Opioid analgesics for nociceptive cancer pain: A comprehensive review.

Pain is one of the most burdensome symptoms in people with cancer, and opioid analgesics are considered the mainstay of cancer pain management. For this review, the authors evaluated the efficacy and toxicities of opioid analgesics compared with placebo, other opioids, nonopioid analgesics, and nonpharmacologic treatments for background cancer pain (continuous and relatively constant pain present at rest), and breakthrough cancer pain (transient exacerbation of pain despite stable and adequately controlled background pain). They found a paucity of placebo-controlled trials for background cancer pain, although tapentadol or codeine may be more efficacious than placebo (moderate-certainty to low-certainty evidence). Nonsteroidal anti-inflammatory drugs including aspirin, piroxicam, diclofenac, ketorolac, and the antidepressant medicine imipramine, may be at least as efficacious as opioids for moderate-to-severe background cancer pain. For breakthrough cancer pain, oral transmucosal, buccal, sublingual, or intranasal fentanyl preparations were identified as more efficacious than placebo but were more commonly associated with toxicities, including constipation and nausea. Despite being recommended worldwide for the treatment of cancer pain, morphine was generally not superior to other opioids, nor did it have a more favorable toxicity profile. The interpretation of study results, however, was complicated by the heterogeneity in the study populations evaluated. Given the limited quality and quantity of research, there is a need to reappraise the clinical utility of opioids in people with cancer pain, particularly those who are not at the end of life, and to further explore the effects of opioids on immune system function and quality of life in these individuals.

Neocortical circuits in pain and pain relief.

The sensory, associative and limbic neocortical structures play a critical role in shaping incoming noxious inputs to generate variable pain perceptions. Technological advances in tracing circuitry and interrogation of pathways and complex behaviours are now yielding critical knowledge of neocortical circuits, cellular contributions and causal relationships between pain perception and its abnormalities in chronic pain. Emerging insights into neocortical pain processing suggest the existence of neocortical causality and specificity for pain at the level of subdomains, circuits and cellular entities and the activity patterns they encode. These mechanisms provide opportunities for therapeutic intervention for improved pain management.

Biophysics of Frequency-Dependent Variation in Paresthesia and Pain Relief during Spinal Cord Stimulation.

The neurophysiological effects of spinal cord stimulation (SCS) for chronic pain are poorly understood, resulting in inefficient failure-prone programming protocols and inadequate pain relief. Nonetheless, novel stimulation patterns are regularly introduced and adopted clinically. Traditionally, paresthetic sensation is considered necessary for pain relief, although novel paradigms provide analgesia without paresthesia. However, like pain relief, the neurophysiological underpinnings of SCS-induced paresthesia are unknown. Here, we paired biophysical modeling with clinical paresthesia thresholds (of both sexes) to investigate how stimulation frequency affects the neural response to SCS relevant to paresthesia and analgesia. Specifically, we modeled the dorsal column (DC) axonal response, dorsal column nucleus (DCN) synaptic transmission, conduction failure within DC fiber collaterals, and dorsal horn network output. Importantly, we found that high-frequency stimulation reduces DC fiber activation thresholds, which in turn accurately predicts clinical paresthesia perception thresholds. Furthermore, we show that high-frequency SCS produces asynchronous DC fiber spiking and ultimately asynchronous DCN output, offering a plausible biophysical basis for why high-frequency SCS is less comfortable and produces qualitatively different sensation than low-frequency stimulation. Finally, we demonstrate that the model dorsal horn network output is sensitive to SCS-inherent variations in spike timing, which could contribute to heterogeneous pain relief across patients. Importantly, we show that model DC fiber collaterals cannot reliably follow high-frequency stimulation, strongly affecting the network output and typically producing antinociceptive effects at high frequencies. Altogether, these findings clarify how SCS affects the nervous system and provide insight into the biophysics of paresthesia generation and pain relief.

AGA Clinical Practice Update on Pain Management in Inflammatory Bowel Disease: Commentary.

