Professor ZHANG Wei-hua's clinical experience in chronic somatic pain treated with zhidong needling techniques / 中国针灸

The paper summarizes professor ZHANG Wei-hua's clinical experience for the treatment of chronic somatic pain with zhidong needling techniques. In terms of the characteristics of chronic somatic pain, professor ZHANG has integrated zhidong needling with acupuncture kinetic therapy. The satisfactory therapeutic effects are obtained by selecting the painful points and regions as the treatment sites and the specific techniques of zhidong needling depending on the size of affected area, the depth of illness, the size and shape of the cord-like muscle, etc. Five techniques of zhidong needling are used accordingly with twirling, pulling, lifting and thrusting, surrounding needling methods involved, as well as with the manipulation speed, direction and frequency considered.

Scorpion venom component: AGAP exhibits local anaesthetic effects and attenuates nociceptive pain

The incidences of systemic toxicity and other complications associated with existing local anaesthetics can occur at clinical concentration level and vary with the anaesthetic techniques, types of surgery and patient factors. This evidence suggests the need for therapeutic interventions in peripheral and regional anaesthesia. Buthus martensii Karsch (BmK) scorpion venom is a compound that contains mixtures of peptides that have analgesic properties. This study aimed to investigate the local anaesthetic activity of scorpion venom peptide, AGAP (analgesic-antitumor peptide) in mechanical hyperalgesia or acute inflammatory pain. Method: Formalin was injected into the left hind paw after 20 minutes of infiltration of drugs. The time of licking or flinching of the injected hind paw was recorded as indicative of nociceptive or acute inflammatory pain. Paw flinching or quick withdrawal was considered a positive response to pain in the partial sciatic nerve ligation. The paw-withdrawal threshold (PWT) was determined by consecutively increasing and decreasing the magnitude of the stimulus. Results: The results indicated that AGAP exhibited a 67.9% inhibition in licking or flinching time and an 88.1% inhibition in paw withdrawal in mechanical hyperalgesia. The addition of AGAP to lidocaine showed an 89.5% inhibition in paw withdrawal. Conclusion: The data presented in this study suggest that local infiltration of AGAP significantly reduced mechanical hyperalgesia and acute inflammatory pain

Nociceptive Profile and Analgesic use of Patients Submitted to Rotator Cuff Repair Surgery: A Prospective Cohort / Perfil nociceptivo e uso de analgésicos em pacientes submetidos à cirurgia de reparo do manguito rotador: Coorte prospectiva

Abstract Objective This study aimed to evaluate the nociceptive profile and the intake of analgesic drugs of patients submitted to rotator cuff repair surgery. Also, to evaluate the nociceptive thresholds and the integrity of the descending inhibitory system, pain catastrophism and prevalence of nociceptive or neuropathic pain. Methods Approved by the Ethics Committee of La Salle University (1.325.433/2015). 40 patients (>18 years old) who underwent rotator cuff repair surgery (divided in small and large injuries) were recruited. The used instruments were: Sociodemographic Questionnaire, Functional Pain Scale, Visual Analogue Scale (VAS), Quantitative Sensory Test (QST) and Conditioned Pain Modulation Task (CPM). Results Patients had a significant difference in pain thresholds QST heat (independent samples t test) and quality of sleep, mood and anxiety (paired t test) in groups preoperative. There was a significant correlation between preoperative CPM and postoperative VAS (Pearson Correlation). It was observed that, in preoperative, 38 patients used analgesics continuously. Besides that, in postoperative, use of opioid drugs was higher in patients with small injury (13 patients) than in those with large injury (9 patients). Conclusion Therefore, patients with rotator cuff injuries did not present alterations in the descending inhibitory system, but showed alterations in pain thresholds, which may interfere in the postoperative period and still be related to the consumption of analgesics.

