Rethinking the definition of chronic postsurgical pain: composites of patient-reported pain-related outcomes vs pain intensities alone

Multidimensional pain assessment and opioid use after total knee arthroplasty: continuous vs single-injection regional vs systemic analgesia

Introduction

Effective pain management after total knee arthroplasty (TKA) is essential for recovery. Continuous peripheral nerve blocks (PNBc) are often believed to provide superior pain relief compared with single-injection peripheral nerve blocks (PNBs). However, multidimensional pain-related patient-reported outcomes (PROs) have not been extensively studied.

Objective

Based on registry data, this study compared pain intensities summarized as a pain composite score (PCS) and postoperative opioid use between PNBc and PNBs nerve blocks in patients undergoing TKA, and evaluated additional PROs.

Methods

Data from 4,328 adults undergoing TKA enrolled in the PAIN OUT registry (ClinicalTrials.gov NCT02083835) were analyzed. Patients were categorized into general anesthesia (GA) or spinal anesthesia (SA), with subgroups general anesthesia only (GA-o) or spinal anesthesia only (SA-o), and combinations with single-injection PNB (GA&PNBs and SA&PNBs) or continuous PNB via catheter (GA&PNBc and SA&PNBc). The primary end point was PCS, summarizing pain intensities and time in severe pain during the first 24 hours. Secondary end points included opioid use and additional PROs.

Results

The use of GA&PNBc was associated with a higher PCS (+0.5 [0.0-0.9], P = 0.035) compared with GA&PNBs, while PCS was similar between SA&PNBs and SA&PNBc. Opioid use was more frequent in GA&PNBc (+20.3%) and SA&PNBc (+50.8%) compared with the respective PNBs groups (P < 0.001). Patient-reported outcomes were higher in PNBc groups (median score 3.2 vs 2.7-2.9 in other groups; P < 0.001).

Conclusion

Continuous PNBc showed no clear advantage over PNBs in pain relief, opioid use, or further PROs. Future research should incorporate comprehensive PROs to better evaluate analgesic techniques in TKA.

Chronic postsurgical pain in the ICD-11: implications for anaesthesiology and pain medicine

Chronic postsurgical pain (CPSP) is associated with reduced health-related quality of life and disability. In some patients, it can result in long-term opioid use even after minor surgery. Epidemiological studies have reported highly varying rates of CPSP, largely because researchers have used different definitions with self-defined cut-offs for pain scores. With the introduction of the 11th revision of the World Health Organisation International Classification of Diseases and Related Health Problems (ICD-11), chronic pain is now recognised as an entity of its own, its biopsychosocial nature is emphasised, and its definition is standardised. Compared with the ICD-11 definition, the prevalence of CPSP might have been overestimated in previous studies. The ICD-11 provides a multifactorial assessment of pain severity, referring to pain intensity, pain-related interference, and pain-related distress, which cover the biopsychosocial aspects of chronic pain. These three scores can be added as extension codes to any pain diagnosis. Harmonisation of the CPSP criteria within the different coding levels of the ICD-11 might improve discrimination of CPSP from other chronic pain conditions not induced by surgery. Although neuropathic CPSP increases pain severity and requires alternative therapeutic approaches to nociceptive pain, a specific code to differentiate between neuropathic and non-neuropathic CPSP is not available. For clinical practice and research, the evidence-based ICD-11 definition, which provides clear-cut diagnostic criteria, should generally be used instead of pain scores alone. This will improve the comparability of data, form the basis for future diagnostic and therapeutic approaches, and facilitate communication.

Development and internal validation of a clinical risk tool to predict chronic postsurgical pain in adults: a prospective multicentre cohort study

ABSTRACT

Chronic postsurgical pain (CPSP) is a highly prevalent condition. To improve CPSP management, we aimed to develop and internally validate generalizable point-of-care risk tools for preoperative and postoperative prediction of CPSP 3 months after surgery. A multicentre, prospective, cohort study in adult patients undergoing elective surgery was conducted between May 2021 and May 2023. Prediction models were developed for the primary outcome according to the International Association for the Study of Pain criteria and a secondary threshold-based CPSP outcome. Models were developed with multivariable logistic regression and backward stepwise selection. Internal validation was conducted using bootstrap resampling, and optimism was corrected by shrinkage of predictor weights. Model performance was assessed by discrimination and calibration. Clinical utility was assessed by decision curve analysis. The final cohort included 960 patients, 16.3% experienced CPSP according to the primary outcome and 33.6% according to the secondary outcome. The primary CPSP model included age and presence of other preoperative pain. Predictors in the threshold-based models associated with an increased risk of CPSP included younger age, female sex, preoperative pain in the surgical area, other preoperative pain, orthopedic surgery, minimally invasive surgery, expected surgery duration, and acute postsurgical pain intensity. Optimism-corrected area-under-the-receiver-operating curves for preoperative and postoperative threshold-based models were 0.748 and 0.747, respectively. These models demonstrated good calibration and clinical utility. The primary CPSP model demonstrated fair predictive performance including 2 significant predictors. Derivation of a generalizable risk tool with point-of-care predictors was possible for the threshold-based CPSP models but requires independent validation.

