Postsurgical Pain Research Articles

Chronic post-surgical pain after knee arthroplasty: a role of peripheral nerve blocks.

Peripheral nerve blocks are an efficient method of pain control after total knee arthroplasty (TKA), but there is no report of their impact on chronic post-surgical pain (CPSP). This prospective observational study aimed to assess adductor canal block (ACB) and IPACK block (blocks vs. no blocks) on opioid consumption, postoperative pain score, chronic post-surgical pain 2 years after TKA. 166 patients (82 vs. 84) were analyzed. Opioid consumption was less in the group with blocks (9.74 ± 3.87 mg vs. 30.63 ± 11.52 mg) (p < 0.001). CPSP was present in 20.24% of patients in the group without blocks and 6.1% of patients with blocks (p = 0.011). Predictor variables of CPSP included pain before surgery (cut-off of 5.5), pain at rest (cut-off of 2.35), pain during active movement (cut-off: 2.5), and opioid consumption (cut-off: 8 mg). Peripheral nerve blocks provide adequate analgesia, significantly decrease opioid consumption, improve functional outcomes, and reduce CPSP 2 years after surgery.

Single-port robotic extraperitoneal pediatric pyeloplasty using low anterior access: Description of technique and initial experience

IntroductionWe aim to report our surgical technique, functional and radiological outcomes of single port (SP) extraperitoneal robotic pediatric pyeloplasty through a low anterior (3cm) access using a da-Vinci single-port (SP) robotic surgical system in the pediatric population. Material and methodsWe present our initial series of 6 pediatric patients that underwent robotic SP extraperitoneal pyeloplasty between 2022 - 2023. Patient clinicopathologic variables and perioperative outcomes were collected prospectively. ResultsAll cases of SP extraperitoneal pyeloplasty were completed without any intraoperative complications or conversion to an open, laparoscopic, or multi-port robotic pyeloplasty. Total operative times including cystoscopy ranged from 178 mins to 240 mins. All patients tolerated the surgery with minimal postsurgical pain and no narcotic requirement. No intraoperative or immediate postoperative complications were recorded in the cohort. There were no readmissions after discharge at a median follow-up of 12 months (6-18 months) in our series. ConclusionsSingle port extraperitoneal pyeloplasty is a safe and feasible option for upper tract reconstruction in pediatric patients. All patients had complete resolution of symptoms and improvement of hydronephrosis on follow-up imaging.

Cohort profile: the China surgery and anesthesia cohort (CSAC)

The China Surgery and Anaesthesia Cohort (CSAC) study was launched in July 2020 and is an ongoing prospective cohort study recruiting patients aged 40–65 years who underwent elective surgeries with general anaesthesia across four medical centres in China. The general objective of the CSAC study is to improve our understanding of the complex interaction between environmental and genetic components as well as to determine their effects on a wide range of interested surgery/anaesthesia-related outcomes. To achieve this goal, we collected enriched phenotypic data, e.g., sociodemographic characteristics, lifestyle factors, perioperative neuropsychological changes, anaesthesia- and surgery-related complications, and medical conditions, at recruitment, as well as through both active (at 1, 3, 7 days and 1, 3, 6, 12 months after surgery) and passive (for more than 1 year after surgery) follow-up assessments. We also obtained omics data from blood samples. In addition, COVID-19-related information was collected from all participants since January 2023, immediately after COVID-19 restrictions were eased in China. As of July 18, 2023, 12,766 participants (mean age = 52.40 years, 57.93% were female) completed baseline data collection (response rate = 94.68%), among which approximately 70% donated blood and hair samples. The follow-up rates within 12 months after surgery were > 92%. Our initial analyses have demonstrated the incidence of and risk factors for chronic postsurgical pain (CPSP) and postoperative cognitive dysfunction (POCD) among middle-aged Chinese individuals, which may prompt further mechanistic exploration and facilitate the development of effective interventions for preventing those conditions. Additional studies, such as genome-wide association analyses for identifying the genetic determinants of CPSP and POCD, are ongoing, and their findings will be released in the future.

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

BackgroundLong-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. MethodsIn 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. ResultsOf 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). ConclusionsOpioid 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 registrationNCT02083835.