Resumo Objetivo O objetivo deste estudo foi avaliar o perfil nociceptivo e o uso de analgésicos em pacientes submetidos à cirurgia de reparo do manguito rotador. Além disso, os limiares nociceptivos e a integridade do sistema inibidor descendente, o catastrofismo da dor e a prevalência de dor nociceptiva ou neuropática também foram analisados. Métodos Este estudo foi aprovado pelo Comitê de Ética da Universidade La Salle (1.325.433/2015). Quarenta pacientes (maiores de 18 anos) submetidos à cirurgia de reparo do manguito rotador (divididos entre aqueles com lesões pequenas e grandes) participaram do estudo. Os instrumentos utilizados foram o Questionário Sociodemográfico, a Escala Funcional de Dor, a Escala Visual Análoga (EVA), o Teste Sensorial Quantitativo (QST) e a Tarefa de Modulação Condicionada da Dor (CPM). Resultados Os pacientes apresentaram diferenças significativas nos limiares de dor e QST de calor (teste t de amostras independentes) e qualidade do sono, humor e ansiedade (teste t pareado) nos grupos pré-operatórios. Houve uma correlação significativa entre CPM pré-operatória e EVA pós-operatória (correlação de Pearson). Observou-se que, no período pré-operatório, 38 pacientes utilizavam analgésico de forma contínua. Além disso, no período pós-operatório, o uso de opioides foi maior nos pacientes com lesões pequenas (13 pacientes) em comparação àqueles com lesões grandes (nove pacientes). Conclusão Os pacientes com lesão do manguito rotador não apresentaram alterações no sistema inibidor descendente, mas sim alterações nos limiares de dor, o que pode interferir no período pós-operatório e estar relacionado ao consumo de analgésicos.

Estimación del dolor durante el perioperatorio: Una revisión narrativa de los dispositivos disponibles / Estimative pain measurement during perioperative period: a review of current available devices

Pain is a complex subjective organic function which is influenced by sensorial, emotional, cognitive and behavioral elements. Despite the wide offer of pain measurement devices in the perioperative period, none of them is completely validated for their transverse use in the anesthetic practice. The aim of this review is to present the existing devices for objective pain evaluation during the perioperative period along with the scientific evidence supporting each of them. Articles from the PubMed/MEDLINE literature search engine were reviewed. As result, 37 articles were selected due to its relevance, from which 13 pain assessment devices were described, regarding its clinical relevance as well as the amount of scientific evidence found. Among them are ANI, NOL, pupillometry, qNOX, and others. The nociceptive measurement performed by most of these is based mainly on the evaluation of the autonomic nervous system activity and variations of the electroencephalographic signal. However, it is not possible to recommend any particular device. This review aims to offer a broad overview of the available options in order to estimate the role that each of them could play in clinical anesthesiology practice.

El dolor es una experiencia subjetiva compleja en la que inciden elementos sensoriales, emocionales, cognitivos y conductua- les. A pesar de una amplia oferta de dispositivos para medir dolor en el perioperatorio, hoy no existe un instrumento de medición de analgesia validado y utilizado transversalmente en la práctica anestésica. El objetivo de esta revisión es presentar las actuales opciones disponibles para la medición del dolor agudo utilizadas en el período perioperatorio junto con la evidencia científica que respalda cada una de ellas. Se realizó una revisión de la literatura utilizando como fuente de búsqueda bibliográfica la base de datos MEDLINE/pubMed utilizando términos MESH. Como resultado, se seleccionaron 37 artículos de acuerdo a su importancia, a partir de los cuales se describen 13 dispositivos de valoración nociceptiva, a propósito de su relevancia clínica como también por la cantidad de evidencia científica encontrada. Entre ellos destacan ANI, NOL, pupilometría, qNOX, entre otros. La medición nociceptiva realizada por la mayoría de estos se basa principalmente en la evaluación de la actividad del sistema nervioso autónomo y variaciones de la señal electroencefalográfica. Sin embargo, no es posible recomendar algún dispositivo en particular. Esta revisión pretende ofrecer una visión amplia de las opciones disponibles con el fin de estimar el rol que cada uno de ellos podría desempeñar en la práctica clínica anestesiológica.

Mecanismos de modulación central del dolor: revisión de la literatura / Mechanisms of central pain modulation: literature review

RESUMEN: La percepción del dolor resulta de múltiples y dinámicos mecanismos en el sistema nervioso central (SNC) y periférico que inhiben o facilitan el estímulo y respuesta nociceptiva. Sin embargo, la principal capacidad de modulación esta a cargo del SNC. Los estímulos nociceptivos son detectados por terminaciones nerviosas libres de neuronas periféricas que sinaptan con neuronas aferentes secundarias de la médula espinal. Luego estas fibras decusan para formar las vías nociceptivas ascendentes. Una vez alcanzadas las estructuras subcorticales, se activan las neuronas del tálamo, quienes envían el estímulo hacia la corteza somatosensorial, desencadenando la percepción consciente del dolor y activando el sistema inhibitorio descendente. Para que la modulación nociceptiva se realice, es necesaria la participación de diversas sustancias o neurotransmisores que conectan áreas del SNC especializadas. Por lo tanto, el objetivo de este estudio fue realizar una revisión de la literatura respecto de los mecanismos que participan en los procesos de modulación central del dolor.