DESCRIPTION: Pain is a common symptom among patients with inflammatory bowel disease (IBD). Although pain typically occurs during episodes of inflammation, it is also commonly experienced when intestinal inflammation is quiescent. Many gastroenterologists are at a loss how to approach pain symptoms when they occur in the absence of gut inflammation. We provide guidance in this area as to the evaluation, diagnosis, and treatment of pain among patients with IBD. METHODS: This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. This expert commentary incorporates important as well as recently published studies in this field, and it reflects the experiences of the authors. Formal ratings regarding the quality of evidence or strength of the presented considerations were not included because systematic reviews were not performed.

Qualitative sex differences in pain processing: emerging evidence of a biased literature.

Although most patients with chronic pain are women, the preclinical literature regarding pain processing and the pathophysiology of chronic pain has historically been derived overwhelmingly from the study of male rodents. This Review describes how the recent adoption by a number of funding agencies of policies mandating the incorporation of sex as a biological variable into preclinical research has correlated with an increase in the number of studies investigating sex differences in pain and analgesia. Trends in the field are analysed, with a focus on newly published findings of qualitative sex differences: that is, those findings that are suggestive of differential processing mechanisms in each sex. It is becoming increasingly clear that robust differences exist in the genetic, molecular, cellular and systems-level mechanisms of acute and chronic pain processing in male and female rodents and humans.

Extracorporeal Shock-Wave Lithotripsy and Endoscopy for the Treatment of Pain in Chronic Pancreatitis : A Sham-Controlled, Randomized Trial.

BACKGROUND: No randomized controlled trials have substantiated endoscopic decompression of the pancreatic duct in patients with painful chronic pancreatitis. OBJECTIVE: To investigate the pain-relieving effect of pancreatic duct decompression in patients with chronic pancreatitis and intraductal stones. DESIGN: 24-week, parallel-group, randomized controlled trial (ClinicalTrials.gov: NCT03966781). SETTING: Asian Institute of Gastroenterology in India from February 2021 to July 2022. PARTICIPANTS: 106 patients with chronic pancreatitis. INTERVENTION: Combined extracorporeal shock-wave lithotripsy (ESWL) and endoscopic retrograde pancreatography (ERP) compared with sham procedures. MEASUREMENTS: The primary end point was pain relief on a 0- to 10-point visual analog scale (VAS) at 12 weeks. Secondary outcomes were assessed after 12 and 24 weeks and included 30% pain relief, opioid use, pain-free days, questionaries, and complications to interventions. RESULTS: 52 patients in the ESWL/ERP group and 54 in the sham group were included. At 12 weeks, the ESWL/ERP group showed better pain relief compared with the sham group (mean difference in change, -0.7 [95% CI, -1.3 to 0] on the VAS; P = 0.039). The difference between groups was not sustained at the 24-week follow-up, and no differences were seen for 30% pain relief at 12- or 24-week follow-up. The number of pain-free days was increased (median difference, 16.2 days [CI, 3.9 to 28.5 days]), and the number of days using opioids was reduced (median difference, -5.4 days [CI, -9.9 to -0.9 days]) in the ESWL/ERP group compared with the sham group at 12-week follow-up. Safety outcomes were similar between groups. LIMITATION: Single-center study and limited duration of follow-up. CONCLUSION: In patients with chronic pancreatitis and intraductal stones, ESWL with ERP provided modest short-term pain relief. PRIMARY FUNDING SOURCE: Asian Institute of Gastroenterology and Aalborg University Hospital.

Emotion-centered versus fact-centered medical information to alleviate pain and anxiety in prostate biopsy: A randomized trial.