Ventral tegmental area dopaminergic circuits participates in stress-induced chronic postsurgical pain in male mice

BackgroundChronic postsurgical pain (CPP) markedly impairs patients’ quality of life. Research has shown that chronic stress may extend incisional nociception in male mice. Dopaminergic (DAergic) neurons in the ventral tegmental area (VTA) are integral to stress-related mental disorders (including major depressive disorder, anxiety disorders, and PTSD) and pain. However, the impact of chronic social defeat stress (CSDS) on mesolimbic dopamine (DA) transmission in the development of CPP is yet to be established. It remains uncertain whether the dopamine signals in the rostral anterior cingulate cortex (rACC), which regulate pain, derive from the VTA. This study aims to explore the role of VTA-rACC dopaminergic circuits in a mouse model of CPP induced by CSDS.MethodsWe conducted CSDS on C57BL/6 J wild-type male mice (n = 12–16 mice/group) and DAT-cre male mice (n = 10–12 mice/group). After 10 days of CSDS, a left posterior plantar incision was made to establish a mouse model of CPP. Paw withdrawal thresholds (PWTs) were evaluated using Von-Frey fibre stimulation. The open field test (OFT) and elevated plus maze test (EPM) were used to assess pain-related negative emotions. We used immunofluorescence staining and Western Blot to analyse D1, D2, c-Fos, and TH expression. DAergic fibre projections in the VTA-rACC neural pathway were traced using retrograde tracing and immunofluorescence staining. Optogenetics and Chemogenetics were employed to manipulate DAergic neurons in the VTA and their axons in the rACC.ResultsThe ipsilateral PWTs in male C57BL/6 J mice significantly decreased after surgery, returning to baseline after seven days. Conversely, in CSDS mice, ipsilateral PWTs remained reduced for at least 30 days post-incision. A significant reduction in TH-positive neurons expressing c-Fos in the VTA of CPP mice was observed 15 days post-incision. Activating DAergic neurons significantly improved ipsilateral PWTs and locomotor performance in the OFT and EPM in CPP mice post-incision. Additionally, D1 expression in the rACC was found to decrease in CPP mice, and this reduction counteracted the increase in PWTs caused by activating DAergic neuron axon terminals in the rACC.ConclusionCSDS results in chronicity of postsurgical nociception and anxiety-like negative emotions, with alterations in DA transmission playing a role in CPP. Specific activation of DAergic neurons mitigates nociceptive responses and anxiety-like bahaviors, possibly mediated by D1 receptors in the rACC.

β-Caryophyllene Inhibits Monoacylglycerol Lipase Activity and Increases 2-Arachidonoyl Glycerol Levels In Vivo: A New Mechanism of Endocannabinoid-Mediated Analgesia?

The mechanisms of β-caryophyllene (BCP)-induced analgesia are not well studied. Here, we tested the efficacy of BCP in an acute postsurgical pain model and evaluated its effect on the endocannabinoid system. Rats were treated with vehicle and 10, 25, 50, and 75 mg/kg BCP. Paw withdrawal responses to mechanical stimuli were evaluated using an electronic von Frey anesthesiometer. Endocannabinoids, including 2-arachidonoylglycerol (2-AG), were also evaluated in plasma and tissues using high-performance liquid chromatography-tandem mass spectrometry. Monoacylglycerol lipase (MAGL) activity was evaluated in vitro as well as ex vivo. We observed a dose-dependent and time-dependent alleviation of hyperalgesia in incised paws up to 85% of the baseline value at 30 minutes after administration of BCP. We also observed dose-dependent increases in the 2-AG levels of about threefold after administration of BCP as compared with vehicle controls. Incubations of spinal cord tissue homogenates from BCP-treated rats with isotope-labeled 2-arachidonoylglycerol-d8 revealed a reduced formation of the isotope-labeled MAGL product 2-AG-d8 as compared with vehicle controls, indicating MAGL enzyme inhibition. In vitro MAGL enzyme activity assessment using 2-AG as the substrate revealed an IC50 of 15.8 µM for MAGL inhibition using BCP. These data showed that BCP inhibits MAGL activity in vitro and in vivo, causing 2-AG levels to rise. Since the endocannabinoid 2-AG is a CB1 and CB2 receptor agonist, we propose that 2-AG-mediated cannabinoid receptor activation contributes to BCP's mechanism of analgesia. SIGNIFICANCE STATEMENT: β-Caryophyllene (BCP) consumption is relatively safe and is approved by the Food and Drug Administration as a flavoring agent, which can be used in cosmetic and food additives. BCP is a potent anti-inflammatory agent that showed substantial antihyperalgesic properties in this study of acute pain suggesting that BCP might be an alternative to opioids. This study shows an additive mechanism (monoacylglycerol lipase inhibition) by which BCP might indirectly alter CB1 and CB2 receptor activity and exhibit its pharmacological properties.