Factors associated with poor pain experience after surgery

OBJECTIVE

To identify factors associated with poor postoperative pain experience by examining patient-related and procedural variables.

METHODS

An exploratory secondary analysis was conducted on data from 971 adult patients undergoing elective surgery under general anesthesia across five French teaching hospitals. Preoperative anxiety was assessed using the Amsterdam Preoperative Anxiety and Information Scale (APAIS). Pain, sleep quality and well-being were measured preoperatively and postoperatively using visual analog scales (VAS). The primary endpoint was the patient experience measured by the Evaluation du Vécu de l'Anesthésie Generale (EVAN-G) questionnaire on postoperative day 1, with poor pain experience defined as a score below the 25th percentile on the EVAN-G pain dimension. Univariate and multivariate logistic regression analyses were performed to identify factors associated with poor pain experience.

RESULTS

Poor pain experience was reported by 271 patients (27.9%). Multivariate analysis identified intraoperative use of remifentanil and sufentanil as an independent predictor of poor pain experience with an OR of 26.96 (95% CI 2.17 to 334.23, p=0.01). Additionally, age (OR 0.97, p=0.003), absence of premedication (OR 0.49, p=0.035) and orthopedic surgery (OR 0.29, p=0.005) were associated with a lower likelihood of poor pain experience. Conversely, American Society of Anesthesiologists (ASA) 3 status (OR 5.09, p=0.028), postoperative anxiolytic use (OR 8.20, p<0.001), amnesia (OR 1.58, p=0.001), higher VAS pain (p<0.001) and lower well-being scores (p=0.007) on day 1 were predictors of poor pain experience.

CONCLUSION

The intraoperative use of remifentanil and sufentanil is independently associated with poorer postoperative pain experience. These findings highlight the need to reassess intraoperative analgesic strategies to enhance patient outcomes and reduce postoperative complications.

Chronic postsurgical pain and transitional pain services: a narrative review highlighting European perspectives

BACKGROUND/IMPORTANCE

Chronic postsurgical pain (CPSP) is a significant, often debilitating outcome of surgery, impacting patients' quality of life and placing a substantial burden on healthcare systems worldwide. CPSP (pain persisting for more than 3 months postsurgery) leads to both physical and psychological distress. Recognized as a distinct chronic pain entity in International Classification of Diseases, 11th Revision, CPSP enables better reporting and improved management strategies. Despite advancements in surgical care, CPSP remains prevalent, affecting 5%-85% of patients, with higher rates following thoracotomies, amputations, mastectomies and joint replacements.

OBJECTIVE

The acute to chronic pain transition involves complex interactions between peripheral and central mechanisms, with central sensitization playing a key role. Identifying high-risk patients is crucial for prevention, with factors such as surgical type, nerve injury, neuropathic elements in acute postoperative pain, and psychosocial conditions being significant contributors.

EVIDENCE REVIEW

Current pain management strategies, including multimodal therapy and regional anesthesia, show limited effectiveness in preventing CPSP. Neuromodulation interventions, though promising, are not yet established as preventive modalities.

FINDINGS

Transitional pain services (TPSs) offer a comprehensive, multidisciplinary approach to managing CPSP and reducing opioid dependence, addressing both physical and psychosocial aspects of functional recovery. While promising results have been seen in Canada and Finland, TPSs are not yet widely implemented in Europe. There is also growing interest in pain biomarkers, through initiatives such as the A2CPS program, aiming to improve CPSP prediction and develop targeted interventions.

CONCLUSIONS

Future research should focus on large-scale studies integrating various factors to facilitate CPSP prediction, refine prevention strategies and reduce its long-term impact.

Recognizing pain phenotypes: biopsychosocial sources of variability in the transition to chronic postsurgical pain

Chronic postsurgical pain (CPSP) is a cause of new chronic pain, with a wide range of reported incidence. Previous longitudinal studies suggest that development of CPSP may depend more on the constellation of risk factors around a patient (pre-existing pain phenotype) rather than on the extent of surgical injury itself. The biopsychosocial model of pain outlines a broad array of factors that modulate the severity, longevity, and impact of pain. Biological variables associated with CPSP include age, sex, baseline pain sensitivity, and opioid tolerance. Psychological factors, including anxiety, depression, somatization, sleep disturbance, catastrophizing, and resilience, and social factors, like education and social support, may also importantly modulate CPSP. Prevention efforts have targeted acute pain reduction using multimodal analgesia (regional anesthesia and intraoperative analgesic adjuvant medications). However, studies that do not measure or take phenotypic risk factors into account (either using them for enrichment or statistically as effect modifiers) likely suffer from underpowering, and thus, fail to discern subgroups of patients that preventive measures may be most helpful to. Early preoperative identification of a patient's pain phenotype allows estimation of their constellation of risk factors and may greatly enhance successful, personalized prevention of postoperative pain. Effective preoperative employment of behavioral interventions like cognitive-behavioral therapy, stress reduction, and physical and mental prehabilitation may particularly require knowledge of a patient's pain phenotype. Preoperative assessment of patients' pain phenotypes will not only inform high-quality personalized perioperative care clinically, but it will enable enriched testing of novel therapies in future scientific studies.

