Pain coping, multidisciplinary care, and mHealth: Patients' views on managing advanced cancer pain.

OBJECTIVE: Pain is common among people with advanced cancer. While opioids provide significant relief, incorporating psycho-behavioral treatments may improve pain outcomes. We examined patients' experiences with pain self-management and how their self-management of chronic, cancer-related pain may be complemented by behavioral mobile health (mHealth) interventions. METHODS: We conducted semi-structured qualitative interviews with patients with advanced cancer and pain. Each participant reviewed content from our behavioral mHealth application for cancer pain management and early images of its interface. Participants reflected on their experiences self-managing cancer pain and on app content. Interviews were transcribed verbatim and analyzed using a combination of inductive and deductive thematic analysis. RESULTS: Patients (n = 28; 54% female; mean age = 53) across two geographic regions reported using psychological strategies (e.g., reframing negative thoughts, distraction, pain acceptance, social support) to manage chronic cancer-related pain. Patients shared their perspectives on the integration of psycho-behavioral pain treatments into their existing medical care and their experiences with opioid hesitancy. Patient recommendations for how mHealth interventions could best support them coalesced around two topics: 1.) convenience in accessing integrated pharmacological and psycho-behavioral pain education and communication tools and 2.) relevance of the specific content to their clinical situation. CONCLUSIONS: Integrated pharmacological and psycho-behavioral pain treatments were important to participants. This underscores a need to coordinate complimentary approaches when developing cancer pain management interventions. Participant feedback suggests that an mHealth intervention that integrates pain treatments may have the capacity to increase advanced cancer patients' access to destigmatizing, accessible care while improving pain self-management.

Development and pre-pilot testing of STAMP + CBT: an mHealth app combining pain cognitive behavioral therapy and opioid support for patients with advanced cancer and pain.

PURPOSE: We developed and piloted a mobile health app to deliver cognitive behavioral therapy for pain (pain-CBT), remote symptom monitoring, and pharmacologic support for patients with pain from advanced cancer. METHODS: Using an iterative process of patient review and feedback, we developed the STAMP + CBT app. The app delivers brief daily lessons from pain-CBT and pain psychoeducation, adapted for advanced cancer. Daily surveys assess physical symptoms, psychological symptoms, opioid utilization and relief. Just-in-time adaptive interventions generate tailored psychoeducation in response. We then conducted a single-arm pilot feasibility study at two cancer centers. Patients with advanced cancer and chronic pain used the app for 2 or 4 weeks, rated its acceptability and provided feedback in semi-structured interviews. Feasibility and acceptability were defined as ≥ 70% of participants completing ≥ 50% of daily surveys, and ≥ 80% of acceptability items rated ≥ 4/5. RESULTS: Fifteen participants (female = 9; mean age = 50.3) tested the app. We exceeded our feasibility and accessibility benchmarks: 73% of patients completed ≥ 50% of daily surveys; 87% of acceptability items were rated ≥ 4/5. Participants valued the app's brevity, clarity, and salience, and found education on stress and pain to be most helpful. The app helped participants learn pain management strategies and decrease maladaptive thoughts. However, participants disliked the notification structure (single prompt with one snooze), which led to missed content. CONCLUSION: The STAMP + CBT app was an acceptable and feasible method to deliver psychological/behavioral treatment with pharmacologic support for cancer pain. The app is being refined and will be tested in a larger randomized pilot study. TRN: NCT05403801 (05/06/2022).

