European Journal of Pain

German departments of anaesthesia were surveyed to determine current practice of postoperative pain management in children. The response rate of the survey was 58.6%: Questionnaires of 383 departments in which paediatric surgery was performed could be analyzed. 37.3% operated an acute pain service (APS). In 58.8% of the hospitals, postoperative pain management in children was mainly performed by surgeons or pediatricians. Anaesthesiologists or an APS were in charge for pain management in children in 38.6% of the institutions. Non‐opioid analgesics were the drugs most widely used (93.4%), whereas i.v. opioids were never used in 20.9% of the hospitals and used less than once a week in 28.7%. The intramuscular route was chosen at least occasionally by 27.7% of the respondents. Peripheral and central regional techniques were performed in most of the departments, however, frequency of use varied considerably between hospitals running or not running an APS. The majority performed the techniques of regional anaesthesia less than once a week. The basic primary quality criterion of pain therapy, a regular measurement and documentation of pain scores, was performed in only 4% of the institutions.

Paediatric pain management does not meet quality criteria and standards of care already established in adults. In the future, additional education of the medical staff considering analgesic techniques and measurement of pain scores has to be emphasized.

Since the isolation of morphine from opium by Serturner in 1806, morphine, which Osler referred to! as ‘God's own medicine’, has remained the analgesic of choice for the treatment of severe pain despite its known addictive potential and the attempts to replace it with synthetic or semi‐synthetic medications. Its early use was based on clinical experience alone until the identification of the opioid receptors and endogenous opioids 25 years ago. Advances in pharmacology and pharmacokinetics and the development of precision equipment to quantify the parent drugs and their metabolites in plasma have provided a better understanding of the mechanisms of action as well as adverse effects. Clinicians can now select the drug and route of administration to suit the patient's needs. The objective of care now is for clinical observation to be reinforced by randomized controlled trials and evidence‐based medicine, but controlled clinical trials are lacking for the use of opioids in chronic pain.

The cingulate cortex plays a key role in the affective component related to pain perception. This structure receives cholinergic projections and also plays a role in memory processing. Therefore, we propose that the cholinergic system in the anterior cingulate cortex is involved in the nociceptive memory process. We used scopolamine ( in ) microinjected into the anterior cingulate cortex, either before thermonociception followed by a sciatic denervation, between thermonociception and denervation or after both procedures (n=10 each). The vehicle group (saline solution 0.9%, n=14) was microinjected before thermonociception. Chronic nociception was measured by the autotomy score, which onset and incidence were also determined. Group scopolamine—thermonociception–denervation (STD) presented the lowest autotomy score as compared to vehicle and group thermonociception—denervation–scopolamine (TDS) (vehicle vs. STD, p=0.002, STD vs. TDS, p=0.001). Group thermonociception‐scopolamine‐denervation (TSD) showed a diminished autotomy score when compared to TDS (p=0.053). STD group showed a delay in the onset of AB as compared to the rest of the groups. Group TSD presented a significative delay (p=0.048) in AB onset when compared to group TDS. There were no differences in the incidence between groups. The results show that nociception‐related memory processed in the anterior cingulate cortex is susceptible of being modified by the cholinergic transmission blockade. When scopolamine is microinjected prior to the nociceptive stimuli, nociception‐related memory acquisition is prevented. The evidence obtained in this study shows the role of the anterior cingulate cortex in the acquisition of nociception‐related memory.

Đột quỵ là một căn bệnh phổ biến thường yêu cầu quá trình phục hồi chức năng, mà có thể bị kéo dài do đau vai. Tỷ lệ thực sự của đau vai sau đột quỵ vẫn chưa được đánh giá một cách đầy đủ. Để xác lập điều này, chúng tôi đã thực hiện một nghiên cứu tiềm năng trên 123 bệnh nhân liên tiếp được chẩn đoán mắc đột quỵ cấp trong thời gian 6 tháng. Bệnh nhân được đánh giá qua phỏng vấn, kiểm tra toàn diện về thấp khớp và thần kinh, sau 14 ngày kể từ khi bị đột quỵ, để tìm lịch sử đau vai theo các tiêu chí đã được xác định trước. Ngoài ra, chỉ số Barthel, điểm số HAD và các thang điểm đau cũng được ghi lại. Hai mươi lăm phần trăm bệnh nhân đã phát triển đau vai trong vòng 2 tuần sau khi bị đột quỵ. Có một mối liên hệ có ý nghĩa thống kê với suy giảm cảm giác bên cùng bên (p<0.005), kiểm tra thấp khớp bất thường (p<0.001) và điểm số trầm cảm (p<0.005).