BACKGROUND: To test the efficacy of emotion-centered (EC) versus fact-centered (FC) written medical information for prostate biopsy to alleviate pain and anxiety in a randomized controlled trial. METHODS: In a single-center, single-blinded study participants were randomized to receive FC or EC (DRKS00022361; 2020). In the EC, the focus was on possible stress reactions and stress-reducing strategies. Participants were asked to complete questionnaires on the day of MRI acquisition (T0) directly before (T1) and after the procedure (T2). The primary outcome measure was the assessment of worst pain in the last 2 h measured by the adapted brief pain inventory. Secondary outcome measures included state anxiety measured by the state-trait anxiety inventory and the subjective evaluation of the impact of the written medical information at T2. For statistical analysis, mixed models were calculated. RESULTS: Of 137 eligible patients, 108 (79%) could be recruited and were randomized. There was a significant effect for time for the outcome variables pain and anxiety. Regarding the comparison for the primary outcome variable worst pain there was a significantly lower increase from T1 to T2 after FC compared to EC (p < 0.004). The course of anxiety displayed no overall group differences. The FC was evaluated as significantly more helpful regarding stress, pain, and anxiety with moderate effect sizes. CONCLUSIONS: FC was favorable with regard to worst experienced pain, assuming that the brief introduction of emotional issues such as stress and coping in written information might be counterproductive particularly in men not used to these subjects.

Virtual reality for pain management in hospitalized patients with cancer: A randomized controlled trial.

BACKGROUND: Hospitalized patients with cancer often experience acute and/or chronic pain. Although virtual reality (VR) has been extensively studied across a wide range of clinical settings, no studies have yet evaluated potential impact on pain management in this patient population. METHODS: Prospective randomized controlled trial at an urban academic hospital comparing VR against an active control to mitigate moderate-severe cancer disease and treatment-related pain. RESULTS: A total of 128 adult hospitalized patients with cancer (any tumor type) were randomized to 10 minutes of immersive VR distraction therapy or 10 minutes of two-dimensional guided imagery distraction therapy delivered by handheld tablet. Participants in the two arms were similar in age, sex, race, presence of metastatic disease, concurrent pain specialist consultation, and baseline opioid use. Although both groups experienced improved self-reported pain scores (primary outcome), those randomized to VR experienced significantly greater reduction in pain immediately after intervention compared with active control (p = .03). This difference was sustained for 24 hours as well (p = .004). Within-group analysis showed significant improvement in VR arm of pain bothersomeness (p = .05) and general distress (p = .03) as well. CONCLUSION: Among hospitalized adult patients with moderate-severe pain related to cancer and cancer therapies, VR provided more nonpharmacologic pain relief than active control and this benefit sustained long after conclusion of the intervention. PLAIN LANGUAGE SUMMARY: Virtual reality (VR), a developing technology that immerses the user in new environments, has been shown to improve pain in different patient populations. To test the role of VR in improving pain in hospitalized patients with cancer who report moderate-severe pain, we compared the impact of a 10-minute immersive VR intervention to that of a 10-minute two-dimensional guided imagery experience to improve self-reported pain scores. We found that, although both interventions improved pain, VR did so significantly more. Moreover, participants assigned to VR had sustained improvement in pain 24 hours later.

Navigating the complexity of pain in psoriatic arthritis and axial spondyloarthritis.

PURPOSE OF REVIEW: Pain is the most common and often most troublesome feature of chronic autoimmune diseases such as psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA). A predominant concept is that the main source of pain is from disease-induced tissue inflammation and structural damage, activating peripheral nerve fibers which relay to the central nervous system. This mechanism is nociceptive pain and the presumption has been that controlling inflammation will be sufficient to reduce this form of pain. However, despite control of inflammation, patients may still have significant residual pain. RECENT FINDINGS: We are learning that there are additional pain mechanisms, neuropathic and nociplastic, that are often operative in patients with rheumatologic conditions, that can significantly influence pain experience, quantitation of disease activity, and may benefit from therapeutic approaches distinct from immunotherapy. Neuropathic pain arises from diseased or damaged nerve tissue and nociplastic pain reflects sensitization of the central nervous system due to multiple genetic, neurobiologic, neural network dysregulation, and psychosocial factors. Pain arising from these mechanisms influence assessment of disease activity and thus needs to be factored into decision-making about immunotherapy efficacy. SUMMARY: This review addresses the importance of accurately assessing the complex mechanisms of pain experience in patients with PsA and AxSpA to more appropriately manage immunomodulatory, neuromodulatory, and nonpharmacologic therapies.