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

BACKGROUND: Understanding factors that explain why some women experience greater postoperative pain and consume more opioids after cesarean delivery is crucial to building an evidence base for personalized prevention. Comprehensive psychosocial assessment with validated questionnaires in the preoperative period can be time-consuming. A three-item questionnaire has shown promise as a simpler tool to be integrated into clinical practice, but its brevity may limit the ability to explain heterogeneity in psychosocial pain modulators among individuals. This study compared the explanatory ability of three models: (1) the 3-item questionnaire, (2) a 58-item questionnaire (long) including validated questionnaires (e.g., Brief Pain Inventory, Patient Reported Outcome Measurement Information System [PROMIS]) plus the 3-item questionnaire, and (3) a novel 19-item questionnaire (brief) assessing several psychosocial factors plus the 3-item questionnaire. Additionally, this study explored the utility of adding a pragmatic quantitative sensory test to models. METHODS: In this prospective, observational study, 545 women undergoing cesarean delivery completed questionnaires presurgery. Pain during local anesthetic skin wheal before spinal placement served as a pragmatic quantitative sensory test. Postoperatively, pain and opioid consumption were assessed. Linear regression analysis assessed model fit and the association of model items with pain and opioid consumption during the 48 h after surgery. RESULTS: A modest amount of variability was explained by each of the three models for postoperative pain and opioid consumption. Both the brief and long questionnaire models performed better than the three-item questionnaire but were themselves statistically indistinguishable. Items that were independently associated with pain and opioid consumption included anticipated postsurgical pain medication requirement, surgical anxiety, poor sleep, pre-existing pain, and catastrophic thinking about pain. The quantitative sensory test was itself independently associated with pain across models but only modestly improved models for postoperative pain. CONCLUSIONS: The brief questionnaire may be more clinically feasible than longer validated questionnaires, while still performing better and integrating a more comprehensive psychosocial assessment than the three-item questionnaire.

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

PURPOSE: Patients with cancer may experience pain from cancer itself or its treatment. Additionally, chronic pain (CP) predating a patient's cancer diagnosis may make the etiology of pain less clear and the management of pain more complex. In this brief report, we investigated differences in biopsychosocial characteristics, pain severity, and opioid consumption, comparing groups of cancer patients with and without a history of CP who presented to the emergency department (ED) with a complaint of cancer-related pain. METHODS: This secondary analysis of a prospective cohort study included patients with cancer who presented to the ED with a complaint of pain (≥ 4/10). Sociodemographic, clinical, psychological, and pain characteristics were assessed in the ED and subsequent hospitalization. Mann-Whitney U-, T-, and Chi-square tests were used to compare differences between patients with and without pre-existing CP before cancer. RESULTS: Patients with pre-existing CP had lower income (p = 0.21) and less formal education (p = 0.25) and were more likely to have a diagnosis of depression or substance use disorder (p < 0.01). Patients with pre-existing CP reported significantly greater pain severity in the ED and during hospitalization compared to those without pre-existing CP (p < 0.05), despite receiving greater amounts of opioid analgesics (p = 0.036). CONCLUSION: Identifying a history of pre-existing CP during intake may help identify patients with cancer with difficult to manage pain, who may particularly benefit from multimodal interventions and supportive care. In addition, referral of these patients for the management of co-occurring pain disorders may help decrease the usage of the ED for undertreated pain.

Individuals with fibromyalgia report greater pain sensitivity than healthy adults while listening to their favorite music: the contribution of negative affect.

OBJECTIVE: We investigated the impact of favorite music on pain processing among individuals with fibromyalgia. We also examined differences in pain processing between individuals with fibromyalgia and healthy controls (HC) while listening to favorite music and explored whether psychosocial factors contributed to these differences. METHODS: Individuals with fibromyalgia and HC completed baseline psychosocial questionnaires and then underwent quantitative sensory testing (QST) during 3 randomized music conditions (meditative music, favorite music, white noise). Among individuals with fibromyalgia, Friedman tests were used to investigate differences in QST across conditions. Analyses of Covariance were used to examine group (HC vs fibromyalgia) differences in QST during favorite music. Correlations were conducted to explore associations of baseline psychosocial factors with QST during favorite music. Mediation analyses were conducted to explore whether psychosocial factors contributed to greater pain sensitivity among individuals with fibromyalgia compared to HC during favorite music. RESULTS: Individuals with fibromyalgia were less sensitive to pressure pain while listening to their favorite music compared to white noise. Compared to HC, individuals with fibromyalgia reported higher baseline negative affect and lower pain thresholds and tolerances during favorite music. Negative affect partially mediated the relationship between pain status (HC vs fibromyalgia) and pain sensitivity during favorite music. CONCLUSIONS: Individuals with fibromyalgia were less pain sensitive while listening to favorite music than white noise, although they were more sensitive than HC. Greater negative affect endorsed by individuals with fibromyalgia contributed to their greater pain sensitivity. Future studies should explore the impact of favorite music on clinical pain. CLINICAL TRAILS REGISTRATION: This study was registered with ClinicalTrials.gov (NCT04087564) and began on 6/13/2019.