In-person cognitive behavioural therapy vs. usual care after surgical management of extremity fractures: an unsuccessful feasibility trial

BackgroundExtremity fractures are common, and most are managed operatively; however, despite successful reduction, up to half of patients report persistent post-surgical pain. Furthermore, psychological factors such as stress, distress, anxiety, depression, catastrophizing, and fear-avoidance behaviors have been associated with the development of chronic pain. The purpose of this pilot study was to examine the feasibility of a randomized controlled trial to determine the effect of in-person cognitive behavioral therapy (CBT) vs. usual care on persistent post-surgical pain among patients with a surgically managed extremity fracture.MethodsEligible patients were randomized to either in-person CBT or usual care. We used four criteria to judge the composite measure of feasibility: 1) successful implementation of CBT at each clinical site, 2) 40 patients recruited within 6 months, 3) treatment compliance in a minimum 36 of 40 participants (90%), and 4) 32 of 40 participants (80%) achieving follow-up at one year. The primary clinical outcome was persistent post-surgical pain at one year after surgery.ResultsOnly two of the four participating sites were able to implement the CBT regimen due to difficulties with identifying certified therapists who had the capacity to accommodate additional patients into their schedule within the required timeframe (i.e., 8 weeks of their fracture). Given the challenges associated with CBT implementation, only one site was able to actively recruit patients. This site screened 86 patients and enrolled 3 patients (3.5%) over a period of three months. Participants were unable to comply with the in-person CBT, with no participants attending an in-person CBT session. Follow-up at one year could not be assessed as the pilot study was stopped early, three months into the study, due to failure to achieve the other three feasibility criteria.ConclusionOur pilot trial failed to demonstrate the feasibility of a trial of in-person CBT versus usual care to prevent persistent pain after surgical repair of traumatic long-bone fractures and re-enforces the importance of establishing feasibility before embarking on definitive trials. Protocol modifications to address the identified barriers include the delivery of our intervention as a therapist-guided, remote CBT program.Trial registrationClinicalTrials.gov (Identifier NCT03196258); Registered June 22, 2017, https://clinicaltrials.gov/ct2/show/NCT03196258

Lumbar foraminal pathology: Biportal endoscopic spine surgical approaches

Spinal endoscopic approaches, full-endoscopic or biportal, allow for access to various lumbar foraminal pathologies while preserving the integrity of back muscles and facet joints. These minimal invasive procedures can eliminate the need for wide decompressions potentially decreasing the need for instrumented fusion. Early symptomatic recurrence most often arises due to inadequate decompression. Understanding the intricacies of foraminal pathology rather than assuming continued post-surgical pain is a result of spinal instability can change the paradigm of endoscopic spine surgery from endoscopic assisted fusion to true minimally invasive surgery. Surgeons should think whether early revision of spinal decompression could arise from insufficient foraminal decompression. This paper aims to elucidate the reader on foraminal pathoanatomy allowing the surgeon to understand when sufficient decompression is achieved and inform the surgeon on the technical aspects of surgery to minimize iatrogenic instability and incidental complications.

Effects of Physical Exercise and Motor Activity on Depression and Anxiety in Post-Mastectomy Pain Syndrome.