Prevalence of and recommendation for measuring chronic postsurgical pain in children: an updated systematic review and meta-analysis

BACKGROUND

According to the prior 2017 review (Rabbitts et al), approximately 20% of children and adolescents develop chronic postsurgical pain (CPSP; ie, pain persisting >3 months after surgery) after major surgeries, which is associated with adverse functional and psychological consequences. A major barrier was that definitions of CPSP applied were highly variable. Since that prior review was conducted (n=4 studies in meta-analysis), numerous relevant studies have been published warranting an update.

OBJECTIVE

The aims of this current review were to: (1) provide an updated prevalence estimate for pediatric CPSP and (2) examine definitions of pediatric CPSP applied in current research.

EVIDENCE REVIEW

Prospective, observational studies examining CPSP using a validated self-report pain intensity measure in children were included. 4884 unique publications were screened with 20 articles meeting inclusion criteria. Risk of bias using Quality in Prognostic Study tool ranged from low to high.

FINDINGS

The pooled prevalence of CPSP among mostly major surgeries was 28.2% (95% CI 21.4% to 36.1%). Subgroup analysis of spinal fusion surgeries identified a prevalence of 31% (95% CI 21.4% to 43.5%). Using Grading of Recommendations, Assessment, Development, and Evaluation, the certainty in prevalence estimates was moderate. Studies used a range of valid pain intensity measures to classify CPSP (eg, Numeric Rating Scale), often without pain interference or quality of life measures.

CONCLUSIONS

The overall prevalence of pediatric CPSP is higher than estimated in the prior review, and quality of studies generally improved though with some heterogeneity. Standardizing the measurement of CPSP will facilitate future efforts to combine and compare data across studies.

PROSPERO REGISTRATION NUMBER

CRD42022306340.

[Structure and process evaluation of complex interventions in pain therapy : Description of a methodological approach using the example of POET-Pain]

To evaluate the quality of care, particularly in the case of new forms of healthcare interventions, the healthcare services to be provided are defined and documented in advance. The presented explanatory sequential mixed methods design combines quantitative and qualitative data collection and the analysis enables a deeper understanding of a new healthcare intervention. Using the example of the POET-Pain project, which investigates the effect of a perioperative transitional pain service (TPS), the methodological application of the explanatory sequential mixed methods design is demonstrated in order to present the structural and process evaluation of the new healthcare intervention (in this case TPS) and to understand its influence on the quality of care. The mixed methods design presented enables the results of the quantitative phase to be interpreted and expanded in depth using qualitative data, which leads to a comprehensive understanding of the subject matter (second pillar of health services research).

Chronic pain after cesarean delivery: what do we know today? A narrative review

Childbirth is a major event in life, associated with both physical and psychological changes which may affect women's quality of life. Cesarean delivery (CD) is among the most frequent surgical procedures performed worldwide. Because of the high CD volume and patients' vulnerability (young age and female sex), for chronic postsurgical pain (CPSP), the societal impact of chronic pain after CD requires attention. According to the literature, the incidence of CPSP after CD is highly variable but reasonable evidence suggests a low incidence at six months (3-4%) and later (0.6-0.8%). The recent definition of CPSP in the ICD-11 coding system may not necessarily apply to the specific context of childbirth and CPSP after CD, suggesting that some modifications could be implemented. Interestingly, the incidence of chronic pain after CD is lower than that observed after gynecologic procedures performed in the similar body area. Consequently, since the risk factors do not really differ from those reported for other procedures, the existence of protective factors related to hormonal modulations secondary to pregnancy and lactation have been suggested. Such observations, in preclinical models, also question the pathophysiology of chronic pain after childbirth. Because severe acute postpartum pain is a striking risk factor of CPSP after CD, the preventive effect of different analgesic treatments, mainly regional analgesia techniques, has been evaluated but the results remain disappointing. In conclusion, many questions remain regarding the incidence, pathophysiology and potential prevention of CPSP after CD, and these questions warrant further research.

Presurgical anxiety and acute postsurgical pain predict worse chronic pain profiles after total knee/hip arthroplasty

INTRODUCTION

Total joint arthroplasties generally achieve good outcomes, but chronic pain and disability are a significant burden after these interventions. Acknowledging relevant risk factors can inform preventive strategies. This study aimed to identify chronic pain profiles 6 months after arthroplasty using the ICD-11 (International Classification of Diseases) classification and to find pre and postsurgical predictors of these profiles.

MATERIALS AND METHODS

Patients undergoing total knee/hip arthroplasty (n = 209, female = 54.5%) were assessed before surgery, 48 h and 6 months postsurgery for sociodemographic, pain-related, disability and psychological characteristics. K-means-constrained cluster analysis identified chronic pain profiles based on 6-month pain intensity, pain interference and disability. Chi-square tests or one-way ANOVA explored between-cluster differences. Multinomial regression identified predictors of cluster membership. Separate models analyzed presurgical (model 1), postsurgical (model 2) and a combination of previously significant pre and postsurgical (model 3) variables.