Does the Association Between Psychosocial Factors and Opioid Use After Elective Spine Surgery Differ by Sex in Older Adults?

Purpose: Psychosocial disorders have been linked to chronic postoperative opioid use and the development of postoperative pain. The potential interaction between sex and psychosocial factors with respect to opioid use after elective spine surgery in the elderly has not yet been evaluated. Our aim was to assess whether any observed association of anxiety or depression indicators with opioid consumption in the first 72 hours after elective spine surgery varies by sex in adults ≥65 years. Patients and Methods: Secondary analysis of a retrospective cohort of 647 elective spine surgeries performed at Brigham and Women's Hospital, July 1, 2015-March 15, 2017, in patients ≥65. Linear mixed-effects models were used to test whether history of anxiety, anxiolytic use, history of depression, and antidepressant use were associated with opioid consumption 0-24, 24-48, and 48-72 post surgery, and whether these potential associations differed by sex. Results: History of anxiety, anxiolytic use, history of depression, and antidepressant use were more common among women (51.3% of the sample). During the first 24 hours after surgery, men with a preoperative history of anxiety consumed an adjusted mean of 19.5 morphine milligram equivalents (MME) (99.6% CI: 8.1, 31.0) more than men without a history of anxiety; women with a history of anxiety only consumed an adjusted mean 2.9 MME (99.6% CI: -3.1, 8.9) more than women without a history of anxiety (P value for interaction between sex and history of anxiety <0.001). No other interactions were detected between sex and psychosocial factors with respect to opioid use after surgery. Conclusion: Secondary analysis of this retrospective cohort study found minimal evidence that the association between psychosocial factors and opioid consumption after elective spine surgery differs by sex in adults ≥65.

Daily pain and opioid administration in hospitalized patients with cancer: the importance of psychological factors, recent surgery, and current opioid use.

ABSTRACT: Pain is common and variable in its severity among hospitalized patients with cancer. Although biopsychosocial factors are well established as modulators of chronic pain, less is known about what patient-level factors are associated with worse pain outcomes among hospitalized cancer patients. This prospective cohort study included patients with active cancer presenting to the emergency department (ED) with pain severity of ≥4/10 and followed pain outcomes longitudinally throughout hospital admission. Baseline demographic, clinical, and psychological factors were assessed on ED presentation, and daily average clinical pain ratings and opioid consumption during hospitalization were abstracted. Univariable and multivariable generalized estimating equation analyses examined associations of candidate biopsychosocial, demographic, and clinical predictors with average daily pain and opioid administration. Among 113 hospitalized patients, 73% reported pain as the primary reason for presenting to the ED, 43% took outpatient opioids, and 27% had chronic pain that predated their cancer. Higher pain catastrophizing ( B = 0.1, P ≤ 0.001), more recent surgery ( B = -0.2, P ≤ 0.05), outpatient opioid use ( B = 1.4, P ≤ 0.001), and history of chronic pain before cancer diagnosis ( B = 0.8, P ≤ 0.05) were independently associated with greater average daily pain while admitted to the hospital. Higher pain catastrophizing ( B = 1.6, P ≤ 0.05), higher anxiety ( B = 3.7, P ≤ 0.05), lower depression ( B = -4.9, P ≤ 0.05), metastatic disease ( B = 16.2, P ≤ 0.05), and outpatient opioid use ( B = 32.8, P ≤ 0.001) were independently associated with higher daily opioid administration. Greater psychological distress, especially pain catastrophizing, as well as pain and opioid use history, predicted greater difficulty with pain management among hospitalized cancer patients, suggesting that early assessment of patient-level characteristics may help direct consultation for more intensive pharmacologic and nonpharmacologic interventions.

The Relationship of Postoperative Pain and Opioid Consumption to Postoperative Delirium After Spine Surgery.

