Acute and Chronic Pain after Surgery: Risk Factors and Preventive Strategies
Dominique Fletcher, MD, PhD (France), Joel Katz, PhD (Canada), Esther Pogatzki-Zahn, Prof. Dr. med. (Germany)
Inadequate postoperative pain management leads to poor recovery, reduced quality of life and fosters the development of disabling chronic pain. In the present workshop we will address these issues, mainly by using data from two large acute pain registry projects, PAIN OUT (www.pain-out.eu) and QUIPS with more than 400.000 data sets in total. In the first talk, we show that pain scores after different types of surgical procedures are often higher than expected, e.g. after 'minor' procedures. Furthermore, variation of care and outcome throughout different countries will be demonstrated and the problem of chronic pain after surgery will be addressed. The second talk will focus on risk factors for the development of severe acute and chronic pain after surgery including stratification of these factors by using the registry data (PAIN OUT and QUIPS). The third talk will give a comprehensive overview about therapeutic options for preventing chronic pain after surgery.
Classifying Chronic Pain in ICD-11 for Clinical Practice and Research
Stein Kaasa, MD, PhD (Norway), Winfried Rief, Ph.D. (Germany), Joachim Scholz, MD (United States)
An adequate classification system for chronic pain is the essential basis for optimized treatment decisions, health care, research activities, and public interest for people with chronic pain. However, the current systems like the worldwide used ICD-10 suffer from serious shortcomings. Therefore, IASP has introduced a working group 'Chronic Pain Classification in ICD-11', which was approved by WHO, and which offered a general pain classification proposal (Treede et al 2015; PAIN). Winfried Rief (Germany) will present the rationale and structure of the chronic pain classification system, while Stein Kaasa (Norway) will exemplify the classification system for chronic cancer pain conditions. Joachim Scholz (US) will summarize the diagnoses for neuropathic pain, and how they are based on empirical evidence. Participants are invited to contribute to the ongoing process, before the World Medical Assembly will decide about ICD-11.
Great Expectations or Real Physiological Effects: What Is Underlying Analgesia Induced by Sham and Real Acupuncture?
Kenji Kawakita, PhD (Japan), Jian Kong, (United States), Zhen Zheng, (Australia)
Acupuncture is increasingly being used as a cost-effective and safe treatment for pain disorders. Clinical trials have yielded contradictory results. Some studies find that acupuncture produces significant clinical improvements when compared with no treatment or guideline-based standard care. Others indicate that acupuncture's specific effect is relatively small when compared with placebo/sham, suggesting that non-specific (placebo) effects are important contributors to acupuncture's therapeutic results. The lack of a clear mechanism of action to explain the benefit of placebo/sham acupuncture has significantly hindered attempts to incorporate this promising therapy into the current medical system. In this talk, we will examine the neurophysiological and psychophysical factors that contribute to the effects of sham acupuncture. The factors include those at the peripheral and central nervous system levels, types of pain, and individuals' pain adaptability.
Knowledge Translation in Pain Research: The Push and the Pull
Fiona Blyth, PhD, MBBS (Australia), Mary Cardosa, MBBS (Malaysia), Amanda Williams, PhD (United Kingdom)
The evidence base generated by pain research is increasing exponentially, but we continue to see substantial failures in translation of findings into patient care and health policy, to the detriment of people with pain. This workshop will focus on pain knowledge translation, defined as 'ensuring that stakeholders are aware of and use research evidence to inform ... health and healthcare decision-making' (1). The impetus may come from 'push' by researchers, for example by synthesis of research findings in systematic reviews, or from 'pull' factors, where policy-makers, clinician groups, and health service administrators actively seek evidence to inform decision-making (2).In this workshop we will assess the progress of knowledge translation in pain research, using case studies across the knowledge translation spectrum illustrating 'push' and 'pull' factors in different countries and cultural settings. (1)Grimshaw et al ,Implementation Science 2012;(2) Campbell, Evidence & Policy 2011.
Making the Most of Your Data and Understanding the Literature : Sorting Out SNP Association, Gene-Based Tests, and Pathway Analyses Related to Chronic Pain
Alban Latremoliere, (United States), Roy Levitt, MD (United States), Frances Williams, BSc MBBS PhD (United Kingdom)
The literature is replete with publications about 'candidate genes' showing an association between single SNPs within and nearby genes suggesting a causal relationship. In many cases, large-scale phenotype-genotype studies are not always practical to provide sufficient power to detect association with rare variants. Gene-based analyses provide methods that 'pool' rare variants in a single gene that may provide additional power to detect association with complex pain phenotypes. Additionally, pathway analyses can further assess for rare variants in functionally related genes, providing added power. These methods may be applicable to existing datasets. In this session we will cover their application to demonstrate the practical importance in identifying 'pain genes' across populations, species, and different persistent pain phenotypes to provide new insights to that help prevent 'throwing the baby out with the statistical bathwater'.