Opioid and Non-Opioid Pharmacotherapy Use for Pain Management Among Privately Insured Pediatric Patients With Cancer in the United States.

BACKGROUND: This study examined the trends and patterns of opioid and non-opioid pharmacotherapy use among a large national sample of privately insured pediatric patients with cancer in the United States. MATERIALS AND METHODS: We identified pediatric (aged < 21) patients diagnosed with central nervous system (CNS), lymphoma, gonadal, leukemia, or bone cancer from MarketScan data 2005-2019. We examined the proportion of patients who filled a prescription for the following 5 types of pharmacotherapy: opioid, anticonvulsant, non-steroidal anti-inflammatory drug (NSAID), antidepressant, and muscle relaxant during active cancer treatment. We assessed the trends and patterns in pharmacotherapy using multivariable logistic regressions. RESULTS: Among 4174 patients included, 2979 (71%) had an opioid prescription; 746 (18%), 384 (9%), 202 (5%), and 169 (4%) had anticonvulsant, NSAID, antidepressant and muscle relaxant prescriptions, respectively. Multivariable logistic regression showed a nonlinear trend in the use of opioids among pediatric patients with cancer over time such that use slightly increased until 2012 (OR of 1.40 [95% CI, 1.12-1.73] for 2012 vs. 2006) but then decreased thereafter (OR of 0.51 [0.37-0.68] for 2018 vs. 2012). The use of anticonvulsants, NSAIDs, and muscle relaxants increased significantly linearly over time (all P < .005). CONCLUSION: There has been a downward trend in the use of opioids in recent years among pediatric patients with cancer and an upward trend in the use of non-opioid pharmacotherapy for pain management potentially as an alternative to opioids.

Racial Inequality in Prescription Opioid Receipt - Role of Individual Health Systems.

BACKGROUND: Historically, the receipt of prescription opioids has differed among racial groups in the United States. Research has not sufficiently explored the contribution of individual health systems to these differences by examining within-system prescription opioid receipt according to race. METHODS: We used 2016 and 2017 Medicare claims data from a random 40% national sample of fee-for-service, Black and White beneficiaries 18 to 64 years of age who were attributed to health systems. We identified 310 racially diverse systems (defined as systems with ≥200 person-years each for Black and White patients). To test representativeness, we compared patient characteristics and opioid receipt among the patients in these 310 systems with those in the national sample. Within the 310 systems, regression models were used to explore the difference between Black and White patients in the following annual opioid measures: any prescription filled, short-term receipt of opioids, long-term receipt of opioids (one or more filled opioid prescriptions in all four calendar quarters of a year), and the opioid dose in morphine milligram equivalents (MME); models controlled for patient characteristics, state, and system. RESULTS: The national sample included 2,197,153 person-years, and the sample served by 310 racially diverse systems included 896,807 person-years (representing 47.4% of all patients and 56.1% of Black patients in the national sample). The national sample and 310-systems sample differed meaningfully only in the percent of person-years contributed by Black patients (21.3% vs. 25.9%). In the 310-systems sample, the crude annual prevalence of any opioid receipt differed slightly between Black and White patients (50.2% vs. 52.2%), whereas the mean annual dose was 36% lower among Black patients than among White patients (5190 MME vs. 8082 MME). Within systems, the adjusted race differences in measures paralleled the population trends: the annual prevalence of opioid receipt differed little, but the mean annual dose was higher among White patients than among Black patients in 91% of the systems, and at least 15% higher in 75% of the systems. CONCLUSIONS: Within individual health systems, Black and White patients received markedly different opioid doses. These system-specific findings could facilitate exploration of the causes and consequences of these differences. (Funded by the National Institute on Aging and the Agency for Healthcare Research and Quality.).