Purpose: To examine the relationship between postoperative pain and opioid use and the development of postoperative delirium (POD), with attention to the preoperative opioid use status of patients. Methods: This was a secondary analysis of data from a prospective observational study of patients (N = 219; ≥70 years old) scheduled to undergo elective spine surgery. Maximal daily pain scores (0-10) and postoperative morphine milligram equivalents per hour (MME/hr) were determined for postoperative days 1-3 (D1-3). POD was assessed by daily in-person interviews using the Confusion Assessment Method and chart review. Results: Patients who reported regular preoperative opioid use (n = 58, 27%) reported significantly greater maximal daily pain scores, despite also requiring greater daily opioids (MME/hr) in the first 3 days after surgery. These patients were also more likely to develop POD. Interestingly, while postoperative pain scores were significantly higher in patients who developed POD, postoperative opioid consumption was not significantly higher in this group. Conclusion: POD was associated with greater postoperative pain, but not with postoperative opioid consumption. While postoperative opioid consumption is often blamed for delirium, these findings suggest that uncontrolled pain may actually be a more important factor, particularly among patients who are opioid tolerant. These findings underscore the importance of employing multimodal perioperative analgesic management, especially among older patients who have a predilection to developing POD and baseline tolerance to opioids.

Perioperative Sleep Disturbance Following Mastectomy: A Longitudinal Investigation of the Relationship to Pain, Opioid Use, Treatment, and Psychosocial Symptoms.

OBJECTIVES: Sleep disturbance negatively impacts the quality of life and recovery. Our objective was to evaluate the relationship between the individual patient and surgical factors with greater sleep disturbance following breast surgery. METHODS: In this prospective longitudinal study, patients completed validated measures regarding sleep disturbance, pain, opioid use, and psychological symptoms preoperatively and then 2 weeks, 6 and 12 months postoperatively. Univariable and multivariable generalized estimating equations evaluated demographic, surgical, pain, and psychological predictors of sleep disturbance during the first year after breast surgery. RESULTS: Female patients (n=259) reported varying degrees of sleep disturbance, which were longitudinally associated with pain and psychosocial factors (eg, anxiety, depression, and affect). Independent preoperative predictors of worse sleep disturbance included younger age (B=-0.09, P =0.006), opioid use (B=3.09, P =0.02), and higher pain (B=0.19, P =<0.001) and anxiety (B=0.45, P =<0.001) at baseline. In addition, higher baseline positive affect (B=-0.14, P =<0.012) and the surgical category total mastectomy without reconstruction (B=-2.81, P =<0.006) were independently associated with lower sleep disturbance. Those with worse baseline sleep required more opioid analgesics during surgical recovery, and continued use of opioids at 2 weeks postsurgery was associated with disturbed sleep. DISCUSSION: Certain patient characteristics, including younger age and baseline anxiety, positive affect, pain, and opioid use, were associated with greater sleep disturbance in the first year after breast surgery. Sleep disturbance was also associated with the greater perioperative and postoperative opioid requirements. Preoperative interventions (eg, anxiety management, cultivating positive affect, and multimodal pain management) in high-risk individuals may enhance sleep and recovery postoperatively, and allow more moderate and less prolonged opioid use.

Brief Mindfulness-Based Cognitive Behavioral Therapy is Associated with Faster Recovery in Patients Undergoing Total Knee Arthroplasty: A Pilot Clinical Trial.

OBJECTIVE: To assess whether brief mindfulness-based cognitive behavioral therapy (MBCBT) could enhance the benefits of total knee arthroplasty (TKA) in improving pain and pain-related disability. Specifically, to determine 1) whether patients who received MBCBT differed from matched controls who received treatment-as-usual with regard to postsurgical pain outcomes and 2) whether changes in pain catastrophizing, depression, or anxiety explained the potential effects of MBCBT on pain outcomes. DESIGN: Pilot clinical trial. SETTING: An academic teaching hospital serving a large urban and suburban catchment area surrounding the Boston, Massachusetts metropolitan region. SUBJECTS: Sample of 44 patients undergoing TKA. Patients who completed a brief MBCBT intervention (n = 22) were compared with age-, race-, and sex-matched controls who received treatment-as-usual (n = 22). METHODS: The MBCBT intervention included four 60-minute sessions delivered by a pain psychologist in person and via telephone during the perioperative period. Participants were assessed at baseline and at 6 weeks, 3 months, and 6 months after surgery. RESULTS: Compared with matched controls, patients who received MBCBT had lower pain severity and pain interference at 6 weeks after surgery. Group differences in outcomes were mediated by changes in pain catastrophizing but not by changes in depression or anxiety. The MBCBT group had similar reductions in pain severity and interference as the control group did at 3 and 6 months after surgery. CONCLUSIONS: This work offers evidence for a safe and flexibly delivered nonpharmacological treatment (MBCBT) to promote faster recovery from TKA and identifies change in pain catastrophizing as a mechanism by which this intervention could lead to enhanced pain-related outcomes.