Mechanisms of Neuropathic Pain: Plasticity and Opportunities for Disease Modification
Ichiro Nishimura, (United States), Theodore Price, PhD (United States), Hiroshi Ueda, PhD (Japan)
Neuropathic pain is linked to changes in the function and phenotype of nociceptors and glia. The symposium will focus on mechanisms through which this peripheral plasticity occurs and how these mechanisms can be targeted to achieve disease modification. Dr. Price will focus on how nerve injury causes alterations in translation regulation and other metabolic pathways in dorsal root ganglion (DRG) neurons and how this can be modified by AMPK activators. He will also discuss recent RNA-seq findings from human DRG, including DRG from humans with neuropathic pain and how this work reveals new insight into neuropathic pain. Dr. Ueda will discuss lysophospholipid (LPA) receptors as key mediators of DRG and glial plasticity after nerve injury and how this signaling axis can lead to disease modifying opportunities for therapeutics. Finally, Dr. Nishimura will bring a bio-engineering approach to manipulating Nav1.8 expression and localization in injured nociceptors to manipulate excitability.
Neuropathic Pain after Spinal Cord Injury: Facilitating the Development of Novel Therapeutics by Characterizing Pain Types in the Clinic and in Experimental Animal Models
Nanna Finnerup, MD (Denmark), Wenlong Huang, PhD, MBBS (United Kingdom), Julian Taylor, PhD (United Kingdom)
Neuropathic pain is a prevalent complication of spinal cord injury (SCI). Although more than two thirds of patients with SCI suffer from different types of pain, available pharmacological treatment strategies are limited. Recently the classification of SCI neuropathic pain has been updated and a concerted effort to identify important pain types has been initiated. Recommendations for the pharmacological treatment of SCI neuropathic pain could improve by recognizing different pain phenotypes, focusing particularly on affective pain and restoration of endogenous pain modulation (EPM). This strategy is now being employed in animal models of spinal cord injury by assessing complex behavioural and biomarker assessment within the anterior cingulate, and EPM dysfunction. Comprehensive in vitro and in vivo experimental screening of novel therapeutics, including omega-3 and 9 fatty acids, and the use of better experimental designs will facilitate the development of effective treatments.
Recent Developments in the Use of Non-Verbal Indicators of Pain in Dementia
Michael Farrell, PhD (Australia), Miriam Kunz, (Netherlands), Stefan Lautenbacher, PhD (Germany)
The prevalence of patients with dementia is rapidly increasing and hereby those with too impaired verbal skills to communicate pain. Thus, non-verbal alternative pain measures are required. Unfortunately, there is little agreement which exact behavioral items and which methods of assessment are best pain indicative. Recently, empirical attempts have multiplied to sort out these behavioral indicators, which allow assessing pain with high accuracy in a time-economical fashion. The behavioral domain, which promises best-indicative results for pain, is the facial expression. Fundamental research on the facial expression has inspired new assessment techniques, which may soon result in automatic pain face reading. The undisputed method of choice to illuminate the pathophysiology of pain processing is still fMRT. This method can show the cerebral spread of the 'pain matrix' in the course of dementia; coherence analysis also allows for determining the interaction between cognition and pain.
Small Fiber Pathology: Diagnostic Approaches and Pathophysiology of a Frequent Finding in Diverse Painful Conditions
Rayaz Malik, (Qatar), Maria Nolano, MD, PhD (Italy), Nurcan Üçeyler, MD (Germany)
Small fiber neuropathies (SFN) are a subgroup of sensory neuropathies that present with burning pain at toes and feet. Small fiber pathology (SFP) is increasingly described in many different painful conditions that are distinct from SFN, but share multidimensional impairment of small nerve fibers. In our workshop we intend to summarize current knowledge on SFP in different painful conditions and to inform the audience about the current possibilities and limits of an established (skin biopsy) and new (corneal confocal microscopy) diagnostic tool in the assessment of small fibers. We will discuss pathophysiological mechanisms that may underlie SFP in diverse painful disorders and focus on the two controversial entities of SFN and the fibromyalgia syndrome. The workshop aims to update the knowledge of the participants in understanding the mechanisms underlying SFP and to guide the audience into the exciting field of clinical and experimental small fiber research.
Using Current Evidence to Support Preclinical and Clinical Studies of Neuropathic Pain to Better Inform Each Other
Nick Andrews, PhD (United States), Emily Sena, PhD (United Kingdom), Rachel Wodarski, PhD (United Kingdom)
Biomedical research is an incremental process in which the findings from one experiment inform, and are challenged or supported by, future experiments. Animal models of neuropathic pain are generally performed to inform human health. During this session we will present data describing the conduct and reporting of animal experiments, past and future, in comparison to clinical trials, to suggest how these two research domains may better inform each other. We will use chemotherapy-induced peripheral neuropathy as a worked example, presenting data from reviews of both preclinical and clinical studies. We will also use lessons from phase-III clinical trials to inform similar large-scale multi-centre studies to be performed in animal studies.