Buprenorphine Versus Diclofenac for Pain Relief in Acute Pancreatitis: A Double-Blinded Randomized Controlled Trial.

BACKGROUND: Although both nonsteroidal anti-inflammatory drugs (NSAIDs) and opioids are used for analgesia in acute pancreatitis (AP), the analgesic of choice is not known. We compared buprenorphine, an opioid, and diclofenac, an NSAID, for analgesia in AP. METHODS: In a double-blind randomized controlled trial, AP patients were randomized to receive intravenous diclofenac or intravenous buprenorphine. Fentanyl was used as rescue analgesia, delivered through a patient-controlled analgesia pump. Primary outcome was the difference in the dose of rescue fentanyl required. Secondary outcomes were the number of effective and ineffective demands of rescue fentanyl, pain-free interval, reduction in visual analogue scale (VAS) score, adverse events, and organ failure development. RESULTS: Twenty-four patients were randomized to diclofenac and 24 to buprenorphine. The 2 groups were matched at baseline. The total amount of rescue fentanyl required was significantly lower in the buprenorphine group:130 µg, interquartile range (IQR), 80-255 vs 520 µg, IQR, 380-1065 (P < .001). The number of total demands was 32 (IQR, 21-69) in the diclofenac arm vs 8 (IQR, 4-15) in the buprenorphine arm (P < .001). The buprenorphine group had more prolonged pain-free interval (20 vs 4 hours; P < .001), with greater reduction in the VAS score at 24, 48, and 72 hours compared with the diclofenac group. These findings were confirmed in the subgroup of moderately severe/severe pancreatitis. Adverse events profile was similar in the 2 groups. CONCLUSIONS: Compared with diclofenac, buprenorphine appears to be more effective and equally safe for pain management in AP patients, even in the subcohort of moderately severe or severe pancreatitis (Trial Registration number: CTRI/2020/07/026914).

Efficacy of virtual reality for pain relief in medical procedures: a systematic review and meta-analysis.

BACKGROUND: Effective pain control is crucial to optimise the success of medical procedures. Immersive virtual reality (VR) technology could offer an effective non-invasive, non-pharmacological option to distract patients and reduce their experience of pain. We aimed to evaluate the efficacy of Immersive virtual reality (VR) technology in reducing patient's pain perception during various medical procedures by conducting a systematic review and meta-analysis. METHODS: We searched MEDLINE, EMBASE, CENTRAL, CINAHL, and SIGLE until December 2022 for all randomised clinical trials (RCT) evaluating any type of VR in patients undergoing any medical procedure. We conducted a random effect meta-analysis summarising standardised mean differences (SMD) with 95% confidence intervals (CI). We evaluated heterogeneity using I 2 and explored it using subgroup and meta-regression analyses. RESULTS: In total, we included 92 RCTs (n = 7133 participants). There was a significant reduction in pain scores with VR across all medical procedures (n = 83, SMD - 0.78, 95% CI - 1.00 to - 0.57, I 2 = 93%, p = < 0.01). Subgroup analysis showed varied reduction in pain scores across trial designs [crossover (n = 13, SMD - 0.86, 95% CI - 1.23 to - 0.49, I 2 = 72%, p = < 0.01) vs parallel RCTs (n = 70, SMD - 0.77, 95% CI - 1.01 to - 0.52, I 2 = 90%, p = < 0.01)]; participant age groups [paediatric (n = 43, SMD - 0.91, 95% CI - 1.26 to - 0.56, I 2 = 87%, p = < 0.01) vs adults (n = 40, SMD - 0.66, 95% CI - 0.94 to - 0.39, I 2 = 89%, p = < 0.01)] or procedures [venepuncture (n = 32, SMD - 0.99, 95% CI - 1.52 to - 0.46, I 2 = 90%, p = < 0.01) vs childbirth (n = 7, SMD - 0.99, 95% CI - 1.59 to - 0.38, I 2 = 88%, p = < 0.01) vs minimally invasive medical procedures (n = 25, SMD - 0.51, 95% CI - 0.79 to - 0.23, I 2 = 85%, p = < 0.01) vs dressing changes in burn patients (n = 19, SMD - 0.8, 95% CI - 1.16 to - 0.45, I 2 = 87%, p = < 0.01)]. We explored heterogeneity using meta-regression which showed no significant impact of different covariates including crossover trials (p = 0.53), minimally invasive procedures (p = 0.37), and among paediatric participants (p = 0.27). Cumulative meta-analysis showed no change in overall effect estimates with the additional RCTs since 2018. CONCLUSIONS: Immersive VR technology offers effective pain control across various medical procedures, albeit statistical heterogeneity. Further research is needed to inform the safe adoption of this technology across different medical disciplines.