SUMMARY: Pain perception results from multiple and dynamic mechanisms in the central nervous system (CNS) and peripheral nervous system that inhibit or facilitate stimulation and nociceptive response. However, neuromodulation is mainly a function of the CNS. Nociceptive stimulus is detected by peripheral neurons receptors that synapse with the secondary afferent neurons of the spinal cord. These fibers cross to conform the ascending nociceptive pathways. Once the subcortical structures are reached, the thalamus`s neurons are activated; the thalamus send the stimulus to the somatosensory cortex, triggering the conscious perception of pain and activating the descending inhibitory system. For the nociceptive modulation to be carried out, the participation of various substances or neurotransmitters that connect specialized CNS areas is necessary. Therefore, the aim of this study was to review the literature regarding the mechanisms involved in central pain modulation processes.

Importancia semiológica del dolor durante etapas de un proceso inflamatorio pulpar / Semiological importance of pain during the stages of a pulpal inflammation process

RESUMEN Introducción: Existe la tentativa de realizar un diagnóstico del proceso inflamatorio pulpar, basado en el aspecto histopatológico, el cual es irreal pues no se puede comparar estos hallazgos con los clínicos. Resulta más objetivo y confiable, analizar las características del dolor que expresa la evolución pulpar en cada etapa y establecer un diagnóstico certero que permita precisar el tipo de tratamiento. Objetivo: Interpretar el curso de un proceso inflamatorio pulpar a través de las variables asociadas a estímulos nociceptivos. Métodos: Se realizó una revisión bibliográfica sobre las variables en relación con el dolor y su asociación con un estado inflamatorio pulpar. Se analizaron 24 artículos científicos en relación con el dolor pulpar, se escogieron 15 por ser los más afines al propósito perseguido, y todos corresponden a los últimos 5 años, publicados en revistas internacionales y nacionales. PubMed se utilizó como fuente fundamental de búsqueda; otras bases de datos también consultadas fueron Lilacs, Hinari y Medline. Análisis e integración de la información: Las condiciones pulpares se clasifican como: pulpitis reversible, transicional, irreversible y pulpa necrótica. La semiología del dolor se sustenta en cuatro variables básicas asociadas a los estímulos nociceptivos que son: cualidad del dolor pulpar puede ser punzante o continuo, su curso intermitente o continuo, su localización limitado a una región de la boca, irradiado y referido, y su intensidad considerada como leve, moderado o severo. Conclusiones: Las variables asociadas a los estímulos nociceptivos revisten importancia semiológica, pues permiten valorar las manifestaciones dolorosas por las que transita un proceso inflamatorio pulpar(AU)

ABSTRACT Introduction: Attempts have been made to diagnose the pulpal inflammatory process based on its histopathological features, but to no avail, for these findings cannot be compared with clinical results. It would be more objective and reliable to analyze the characteristics of the pain expressing the pulpal evolution at each stage and establish an accurate diagnosis allowing the choice of the type of treatment to be indicated. Objective: Interpret the course of a pulpal inflammatory process through variables associated to nociceptive stimuli. Methods: A bibliographic review was conducted about the study variables with respect to pain and its association to a pulpal inflammatory state. A total 24 scientific papers were analyzed which dealt with pulpal pain, of which 15 were selected for being the most closely related to the goal pursued and having been published in international and national journals in the last five years. PubMed was the main source searched, while other databases such as Lilacs, Hinari and Medline were also consulted. Data analysis and integration: Pulpal conditions are classified into reversible, transitional, irreversible pulpitis and necrotic pulp. Pain semiology is based on the following four basic variables associated to nociceptive stimuli: pulpal pain quality (sharp or continuous), course (intermittent or continuous), location (limited to a region in the mouth, radiating or referred) and intensity (mild, moderate or severe). Conclusions: The variables associated to nociceptive stimuli are semiologically important, for they make it possible to evaluate the painful manifestations gone through by a pulpal inflammatory process(AU)