RESULTS

A three-cluster solution was selected, translating increasingly worse chronic pain severity: cluster 1 (C1, n = 129), cluster 2 (C2, n = 60) and cluster 3 (C3, n = 20). There were presurgical differences among clusters in the presence of other painful sites (p = 0.013, ϕc = 0.20), pain interference (p = 0.038, η2 = 0.031), disability (p = 0.020, η2 = 0.037), pain catastrophizing (p = 0.019, η2 = 0.060), anxiety (p < 0.001, η2 = 0.087), depression (p = 0.017; η2 = 0.039), self-efficacy (p = 0.018, η2 = 0.038) and satisfaction with life (p = 0.034, η2 = 0.032), postsurgical pain frequency (p = 0.003, ϕc = 0.243) and intensity (p < 0.001, η2 = 0.101). In model 1, disability predicted C2 (OR = 1.040) and anxiety predicted C3 (OR = 1.154) membership. In model 2, pain intensity predicted C3 (OR = 1.690) membership. In model 3, presurgical anxiety predicted C3 (OR = 1.181) and postsurgical pain intensity predicted C2 (OR = 1.234) and C3 (OR = 1.679) membership.

CONCLUSIONS

Most patients had low chronic pain severity at 6 months, but a relevant percentage exhibited poor outcomes. Membership to different outcome profiles was predicted by presurgical anxiety and acute postsurgical pain. These seem promising targets to prevent pain chronification that should be optimized for better surgical outcomes.

Incidence and risk factors for chronic pain following primary total knee arthroplasty in an irish surgical population

OBJECTIVES

To identify the incidence and characteristics of chronic post-surgical pain (CPSP) following total knee arthroplasty and determine peri-operative influencing factors.

METHODS

A representative, retrospective random sample was taken of patients who underwent total knee arthroplasty in the South Infirmary University Hospital Cork for an 18-month period. Two hundred fourteen patient charts were reviewed out of a total of 507 charts for that period to provide a 90% confidence interval.

RESULTS

The incidence of CPSP in an Irish population 6 months after total knee arthroplasty was found to be 36.5%. The following factors were found to be statistically significant with respect to the incidence of CPSP: female sex, lack of multimodal analgesia (consisting of paracetamol, NSAID, and opioids), general anaesthesia, and lower Oxford Knee Scores at 6 months post-surgery. Age, the knee operated on, ASA grade, or greatest acuity pain, were not found to be statistically significant factors in the development of CPSP.

CONCLUSIONS

CPSP is common after total knee arthroplasty with an incidence of 36.5% at 6 months post procedure. Female sex, lack of multimodal analgesia, and lower Oxford Knee Scores were associated with increased CPSP.

From pain level to pain experience: redefining acute pain assessment to enhance understanding of chronic postsurgical pain

BACKGROUND

Chronic postsurgical pain (CPSP) significantly impairs quality of life and poses a substantial healthcare burden, affecting up to a quarter of patients undergoing surgery. Although acute pain is recognised as a predictor for CPSP development, the role of patient experience remains underexplored. This study examines the predictive value of patient experience alongside traditional risk factors for CPSP after orthopaedic surgery.

METHODS

An exploratory analysis was conducted on 294 patients from a multicentre randomised clinical trial comparing continuous perineural analgesia and single-injection nerve block in ambulatory orthopaedic surgeries. Patient experience was assessed using the Evaluation du Vecu de l'Anesthésie Générale (EVAN-G) validated questionnaire. Factors associated with CPSP at 90 days after surgery were identified through univariate and multivariate analyses, incorporating patient-reported outcomes and classical variables.

RESULTS

Out of 219 patients with complete data, 63 (29%) developed CPSP at day 90. Multivariate analysis revealed a poor pain experience, as assessed by the pain dimension of EVAN-G on postoperative day 2, as an independent predictor of CPSP (odds ratio 6.45, 95% confidence interval 1.65-25.26, P<0.01). Poor pain experience was associated with an augmented risk of CPSP.

CONCLUSIONS

This study underscores the role of patient-reported outcomes, specifically the pain experience dimension captured by the EVAN-G scale, in prediction of CPSP 90 days after surgery. It suggests a shift from conventional assessments of pain intensity to a comprehensive understanding of pain experience, advocating for tailored pain management approaches that could reduce chronic pain, thereby improving patient quality of life and functional recovery.

Understanding the Multifactorial Influences on Postsurgical Pain After Rotator Cuff Repair: A Retrospective Cohort Study

Background

The experience of chronic postsurgical pain (CPSP) can vary widely among patients after rotator cuff repair (RCR).

Purpose

To determine the prevalence and predictive factors of CPSP at 6 months after RCR.

Study Design

Cohort study; Level of evidence, 3.

Methods

The following assessments were conducted preoperatively and 6 months postoperatively in adult patients with RCR who had undergone primary arthroscopic RCR (N = 1987): Constant score, pain assessed on the numeric rating scale (0-10), the Subjective Shoulder Value, the Oxford Shoulder Score, and quality of life as measured by the EuroQol-5 Dimensions-5 Level (EQ-5D-5L). Patient characteristics-including age, sex, body mass index, and smoking status-and surgical factors-including the duration of surgery and the American Society of Anesthesiologists (ASA) classification-were also reported. Multivariate logistic regression analysis was performed to determine which variables were predictors for CPSP.