Chronic pain in children and young people with cerebral palsy: a narrative review of challenges, advances, and future directions.

BACKGROUND: Cerebral palsy (CP), the most common physical disability of childhood, is often accompanied by a range of comorbidities including pain. Pain is highly prevalent in children and young people with CP, yet has been poorly understood, inaccurately assessed, and inadequately managed in this vulnerable population. This narrative review presents recent research advances for understanding and managing pain in children and young people with CP, focusing on chronic pain, and highlights future research directions. MAIN BODY: Pain prevalence rates in CP vary due to different methodologies of studies. Recent systematic reviews report up to 85% of children experience pain; higher in older children, females, and those with dyskinesia and greater motor impairment. Research examining the lived experience perspectives of children and their families demonstrate that even those with mild motor impairments have pain, children want to self-report pain where possible to feel heard and believed, and management approaches should be individualized. Notably, many children with cognitive and communication impairments can self-report their pain if adjustments are provided and they are given a chance. Past inadequacies of pain assessment in CP relate to a focus on pain intensity and frequency with little focus on pain interference and coping, a lack of tools appropriate for the CP population, and an assumption that many children with cognitive and/or communication limitations are unable to self-report. Recent systematic reviews have identified the most reliable and valid assessment tools for assessing chronic pain. Many were not developed for people with CP and, in their current form, are not appropriate for the spectrum of physical, communication, and cognitive limitations seen. Recently, consensus and co-design in partnership with people with lived experience and clinicians have identified tools appropriate for use in CP considering the biopsychosocial framework. Modifications to tools are underway to ensure feasibility and applicability for the spectrum of abilities seen. CONCLUSION: Recent research advances have improved our understanding of the prevalence, characteristics and lived experience of chronic pain, and refined assessment methods in children and young people with CP. However, the very limited evidence for effective and novel management of chronic pain in this population is where research should now focus.

Clinical Impact of the Implementation Strategies Used to Apply the 2013 Pain, Agitation/Sedation, Delirium or 2018 Pain, Agitation/Sedation, Delirium, Immobility, Sleep Disruption Guideline Recommendations: A Systematic Review and Meta-Analysis.