Dolor psíquico: una mirada a su condición actual / Psychic pain: a look to its current condition

Resumen No obstante, el dolor ha permanecido ligado a la existencia humana y que la asistencia al dolor es una de las principales funciones de los equipos de salud, el dolor psíquico no ha estado presente en la formación médica ni en la investigación. En el presente estudio se plantearon dos preguntas: ¿Cuál es el estado actual de la investigación considerando las perspectivas psicológicas y neurobiológicas del dolor psicológico? y ¿qué lugar ocupa el dolor psicológico en la asistencia actual de los pacientes? Los objetivos fueron: 1) Revisar la significación del dolor en su perspectiva histórica y su relación con la existencia humana; 2) Examinar las bases neurobiológicas del dolor físico y psíquico; 3) Reflexionar acerca del lugar que le cabe al dolor psíquico en los programas de cuidados paliativos del dolor. Como metodología se revisó la literatura publicada en Medline, Scopus y Scielo tomando las palabras claves: Dolor Psíquico, Dolor Mental y Dolor Emocional. Se revisan las razones por las cuales el dolor psíquico ha permanecido postergado, considerando que la experiencia del dolor es una experiencia psíquica debido a que puede haber dolor psíquico sin dolor físico, pero no al revés. El dolor psíquico puede ser tan real como otras formas de dolor más aun considerando que puede ser tan severo como para exponer a una persona al riesgo suicida. Se analizan las estructuras involucradas en el dolor psíquico y físico y se comenta acerca del rol de los médicos en su deber de aliviar el dolor.

Although pain has been present trough human history and that its assistance is one of the most important activities of health teams, psychic pain hasn't been present properly neither in medical education nor research. In order to assess this topic the author has carried out a review following these two questions: What is the state of the art considering psychological and neurobiological perspectives of psychic pain? and which place is occupying psychic pain in the current assistance of patients? The proposed objectives were: 1) To evaluate historical aspects of pain and its place in human life; 2) To evaluate neurobiological basis of psychic and somatic pain and 3) To reflect about the place psychic pain has currently in Paliative Care Programs. The methodology was the review of current literature published in Medline, Scopus and Scielo considering the following key words: Psychological Pain, Mental Pain and Emotional Pain. Special consideration is given to how this topic has been postponed and the reasons for this situation, considering that the whole experience of pain is psychological, as there may be psychical pain without physical pain but not otherwise. Psychic pain is not less real than other kind of pain; it may be even more severe as to put a person at risk of suicide. Mention is made about the boundaries between physical and psychic pain considering that they are not clear, as they involve similar structures. The role of medical doctors in helping to alleviate pain of patients is addressed.

Korean Pain Descriptors in Patients with Neuromusculoskeletal Pain

OBJECTIVE: To evaluate which Korean pain descriptors are frequently used in the patients with neuromusculoskeletal diseases and compare the frequency of Korean pain descriptor according to age, gender, pain pattern and intensity, and clinical diagnosis.METHOD: Two hundreds sixty nine patients with neuromusculoskeletal diseases were enrolled in this study. The patients were asked to fill out a pain questionnaire using Korean. The Korean pain descriptors were collected and classified according to neurophysiological mechanism. The frequency of Korean pain descriptor was analyzed by age, gender, pain pattern and intensity, and clinical diagnosis. They were divided into axial spine and peripheral joint pain group depending on the location of causal disease and shoulder pain descriptors were divided into intra-articular and bursa group.RESULTS: Among 24 Korean pain descriptors, ‘arida’ was the most common pain descriptor, followed by ‘ssusida’ and ‘jjireunda’. When the pain descriptors were classified according to neurophysiological mechanism, superficial somatic pain was the most common, followed by deep somatic pain. There was a significant difference in the frequency of the pain descriptor between axial spine and peripheral joint pain group (p=0.007). The pain descriptor ‘danggida’ was used significantly more in the patients with axial spine pain than peripheral joint pain (p=0.024). However, there was no significant difference in other factors.CONCLUSION: The patients with neuromusculoskeletal diseases expressed their pain using various Korean pain descriptors with stabbing nature and superficial somatic pain. Our results may be helpful to assess and develop a new Korean pain quality measure in the patients with neuromusculoskeletal diseases.