Increased Clinical Pain Locations and Pain Sensitivity in Women After Breast Cancer Surgery: Influence of Aromatase Inhibitor Therapy.

OBJECTIVES: Aromatase inhibitors (AIs), which potently inhibit estrogen biosynthesis, are a standard treatment for hormone sensitive early-stage breast cancer. AIs have been associated with substantial joint pain and muscle stiffness (aromatase inhibitor-associated musculoskeletal syndrome). However, the link between AIs and number of clinical pain locations and pain sensitivity are less well understood. The aim of this study was to compare longitudinal changes in clinical pain and quantitative pain sensitivity between women who did or did not receive AI therapy. METHODS: Women with early-stage breast cancer were prospectively enrolled and assessed for clinical pain in surgical and nonsurgical body areas using the Brief Pain Inventory and Breast Cancer Pain Questionnaire, and for pain sensitivity using quantitative sensory testing preoperatively and at 1 year postoperatively. Pain outcomes between participants who did and did not begin adjuvant AI therapy were compared using Wilcoxon Signed-Ranks and generalized estimating equation linear regression analyses. RESULTS: Clinical pain and pain sensitivity were comparable between AI (n=49) and no-AI (n=106) groups preoperatively. After adjusting for body mass index, AI therapy was associated with a greater increase in the number of painful nonsurgical body sites (significant time by treatment interaction, P =0.024). Pain location was most frequent in knees (28%), lower back (26%), and ankles/feet (17%). Quantitative sensory testing revealed a significant decrease in pain sensitivity (increased pressure pain threshold) in the no-AI group over time, but not in the AI group. CONCLUSIONS: AI therapy was associated with increased diffuse joint-related pain and greater post-treatment pain sensitivity, potentially implicating central sensitization as a contributing pain mechanism of aromatase inhibitor-associated musculoskeletal syndrome worthy of future investigation.

Early postoperative psychological distress as a mediator of subsequent persistent postsurgical pain outcomes among younger breast cancer patients.

PURPOSE: Younger age is a risk factor for worse pain outcomes following breast cancer surgery, yet little is known about how younger women's psychological state may contribute to their pain experience. Using prospectively collected longitudinal data from a surgical cohort, we examined whether early postoperative psychological distress at 2 weeks mediated the association between younger age and subsequent worse pain-related functioning 3 months after surgery. METHODS: Patients (N = 159) were recruited before breast cancer surgery into this longitudinal cohort study. Age at time of surgery, psychological distress (anxiety, depression, and sleep disturbance) assessed 2 weeks postoperatively, and impact of surgical pain on cognitive/emotional functioning and physical functioning assessed 3 months postoperatively were used for analysis. RESULTS: Younger age was associated with greater depression, anxiety, and sleep disturbance 2 weeks postoperatively. Younger age was also associated with greater ratings of pain impacting cognitive/emotional functioning and physical functioning 3 months postoperatively. The association between younger age and worse cognitive/emotional impact of pain was mediated by greater anxiety and sleep disturbance. Similarly, the association between younger age and worse physical impact of pain was mediated by greater sleep disturbance. CONCLUSION: The degree of anxiety and sleep disturbance that occur early after breast surgery may contribute to greater chronic pain-related functional disability among younger patients. Anxiety and sleep disturbance are modifiable with behavioral interventions, making them potential perioperative targets to improve long-term outcomes in young breast cancer survivors.

Increased pain catastrophizing longitudinally predicts worsened pain severity and interference in patients with chronic pain and cancer: A collaborative health outcomes information registry study (CHOIR).

