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Truncal blocks and teenager postoperative pain perception after laparoscopic surgical procedures.

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Placebo and nocebo effects and operant pain-related avoidance learning.

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Ubrogepant for the Treatment of Migraine.

Ubrogepant is an oral, small-molecule calcitonin gene-related peptide receptor antagonist for acute migraine treatment.

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Efficacy of Interpretation Bias Modification in Patients with Chronic Pain.

Patients with chronic pain demonstrate interpretational bias to pain and models of pain suggest interpretational bias affects subsequent pain experience. This study developed an interpretation bias modification for pain (IBM-P) and examined its efficacy. A total of 48 patients with chronic pain were recruited and randomly assigned to either the training group (n = 24) or the control group (n = 24). Interpretational bias, negative emotions, and attentional bias to pain-related stimuli were assessed before and after conducting IBM-P. The main results indicated that the training group showed less interpretational bias and negative emotions after IBM-P than the control group. The training group also gazed at neutral words longer than at "new" affective pain words after IBM-P than they did prior to the intervention. Furthermore, significant mediating effects of post-interpretational bias were found in the relationship between the group type and post-negative emotions and post-dwell time bias. These results suggest that IBM-P can modify interpretational bias which leads to changes in negative emotions and attentional bias. Future research is needed to confirm the effect of modifying interpretational bias and its clinical utility in the field of pain management. Perspective: This article investigated the efficacy of IBM-P and suggested that modifying interpretational bias is followed by changes in negative emotions and attentional bias. These findings may help health professionals understand the role of interpretational bias in chronic pain and encourage the potential use of IBM in pain management.

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Addition of Slowly Repeated Evoked Pain Responses to Clinical Symptoms Enhances Fibromyalgia Diagnostic Accuracy.

Fibromyalgia is a chronic pain syndrome characterized by central sensitization. A novel protocol based on slowly repeated evoked pain (SREP) appears to be a useful marker of pain sensitization in fibromyalgia patients. Whether SREP enhances diagnostic accuracy beyond key clinical symptoms that characterize fibromyalgia has not been examined.

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Perturbing the activity of the superior temporal gyrus during pain encoding prevents the exaggeration of pain memories: a virtual lesion study using single-pulse transcranial magnetic stimulation.

Past studies have shown that pain memories are often inaccurate, a phenomenon known as mnemonic pain bias. Pain memories are thought to play an important role on how future pain is felt. Recent evidence from our laboratory suggests that individuals who exaggerate past pain display increased superior temporal gyrus (STG) and parahippocampal gyrus (PHG) activity during the encoding of experimental painful stimulations, suggesting that these brain structures play an important role in pain memories.

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Adverse Childhood Experiences Increase Risk for Prescription Opioid Misuse.

The United States is in the midst of an opioid overdose epidemic, with a significant portion of the burden associated with prescription opioids. In response, the CDC released a Guideline for Prescribing Opioids for Chronic Pain, which promotes access to treatment for opioid use disorder. Decades of research have linked childhood adversity to negative health and risk behavior outcomes, including substance misuse. Our present study builds upon this work to examine the relationship between adverse childhood experiences (ACEs) and prescription opioid misuse. We compiled data from the Behavioral Risk Factor Surveillance System implemented by Montana and Florida in 2010 and 2011, respectively. Logistic regressions (run in 2017) tested the associations between ACEs and subsequent prescription pain medicine/opioid misuse outcomes in adulthood. ACEs were prevalent, with 62.7% of respondents in Montana and 50% in Florida reporting at least one ACE. The presence of ACEs was positively associated with prescription opioid misuse across both samples. Respondents reporting three or more ACEs had increased odds of taking opioids more than prescribed, without a prescription, and for the feeling they cause. Our results support a strong link between ACEs and prescription opioid misuse. Opportunities to prevent opioid misuse start with assuring safe, stable, nurturing relationships and environments in childhood and across the lifespan to prevent ACEs from occurring, and intervening appropriately when they do occur. Substance use prevention programs for adolescents, appropriate pain management and opioid prescribing protocols, and treatments for opioid use disorder can address ACEs by enhancing treatment safety and effectiveness and can reduce the intergenerational continuity of early adversity.

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CRPS is not associated with altered sensorimotor cortex GABA or glutamate.

Complex regional pain syndrome (CRPS) is a debilitating chronic pain disorder typically in the upper or lower limbs. Whilst CRPS usually develops from a peripheral event, it is likely maintained by central nervous system changes. Indeed CRPS is reported to be associated with sensorimotor cortex changes, or functional 'reorganisation', as well as deficits such as poor tactile acuity. Whilst the mechanisms underpinning cortical reorganisation in CRPS are unknown, some have hypothesised that it involves disinhibition, i.e. a reduction in gamma-Aminobutyric acid (GABA) activity. In this study we addressed this hypothesis by using edited magnetic resonance spectroscopy (MRS) to determine sensorimotor GABA and glutamate concentrations in 16 humans with CRPS and 30 matched controls and the relationship of these concentrations with tactile acuity. We found that individuals with upper limb CRPS displayed reduced tactile acuity in the painful hand compared with the non-painful hand and pain-free controls. Despite this acuity deficit, CRPS was not associated with altered GABA or glutamate concentrations within the sensorimotor cortex on either the side that represents the affected or unaffected hand. Furthermore, there was no significant relationship between sensorimotor GABA or glutamate concentrations and tactile acuity in CRPS or control subjects. Although our sample was small, these data suggest that CRPS is not associated with altered total sensorimotor GABA or glutamate concentrations. Whilst these results are at odds with the sensorimotor cortex disinhibition hypothesis, it is possible that GABAergic mechanisms other than total GABA concentration may contribute to such disinhibition. Complex regional pain syndrome is a debilitating chronic pain disorder that usually affects the limbs. It is associated with altered sensorimotor cortex function including reorganisation and reduced tactile acuity, which are thought to result from reduced on-going inhibition. However, we found that this pain condition is not associated with reduced on-going sensorimotor inhibition in the form of gamma-Aminobutyric acid concentration, the major inhibitory neurotransmitter in the brain. These findings strongly suggest that changes in sensorimotor function in individuals with complex regional pain syndrome are explained by factors other than neurotransmitter concentration.

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OPRM1 and COMT polymorphisms: implications on postoperative acute, chronic and experimental pain after cardiac surgery.

Investigate the potential role of (mu-opioid receptor) and (catechol-O-methyltransferase enzyme) polymorphisms in postoperative acute, chronic and experimental thermal pain. A secondary analysis of 125 adult cardiac surgery patients that were randomized between fentanyl and remifentanil during surgery and genotyped. Patients in the fentanyl group with the high-pain sensitivity haplotype required less postoperative morphine compared with the average-pain sensitivity haplotype (19.4 [16.5; 23.0] vs 34.6 [26.2; 41.4]; p = 0.00768), but not to the low-pain sensitivity group (30.1 [19.1; 37.7]; p = 0.13). No association was found between haplotype and other pain outcomes or polymorphisms and the different pain modalities. haplotype appears to explain part of the variability in acute postoperative pain in adult cardiac surgery patients.

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Postoperative Pain and Analgesic Requirements in the First Year after Intraoperative Methadone for Complex Spine and Cardiac Surgery.

Methadone is a long-acting opioid that has been reported to reduce postoperative pain scores and analgesic requirements and may attenuate development of chronic postsurgical pain. The aim of this secondary analysis of two previous trials was to follow up with patients who had received a single intraoperative dose of either methadone or traditional opioids for complex spine or cardiac surgical procedures.

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