Neuropathic pain (NeP) is generally characterized by the combination of positive and negative phenomena (ie, pain, paresthesia and/or dysesthesia, and sensory deficits) with a plausible neurological distribution [8,35,36,38,44]. The lack of operational and validated diagnostic criteria remains a difficulty in this field, probably accounting for the poor recognition of NeP and the undertreated or inappropriate treatment of this condition. The development and validation of clinical tools in the form of questionnaires has undoubtedly been one of the most active and productive aspects of clinical research on NeP in the last decade. These clinical instruments, which may be used in both daily practice and clinical research, can be used for identifying (screening) or measuring NeP through a limited number of items, mostly related to description of the various qualities of the pain (ie, pain descriptors). The great success and rapid spread of these questionnaires – probably due to their simplicity and ease of use – highlights a previously unmet need in this field. In the research setting, these questionnaires have not only improved characterization, but they have also led to the development of a new conceptualization of NeP syndromes as multidimensional entities. This change in the way in which NeP syndromes are viewed may have major implications in the design of future drug trials and, more generally, the management of these syndromes. However, like any tool, these questionnaires also have limitations. In particular, screening NeP and measuring neuropathic symptoms are different processes. Screening may serve to identify patients with NeP, particularly by nonspecialists, while measuring NeP symptoms is helpful to evaluate treatment effects and discriminate between various pain mechanisms associated with distinct dimensions of neuropathic pain experience. Thus, the use of these questionnaires should be governed by their specific clinical applications and the patient populations defined in the corresponding validation study, and the results obtained should always be interpreted in the context of a more global clinical assessment of the patient’s pain and quality of life.

Diagnosis and assessment of neuropathic pain: the saga of clinical tools.

Section 2: Pain ManagementParavertebral Blocks

The Pain Research Group of the world health organization (WHO) Collaborating Centre for Symptom Evaluation in Cancer Care had developed the Brief Pain Inventory (BPI), a pain assessment tool for use with cancer patients. The BPI measures both the intensity of pain (sensory dimension) and interference of pain in the patient's life (reactive dimension). The objective of this review paper was to provide a detailed update of existing evidence on applicability of BPI in evaluation of patients with cancer pain. The BPI demonstrated good construct and concurrent validity. It was translated and validated into many languages - Brazilian, Chinese, Greek, Hindi, Italian, Japanese, Korean, Malay, Norwegian, Polish, Russian, Spanish, Taiwanese and Thai. The BPI was validated in patient populations such as bone metastases, breast cancer and postoperative cancer patients. The BPI can be used both as a quantitative or a qualitative measure for statistical analysis. The BPI was a powerful tool and, having demonstrated both reliability and validity across cultures and languages, was being adopted in many countries for clinical pain assessment, epidemiological studies, and in studies on the effectiveness of pain treatment. Future studies are warranted on its responsiveness and cross-cultural adaptation into other cancer pain syndromes and into other Indian languages.

Utilization of brief pain inventory as an assessment tool for pain in patients with cancer: A focused review

https://www.jpsmjournal.com/article/S0885-3924(12)00212-6/pdf

Prevalence, characteristics, and factors associated with chronic pain with and without neuropathic characteristics in São Luís, Brazil.

Background

Topical therapy may provide additional benefit in patients with painful diabetic neuropathy (PDN). This study was conducted to study the safety and efficacy of 0.025% capsaicin gel in this condition.



Methods

A 20-week, double-blind, crossover, randomized, single-center study enrolled subjects with PDN. They received 0.025% capsaicin gel or placebo for 8 weeks, with a washout period of 4 weeks between the two treatments. Primary efficacy end point was percent change in visual analog scale (0–100 mm) of pain severity. Secondary outcomes were score change in Neuropathic Pain Scale (NPS), short-form McGill Pain Questionnaires (SF-MPQ), proportion of patients who had pain score reductions of 30% and 50%, and adverse event.