Chronic post-surgical pain is a condition persisting for not less than 3 months after surgical intervention. It is evaluated that 25-60% of women who underwent breast cancer excision suffer from post-mastectomy pain syndrome, and anxiety, depression, sleep disturbance, and catastrophizing. Physical activity can reduce the risk of chronic diseases and has a good impact on mood and cognitive function. The aim of this study was to estimate the influence of physical activity on the intensity of pain, depression, and anxiety in women who underwent mastectomy for breast cancer removal. A prospective observational unicentric cohort study was performed. Patients were females who underwent unilateral or bilateral mastectomy. The Numerical Rating Scale (NRS) was used to measure pain intensity, Beck's Depression Inventory (BDI) for depression, and Generalized Anxiety Disorders-7 (GAD-7) for anxiety evaluation. Physical activity was assessed by the International Physical Activity Questionnaire (IPAQ). Interleukin (IL)-17, IL-1β, cortisol, adrenocorticotropic hormone (ACTH), and brain-derived neurotrophic factor (BDNF) were also evaluated in the blood of patients. All evaluations were assessed 3 and 6 months after the surgery. Adequate physical activity reduced the intensity of pain, depression, and anxiety symptoms in women affected by post-mastectomy pain syndrome. Moreover, adequately active women showed a reduction in biomarkers of inflammation, cortisol, ACTH, and an increase of BDNF. Our results suggest that physical activity can improve the quality of life, reduce the intensity of pain and inflammatory markers, and be useful in the reduction of associated anxiety and depression.

The Effects of Massage Therapy in Decreasing Pain and Anxiety in Post-Surgical Patients With Breast Cancer: A Systematic Review and Meta-Analysis.

Massage therapy is an effective non-pharmacological intervention in treating pain and anxiety of patients with cancer. Prior studies have reviewed the benefits of massage therapy in patients with breast cancer undergoing chemotherapy, radiation, and other patient-specific cancer treatments. What has yet to be examined is the effects of massage therapy on the pain and anxiety of patients with breast cancer after surgery. : The purpose of this systematic review and meta-analysis was to examine the effect of massage therapy on post-surgical pain and anxiety in patients with breast cancer. Systematic searches were performed using databases PubMed, CINAHL, and Medline (EBSCO), with no date constraint through September 30, 2023, to identify randomized control trials, randomized pilot, and quasi-experimental studies. The database searches retrieved 1205 titles, and after screening, 7 studies were chosen for full analysis using Cohen's d, 95% Confidence Interval (CI), and effect size. The heterogeneity of the studies was calculated in the meta-analysis using Cochran's Q equation. Massage therapy techniques reported were massage therapy, classic massage, reflexology, myofascial release, and myofascial therapy, and were performed at day 0 up to 16weeks post-surgery. Massage therapy decreased pain and anxiety for patients in the massage group. Analyses showed a positive effect size using massage therapy as an intervention for pain and anxiety in women with breast cancer post-surgery. Overall effect size for pain was 1.057 with a P-value of <.0001, and overall effect size for anxiety was .673 with a P-value of <.0001. The current evidence in this study reflects that massage therapy is effective as a non-pharmacological tool in decreasing post-surgical pain and anxiety in women with breast cancer.

Is the application of subcostal transversus abdominis plane block effective for pain control in classical four-port laparoscopic cholecystectomy?

The utilization of transversus abdominis plane (TAP) block for postoperative pain management has proven to be efficacious. The purpose of this inquiry is to evaluate the effectiveness of right-sided TAP blockade guided by ultrasonography (USG) in managing pain subsequent to laparoscopic cholecystectomy. A total of 60 patients were equallydistributed into two groups. The control group was comprised of patients who did not receive a TAP block, whereas the TAP block group consisted of patients who underwent an ultrasound-guided, right-sided unilateral subcostal TAP block with 20 mL of 0.25% bupivacaine. A Verbal Numerical Rating Scale was administered to all participants for pain assessment at postoperative intervals of 0th, 6th, 12th and 24th hours. Additionally, the overall amount of supplementary analgesic used after surgery, age distribution among each gender classification and body mass index range categories as well as operation time duration; use or non-use of drain; and incidence rate for postoperative complications were recorded for each patient individually. The mean age of participants was 47.72 ± 13.80 years, with a female-to-male ratio of 41/19. The control group exhibited significantly higher pain scale measurements than the block group at the postoperative 0th and the postoperative 24th hour. Drain replacement yielded notably higher pain scores for both TAP and control groups at the postoperative 0th hour. Neither BMI nor operation duration had significant effects on postsurgical pain in either patient group—whether or not they received a TAP block treatment. Our research shows that the implementation of a TAP block and exclusion of surgical area drainage placement yield favorable results in mitigating postoperative pain. Notably, BMI and procedure duration do not exhibit any discernible impact on postoperative pain management.