Chúng tôi kết luận rằng đau vai sau đột quỵ phổ biến hơn những gì đã được nhận thức trước đây và ngoài việc kiểm tra khớp vai bất thường, điều này có thể còn liên quan đến suy giảm cảm giác ở chi trên. Cần phải thực hiện một cuộc kiểm tra thần kinh toàn diện để phát hiện sự mất cảm giác và do đó xác định bệnh nhân có nguy cơ. Điều này có lẽ được thực hiện tốt nhất thông qua một biểu mẫu có cấu trúc.

Synthetic heat is a perception of strong, but not painful, heat arising when skin is stimulated by an alternating pattern of adjacent cold and warmth. This study examines the contribution of different classes of nerve fibres to this perception. In 40 subjects changes in synthetic heat and thermal perceptions were studied during a 30‐min ischaemic nerve block in one reaction time, and one threshold determination task. Synthetic heat stimuli were described as hot or warm, but not as painful, and were preceded by a transient cold. Reaction times for synthetic heat stimuli did not differ from those for cold stimuli. Thresholds for synthetic heat and thermal stimuli were similar. During A fibre nerve block the perception of synthetic heat lost the cold component whereas the frequency of hot and warm descriptors did not change. The perception of cold stimuli changed, such that pure cold was replaced by dysaesthetic descriptors. Reaction times and thresholds for thermal and synthetic heat stimuli increased equally during the nerve block. It is concluded that the perception of synthetic heat most likely arises from the fusion of signals dependent on unmyelinated low threshold cold and warm receptors. It is not dependent on A‐δ cold fibres, and a contribution of nociceptors is quite unlikely. The possibility of a psychological contribution at the perceptual level is discussed.

Epidural opioids have been reported to provide superior analgesia in acute pain management. Despite the fact that the required doses are low, major side effects such as respiratory depression may still occur. In an effort to maximize analgesia and to minimize the rate of side effects, epidural NMDA receptor antagonists, especially ketamine, may be co‐administered with opioids. This study investigated whether ketamine had beneficial effects on fentanyl‐ or morphine‐induced antinociception in an acute pain model in rats.

In male Wistar rats, an epidural catheter was placed under general anaesthesia. After 1 week the animals were subjected to the tail withdrawal reaction (TWR) test. After determination of the basal reaction latencies, fentanyl, morphine, ketamine or combinations of an opioid with ketamine were administered epidurally. TWR latencies were measured for up to 2 h after treatment.

Both opioids showed a dose related antinociceptive effect. Fentanyl had a fast onset and a short duration of action whereas the reverse was true for morphine. Ketamine exhibited only limited antinociceptive properties. In the combinations, ketamine improved morphine‐induced antinociception both in terms of maximal possible effect (MPE) as well as in duration of action. The combination of fentanyl with ketamine did not result in any improvement, neither in terms of MPE nor in duration of action. Moreover, increasing doses of ketamine tended to decrease the MPE of various doses of fentanyl. These data confirm that ketamine, contrary to opioids, does not possess important antinociceptive properties in an acute test such as the TWR test. Furthermore, these data indicate that additive drugs such as ketamine may have different effects on different opioids.

The objective of this paper is to test and correct for systematic differences in reporting of pain severity among older adults by age, gender, ethnic group and socio‐economic status using anchoring vignettes. Data from a national survey of community‐dwelling older Singaporeans (aged 60 years and over) conducted in 2009 was used. Respondents were asked to rate the severity of their own pain as well as that of others described in the vignettes on a five‐point scale ranging from none to extreme. An ordered probit model was used to estimate the coefficients of the independent variables (age, gender, ethnic group, education, housing type) on self‐reported pain. Reporting heterogeneity in pain severity was then corrected using a Hierarchical Ordered Probit model. The results showed that before correcting for reporting heterogeneity, women, those older, and those of Malay ethnicity reported greater severity of pain, while there was no association of reported pain severity with housing type and education. However, after correcting for reporting heterogeneity, while women and those older were found to have an even greater severity of pain than what they had reported, Malays were found to have a lower severity of pain than what they had reported. We conclude that there are systematic differences in reporting pain severity by age, gender and ethnic group. We propose that pain management may be improved if medical professionals take into account reporting heterogeneity for pain severity among various population sub‐groups in Singapore.