Results

Of the 35 subjects screened, 33 were enrolled and 33 completed at least an 8-week treatment period. Intention-to-treat analysis showed no significant improvement in pain with capsaicin gel, compared with placebo with visual analog scale (VAS) score 28.8 mm vs. 34.6 mm (P = 0.53). No significant difference between the groups was found in SF-MPQ (7.4 vs. 7.71, P = 0.95), NPS (29.4 vs. 31.3, P = 0.81), and proportion of patients who had 30% or 50% pain relief. Capsaicin gel was well tolerated with minor skin reaction.



Conclusions

0.025% capsaicin gel is safe and well tolerated, but does not provide significant pain relief in patients with PDN.

0.025% capsaicin gel for the treatment of painful diabetic neuropathy: a randomized, double-blind, crossover, placebo-controlled trial.

Objective: To cross-culturally adapt the neuropathic pain diagnostic questionnaire (DN4) to Thai language Material and Method: Phase 1: Forward and backward translation followed by assessment of semantic equivalence. Phase 2: Testing of the questionnaire in 30 neuropathic pain patients who were seen and diagnosed by experts, followed by modifications to produce a final version. Results: All the Thai translated pain descriptors except ‘tingling’ got high percentages of understanding among neuropathic pain patients in the first round of testing. After some adaptation of the Thai word for ‘tingling’ had been made, the new translated word was retested, and all subjects doing the retest understood the word very well. Conclusion: The Thai DN4 questionnaire was systematically translated and validated. This offers a simple Thai neuropathic pain diagnostic tool for clinical use. Keywords: Thai language, Neuropathic pain, Diagnostic questionnaire

https://www.si.mahidol.ac.th/th/publication/2007/Vol90_No.9_1860_6010.pdf

Cross-cultural adaptation to the Thai language of the neuropathic pain diagnostic questionnaire (DN4).

Approximately 80% of the world's population lives in countries with little or no access to pain management. These countries also have 74% of the world's deaths from cancer and human immunodeficiency virus. Appropriate use of oral opioids can control 80%-90% of cancer pain. However, only 6.7% of the world's medical opioids are available in these low-resource countries. With the Lancet Commission on Global Surgery calling for a significant expansion of surgical services, postoperative pain management will need to be an increasing focus of our attention. There are multiple barriers to providing effective pain management. These include the type and funding of the health care system, the size and educational level of the workforce, the ease of access to effective medications, and the expectations and knowledge base of the community. Some barriers can be addressed by education at the undergraduate level, postgraduate level, and community level. Others will require continued advocacy at government level. Only when we tackle these problems will the considerable neglect of access to effective pain treatment in low- and middle-income countries be lessened.

Pain: A Neglected Problem in the Low-Resource Setting.

Background Pain is one of the most frequent and deleterious symptoms for patients with advanced cancer. Pain assessment is important because it is used for detecting severity of disease and the response to treatment. To provide the adequate treatment for pain relief in cancer patients, an assessment tool should be used for pain evaluation. Moreover, suitable tools for pain evaluation should be validated in local language to obtain better pain information. Objective The objective of the present study was to demonstrate validity and reliability of the Thai version of the Brief Pain Inventory (BPI-T), which is a simple and concise instrument for pain assessment. Material and method The available data were obtained from 520 patients with cancer pain. The data included pain severity, which patients reported using Thai version of Brief Pain Inventory (BPI-T). The pain severity and pain information were reported three times with 2-week intervals between each assessment time point. Results Factor analysis of the Thai version of the Brief Pain Inventory resulted in two factors, pain severity and pain interference, showing valid structures consistent with other language versions of the instrument. Cronbach's alphas, computed for pain interference and pain severity item were 0.88 and 0.89, 0.01 and 0.92, and 0.93 and 0.94, for first, second, and third assessment time, respectively. Conclusion Thai version of the Brief Pain Inventory is a reliable and valid instrument for cancer pain assessment in Thailand

https://www.si.mahidol.ac.th/th/publication/2009/Vol92_No.1_34_8504.pdf

Validation of the Thai Version of Brief Pain Inventory (BPI-T) in cancer patients.