Efficacy of Ultrasound-guided Transverse Abdominis Plane Block versus Epidural Block in Nephrectomy Patients: A Randomised Controlled Study

Introduction: Partially controlled acute pain after abdominal surgery is associated with a variety of unwanted postoperative consequences, like respiratory complications, delirium, myocardial ischaemia, prolonged hospital stays, and chronic pain later on. A good postoperative recovery depends greatly on a proper analgesic regimen. While epidural analgesia has been used to provide postsurgical abdominal pain relief, peripheral nerve blockade is a good alternative. Aim: To compare the analgesic efficacy of Transverse Abdominis Plane (TAP) block and Epidural block in patients undergoing nephrectomy. Materials and Methods: In this single-blinded parallel-group randomised controlled study was conducted in the Department of Urology at the Institute f Postgraduate Medical Education and Research in Kolkata, West Bengal, India from November 2021 to October 2022. A total of 78 patients (18-65 years) with American Society of Anaesthesiologists (ASA) Grade-I and II were randomly assigned to Group-EA (Epidural) and Group-TA (TAP Block). Group-EA received 11 mL of 0.125% bupivacaine, and Group-TA received 11 ml of 0.125% bupivacaine, both given at an 8-hour interval for 24 hours. The primary outcome was to compare postoperative pain using the Visual Analogue Scale (VAS) score at 1, 8, 12, and 24 hours after surgery. Secondary outcome measures included assessing motor function using the Bromage Score, monitoring haemodynamic parameters (pulse rate, mean arterial pressure), and evaluating Postoperative Nausea and Vomiting (PONV). A p-value &lt;0.05 was considered statistically significant when comparing the data. Results: The authors found that the distribution of male and female patients (p=0.650), ASA Grades (I:II) (p=0.515), mean age (p=0.899), and mean SpO2 (p=0.404) were comparable between the two groups (p&gt;0.05). The pain scores between the EA and TA groups at 1, 8, 12, and 24 hours (0.10 vs. 0.08, 0.74 vs. 0.82, 1.00 vs. 1.31, 1.80 vs. 1.92) showed no significant difference at the specified times. However, the comparison of the mean Bromage scores in the EA and TA groups at the same time intervals (1 vs. 1.15, 1.08 vs. 2.51, 1.97 vs. 3.21, 1.97 vs. 4.74) revealed a significantly higher value in the TAP block group compared to the Epidural block group. The Epidural group had significantly lower blood pressure and pulse rate but experienced more PONV (15.4 vs. 2.6) compared to the TAP block group. Conclusion: Epidural block resulted in hypotension, bradycardia, shivering, and PONV as side-effects, which were negligible in the TAP block group. However, postoperative analgesia was quite comparable between the two groups. Postoperative pain, as assessed by VAS score, changed significantly in the TAP block group (intragroup p-value=0.0063), whereas it remained constant in the epidural group (intragroup p-value 0.094), and the difference between the two groups was statistically insignificant. The occurrence of hypotension, bradycardia, and PONV was significant in the epidural group, whereas postoperative mobility was better in the TAP group.

Efficacy of Ultrasound-guided Transverse Abdominis Plane Block versus Epidural Block in Nephrectomy Patients: A Randomised Controlled Study