OBJECTIVES: To summarize the effectiveness of implementation strategies for ICU execution of recommendations from the 2013 Pain, Agitation/Sedation, Delirium (PAD) or 2018 PAD, Immobility, Sleep Disruption (PADIS) guidelines. DATA SOURCES: PubMed, CINAHL, Scopus, and Web of Science were searched from January 2012 to August 2023. The protocol was registered with PROSPERO (CRD42020175268). STUDY SELECTION: Articles were included if: 1) design was randomized or cohort, 2) adult population evaluated, 3) employed recommendations from greater than or equal to two PAD/PADIS domains, and 4) evaluated greater than or equal to 1 of the following outcome(s): short-term mortality, delirium occurrence, mechanical ventilation (MV) duration, or ICU length of stay (LOS). DATA EXTRACTION: Two authors independently reviewed articles for eligibility, number of PAD/PADIS domains, quality according to National Heart, Lung, and Blood Institute assessment tools, implementation strategy use (including Assess, prevent, and manage pain; Both SAT and SBT; Choice of analgesia and sedation; Delirium: assess, prevent, and manage; Early mobility and exercise; Family engagement and empowerment [ABCDEF] bundle) by Cochrane Effective Practice and Organization of Care (EPOC) category, and clinical outcomes. Certainty of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation. DATA SYNTHESIS: Among the 25 of 243 (10.3%) full-text articles included ( n = 23,215 patients), risk of bias was high in 13 (52%). Most studies were cohort ( n = 22, 88%). A median of 5 (interquartile range [IQR] 4-7) EPOC strategies were used to implement recommendations from two (IQR 2-3) PAD/PADIS domains. Cohort and randomized studies were pooled separately. In the cohort studies, use of EPOC strategies was not associated with a change in mortality (risk ratio [RR] 1.01; 95% CI, 0.9-1.12), or delirium (RR 0.92; 95% CI, 0.82-1.03), but was associated with a reduction in MV duration (weighted mean difference [WMD] -0.84 d; 95% CI, -1.25 to -0.43) and ICU LOS (WMD -0.77 d; 95% CI, -1.51 to 0.04). For randomized studies, EPOC strategy use was associated with reduced mortality and MV duration but not delirium or ICU LOS. CONCLUSIONS: Using multiple implementation strategies to adopt PAD/PADIS guideline recommendations may reduce mortality, duration of MV, and ICU LOS. Further prospective, controlled studies are needed to identify the most effective strategies to implement PAD/PADIS recommendations.

Neurotechnology for Pain.

Neurotechnologies for treating pain rely on electrical stimulation of the central or peripheral nervous system to disrupt or block pain signaling and have been commercialized to treat a variety of pain conditions. While their adoption is accelerating, neurotechnologies are still frequently viewed as a last resort, after many other treatment options have been explored. We review the pain conditions commonly treated with electrical stimulation, as well as the specific neurotechnologies used for treating those conditions. We identify barriers to adoption, including a limited understanding of mechanisms of action, inconsistent efficacy across patients, and challenges related to selectivity of stimulation and off-target side effects. We describe design improvements that have recently been implemented, as well as some cutting-edge technologies that may address the limitations of existing neurotechnologies. Addressing these challenges will accelerate adoption and change neurotechnologies from last-line to first-line treatments for people living with chronic pain.

Gabapentin for Postoperative Pain Control and Opioid Reduction in Scrotal Surgery: A Randomized Controlled Clinical Trial.

PURPOSE: To assess the safety and efficacy of gabapentin in reducing postoperative pain among patients undergoing scrotal surgery for male infertility by conducting a randomized, double-blind, placebo-controlled trial. MATERIALS AND METHODS: In this randomized, double-blind, placebo-controlled trial, healthy men undergoing scrotal surgery with a single surgeon were randomized to receive either (1) gabapentin 600 mg given 2 hours preoperatively and 300 mg taken 3 times a day postoperatively for 3 days, or (2) inactive placebo. The primary outcome measure was difference in postoperative pain scores. Secondary outcomes included differences in opioid usage, patient satisfaction, and adverse events. RESULTS: Of 97 patients screened, 74 enrolled and underwent randomization. Of these, 4 men were lost to follow-up, and 70 were included in the final analysis (35 gabapentin, 35 placebo). Both differences in initial postoperative mean pain score (-1.14, 95% CI -2.21 to -0.08, P = .035) and final mean pain score differences (-1.27, 95% CI -2.23 to -0.32, P = .0097) indicated lower gabapentin pain compared to placebo. There were no statistically significant differences in opioid usage, patient satisfaction, or adverse events. CONCLUSIONS: These data suggest that perioperative gabapentin results in a statistically and clinically significant decrease in pain following scrotal surgery. While there was no evidence of an impact on opioid usage or patient satisfaction, given the low risk of adverse events, it may be considered as part of a multimodal pain management strategy.