Results

The prevalence of moderate to severe preoperative pain in the patients was 30.4% for CPSP. After adjusting for age, surgery duration, ASA classification, sex, and body mass index, results revealed that unique predictors for CPSP were as follows: (1) the presence of preoperative negative affect-assessed using the anxiety/depression dimension of the EQ-5D-5L (odds ratio [OR], 1.46 (P < .001); (2) preoperative pain (OR, 1.17; P < .001); and (3) shoulder function (OR, 0.96; P < .001). None of the surgical factors appeared to predict CPSP.

Conclusion

Patients predisposed to CPSP can be identified during the preoperative phase. Collectively, there is a call for a more in-depth assessment of biopsychosocial risk factors that could substantially influence the postoperative pain experience.

Current concepts and targets for preventing the transition of acute to chronic postsurgical pain

PURPOSE OF REVIEW

It is estimated that approximately a third of patients undergoing certain surgeries may report some degree of persistent pain postoperatively. Chronic postsurgical pain (CPSP) reduces quality of life, is challenging to treat, and has significant socio-economic impact.

RECENT FINDINGS

From an epidemiological perspective, factors that predispose patients to the development of CPSP may be considered in relation to the patient, the procedure or, the care environment. Prevention or management of transition from acute to chronic pain often need a multidisciplinary approach beginning early in the preoperative period and continuing beyond surgical admission. The current concepts regarding the role of central and peripheral nervous systems in chronification of pain may provide targets for future therapies but, the current evidence seems to suggest that a multimodal analgesic approach of preventive analgesia along with a continued follow-up and treatment after hospital discharge may hold the key to identify and manage the transitioning of acute to chronic pain.

SUMMARY

A comprehensive multidisciplinary approach with prior identification of risk factors, minimizing the surgical insult and a culture of utilizing multimodal analgesia and continued surveillance beyond the period of hospitalization is an important step towards reducing the development of chronic pain. A transitional pain service model may accomplish many of these goals.

Advancements in Modern Treatment Approaches for Central Post-Stroke Pain: A Narrative Review

PURPOSE OF REVIEW

Central post-stroke pain (CPSP) poses a multifaceted challenge in medical practice, necessitating a thorough and multidisciplinary approach for its diagnosis and treatment. This review examines current methods for addressing CPSP, highlighting both pharmacological and non-pharmacological therapies. It covers the mechanisms and clinical effectiveness of these treatments in managing CPSP and emphasizes the importance of personalized treatment plans, given the varied causes of CPSP.

RECENT FINDINGS

Recent advancements have illuminated diverse treatment modalities for CPSP. Pharmacotherapy spans from conventional analgesics to anticonvulsants and antidepressants, tailored to mitigate the neuropathic characteristics of CPSP. Non-pharmacological interventions, including physical therapy and psychological strategies, are pivotal in managing CPSP's chronic nature. For cases resistant to standard treatments, advanced interventions such as nerve blocks and surgical procedures like deep brain stimulation (DBS) or motor cortex stimulation (MCS) are considered. Additionally, innovative technologies such as neuromodulation techniques and personalized medicine are emerging as promising avenues to enhance therapeutic outcomes and improve quality of life for individuals grappling with CPSP.

SUMMARY

Modern approaches in managing CPSP require an interdisciplinary and patient-centric approach. Customizing treatment plans to address the specific etiology and symptoms of CPSP is crucial. Pharmacotherapy remains fundamental, encompassing medications such as anticonvulsants and antidepressants tailored to manage neuropathic pain. Integrating non-pharmacological interventions is crucial for providing comprehensive care. Additionally, investigating innovative technologies and personalized medicine presents promising opportunities to enhance treatment results and elevate the quality of life for those suffering from CPSP. Ultimately, an integrated approach that acknowledges the multifaceted nature of CPSP is essential for effective management and patient well-being.

Perioperative Risk Factors for Persistent Postsurgical Pain After Inguinal Hernia Repair: Systematic Review and Meta-Analysis

Persistent postsurgical pain (PPSP) is one of the most bothersome and disabling long-term complications after inguinal hernia repair surgery. Understanding perioperative risk factors that contribute to PPSP can help identify high-risk patients and develop risk-mitigation approaches. The objective of this study was to systematically review and meta-analyze risk factors that contribute to PPSP after inguinal hernia repair. The literature search resulted in 303 papers included in this review, 140 of which were used for meta-analyses. Our results suggest that younger age, female sex, preoperative pain, recurrent hernia, postoperative complications, and postoperative pain are associated with a higher risk of PPSP. Laparoscopic techniques reduce the PPSP occurrence compared to anterior techniques such as Lichtenstein repair, and tissue-suture techniques such as Shouldice repair. The use of fibrin glue for mesh fixation was consistently associated with lower PPSP rates compared to tacks, staples, and sutures. Considerable variability was observed with PPSP assessment and reporting methodology in terms of study design, follow-up timing, clarity of pain definition, as well as pain intensity or interference threshold. High or moderate risk of bias in at least one domain was noted in >75% of studies. These may limit the generalizability of our results. Future studies should assess and report comprehensive preoperative and perioperative risk factors for PPSP adjusted for confounding factors, and develop risk-prediction models to drive stratified PPSP-mitigation trials and personalized clinical decision-making. PERSPECTIVE: This systematic review and meta-analysis summarizes the current evidence on risk factors for persistent pain after inguinal hernia repair. The findings can help identify patients at risk and test personalized risk-mitigation approaches to prevent pain. PROSPERO REGISTRATION: htttps://www.crd.york.ac.uk/prospero/display_record.php?RecordID=154663.