OBJECTIVE: Little is known about how changes in psychosocial factors impact changes in pain outcomes among patients with cancer and chronic pain. This longitudinal cohort study of cancer patients investigated the relationships between changes in psychosocial factors and changes in pain severity and interference over time. METHODS: Data from patients with cancer and chronic pain (n = 316) treated at a tertiary pain clinic were prospectively collected. At their baseline visit (Time 1), patients provided demographic and clinical information, and completed validated psychosocial and pain assessments. Psychosocial and pain assessments were repeated at a follow-up visit (Time 2), on average 4.9 months later. Change scores (Time 2-Time 1) were computed for psychosocial and pain variables. Multivariable hierarchical linear regressions assessed the associations between changes in psychosocial factors with changes in pain outcomes over time. RESULTS: Participants were an average age of 59 years, were 61% female, and 69% White. Overall, a decrease in pain severity (p ≤ 0.001), but not pain interference, was observed among the group over time. In multivariable analyses, increased pain catastrophizing was significantly associated with increased pain severity over time (ß = 0.24, p ≤ 0.001). Similarly, increased pain catastrophizing (ß = 0.21, p ≤ 0.001) and increased depression (ß = 0.20, p ≤ 0.003) were significantly associated with increased pain interference over time. Demographic and clinical characteristics were not significantly related to changes in pain outcomes. CONCLUSIONS: Increased pain catastrophizing was uniquely associated with increased chronic pain severity and interference. Our findings indicate that cancer patients with chronic pain would likely benefit from the incorporation of nonpharmacological interventions, simultaneously addressing pain and psychological symptoms.

Psychological Evaluation of Patients With Cancer Presenting to the Emergency Department With Pain: Independent Predictors of Worse Pain Severity, Interference, and Higher Hourly Opioid Administration.

PURPOSE: Pain is a common complaint in patients with cancer presenting to the emergency department (ED). This prospective study evaluated whether biopsychosocial factors could help predict cancer patients with risk of higher pain severity, pain interference, and opioid consumption. METHODS: Patients with cancer presenting to the ED with a complaint of moderate-severe pain (≥ 4/10-numeric rating scale) completed validated self-report measures assessing sociodemographics, cancer-related treatments, pain severity and interference, medication use, and psychological symptoms (depression, anxiety, pain catastrophizing, and sleep disturbance). Opioids administered and subsequent hospitalization were abstracted. Univariable and multivariable regression analyses assessed factors associated with pain-related outcomes. RESULTS: Participants (n = 175) presented with a variety of cancer types, with 76% having metastatic disease and 42% reporting current outpatient opioid use. Higher pain catastrophizing, lower depressive symptoms, lower income, outpatient opioid use, and historical chronic pain were independently associated with worse pain (P ≤ .05). Higher pain catastrophizing, anxiety, sleep disturbance, outpatient opioid use, and education were independently associated with worse pain interference (P ≤ .05). The sole independent predictor of ED opioid administration was outpatient opioid use. Patients taking outpatient opioids were younger, had lower health literacy, worse pain catastrophizing, sleep disturbance, depression/anxiety, and greater rates of metastatic cancer and cancer-related surgery (P ≤ .05). CONCLUSION: Biopsychosocial factors, particularly pain catastrophizing, remained significantly associated with worse pain outcomes for patients with cancer in the ED even after controlling for demographic and clinical variables. Patient outpatient opioid use was independently associated with worse pain, interference, and greater opioid administration, identifying this as a marker for who may benefit most from adjuvant pharmacologic and behavioral interventions.

Applying the Rapid OPPERA Algorithm to Predict Persistent Pain Outcomes Among a Cohort of Women Undergoing Breast Cancer Surgery.

Persistent postmastectomy pain after breast surgery is variable in duration and severity across patients, due in part to interindividual variability in pain processing. The Rapid OPPERA Algorithm (ROPA) empirically identified 3 clusters of patients with different risk of chronic pain based on 4 key psychophysical and psychosocial characteristics. We aimed to test this type of group-based clustering within in a perioperative cohort undergoing breast surgery to investigate differences in postsurgical pain outcomes. Women (N = 228) scheduled for breast cancer surgery were prospectively enrolled in a longitudinal observational study. Pressure pain threshold (PPT), anxiety, depression, and somatization were assessed preoperatively. At 2-weeks, 3, 6, and 12-months after surgery, patients reported surgical area pain severity, impact of pain on cognitive/emotional and physical functioning, and pain catastrophizing. The ROPA clustering, which used patients' preoperative anxiety, depression, somatization, and PPT scores, assigned patients to 3 groups: Adaptive (low psychosocial scores, high PPT), Pain Sensitive (moderate psychosocial scores, low PPT), and Global Symptoms (high psychosocial scores, moderate PPT). The Global Symptoms cluster, compared to other clusters, reported significantly worse persistent pain outcomes following surgery. Findings suggest that patient characteristic-based clustering algorithms, like ROPA, may generalize across diverse diagnoses and clinical settings, indicating the importance of "person type" in understanding pain variability. PERSPECTIVE: This article presents the practical translation of a previously developed patient clustering solution, based within a chronic pain cohort, to a perioperative cohort of women undergoing breast cancer surgery. Such preoperative characterization could potentially help clinicians apply personalized interventions based on predictions concerning postsurgical pain.