Contemporary management of pain in cirrhosis: Toward precision therapy for pain.

Chronic pain is highly prevalent in patients with cirrhosis and is associated with poor health-related quality of life and poor functional status. However, there is limited guidance on appropriate pain management in this population, and pharmacologic treatment can be harmful, leading to adverse outcomes, such as gastrointestinal bleeding, renal injury, falls, and hepatic encephalopathy. Chronic pain can be categorized mechanistically into three pain types: nociceptive, neuropathic, and nociplastic, each responsive to different therapies. By discussing the identification, etiology, and treatment of these three mechanistic pain descriptors with a focus on specific challenges in patients with cirrhosis, we provide a framework for better tailoring treatments, including nonpharmacologic therapies, to patients' needs.

Exercise for knee osteoarthritis pain: Association or causation?

Exercise is universally recommended as a primary strategy for the management of knee osteoarthritis (OA) pain. The recommendations are based on results from more than 100 randomized controlled trials (RCTs) that compare exercise to no-attention control groups. However, due to the inherent difficulties with adequate placebo control, participant blinding and the use of patient-reported outcomes, the existing RCT evidence is imperfect. To better understand the evidence used to support a causal relationship between exercise and knee OA pain relief, we examined the existing evidence through the Bradford Hill considerations for causation. The Bradford Hill considerations, first proposed in 1965 by Sir Austin Bradford Hill, provide a framework for assessment of possible causal relationships. There are 9 considerations by which the evidence is reviewed: Strength of association, Consistency, Specificity, Temporality, Biological Gradient (Dose-Response), Plausibility, Coherence, Experiment, and Analogy. Viewing the evidence from these 9 viewpoints did neither bring forward indisputable evidence for nor against the causal relationship between exercise and improved knee OA pain. Rather, we conclude that the current evidence is not sufficient to support claims about (lack of) causality. With our review, we hope to advance the continued global conversation about how to improve the evidence-based management of patients with knee OA.

Improved Postoperative Pain Management Outcomes After Implementation of Enhanced Recovery After Surgery (ERAS) Protocol for Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS-HIPEC).

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) for patients with peritoneal carcinomatosis is promising but has potential for significant morbidity and prolonged hospitalization. Enhanced Recovery After Surgery (ERAS) is a standardized protocol designed to optimize perioperative care. This study describes trends in epidural and opioid use after implementing ERAS for CRS-HIPEC at a tertiary academic center. METHODS: A retrospective analysis of patients undergoing CRS-HIPEC from January 2020 to September 2023 was conducted. ERAS was implemented in February 2022. Medication and outcomes data were compared before and after ERAS initiation. All opioids were converted to morphine milligram equivalents (MMEs). RESULTS: A total of 136 patients underwent CRS-HIPEC: 73 (54%) pre- and 63 (46%) post-ERAS. Epidural usage increased from 63% pre-ERAS to 87% post-ERAS (p = 0.001). Compared with those without epidurals, patients with epidurals had decreased total 7-day oral and intravenous (IV) opioid requirements (45 MME vs. 316 MME; p < 0.001). There was no difference in 7-day opioid totals between pre- and post-ERAS groups. After ERAS, more patients achieved early ambulation (83% vs. 53%; p < 0.001), early diet initiation (81% vs. 25%; p < 0.001), and early return of bowel function (86% vs. 67%; p = 0.012). CONCLUSIONS: ERAS implementation for CRS-HIPEC was associated with increased epidural use, decreased oral and IV opioid use, and earlier bowel function return. Our study demonstrates that epidural analgesia provides adequate pain control while significantly decreasing oral and IV opioid use, which may promote gastrointestinal recovery postoperatively. These findings support the implementation of an ERAS protocol for effective pain management in patients undergoing CRS-HIPEC.