- Email: [email protected]
53 EXPERIMENTAL STUDIES IN HEALTHY HUMANS
S24
Oral Presentations / European Journal of Pain 13 (2009) S1–S54
53 EXPERIMENTAL STUDIES IN HEALTHY HUMANS A. Mouraux *. Universit´e Catholique de Louvain, Brussels, Belgium Nociception starts with the activation of Ad and C nociceptors. However, for the conscious experience of pain to emerge from nociception, cortical processing of this nociceptive input seems mandatory. Furthermore, the cortex, through its descending projections, modulates the transmission and processing of ascending nociceptive input within the spinal dorsal horn, brainstem and subcortical structures. In recent years, research on the cortical and subcortical mechanisms modulating pain perception has become a major focus of neuroscience. Indeed, it is now widely recognized that the experience of pain is not only determined by the physical characteristics of the eliciting nociceptive stimulus, but also by autonomous, cognitive and affective factors. In this review, I will examine the advantages but also the limitations of non-invasive functional neuroimaging methods (in particular, functional magnetic resonance imaging and electroencephalography) and how they may contribute to explore the interplay of these factors in humans, both at cortical and subcortical levels with special attention for the concept of the so-called “pain matrix”.
benchmarking project, QUIPS and the IASP Task Force “International Pain Registry”. PAIN-OUT is funded by the 7th EU Framework Program, it is a 4 year program, starting January 2009, with 16 participating sites across Europe. PAIN-OUT will provide the medical community with a noncommercial, web-based, user-friendly system to improve treatment of patients with postoperative pain. PAIN-OUT will feature three principal functions which are based on a large Pain Registry: • Feedback and benchmarking system which provides participating sites with continuously updating patient data and analyses about the quality of care they currently provide compared to their performance in the past and that of other participating institutions. This allows identification of ‘best clinical practice’; • Clinical Decision Support System for Post-Operative Pain, which responds to queries made by physicians for advice regarding treatment of individual patients; • Knowledge Library which provides clinicians with easily accessible and updated, summaries of evidence-based recommendations tailored to specific post-operative situations (Fig. 1). Once these tool will be developed, participation will be open to all interested clinical sites in Europe and internationally.
54 STUDIES IN PATIENTS D. Yarnitsky *. Dept of Neurology Rambam Medical Center Technion Faculty of Medicine, Haifa, Israel Psychophysical tests of endogenous pain controlling systems had been applied in several pain disorders. Studies have shown a less efficient DNIC-like function in patients with idiopathic pain syndromes, such as tension headache, fibromyalgia, irritable bowel syndrome etc. Tests were applied either at pain site or remote from it, and represent a systemically deranged pain modulation. These fidnings raised the question of whether this dysfunction is primary to the pain syndrome, or, alternatively, caused by it. Some evidence is now available to support the first option: 1. Several studies have shown a correlation between psychophysical pain parameters such as pain threshold and magnitude estimation of experimental suprathreshold pain stimuli, obtained before surgery, and acute post operative pain. 2. One study showing correlation between DNIC-like efficiency before surgery and chronic post operative pain in thoracotomy patients. These studies support the thinking that deranged pain processing, specifically non efficient DNIC, make the subject susceptible to acquire pain. In support of the alternative is the report on improvement of DNIC efficiency after surgical treatment of painful joint disease that relieved pain. This suggests that DNIC reacts to the clinical pain state, rather than be involved in its generation. New data available along these lines will be presented and the issue of chicken and egg between pain inhibitory modulation state and prevalence of clinical pain will be discussed. In addition, findings on changes in endogenous pain inhibitory function and dysfunction in neuropathic pain patients will be presented and discussed in relation to therapeutic considerations.
Figure 1: Project overview.
Topical Seminar: PAIN-OUT – A European network project for optimizing acute pain management 55 PAIN-OUT: INTRODUCING THE CONCEPT R. Zaslansky *. Friedrich-Schiller-Universit¨ at Jena Klinik f¨ ur An¨ asthesiologie und Intensivtherapie, Jena, Germany The objective of PAIN-OUT is to develop and to validate a system for measuring quality of clinical care, providing feedback to clinicians and providing support for decision making in the field of postoperative pain management. It is based on the German
Figure 2: Sites participating in the project. Clinical sites from which data will be acquired (blue dots) and sites involved in development of methodology for the project, PAIN-OUT Pilot (red dots).