Understanding Kinesiophobia: Predictors and Influence on Early Functional Outcomes in Patients with Total Knee Arthroplasty

This observational study aimed to identify predictors of kinesiophobia and examine its correlation with early functional outcomes in TKA recipients. On the first and fifth postoperative days (POD1 and POD5), we evaluated pain using the International Pain Outcomes Questionnaire (IPO-Q) and created multidimensional pain composite scores (PCSs). The Total Pain Composite Score (PCStotal) assesses the overall impact of pain, taking into account outcomes of pain intensity, pain-related interference with function, and emotions and side effects. Functional status on POD 5 was determined by the Barthel index, 6 min walking test, and knee range of motion. Kinesiophobia was assessed on POD5 using the Tampa Scale for Kinesiophobia (TSK). Among 75 TKA patients, 27% exhibited kinesiophobia. The final regression model highlighted PCStotal on POD5 (OR = 6.2, CI = 1.9-19.9), PCStotal (OR = 2.1, CI = 1.2-3.8) on POD1, and the intensity of chronic pain before surgery (OR = 1.4, CI = 1.1-2.1) as significant kinesiophobia predictors. On POD5, those with kinesiophobia showed increased dependency, slower gait, and poorer knee extension recovery. This study emphasizes the need to identify and address kinesiophobia in TKA patients for better functional outcomes and recovery. Additionally, it is vital to assess different domains of pain, not just pain intensity, as it can lead to kinesiophobia development.

[Preoperative evaluation of adult patients before elective, non-cardiothoracic surgery : A joint recommendation of the German Society for Anesthesiology and Intensive Care Medicine, the German Society for Surgery and the German Society for Internal Medicine]

The 70 recommendations summarize the current status of preoperative risk evaluation of adult patients prior to elective non-cardiothoracic surgery. Based on the joint publications of the German scientific societies for anesthesiology and intensive care medicine (DGAI), surgery (DGCH), and internal medicine (DGIM), which were first published in 2010 and updated in 2017, as well as the European guideline on preoperative cardiac risk evaluation published in 2022, a comprehensive re-evaluation of the recommendation takes place, taking into account new findings, the current literature, and current guidelines of international professional societies. The revised multidisciplinary recommendation is intended to facilitate a structured and common approach to the preoperative evaluation of patients. The aim is to ensure individualized preparation for the patient prior to surgery and thus to increase patient safety. Taking into account intervention- and patient-specific factors, which are indispensable in the preoperative risk evaluation, the perioperative risk for the patient should be minimized and safety increased. The recommendations for action are summarized under "General Principles (A)," "Advanced Diagnostics (B)," and the "Preoperative Management of Continuous Medication (C)." For the first time, a rating of the individual measures with regard to their clinical relevance has been given in the present recommendation. A joint and transparent agreement is intended to ensure a high level of patient orientation while avoiding unnecessary preliminary examinations, to shorten preoperative examination procedures, and ultimately to save costs. The joint recommendation of DGAI, DGCH and DGIM reflects the current state of knowledge as well as the opinion of experts. The recommendation does not replace the individualized decision between patient and physician about the best preoperative strategy and treatment.

Chronic postsurgical pain: A European survey

BACKGROUND

Chronic postsurgical pain (CPSP) is a clinical problem, and large prospective studies are needed to determine its incidence, characteristics, and risk factors.

OBJECTIVE

To find predictive factors for CPSP in an international survey.

DESIGN

Observational study.

SETTING

Multicentre European prospective observational trial.

PATIENTS

Patients undergoing breast cancer surgery, sternotomy, endometriosis surgery, or total knee arthroplasty (TKA).

METHOD

Standardised questionnaires were completed by the patients at 1, 3, and 7 days, and at 1, 3, and 6 months after surgery, with follow-up via E-mail, telephone, or interview.

MAIN OUTCOME MEASURE

The primary goal of NIT-1 was to propose a scoring system to predict those patient likely to have CPSP at 6 months after surgery.

RESULTS

A total of 3297 patients were included from 18 hospitals across Europe and 2494 patients were followed-up for 6 months. The mean incidence of CPSP at 6 months was 10.5%, with variations depending on the type of surgery: sternotomy 6.9%, breast surgery 7.4%, TKA 12.9%, endometriosis 16.2%. At 6 months, neuropathic characteristics were frequent for all types of surgery: sternotomy 33.3%, breast surgery 67.6%, TKA 42.4%, endometriosis 41.4%. One-third of patients experienced CPSP at both 3 and 6 months. Pre-operative pain was frequent for TKA (leg pain) and endometriosis (abdomen) and its frequency and intensity were reduced after surgery. Severe CPSP and a neuropathic pain component decreased psychological and functional wellbeing as well as quality of life. No overarching CPSP risk factors were identified.