Systematic review and analysis on the appropriate diseases in clinical treatment with 's subcutaneous needling therapy / 中国针灸

The clinical research articles relevant with 's subcutaneous needling therapy (FSN) were retrieved from CNKI, WANFANG, CBM and PubMed databases till January 2018 since the establishment of database. According to the general international criteria of disease classification, the diseases involved in the articles were classified and summarized. In terms of the clinical application and research of FSN, the questions were extracted and commented through expert's consultation. As a result, 412 articles were included. The statistical results of disease spectrum indicated that FSN was adopted in 65 kinds of diseases in 11 systems. Of these diseases, the relevant somatic pain disorders in the musculoskeletal system were the most appropriate. Professor explained that the clinical physicians of FSN should select the muscle-related disorders as the clinical research subject and treat them with normalized manipulation of FSN. The research on FSN is still at the preliminary stage. It needs more high-quality clinical and basic researches to provide the evidences for the therapeutic effects of FSN.

Antidepressants in Spine Surgery: A Systematic Review to Determine Benefits and Risks

Antidepressant drugs can be advantageous in treating psychiatric and non-psychiatric illnesses, including spinal disorders. However, spine surgeons remain unfamiliar with the advantages and disadvantages of the use of antidepressant drugs as a part of the medical management of diseases of the spine. Our review article describes a systematic method using the PubMed/Medline database with a specific set of keywords to identify such benefits and drawbacks based on 17 original relevant articles published between January 2000 and February 2018; this provides the community of spine surgeons with available cumulative evidence contained within two tables illustrating both observational (10 studies; three cross-sectional, three case-control, and four cohort studies) and interventional (seven randomized clinical trials) studies. While tricyclic antidepressants (e.g., amitriptyline) and duloxetine can be effective in the treatment of neuropathic pain caused by root compression, venlafaxine may be more appropriate for patients with spinal cord injury presenting with depression and/or nociceptive pain. Despite the potential associated consequences of a prolonged hospital stay, higher cost, and controversial reports regarding the lowering of bone mineral density in the elderly, antidepressants may improve patient satisfaction and quality of life following surgery, and reduce postoperative pain and risk of delirium. The preoperative treatment of preexisting psychiatric diseases, such as anxiety and depression, can improve outcomes for patients with spinal cord injury-related disabilities; however, a preoperative platelet function assay is advocated prior to major spine surgical procedures to protect against significant intraoperative blood loss, as serotonergic antidepressants (e.g., selective serotonin reuptake inhibitors) and bupropion can increase the likelihood of bleeding intraoperatively due to drug-induced platelet dysfunction. This comprehensive review of this evolving topic can assist spine surgeons in better understanding the benefits and risks of antidepressant drugs to optimize outcomes and avoid potential hazards in a spine surgical setting.

Analysis of Neuropathic Pain Using Magnetic Resonance Imaging T2 Mapping of Intervertebral Disc in Chronic Low Back Pain

STUDY DESIGN: Cross sectional study. PURPOSE: The study aimed to analyze mechanisms underlying chronic low back pain (CLBP) using magnetic resonance imaging (MRI) T2 mapping of the intervertebral disc (IVD). OVERVIEW OF LITERATURE: MRI T2 mapping utilizes the T2 values for quantifying moisture content and collagen sequence breakdown. We previously used MRI T2 mapping for quantifying the extent of IVD degeneration (IVDD) and showed a correlation between the degeneration of the posterior annulus fibrosus (AF) and CLBP. METHODS: We enrolled 40 patients with CLBP (17 males, 23 females; mean age, 50.8±1.6 years; range, 22–60 years). IVDs were categorized as the anterior AF, nucleus pulposus (NP), and posterior AF, and T2 value for each disc was measured. T2 values, assessed using the Japanese neuropathic pain (NeP) screening questionnaire, of the NeP and nociceptive pain (NocP) groups were compared. RESULTS: T2 values of the NocP and NeP groups were 64.7±5.6 ms and 58.1±2.3 ms for the anterior AF; 67.0±4.6 ms and 59.6±2.1 ms for NP; and 70.7±4.6 ms and 51.0±1.2 ms for the posterior AF, respectively. T2 values for IVDD were significantly lower in the NeP group than those in the NocP group (p<0.01). CONCLUSIONS: The results indicate a correlation between the degeneration of posterior AF and NeP. MRI T2 mapping may be beneficial for detecting NeP caused by IVDD and can help formulate targeted analgesic therapies.