Background and aims: Afferent large fibre impairment has been reported as a useful predictor of postherpetic neuralgia (PHN) in patients with acute herpes zoster infection, using an electromechanical device to provide quantitative vibrametry. We aimed to demonstrate a clinically significant increase in vibration threshold in individuals with PHN compared to age‐matched controls, using the portable and affordable Rydel—Seiffer graduated tuning fork.

Methods: We studied 45 PHN subjects aged over 55 years, and 45 age‐matched controls with no history of herpes zoster infection. We excluded subjects with a history of disorders associated with neuropathy or immunocompromise. Measurements were performed at the ulnar styloid process and the head of the first metatarsal on the right side, in a warm room with the subject seated. Readings were taken in triplicate and the data analysed by a repeated measures design.

Results: We observed a significant difference in vibration threshold at both wrist and toe between the PHN and control groups (p<0.001). Age‐stratification of subjects produced an increased and clinically useful difference between the two groups at both sites in subjects between 55 and 70 years (p<0.0001).

Conclusions: We have shown a statistically significant decrease in vibration sensitivity in individuals with PHN aged 55–70 years compared to age‐matched healthy controls, using the Rydel—Seiffer graduated tuning fork. A prospective study of patients with acute zoster infection is needed to determine the sensitivity and specificity of the graduated tuning fork in predicting PHN in patients with acute zoster infection.

Neuropeptide Y(NPY) co‐exists with norepinephrine in the sympathetic nervous system, and NPY may represent the sympathetic‐neuronal output. Fibromyalgia syndrome (FMS) patients have perturbations in the hypothalmic‐pituitary‐adrenal (HPA) axis and in the sympathetic stress axis as well. As opioid peptides, monoamines and sex steroids are integrated in the regulation of stress, it is interesting to further explore the role of NPY in FMS patients, as they show many symptoms that are related to perturbations of those systems.

In this study, plasma NPY levels were assessed in subgroups of FMS patients: cyclic (regular menstrual cycles), non‐cyclic (post‐menopausal), depressed and non‐depressed patients. In order to examine whether pain and other symptoms seen in FMS patients are correlated to the NPY levels, the patients were also registering 15 different symptoms daily during 28 days. Sex and age‐matched healthy controls were recruited for comparisons. Non‐parametric tests were used for the statistical analyses.

The results showed that the NPY levels were significantly elevated in the patients compared to the controls. In the luteal phase of the cyclic patients, the levels of the peptide were higher than in the corresponding controls. For the non‐cyclic patients, there was a positive correlation between physical symptoms and NPY levels, however, pain per se did not reach the significant level of correlation. The non‐depressed patients had the same levels of NPY as the depressed FMS patients, who also had a positive correlation between anxiety and NPY levels.

These results suggest that FMS patients have an altered activity in the NPY system, most likely due to prolonged and/or repeated stress, and that the hormonal state and time of the menstrual cycle also may be of importance in the complex pathophysiologic mechanism behind the development of FMS.

Musculoskeletal pain is an outstanding symptom among the patients of primary health care. However, there are few studies of management and costs of musculoskeletal pain at primary health care level. The aim of this study was to describe the diagnostic investigations, management, referral rate and sick leaves related to visits prompted by musculoskeletal pain as well as to assess their costs. A total of 28 general practitioners (GPs) at 25 randomly selected health centres throughout Finland collected the data for this 4 week study, which covered 1 week from each of the four seasons. All visits, except those occurring after hours, were recorded. Altogether 1123 patients visited GPs because of musculoskeletal pain. Laboratory tests were ordered for 12% and imaging investigations for 24%. A total of 16% of the patients suffering from musculoskeletal pain received a prescription for physiotherapy, and analgesics were prescribed to 61% of them. Physicians referred 7% of the pain patients to specialist care. One out of every four patients was prescribed sick leave. The mean cost of the investigations, therapy, referrals, and sick leaves was as high as 530 EUR per visit, with absenteeism from work constituting two‐fifths of the total costs. Musculoskeletal pain is not just a frequent complaint but also has extensive economic consequences for society. Investigations and therapy at the primary health care level play a minor role in the costs as compared with specialist care and sick leaves. © 2002 European Federation of Chapters of the International Association for the Study of Pain