CONCLUSION

Unfortunately, our findings do not offer a new CPSP predictive score. However, we present reliable new data on the incidence, characteristics, and consequences of CPSP from a large European survey. Interesting new data on the time course of CPSP, its neuropathic pain component, and CPSP after endometriosis surgery generate new hypotheses but need to be confirmed by further research.

TRIAL REGISTRATION

clinicaltrials.gov ID: NCT03834922.

Efficacy and safety of perioperative ketamine for the prevention of chronic postsurgical pain: A meta-analysis

STUDY OBJECTIVE

Assessment of the efficacy and safety of perioperative intravenous ketamine in reducing incidence and severity of chronic postsurgical pain.

STUDY DESIGN

A systematic review and meta-analysis of randomized controlled trials (RCTs).

DATA SOURCES

The following data sources were systematically searched: MEDLINE, CENTRAL, and EMBASE (till 02/2021).

PATIENTS

Adult patients undergoing any surgery.

INTERVENTIONS

Perioperative use of intravenous ketamine as an additive analgesic drug compared to placebo, no active control treatment, and other additive drugs.

MEASUREMENTS

Primary outcomes were number of patients with chronic postsurgical pain after 6 months and ketamine related adverse effects. Secondary outcomes were chronic postsurgical pain incidence after 3 and 12 months, chronic postsurgical neuropathic pain incidence, chronic postsurgical moderate to severe pain incidence, intensity of chronic postsurgical pain at rest, and during movement, oral morphine consumption after 3, 6, and 12 months and incidence of opioid-related adverse effects.

MAIN RESULTS

Thirty-six RCTs were included with a total of 3572 patients. Ketamine compared to placebo may result in no difference in the number of patients with chronic postsurgical pain after 6 months (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.71-1.05; I2  = 34%; 16 studies; low-certainty evidence). Ketamine may reduce the incidence of chronic postsurgical neuropathic pain after 3 months in comparison to placebo (RR 0.78, 95% CI 0.62-0.99, I2  = 31%, seven trials, low-certainty evidence). Ketamine compared to placebo may increase the risk for postoperative nystagmus (RR 9.04, 95% CI 1.15-70.90, I2 30%, two trials, low-certainty evidence) and postoperative visual disturbances (RR 2.29, 95% CI 1.05-4.99, I2 10%, seven trials, low-certainty evidence).

CONCLUSIONS

There is low-certainty evidence that perioperative ketamine has no effect on chronic postsurgical pain in adult patients. Low-certainty evidence suggests that ketamine compared to placebo may reduce incidence of chronic postsurgical neuropathic pain after 3 months. Questions like ideal dosing, treatment duration and more patient-related outcome measures remain unanswered, which warrants further studies.

PROTOCOL REGISTRATION

Prospero CRD42021223625, 07.01.2021.

Trajectories of pain and opioid use up to one year after surgery: analysis of a European registry

BACKGROUND

Long-term opioid use after surgery is a crucial healthcare problem in North America. Data from European hospitals are scarce and differentiation of chronic pain has rarely been considered.

METHODS

In a mixed surgical cohort of the PAIN OUT registry, opioid use and chronic pain were evaluated before surgery, and 6 and 12 months after surgery (M6/M12). Subgroups with or without opioid medication and pre-existing chronic pain were analysed. M12-chronic pain was categorised as chronic postsurgical pain (CPSP) meeting the ICD-11 definition, chronic pain related to surgery not meeting the ICD-11 definition, and chronic pain unrelated to surgery. Primary endpoint was the rate of M12 opioid users. Variables associated with M12 opioid use and patient-reported outcomes were evaluated.

RESULTS

Of 2326 patients, 5.5% were preoperative opioid users; 4.4% and 3.5% took opioids at M6 and M12 (P<0.001). Chronic pain before operation and at M6/M12 was reported by 41.2%, 41.8%, and 34.7% of patients, respectively (P<0.001). The rate of M12 opioid users was highest in group unrelated (22.3%; related 8.3%, CPSP 1.5%; P<0.001). New opioid users were 1.1% (unrelated 7.1%, related 2.3%, CPSP 0.7%; P<0.001). M12 opioid users reported more pain, pain-related physical and affective interference, and needed more opioids than non-users. The predominant variable associated with M12 opioids was preoperative opioid use (estimated odds ratio [95% confidence interval]: 28.3 [14.1-56.7], P<0.001).

CONCLUSIONS

Opioid use was low in patients with CPSP, and more problematic in patients with chronic pain unrelated to surgery. A detailed assessment of chronic pain unrelated or related to surgery or CPSP is necessary.

CLINICAL TRIAL REGISTRATION

NCT02083835.

Postoperative Analgesics Score as a Predictor of Chronic Postoperative Inguinal Pain After Inguinal Hernia Repair: Lessons Learned From a Retrospective Analysis

BACKGROUND

Chronic postoperative inguinal pain (CPIP) is a common complication after inguinal hernia surgery and occurs in up to 10-14% of cases. CPIP has a significant impact on daily life, work ability and thus compromises quality of life. The aim of this retrospective study was an in-depth analysis of patients undergoing inguinal hernia repair to further refine the prediction of the onset of CPIP reliably.