Analgesic effects of eucalyptus essential oil in mice / 대한통증학회지

BACKGROUND: The use of aroma oils dates back to at least 3000 B.C., where it was applied to mummify corpses and treat the wounds of soldiers. Since the 1920s, the term “aromatherapy” has been used for fragrance therapy with essential oils. The purpose of this study was to determine whether the essential oil of Eucalyptus (EOE) affects pain pathways in various pain conditions and motor coordination. METHODS: Mice were subjected to inhalation or intraperitoneal injection of EOE, and its analgesic effects were assessed by conducting formalin, thermal plantar, and acetic acid tests; the effects of EOE on motor coordination were evaluated using a rotarod test. To determine the analgesic mechanism, 5′-guanidinonaltrindole (κ-opioid antagonist, 0.3 mg/kg), naltrindole (δ-opioid antagonist, 5 mg/kg), glibenclamide (δ-opioid antagonist, 2 mg/kg), and naloxone (μ-opioid antagonist, 4, 8, 12 mg/kg) were injected intraperitoneally. RESULTS: EOE showed an analgesic effect against visceral pain caused by acetic acid (EOE, 45 mg/kg); however, no analgesic effect was observed against thermal nociceptive pain. Moreover, it was demonstrated that EOE did not have an effect on motor coordination. In addition, an anti-inflammatory effect was observed during the formalin test. CONCLUSIONS: EOE, which is associated with the μ-opioid pain pathway, showed potential effects against somatic, inflammatory, and visceral pain and could be a potential therapeutic agent for pain.

Effect of sec-O-glucosylhamaudol on mechanical allodynia in a rat model of postoperative pain / 대한통증학회지

BACKGROUND: This study was performed in order to examine the effect of intrathecal sec-O-glucosylhamaudol (SOG), an extract from the root of the Peucedanum japonicum Thunb., on incisional pain in a rat model. METHODS: The intrathecal catheter was inserted in male Sprague-Dawley rats (n = 55). The postoperative pain model was made and paw withdrawal thresholds (PWTs) were evaluated. Rats were randomly treated with a vehicle (70% dimethyl sulfoxide) and SOG (10 μg, 30 μg, 100 μg, and 300 μg) intrathecally, and PWT was observed for four hours. Dose-responsiveness and ED50 values were calculated. Naloxone was administered 10 min prior to treatment of SOG 300 μg in order to assess the involvement of SOG with an opioid receptor. The protein levels of the δ-opioid receptor, κ-opioid receptor, and μ-opioid receptor (MOR) were analyzed by Western blotting of the spinal cord. RESULTS: Intrathecal SOG significantly increased PWT in a dose-dependent manner. Maximum effects were achieved at a dose of 300 μg at 60 min after SOG administration, and the maximal possible effect was 85.35% at that time. The medial effective dose of intrathecal SOG was 191.3 μg (95% confidence interval, 102.3–357.8). The antinociceptive effects of SOG (300 μg) were significantly reverted until 60 min by naloxone. The protein levels of MOR were decreased by administration of SOG. CONCLUSIONS: Intrathecal SOG showed a significant antinociceptive effect on the postoperative pain model and reverted by naloxone. The expression of MOR were changed by SOG. The effects of SOG seem to involve the MOR.

Comparison of oxycodone and fentanyl for postoperative patient-controlled analgesia after orthopedic surgery

BACKGROUND: Oxycodone is widely used as bolus or patient-controlled analgesia (PCA) for control of postoperative pain. The aim of this study was to assess the efficacy and side effects of oxycodone for somatic pain by comparing oxycodone and fentanyl intravenous PCA after orthopedic surgery. METHODS: Seventy-three patients undergoing orthopedic surgery were randomly assigned to receive fentanyl or oxycodone using intravenous PCA (potency ratio 1:60). Pain severity at rest and with movement and adverse effects were assessed at 1, 6, 24, and 48 hours after surgery. The PCA dose and patient satisfaction scores were measured at 48 hours after surgery. RESULTS: The resting visual analogue scale (VAS) and moving VAS scores of the oxycodone group were significantly higher than those of the fentanyl group at 6 hours (P = 0.001, P = 0.021), but at 48 hours, the resting and moving VAS of the oxycodone group were significantly lower than those of the fentanyl group (P = 0.014, P = 0.037). There were no significant differences in adverse effects, satisfaction scores, dose of patient-controlled mode, or total cumulative PCA dose. CONCLUSIONS: With a 1:60 ratio of oxycodone to fentanyl when using PCA for pain control after orthopedic surgery, the use of larger doses of oxycodone for 6 hours is effective in controlling early postoperative pain.