Oral Presentations / European Journal of Pain 13 (2009) S1–S54
53 EXPERIMENTAL STUDIES IN HEALTHY HUMANS A. Mouraux *. Universit´e Catholique de Louvain, Brussels, Belgium Nociception starts with the activation of Ad and C nociceptors. However, for the conscious experience of pain to emerge from nociception, cortical processing of this nociceptive input seems mandatory. Furthermore, the cortex, through its descending projections, modulates the transmission and processing of ascending nociceptive input within the spinal dorsal horn, brainstem and subcortical structures. In recent years, research on the cortical and subcortical mechanisms modulating pain perception has become a major focus of neuroscience. Indeed, it is now widely recognized that the experience of pain is not only determined by the physical characteristics of the eliciting nociceptive stimulus, but also by autonomous, cognitive and affective factors. In this review, I will examine the advantages but also the limitations of non-invasive functional neuroimaging methods (in particular, functional magnetic resonance imaging and electroencephalography) and how they may contribute to explore the interplay of these factors in humans, both at cortical and subcortical levels with special attention for the concept of the so-called “pain matrix”.
benchmarking project, QUIPS and the IASP Task Force “International Pain Registry”. PAIN-OUT is funded by the 7th EU Framework Program, it is a 4 year program, starting January 2009, with 16 participating sites across Europe. PAIN-OUT will provide the medical community with a noncommercial, web-based, user-friendly system to improve treatment of patients with postoperative pain. PAIN-OUT will feature three principal functions which are based on a large Pain Registry: • Feedback and benchmarking system which provides participating sites with continuously updating patient data and analyses about the quality of care they currently provide compared to their performance in the past and that of other participating institutions. This allows identification of ‘best clinical practice’; • Clinical Decision Support System for Post-Operative Pain, which responds to queries made by physicians for advice regarding treatment of individual patients; • Knowledge Library which provides clinicians with easily accessible and updated, summaries of evidence-based recommendations tailored to specific post-operative situations (Fig. 1). Once these tool will be developed, participation will be open to all interested clinical sites in Europe and internationally.
54 STUDIES IN PATIENTS D. Yarnitsky *. Dept of Neurology Rambam Medical Center Technion Faculty of Medicine, Haifa, Israel Psychophysical tests of endogenous pain controlling systems had been applied in several pain disorders. Studies have shown a less efficient DNIC-like function in patients with idiopathic pain syndromes, such as tension headache, fibromyalgia, irritable bowel syndrome etc. Tests were applied either at pain site or remote from it, and represent a systemically deranged pain modulation. These fidnings raised the question of whether this dysfunction is primary to the pain syndrome, or, alternatively, caused by it. Some evidence is now available to support the first option: 1. Several studies have shown a correlation between psychophysical pain parameters such as pain threshold and magnitude estimation of experimental suprathreshold pain stimuli, obtained before surgery, and acute post operative pain. 2. One study showing correlation between DNIC-like efficiency before surgery and chronic post operative pain in thoracotomy patients. These studies support the thinking that deranged pain processing, specifically non efficient DNIC, make the subject susceptible to acquire pain. In support of the alternative is the report on improvement of DNIC efficiency after surgical treatment of painful joint disease that relieved pain. This suggests that DNIC reacts to the clinical pain state, rather than be involved in its generation. New data available along these lines will be presented and the issue of chicken and egg between pain inhibitory modulation state and prevalence of clinical pain will be discussed. In addition, findings on changes in endogenous pain inhibitory function and dysfunction in neuropathic pain patients will be presented and discussed in relation to therapeutic considerations.
Figure 1: Project overview.
Topical Seminar: PAIN-OUT – A European network project for optimizing acute pain management 55 PAIN-OUT: INTRODUCING THE CONCEPT R. Zaslansky *. Friedrich-Schiller-Universit¨ at Jena Klinik f¨ ur An¨ asthesiologie und Intensivtherapie, Jena, Germany The objective of PAIN-OUT is to develop and to validate a system for measuring quality of clinical care, providing feedback to clinicians and providing support for decision making in the field of postoperative pain management. It is based on the German
Figure 2: Sites participating in the project. Clinical sites from which data will be acquired (blue dots) and sites involved in development of methodology for the project, PAIN-OUT Pilot (red dots).