rats were divided into 5 groups (N = 6/group): the sham, CCI + saline, CCI + cho-6 mg/kg, CCI + pare-3 mg/kg, and CCI + cho-6 mg/kg + pare-3 mg/kg groups. After repeated drug treatment for 7 days, five rats were randomly selected from each group, and the lumbar dorsal root ganglia (DRGs) (L4-6) were harvested for western blot analysis.

RESULTS

Choline significantly attenuated mechanical and heat hypersensitivity in CCI rats at 12 and 24 mg/kg doses (P < 0.05) but was not effective at the 6 mg/kg dose. Parecoxib sodium exerted significant pain inhibitory effects at the 6 and 12 mg/kg doses (P < 0.05) but not at the 3 mg/kg dose. Combining a low dose of choline (6 mg/kg) and parecoxib sodium (3 mg/kg) produced significant pain inhibition in CCI rats and reduced the expression of high mobility group protein 1 (HMGB1) and nuclear factor-kappa Bp65 (NF-κBp65) in L4-6 DRGs.

CONCLUSION

1. In a rat model of chronic neuropathic pain (CCI), at a certain dose, choline or parecoxib sodium can alleviate mechanical pain and thermal hyperalgesia caused by CCI. 2. The combination of choline and parecoxib sodium in nonanalgesic doses can effectively relieve neuropathic pain, and its mechanism may be related to the inhibition of the high mobility group protein 1 (HMGB1)/Toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) pathway.

Opioid-Sparing Analgesic Effects from Interscalene Block Impact Anesthetic Management During Shoulder Arthroscopy: A Retrospective Observational Study

Purpose

Ultrasound-guided interscalene nerve block (UISB) is commonly used to alleviate postoperative pain during shoulder arthroscopy. This retrospective observational study aimed to evaluate the intraoperative advantages and analgesic effects of preoperative UISB.

Patients and Methods

In this retrospective observational study, a total of 170 patients underwent shoulder arthroscopy at a tertiary medical center in southern Taiwan throughout 2019. After applying the exclusion criteria, 142 of these cases were included, with 74 and 68 in the UISB group and control groups, respectively. The primary outcome was the evaluation of intraoperative morphine milligram equivalent (MME) consumption. Secondary outcomes were sevoflurane consumption, the use of intraoperative antihypertensive drugs, and postoperative visual analog scale (VAS) scores in the post-anesthesia care unit (PACU) and in the ward at 24 h after surgery.

Results

Preoperative UISB effectively reduced opioids and volatile gases during surgery, supported by a 48.1% and 14.8% reduction in the median intraoperative MME and sevoflurane concentrations, respectively, and showed less need for antihypertensive drugs. The preoperative UISB group also showed significantly better performance on the VAS in both the PACU and ward.

Conclusion

Taken together, the preoperative UISB reduced not only intraoperative MME and sevoflurane consumption but also had satisfactory VAS scores in both the PACU and ward without any symptomatic respiratory complications. In summary, preoperative UISB is a reliable adjuvant analgesic technique and a key factor in achieving opioid-sparing and sevoflurane-sparing anesthesia and multimodal analgesia during shoulder arthroscopy.

Change in perioperative neutrophil-lymphocyte ratio as a potential predictive biomarker for chronic postsurgical pain and quality of life: an ambispective observational cohort study

Introduction

Accurate and accessible predictors of chronic postsurgical pain (CPSP) to identify high-risk postsurgical patients are prerequisite for preventive and interventional strategies. We investigated the incidence and risk factors of CPSP after abdominal surgery, with a focus on plasma immunological markers.

Materials and methods

This was a retrospective analysis of patients who underwent abdominal surgery under general anesthesia at a tertiary center between January 2021 and January 2022. The preoperative demographics, laboratory test data, and surgical factors of the participants were collected from the electronic medical record system. Postoperative pain intensity and living conditions at 1 year after discharge from the hospital were assessed via a phone survey. Univariate and multivariate analyses were used to explore independent risk factors associated with CPSP.

Results

A total of 968 patients were included, and 13.53% (n = 131 of 968) of patients reported CPSP 1 year after surgery. Patients with older age, open surgery, higher American Association of Anesthesiologists classification, patient-controlled intravenous analgesia application, longer surgery duration, higher postoperative absolute neutrophil count, and neutrophil-lymphocyte ratio (NLR), lower postoperative absolute lymphocyte count, and higher white blood cell count, were more likely to suffer from CPSP. A changed ratio of NLR (postoperative to preoperative) ≥ 5 significantly correlated with CPSP, moderate to severe pain, maximum numeric rating score since discharge from the hospital, and affected quality of life.