Introduction: Partially controlled acute pain after abdominal surgery is associated with a variety of unwanted postoperative consequences, like respiratory complications, delirium, myocardial ischaemia, prolonged hospital stays, and chronic pain later on. A good postoperative recovery depends greatly on a proper analgesic regimen. While epidural analgesia has been used to provide postsurgical abdominal pain relief, peripheral nerve blockade is a good alternative. Aim: To compare the analgesic efficacy of Transverse Abdominis Plane (TAP) block and Epidural block in patients undergoing nephrectomy. Materials and Methods: In this single-blinded parallel-group randomised controlled study was conducted in the Department of Urology at the Institute f Postgraduate Medical Education and Research in Kolkata, West Bengal, India from November 2021 to October 2022. A total of 78 patients (18-65 years) with American Society of Anaesthesiologists (ASA) Grade-I and II were randomly assigned to Group-EA (Epidural) and Group-TA (TAP Block). Group-EA received 11 mL of 0.125% bupivacaine, and Group-TA received 11 ml of 0.125% bupivacaine, both given at an 8-hour interval for 24 hours. The primary outcome was to compare postoperative pain using the Visual Analogue Scale (VAS) score at 1, 8, 12, and 24 hours after surgery. Secondary outcome measures included assessing motor function using the Bromage Score, monitoring haemodynamic parameters (pulse rate, mean arterial pressure), and evaluating Postoperative Nausea and Vomiting (PONV). A p-value &lt;0.05 was considered statistically significant when comparing the data. Results: The authors found that the distribution of male and female patients (p=0.650), ASA Grades (I:II) (p=0.515), mean age (p=0.899), and mean SpO2 (p=0.404) were comparable between the two groups (p&gt;0.05). The pain scores between the EA and TA groups at 1, 8, 12, and 24 hours (0.10 vs. 0.08, 0.74 vs. 0.82, 1.00 vs. 1.31, 1.80 vs. 1.92) showed no significant difference at the specified times. However, the comparison of the mean Bromage scores in the EA and TA groups at the same time intervals (1 vs. 1.15, 1.08 vs. 2.51, 1.97 vs. 3.21, 1.97 vs. 4.74) revealed a significantly higher value in the TAP block group compared to the Epidural block group. The Epidural group had significantly lower blood pressure and pulse rate but experienced more PONV (15.4 vs. 2.6) compared to the TAP block group. Conclusion: Epidural block resulted in hypotension, bradycardia, shivering, and PONV as side-effects, which were negligible in the TAP block group. However, postoperative analgesia was quite comparable between the two groups. Postoperative pain, as assessed by VAS score, changed significantly in the TAP block group (intragroup p-value=0.0063), whereas it remained constant in the epidural group (intragroup p-value 0.094), and the difference between the two groups was statistically insignificant. The occurrence of hypotension, bradycardia, and PONV was significant in the epidural group, whereas postoperative mobility was better in the TAP group.

Effect of 5% lidocaine-medicated plaster in preventing chronic postsurgical pain after knee replacement: protocol for a randomized double-blind placebo-controlled trial.

With an aging population, knee arthroplasty is increasingly common; however, chronic postsurgical pain (CPSP) affects up to 30% of patients. This study aims to evaluate the efficacy of 5% lidocaine-medicated plaster (LP5) in preventing CPSP among patients undergoing knee arthroplasty. This is a dual-center, randomized, double-blind, placebo-controlled trial involving 128 adult patients scheduled for knee arthroplasty. Participants will be randomly assigned, stratified by center, to either the LP5 group or the placebo group (n = 64 per group). The LP5 or placebo group will apply the patch 1day before surgery and on postoperative days 1-3, with multimodal analgesia administered postoperatively. Multimodal analgesia will include intraoperative flurbiprofen axetil and postoperative patient-controlled sufentanil. The primary outcome is the pain subscale of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at 3 months postoperatively. Secondary outcomes will include WOMAC stiffness, function, and total scales; Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) Pain Scale; 36-Item Short Form Health Survey (SF-36); postoperative pain scores; Visual Analog Scale (VAS) sleep scores; postoperative sufentanil consumption; need for rescue analgesia; length of Post-Anesthesia Care Unit (PACU) stay; length of hospital stay; and 90-day mortality. Safety outcomes will include assessments of hypotension, hypertension, bradycardia, tachycardia, arrhythmia, interventions for haemodynamic events, headache, dizziness, nausea, vomiting, local skin allergy, wound infection, and toxic reaction. Data will be analyzed following a modified intention-to-treat approach. This study aims to provide high-quality evidence for the efficacy and safety of LP5 in preventing CPSP in patients undergoing knee arthroplasty.

Ecological momentary assessment of sleep, pain, and opioid use among adolescents following surgery.