The Availability of Quantitative Assessment of Pain Perception in Patients With Diabetic Polyneuropathy

OBJECTIVE: To evaluate the usefulness of the quantitative assessment of pain perception (QAPP) in diabetic polyneuropathy (DPN) patients. METHODS: Thirty-two subjects with DPN were enrolled in this study. The subjects’ pain perception was assessed quantitatively. Current perception threshold (CPT) and pain equivalent current (PEC) were recorded. All patients were tested with a nerve conduction study (NCS) for evaluation of DPN and pain-related evoked potential (PREP) for evaluation of small fiber neuropathy (SFN) on bilateral upper and lower limbs. All patients were asked to participate in tests such as visual analogue scale (VAS) and SF-36 Health Survey Version 2 to evaluate their subjective pain and quality of life, respectively. RESULTS: The PEC of QAPP showed significant correlations with VAS (p=0.002) and physical function surveyed with SF-36 Health Survey Version 2 (p=0.035). The results of QAPP had no correlation with NCS, but there was a significant relationship between the CPT of QAPP and PREP (p=0.003). CONCLUSION: The QAPP may be useful not only in providing objective evaluations of subjective pain in patients with DPN but also in the assessment of diabetic SFN.

Risk Factors of Neuropathic Pain after Total Hip Arthroplasty / 대한고관절학회지

PURPOSE: Pain caused by osteoarthritis is primarily nociceptive pain; however, it is considered that a component of this pain is due to neuropathic pain (NP). We investigated the effects of total hip arthroplasty (THA) in patients with NP diagnosed by the PainDETECT questionnaire. MATERIALS AND METHODS: One hundred sixty-three hips (161 patients) were evaluated. All patients were asked to complete the PainDETECT questionnaire based on their experience with NP, and clinical scores were evaluated using the Japanese Orthopaedic Association (JOA) Hip Score before and after THA. RESULTS: The patients of 24.5% reported NP before THA; 5.5% reported NP 2 months after THA. Prior to THA, there was no significant correlation between the PainDETECT score and the radiographic severity; however, there was a significant correlation between the PainDETECT score and JOA score. NP at 2 months after THA was not significantly correlated with pain scores at 1 week after THA; however, a significant correlation was observed between the preoperative pain score and NP at 2 months after THA. CONCLUSION: THA was useful for relieving nociceptive pain and for relieving NP in patients with hip osteoarthritis. Preoperative pain was a risk factor for NP after THA. Controlling preoperative pain may be effective for reducing postoperative NP.

Neuropathic cancer pain: prevalence, pathophysiology, and management

Neuropathic cancer pain (NCP) is caused by nerve damage attributable to the cancer per se, and/or treatments including chemotherapy, radiotherapy, and surgery; the prevalence is reported to be as high as 40%. The etiologies of NCP include direct nerve invasion or nerve compression by the cancer, neural toxicity, chemotherapy, and radiotherapy. NCP is subdivided into plexopathy, radiculopathy, and peripheral neuropathies, among several other categories. The clinical characteristics of NCP differ from those of nociceptive pain in terms of both the hypersensitivity symptoms (burning, tingling, and an electrical sensation) and the hyposensitivity symptoms (numbness and muscle weakness). Recovery requires several months to years, even after recovery from injury. Management is complex; NCP does not usually respond to opioids, although treatments may feature both opioids and adjuvant drugs including antidepressants, anticonvulsants, and anti-arrhythmic agents, all of which improve the quality-of-life. This review addresses the pathophysiology, clinical characteristics and management of NCP, and factors rendering pain control difficult.