Discussion

The changed ratio of NLR could be used for the early identification of patients at risk for CPSP and affect the quality of life to alert the clinician to undertake further assessment.

Raising Awareness on the Clinical and Social Relevance of Adequate Chronic Pain Care

Appropriate pain care should be regarded as a right and effectively guaranteed to people with chronic pain (CP). Law 38, enacted in Italy in 2010, establishes the citizen's right not to suffer. Twelve years later, such right appears still disregarded in Italy and the current access to adequate pain care reveals significant shortcomings. In addition, a mismatch between CP-associated burden and the available healthcare resources in the framework of our national health system has been observed. This article gathers the perspectives of a Board of Italian anesthesiologists on the state of the art of CP management in Italy and aims at strengthening the scientific rationale and clinical relevance of pursuing the enforceability of the right not to suffer and at promoting widespread multidisciplinary care of patients with CP.

Chronic pain after surgery and trauma: current situation and future directions

Chronic post-surgical pain (CPSP) stands as a major health issue. The unchanged incidence over the last two decades underlines both the failure of predictive models developed until now and the lack of efficacy of common “preventive” strategies (pharmacotherapy and regional analgesic techniques) applied in current clinical practice. The recognition of CPSP as a disease and the release of a common definition of the condition is an important progress in the field. CPSP predictive scores exist but none has presently demonstrated an impact on patient care. New clinical directions based on the resolution of postoperative pain, a complex and highly dynamic process supported by individual pain trajectories, argue for predictive models and preventive strategies extended to the subacute pain period i.e. after hospital discharge.

Use of regional analgesia to prevent the conversion from acute to chronic pain

PURPOSE OF REVIEW

Chronic post-surgical pain (CPSP) prevalence has not changed over the past decades what questions the efficacy of preventive strategies. Regional analgesia is used to control acute pain, but preventive effect on CPSP remains debated. Failures and future application of regional analgesia to prevent transition from acute to chronic pain will be discussed.

RECENT FINDINGS

After thoracotomy, perioperative regional analgesia does not seem to prevent CPSP. After breast cancer surgery, paravertebral block might prevent CPSP intensity and impact on daily life up to 12 months, particularly in high catastrophizing patients. In knee arthroplasty, perioperative regional analgesia or preoperative genicular nerve neuroablation do not prevent CPSP, although current studies present several bias. The protective role of effective regional analgesia and early pain relief in trauma patients deserves further studies.

SUMMARY

Regional analgesia failure to prevent CPSP development should prompt us to reconsider its perioperative utilization. Patients' stratification, for example high-pain responders, might help to target those who will most benefit of regional analgesia. The impact of regional analgesia on secondary pain-related outcomes such as intensity and neuropathic character despite no difference on CPSP incidence requires more studies. Finally, the preventive effect of regional analgesia targeted interventions on CPSP in patients suffering from severe subacute pain deserves to be assessed.

Effects of Multimodal Analgesia Combined with Auricular Point Therapy on Physical and Mental Stress and Rehabilitation Quality of Patients with Meniscus Injury during the Perioperative Period

Objective

To investigate the effect of multimodal analgesia combined with auricular point therapy on physical and mental stress and rehabilitation quality of patients with meniscus injury during the perioperative period.

Methods

148 patients in our hospital from October 2019 to October 2021 who were scheduled to undergo meniscus surgery were selected and grouped according to the order of file establishment, with 74 cases in each. The control group was given routine analgesia, and the observation group was given multimodal analgesia combined with auricular point therapy. The pain level (visual analogue scale (VAS)), physical and mental stress (heart rate (HR), mean arterial pressure (MAP), depression scale (PHQ-9), and anxiety scale (GAD-7)), complications, rehabilitation quality, and analgesia satisfaction were observed.

Results

The VAS scores of pain in the observation group were lower than those in the control group at 6 hours before operation and at 6 hours, 24 hours, and 72 hours after operation (P < 0.05). The MAP, HR, PHQ-9, and GAD-7 scores of the observation group were lower than those of the control group 6 hours before operation (P < 0.05). There was no significant difference in MAP, HR, PHQ-9, and GAD-7 scores between the two groups at 6 hours and 24 hours after operation (P > 0.05). The analgesic satisfaction of the observation group was better than that of the control group (P < 0.05). The incidence of complications in the observation group was 8.11% compared with 12.16% in the control group, which was not statistically significant (P > 0.05). The first exhaust, getting out of bed, and hospital stay in the observation group were shorter than those in the control group (P < 0.05).