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

INTRODUCTION: Early diagnosis of acute extremity compartment syndrome is crucial to timely surgical management. Pain is commonly used as an early diagnostic sign for acute extremity compartment syndrome, making regional anesthesia after lower extremity surgery controversial. This randomized study tested whether different concentrations of local anesthetics, or combinations of nerve blocks, would differentially impact the perception of acute extremity compartment syndrome-like pressure and ischemic pain. METHODS: Healthy volunteers underwent quantitative sensory testing, including determination of pressure pain thresholds and prolonged pressure/ischemic pain in the leg using a variable cuff inflation system. Subjects were randomized to receive (1) adductor canal block alone (ACB), (2) ACB with low-concentration sciatic nerve block (ACB +LC SNB), or (3) ACB with high-concentration SNB (ACB +HC SNB). For the primary outcome, we assessed block-induced increases in pressure threshold to reach 6/10 pain, and compared the degree of increase between the three groups. The main secondary outcome was a comparison of average pain score during a 5 min hold at the 6/10 pressure pain threshold between the three groups. RESULTS: All blocks raised pressure pain threshold and decreased ischemic pain, but to variable extents. Specifically, the amount the block increased pressure pain threshold was significantly different among ACB, ACB+LC SNB, and ACB+HC SNB groups (mean±SD: 24±32 mm Hg, 120±103 mm Hg, 159±93 mm Hg; p=0.002), with post hoc testing revealing ACB as less than the other two groups. Similarly, average pain scores during a prolonged/ischemic cuff hold differed among the groups (4.2±1.4, 1.4±1.7, 0.4±0.7; p<0.001), with post hoc testing revealing ACB as significantly higher. DISCUSSION: This study suggests the possible utility of titrating regional anesthesia, to provide some analgesia while still allowing acute extremity compartment syndrome detection. TRIAL REGISTRATION NUMBER: NCT04113954.

Pain, numbness, or both? Distinguishing the longitudinal course and predictors of positive, painful neuropathic features vs numbness after breast cancer surgery.

INTRODUCTION: Both positive (burning, stabbing, and allodynia) and negative (numbness) neuropathic symptoms may arise after surgery but likely contribute differently to patients' postoperative pain experience. Numbness has been identified as divergent from positive neuropathic symptoms and therefore excluded from some neuropathic assessment tools (Neuropathic Pain Scale for PostSurgical patients [NeuPPS]). OBJECTIVES: In this prospective longitudinal study of patients undergoing breast surgery, we aimed to delineate the time course of numbness and its coincidence with NeuPPS and to contrast the association of surgical, psychosocial, and psychophysical predictors with the development of negative vs positive neuropathic symptoms. METHODS: Patients reported surgical area sensory disturbances at 2 weeks and 3, 6, and 12 months postoperatively. Association of baseline demographic, surgical, psychosocial, and psychophysical factors with NeuPPS and numbness across time was investigated using generalized estimating equation linear and logistic regression. RESULTS: Numbness was consistently reported by 65% of patients; positive neuropathic symptoms were less common, often decreasing over time. Neuropathic Pain scale for PostSurgical patients and numbness co-occurred in half of patients and were both associated with greater clinical pain severity and impact, younger age, axillary surgery, and psychosocial factors. More extensive surgery and chemotherapy were only associated with numbness. Conversely, other chronic pain, lower physical activity, perioperative opioid use, negative affect, and lower baseline pressure pain threshold and tolerance were only associated with NeuPPS. Patients reporting numbness alone did not endorse substantial clinical pain. CONCLUSIONS: Differentiation of predictors, prevalence, and time course of numbness vs NeuPPS in breast surgical patients revealed important distinctions, suggesting that their independent assessment is worthwhile in future studies of postsurgical pain.