METHODS

A single center retrospective analysis of patients with who underwent open or minimally invasive inguinal hernia repair from 2016 to 2021 was carried out. Complication rates, detailed analysis of postoperative pain medication and quality of life using the EuraHS Quality of Life questionnaire were assessed.

RESULTS

Out of 596 consecutive procedures, 344 patients were included in detailed analyses. While patient cohorts were different in terms of age and co-morbidities, and the prevalence of CPIP was 12.2% without differences between the surgical procedures (Lichtenstein: 12.8%; TEP 10.9%; TAPP 13.5%). Postoperative pain was evaluated using a newly developed analgesic score. Patients who developed CPIP later had a significant higher consumption of analgesics at discharge (p = 0.016). As additional risk factors for CPIP younger patient age and postoperative complications were identified.

CONCLUSION

The prospective use of the analgesic score established here could be helpful to identify patients that are at risk to develop CPIP. These patients could benefit from a structured follow-up to allow early therapeutic intervention to prevent chronification and restore the quality of life.

The mechanisms and management of persistent postsurgical pain

An estimated 10%-50% of patients undergoing a surgical intervention will develop persistent postsurgical pain (PPP) lasting more than 3 months despite adequate acute pain management and the availability of minimally invasive procedures. The link between early and late pain outcomes for surgical procedures remains unclear-some patients improve while others develop persistent pain. The elective nature of a surgical procedure offers a unique opportunity for prophylactic or early intervention to prevent the development of PPP and improve our understanding of its associated risk factors, such as pre-operative anxiety and the duration of severe acute postoperative pain. Current perioperative pain management strategies often include opioids, but long-term consumption can lead to tolerance, addiction, opioid-induced hyperalgesia, and death. Pre-clinical models provide the opportunity to dissect mechanisms underpinning the transition from acute to chronic, or persistent, postsurgical pain. This review highlights putative mechanisms of PPP, including sensitisation of peripheral sensory neurons, neuroplasticity in the central nervous system and nociceptive signalling along the neuro-immune axis.

Shared Decision-Making in Acute Pain Services

PURPOSE OF REVIEW

The implementation of shared decision-making (SDM) in acute pain services (APS) is still in its infancies especially when compared to other medical fields.

RECENT FINDINGS

Emerging evidence fosters the value of SDM in various acute care settings. We provide an overview of general SDM practices and possible advantages of incorporating such concepts in APS, point out barriers to SDM in this setting, present common patient decisions aids developed for APS and discuss opportunities for further development. Especially in the APS setting, patient-centred care is a key component for optimal patient outcome. SDM could be included into everyday clinical practice by using structured approaches such as the "seek, help, assess, reach, evaluate" (SHARE) approach, the 3 "MAking Good decisions In Collaboration"(MAGIC) questions, the "Benefits, Risks, Alternatives and doing Nothing"(BRAN) tool or the "the multifocal approach to sharing in shared decision-making"(MAPPIN'SDM) as guidance for participatory decision-making. Such tools aid in the development of a patient-clinician relationship beyond discharge after immediate relief of acute pain has been accomplished. Research addressing patient decision aids and their impact on patient-reported outcomes regarding shared decision-making, organizational barriers and new developments such as remote shared decision-making is needed to advance participatory decision-making in acute pain services.

Following Evidence-Based Recommendations for Perioperative Pain Management after Cesarean Section Is Associated with Better Pain-Related Outcomes: Analysis of Registry Data

Women who have had a Cesarean Section (CS) frequently report severe pain and pain-related interference. One reason for insufficient pain treatment might be inconsistent implementation of evidence-based guidelines. We assessed the association between implementing three elements of care recommended by guidelines for postoperative pain management and pain-related patient-reported outcomes (PROs) in women after CS. The analysis relied on an anonymized dataset of women undergoing CS, retrieved from PAIN OUT. PAIN OUT, an international perioperative pain registry, provides clinicians with treatment assessment methodology and tools for patients to assess multi-dimensional pain-related PROs on the first postoperative day. We examined whether the care included [i] regional anesthesia with a neuraxial opioid OR general anesthesia with wound infiltration or a Transvesus Abdominis Plane block; [ii] at least one non-opioid analgesic at the full daily dose; and [iii] pain assessment and recording. Credit for care was given only if all three elements were administered (= “full”); otherwise, it was “incomplete”. A “Pain Composite Score-total” (PCStotal), evaluating outcomes of pain intensity, pain-related interference with function, and side-effects, was the primary endpoint in the total cohort (women receiving GA and/or RA) or a sub-group of women with RA only. Data from 5182 women was analyzed. “Full” care was administered to 20% of women in the total cohort and to 21% in the RA sub-group. In both groups, the PCStotal was significantly lower compared to “incomplete” care (p < 0.001); this was a small-to-moderate effect size. Administering all three elements of care was associated with better pain-related outcomes after CS. These should be straightforward and inexpensive for integration into routine care after CS. However, even in this group, a high proportion of women reported poor outcomes, indicating that additional work needs to be carried out to close the evidence-practice gap so that women who have undergone CS can be comfortable when caring for themselves and their newborn.