Conclusion

Multimodal analgesia combined with auricular acupuncture therapy is effective in perioperative patients with meniscus injury. It can reduce perioperative pain, reduce physical and mental stress, and promote early postoperative recovery through a variety of analgesic mechanisms.

Impact of varying degrees of peripheral nerve blockade on experimental pressure and ischemic pain: adductor canal and sciatic nerve blocks in a human model of compartment syndrome pain

INTRODUCTION

Early diagnosis of acute extremity compartment syndrome is crucial to timely surgical management. Pain is commonly used as an early diagnostic sign for acute extremity compartment syndrome, making regional anesthesia after lower extremity surgery controversial. This randomized study tested whether different concentrations of local anesthetics, or combinations of nerve blocks, would differentially impact the perception of acute extremity compartment syndrome-like pressure and ischemic pain.

METHODS

Healthy volunteers underwent quantitative sensory testing, including determination of pressure pain thresholds and prolonged pressure/ischemic pain in the leg using a variable cuff inflation system. Subjects were randomized to receive (1) adductor canal block alone (ACB), (2) ACB with low-concentration sciatic nerve block (ACB +LC SNB), or (3) ACB with high-concentration SNB (ACB +HC SNB). For the primary outcome, we assessed block-induced increases in pressure threshold to reach 6/10 pain, and compared the degree of increase between the three groups. The main secondary outcome was a comparison of average pain score during a 5 min hold at the 6/10 pressure pain threshold between the three groups.

RESULTS

All blocks raised pressure pain threshold and decreased ischemic pain, but to variable extents. Specifically, the amount the block increased pressure pain threshold was significantly different among ACB, ACB+LC SNB, and ACB+HC SNB groups (mean±SD: 24±32 mm Hg, 120±103 mm Hg, 159±93 mm Hg; p=0.002), with post hoc testing revealing ACB as less than the other two groups. Similarly, average pain scores during a prolonged/ischemic cuff hold differed among the groups (4.2±1.4, 1.4±1.7, 0.4±0.7; p<0.001), with post hoc testing revealing ACB as significantly higher.

DISCUSSION

This study suggests the possible utility of titrating regional anesthesia, to provide some analgesia while still allowing acute extremity compartment syndrome detection.

TRIAL REGISTRATION NUMBER

NCT04113954.

Individualized multidisciplinary analgesia to prevent persistent postsurgical pain

PURPOSE OF REVIEW

Persistent postsurgical pain as outcome of surgery has reached more attention in the past years. In the first place because of related disability, long-term use of (opioid)analgesics and impact on the quality of life of individual patients. In addition, the individual and societal socio-economic burden of PPSP is high and increasing in the light of increasing numbers of surgery world-wide.

RECENT FINDINGS

Actual studies identified risk factors for persistent postsurgical pain in relevant patient populations. Astonishingly, most of predicting factors seem unrelated to surgery.

SUMMARY

Future perioperative practice will have to focus on identifying patients at risk for PPSP before surgery and develop/offer suitable individually tailored preventive interventions.

Application of Ultrasound-Guided Transversus Abdominis Plane Block Combined with Nalbuphine Patient-Controlled Intravenous Analgesia in Postoperative Analgesia After Laparotomy: A Randomized Controlled Trial

Introduction

Pain is a common postoperative complication. The ideal postoperative analgesia is awake, safe, mobile, and without side effects. The objective of this study is to provide new ideas for postoperative analgesia by observing the safety and analgesic effect of different analgesic methods in patients undergoing laparotomy after surgery.

Methods

Patients, who underwent laparotomy between September 2019 and December 2020, were randomly divided into three groups: group S received sufentanil, group N received nalbuphine, group T + N received postoperative bilateral transversus abdominis plane block (TAPB) and nalbuphine. The primary outcomes included visual analog scale (VAS) score and the use of postoperative analgesic pump. Secondary outcomes included quality of life recovery (QoR-15) scale score and incidence of postoperative adverse reactions.

Results

Compared with group S and N, there were significant differences in the resting VAS score within 48 h after surgery, dynamic VAS score within 12 h after surgery, the first compression time, and cumulative use of patient-controlled intravenous analgesia (PCIA) drugs at 24 h in group T + N (P < 0.05). The QoR-15 score within 48 h after surgery in group T + N was significantly higher than group N (P < 0.05). The first exhaust time and the incidence of nausea and vomiting in group T + N were significantly lower than those in group N (P < 0.05).

Conclusions

Sufentanil PCIA and nalbuphine PCIA have equivalent analgesic effects, while TAPB combined with nalbuphine PCIA can ensure a good analgesic effect, thereby reducing the incidence of adverse reactions.