Opioids are effective for acute pain management following surgery among adolescents, yet are associated with significant negative consequences, including respiratory depression and opioid misuse. Sleep deficiency is common following surgery and extant research indicates strong cross-sectional associations between sleep deficiency and increased problematic opioid use. This study examined longitudinal associations between postsurgical sleep deficiency and opioid use among adolescents undergoing outpatient surgery. We also examined daily pain and mood as mechanisms linking previous night's sleep deficiency and next day prescription opioid use. This prospective, observational study enrolled 106 adolescents (11-19 years) who underwent orthopedic outpatient surgery and collected pre-surgery and longitudinal measurements. Participants were 52% female, African-American (7%), American Indian/Alaska Native (7%), Hispanic (9%), Native Hawaiian or Other Pacific Islander (4%), or white, non-Hispanic (66%). Using ecological momentary assessment methods, participants reported sleep, pain, and mood in real time over the first 14 days following surgery. Postsurgical opioid use was measured using an electronic medication cap monitoring device, eCAPTM. Associations between variables were measured using multilevel structural equation modeling. Using multi-level mediation models, pain, but not mood-mediated associations between postsurgical sleep deficiency (sleep quality, total sleep time, sleep onset latency, and wake after sleep onset) and opioid use, at both the within-person and between-person levels. Results highlight that greater previous night's sleep deficiency (both generally and greater than a person's mean level) was associated with higher next day pain (both generally and greater than a person's mean level), which, in turn, was associated with higher opioid use. Furthermore, between-person total effect models provide support for sleep deficiency predicting higher opioid use. Our findings should be considered preliminary yet underscore the need for a comprehensive and personalized approach to postsurgical pain management and opioid use, potentially implementing interventions targeting sleep quality and quantity to reduce pain and opioid use.

Determination of the Frequency and Affecting Factors of Chronic Postsurgical Pain After Cardiac Surgery (CPSP-Cardiac): Protocol for a Multicenter, Observational Study

Determination of the Frequency and Affecting Factors of Chronic Postsurgical Pain After Cardiac Surgery (CPSP-Cardiac): Protocol for a Multicenter, Observational Study

Effect of dog-owner interaction on post-operative pain perception and stress of dogs and variability in their behavioural patterns

Abstract Pain, a multifaceted condition associated with actual or potential tissue damage, transcends nociception and is characterised as a subjective, sensory, and emotional experience. Extensive literature describing the adverse effects of untreated post-surgical pain emphasises the necessity of a comprehensive pain management protocol, incorporating both pharmacological and non-pharmacological strategies to ensure successful patient outcomes. The present study aimed to determine whether a positive dog-owner interaction influences post-operative pain perception and stress (POPPS), as well as behavioural inactive rate variability in bitches that underwent elective surgery. Randomly selected bitches (n = 18) underwent ovariohysterectomy. Eight bitches experienced a 45-min visit post-surgery (VPS) characterised by positive dog-owner interaction, while the remaining ten did not (NVPS). Utilising the validated Short Form of the Glasgow Composite Measure Pain Scale (CMPS-SF) to assess acute pain in dogs via stress-related behaviours, a significant decrease in POPPS was evident in the VPS group after the 45-min dog-owner interaction at T3 (1 h after post-sedation recovery), in contrast to the NVPS group. CMPS-SF-associated descriptive items ‘Nervous/Anxious/Fearful’ and ‘Happy Content or Happy and Bouncy’ decreased and increased, respectively, with dog-owner positive interaction in the VPS group. The inactivity rate was significantly lower in VPS bitches after the post-surgery 45-min dog-owner interaction than in NVPS bitches. This preliminary study suggests that the owner’s presence reduces POPPS and may improve the dogs’ welfare while undergoing routine surgeries.

Impact of CYP2D6 and CYP2B6 phenotypes on the response to tramadol in patients with acute post-surgical pain.