Background The supply of controlled drugs is limited in the Far East, despite the prevalence of health disorders that warrant their prescription. Reasons for this include strict regulatory frameworks, limited financial resources, lack of appropriate training amongst the medical profession and fear of addiction in both general practitioners and the wider population. Consequently, the weak opioid tramadol has become the analgesic most frequently used in the region to treat moderate to severe pain. Methods To obtain a clearer picture of the current role and clinical use of tramadol in Southeast Asia, pain specialists from 7 countries in the region were invited to participate in a survey, using a questionnaire to gather information about their individual use and experience of this analgesic. Results Fifteen completed questionnaires were returned and the responses analyzed. Tramadol is used to manage acute and chronic pain caused by a wide range of conditions. Almost all the specialists treat moderate cancer pain with tramadol, and every one considers it to be significant or highly significant in the treatment of moderate to severe non-cancer pain. The reasons for choosing tramadol include efficacy, safety and tolerability, ready availability, reasonable cost, multiple formulations and patient compliance. Its safety profile makes tramadol particularly appropriate for use in elderly patients, outpatients, and for long-term treatment. The respondents strongly agreed that tighter regulation of tramadol would reduce its medical availability and adversely affect the quality of pain management. In some countries, there would no longer be any appropriate medication for cancer pain or the long-term treatment of chronic pain. Conclusions In Southeast Asia, tramadol plays an important part in the pharmacological management of moderate to severe pain, and may be the only available treatment option. If it were to become a controlled substance, the standard of pain management in the region would decline.

/pdf/tramadol-a-valuable-treatment-for-pain-in-southeast-asian-4kni0jc3uy.pdf

Tramadol: a valuable treatment for pain in Southeast Asian countries

Objective To examine the profile and treatment pattern of patients with neuropathic pain attending Siriraj Pain Clinic Material and method A 2-year retrospective study of the prevalence of neuropathic pain, characteristics of the patients and the use of medical treatment Records of all the patients that attended Siriraj Pain Clinic from September 1, 2002 until September 30, 2004 were reviewed Results One thousand three hundred and thirty patients' records were reviewed Five hundred and three patients were diagnosed as having neuropathic pain The prevalence of neuropathic pain at Siriraj Pain Clinic during the survey period was 378% The average age of neuropathic pain patients was 54 years The most common type of neuropathic pain was peripheral type, nerve compression in particular The most common concomitant illness was malignant tumor The majority of patients (718%) had one pain location and the most common site was the lower extremity The main descriptions of neuropathic pain were radiating, electric shock-like, burning, numbing and shooting Oral medication was the most common method (79%) of pain-relief treatment Almost all of the patients (93%) had received more than one type of oral medication The most commonly used medicine was TCA (771%), followed by gabapentin (35%), carbamazepine (34%) and tramadol (243%) Most of the pain-relief medicines prescribed at this clinic were under the recommended doses for the treatment of neuropathic pain Conclusion Characteristics and treatment patterns of neuropathic pain at Siriraj Pain Clinic are similar to those seen in other pain clinics elsewhere in the world The high prevalence of neuropathic pain in the clinic indicates that this type of pain syndrome is increasingly critical to our clinical practice More educational programs on neuropathic pain and management are needed for Thai healthcare professionals

https://www.si.mahidol.ac.th/th/publication/2006/Vol89_No3_354.pdf

Pongparadee Chaudakshetrin

Papers

Cross-cultural adaptation to the Thai language of the neuropathic pain diagnostic questionnaire (DN4).

Pain: A Neglected Problem in the Low-Resource Setting.

Validation of the Thai Version of Brief Pain Inventory (BPI-T) in cancer patients.

Tramadol: a valuable treatment for pain in Southeast Asian countries

A survey of patients with neuropathic pain at Siriraj Pain Clinic