Peripheral Leptin Signaling Mediates Formalin-Induced Nociception / 神经科学通报·英文版

Accumulating evidence suggests that obesity is associated with chronic pain. However, whether obesity is associated with acute inflammatory pain is unknown. Using a well-established obese mouse model induced by a high-fat diet, we found that: (1) the acute thermal pain sensory threshold did not change in obese mice; (2) the model obese mice had fewer nociceptive responses in formalin-induced inflammatory pain tests; restoring the obese mice to a chow diet for three weeks partly recovered their pain sensation; (3) leptin injection induced significant phosphorylation of STAT3 in control mice but not in obese mice, indicating the dysmodulation of topical leptin-leptin receptor signaling in these mice; and (4) leptin-leptin receptor signaling-deficient mice (ob/ob and db/db) or leptin-leptin receptor pathway blockade with a leptin receptor antagonist and the JAK2 inhibitor AG 490 in wild-type mice reduced their nociceptive responses in formalin tests. These results indicate that leptin plays a role in nociception induced by acute inflammation and that interference in the leptin-leptin receptor pathway could be a peripheral target against acute inflammatory pain.

Preliminary molecular characterization of a proinflammatory and nociceptive molecule from the Echinometra lucunter spines extracts

Background Sea urchins are animals commonly found on the Brazilian shoreline, being Echinometra lucunter the most abundant species. Accidents caused by E. lucunter have been reported as one of the most frequent in Brazil, and are characterized by intense pain and inflammation, consequence of spine puncture in the skin. In order to characterize such toxic effects, we isolated one molecule that caused inflammatory and nociceptive effects. Methods E. lucunter specimens were collected without gender distinction. Spines were removed and molecules were extracted, fractionated by RP-HPLC and assayed for inflammatory and nociceptive activity, in a biological-driven fractionation way, until the obtainment of one active molecule and its subsequent analysis by mass spectrometry (MS and MS/MS). For inflammation, intravital microscopy was performed on the mouse cremaster muscle, in order to evaluate rolled, adherent and migrating leukocytes. Paw edema was also evaluated. For the nociceptive activity, the paw pressure test was performed in rats. Results One molecule could be isolated and related to the inflammatory and nociceptive activity. Regarding inflammation, increase in adherent and migrating cells was observed in the cremaster muscle after the administration of the molecule. Corroborating the inflammatory response, paw edema was also observed, although only in 20% of controls and 20 min after injection. Additionally, this molecule was able to decrease significantly the pain threshold, characterizing hyperalgesia. This molecule was analyzed by mass spectrometry, and according to the exact molecular mass, isotopic distribution and fragmentation profile, it was possible to propose the molecular formula C29H48N3O10. Conclusions One isolated molecule from the spine extract of E. lucunter is able to elicit inflammation and hypernociception in animal models, which is in agreement with the effects observed in sea urchin accidents.(AU)

Hindi version of short form of douleur neuropathique 4 (S-DN4) questionnaire for assessment of neuropathic pain component: a cross-cultural validation study

BACKGROUND: Pain with neuropathic characteristics is generally more severe and associated with a lower quality of life compared to nociceptive pain (NcP). Short form of the Douleur Neuropathique en 4 Questions (S-DN4) is one of the most used and reliable screening questionnaires and is reported to have good diagnostic properties. This study was aimed to cross-culturally validate the Hindi version of the S-DN4 in patients with various chronic pain conditions. METHODS: The S-DN4 is already translated into the Hindi language by Mapi Research Trust. This study assessed the psychometric properties of the Hindi version of the S-DN4 including internal consistency and test-retest reliability after 3 days' post-baseline assessment. Diagnostic performance was also assessed. RESULTS: One hundred sixty patients with chronic pain, 80 each in the neuropathic pain (NeP) present and NeP absent groups, were recruited. Patients with NeP present reported significantly higher S-DN4 scores in comparison to patients in the NeP absent group (mean (SD), 4.7 (1.7) vs. 1.8 (1.6), P < 0.01). The S-DN4 was found to have an AUC of 0.88 with adequate internal consistency (Cronbach's α = 0.80) and a test-retest reliability (ICC = 0.92) with an optimal cut-off value of 3 (Youden's index = 0.66, sensitivity and specificity of 88.7% and 77.5%). The diagnostic concordance rate between clinician diagnosis and the S-DN4 questionnaire was 83.1% (kappa = 0.66). CONCLUSIONS: Overall, the Hindi version of the S-DN4 has good internal consistency and test-retest reliability along with good diagnostic accuracy.