Tramadol is an important minor opioid prescribed for pain management. In this study, we analyzed the well-known impact of CYP2D6 genetic variation and 60 additional variants in eight candidate genes (i.e., ABCG2, SLCO1B1, CYP2D6, CYP2B6, CYP2C19, CYP2C9, CYP3A5, and CYP3A4) on tramadol efficacy and safety. Some 108 patients with pain after surgery admitted to a post-anesthesia care unit (PACU) and prescribed tramadol were recruited. They were genotyped, and tramadol M1/M2 metabolite concentrations were determined by a newly validated HPLC-MS/MS method. CYP2D6 intermediate (IM) and poor (PM) metabolizers showed lower M1 concentrations adjusted for dose/weight at 30 and 120 min compared to ultrarapid (UM) and normal (NM) metabolizers (univariate p < 0.001 and 0.020, multivariate p < 0.001 and 0.001, unstandardized β coefficients = 0.386 and 0.346, R2 = 0.146 and 0.120, respectively). CYP2B6 PMs (n = 10) were significantly related to a higher reduction in pain 30 min after tramadol intake (univariate p = 0.038, multivariate p = 0.016, unstandardized β coefficient = 0.224, R2 = 0.178), to lower PACU admission time (p = 0.007), and to lower incidence of adverse drug reactions (p = 0.038) compared to the other phenotypes. CYP3A4 IMs and PMs showed a higher prevalence of drowsiness and dizziness (p = 0.028 and 0.005, respectively). Our results suggest that the interaction of CYP2B6 and CYP2D6 phenotypes may be clinically relevant, pending validation of these results in large, independent cohorts. Additional research is required to clarify the impact of CYP3A4 genetic variation on tramadol response.

Pain Catastrophizing and Acute Post-Surgical Pain in Knee Arthroplasty Patients: The Moderating Role of Social Support.

This study aimed to investigate the correlation between preoperative pain catastrophizing and social support, and acute post-surgical pain in patients who underwent knee arthroplasty. The study also aimed to determine whether social support moderates the role of pain catastrophizing psychologically in acute post-surgical pain after knee arthroplasty. This study recruited participants to survey a tertiary hospital in Dalian, China, between November 2022 and October 2023. Participants completed pain catastrophizing scales and social support reevaluated scales one day (T1) before they were confirmed to undergo knee arthroplasty, and finished the Numeric Rating Scale at 24h (T2), 48h (T3), and 72h (T4) postoperatively. Pearson correlation analyses were used to explore the relationship between social support, pain catastrophizing, and acute post-surgical pain, hierarchical regression analysis was used to test the moderating role of social support between pain catastrophizing and acute post-surgical pain. This study recruited 178 knee arthroplasty patients. The results of the t-test or one-way ANOVA indicated that there were statistically significant differences in gender, age, education, occupation, disease duration, whether the knee replacement was performed for the first time, preoperative pain scores, and operation time in patients with knee arthroplasty (P < 0.05). The correlation analysis of social support, pain catastrophization, and acute post-surgical pain in knee arthroplasty patients showed that social support was negatively correlated with acute post-surgical pain (r=-0.584, P<0.01), and pain catastrophizing was positively correlated with postoperative acute pain (r=0.601, P<0.01); The hierarchical regression analysis revealed that social support had a significant moderating effect on the relationship between pain catastrophizing and acute post-surgical pain (ΔR2=0.606, P<0.05). The acute post-surgical pain of knee arthroplasty patients was affected by gender, age, education, occupation, disease duration, whether the knee arthroplasty was performed for the first time, preoperative pain scores, and operation time. Acute Post-surgical pain in patients with knee arthroplasty was affected by social support and pain catastrophizing, and social support had a moderating effect on the relationship between pain catastrophizing and acute post-surgical pain.

Acute and Chronic Pain Management of the Urologic Patient

Objectives: Here, we review opioid-sparing or opioid-free anesthesia and pain management for urologic procedures and pathologies–urological pain syndromes, kidney stone pain management, development of post-surgical pain syndromes, and prevention. We explore acute management of perioperative pain during and after urologic procedures; additionally, we review the pathophysiology of various urologic pain syndromes along with a variety of interventions, including pharmacologic management, nerve blocks, neurolysis, and neuromodulatory therapies in hopes of educating providers who treat the urologic patient. Methods: Relevant literature on various topics related to acute and chronic urologic pain was reviewed and incorporated into this comprehensive overview. Relevant clinical treatments and treatment guidelines for managing pain related to various urological conditions and syndromes are discussed, compared, and contrasted and conclusions are drawn. Results and Discussion: Urological pathologies, procedures, pain syndromes and their pharmacologic and interventional pain management strategies are discussed. Conclusion: Acute and chronic pain remain essential components of postoperative morbidity, both in the urologic patient and otherwise. The opioid epidemic has further complicated perioperative management, but effective pain control is vital to improving patient outcomes. Close collaboration between urologists, anesthesiologists, and pain specialists is critical in improving patient care.