Saifudin Rashiq

Disruption of attention and working memory traces in individuals with chronic pain

BACKGROUND: Research has found that chronic pain disrupts attention and that this disruption can lead to significant functional impairment and decreased quality of life. We conducted the present study to examine how attention and memory are disrupted by chronic pain. METHODS: Computerized tests of working memory were given to participants with chronic pain along with a neuropsychological test of attention before and after procedures resulting in analgesia. RESULTS: Two-thirds of participants with chronic pain had scores in the clinically impaired range on attentional tasks. These results were independent of age, education level, sleep disruption, and pain relief. Medication use was also recorded and is reported to account for potential effects of medication on task performance. Those participants with the highest level of impairment had significantly greater difficulties in maintaining a memory trace during a challenging test of working memory. CONCLUSIONS: These findings point to a specific cognitive mechanism, the maintenance of the memory trace, that is affected by chronic pain during task performance. Cognitive function was not improved by short-term local analgesia.

Disruption of cognitive function in Fibromyalgia Syndrome

Abstract Accumulating evidence points to significant cognitive disruption in individuals with Fibromyalgia Syndrome (FMS). This study was carried out in order to examine specific cognitive mechanisms involved in this disruption. Standardized experimental paradigms were used to examine attentional function and working memory capacity in 30 women with FMS and 30 matched controls. Cognitive function was examined using performance on these tests and between group results were analysed in the context of important psychological and behavioural measures. Performance of standardized everyday attentional tasks was impaired in the FMS group compared to controls. Working memory was also found to be impaired in this group. Stimulus interference was found to be significantly worse in the FMS group as the demands of the tasks increased. These effects were found to exist independent of the measures of mood and sleep disruption. However, when pain levels were accounted for statistically, no differences existed between groups on cognitive measures. These findings point to disrupted working memory as a specific mechanism that is disrupted in this population. The results of this study suggest that pain in FMS may play an important role in cognitive disruption. It is likely that many factors, including disrupted cognition, play a role in the reduced quality of life reported by individuals with FMS.

Buprenorphine transdermal system in adults with chronic low back pain: A randomized, double-blind, placebo-controlled crossover study, followed by an open-label extension phase

BACKGROUND Buprenorphine is a mixed-activity, partial mu-opioid agonist. Its lipid solubility makes it well suited for transdermal administration. OBJECTIVE This study assessed the efficacy and safety profile of a 7-day buprenorphine transdermal system (BTDS) in adult (age >18 years) patients with moderate to severe chronic low back pain previously treated with > or =1 tablet daily of an opioid analgesic. METHODS This was a randomized, double-blind, placebo-controlled crossover study, followed by an open-label extension phase. After a 2- to 7-day washout of previous opioid therapy, eligible patients were randomized to receive BTDS 10 microg/h or matching placebo patches. The dose was titrated weekly using 10- and 20-microg/h patches (maximum, 40 microg/h) based on efficacy and tolerability. After 4 weeks, patients crossed over to the alternative treatment for another 4 weeks. Patients who completed the double-blind study were eligible to enter the 6-month open-label phase. Rescue analgesia was provided as acetaminophen 325 mg to be taken as 1 or 2 tablets every 4 to 6 hours as needed. The primary outcome assessments were daily pain intensity, measured on a 100-mm visual analog scale (VAS), from no pain to excruciating pain, and a 5-point ordinal scale, from 0 = none to 4 = excruciating. Secondary outcome assessments included the Pain and Sleep Questionnaire (100-mm VAS, from never to always), Pain Disability Index (ordinal scale, from 0 = no disability to 11 = total disability), Quebec Back Pain Disability Scale (categorical scale, from 0 = no difficulty to 5 = unable to do), and the 36-item Short Form Health Survey (SF-36). Patients and investigators assessed overall treatment effectiveness at the end of each phase; they assessed treatment preference at the end of double-blind treatment. After implementation of a precautionary amendment, the QTc interval was measured 3 to 4 days after randomization and after any dose adjustment. All assessments performed during the double-blind phase were also performed every 2 months during the open-label extension. Adverse events were collected by non-directed questioning throughout the study. RESULTS Of 78 randomized patients, 52 (66.7%) completed at least 2 consecutive weeks of treatment in each study phase without major protocol violations (per-protocol [PP] population: 32 women, 20 men; mean [SD] age, 51.3 [11.4] years; mean weight, 85.5 [19.5] kg; 94% white, 4% black, 2% other). The mean (SD) dose of study medication during the last week of treatment was 29.8 (12.1) microg/h for BTDS and 32.9 (10.7) microg/h for placebo (P = NS). During the last week of treatment, BTDS was associated with significantly lower mean (SD) pain intensity scores compared with placebo on both the VAS (45.3 [21.3] vs 53.1 [24.3] mm, respectively; P = 0.022) and the 5-point ordinal scale (1.9 [0.7] vs 2.2 [0.8]; P = 0.044). The overall Pain and Sleep score was significantly lower with BTDS than with placebo (177.6 [125.5] vs 232.9 [131.9]; P = 0.027). There were no treatment differences on the Pain Disability Index, Quebec Back Pain Disability Scale, or SF-36; however, BTDS was associated with significant improvements compared with placebo on 2 individual Quebec Back Pain Disability Scale items (get out of bed: P = 0.042; sit in a chair for several hours: P = 0.022). Of the 48 patients/physicians in the PP population who rated the effectiveness of treatment, 64.6% of patients (n = 31) rated BTDS moderately or highly effective, as did 62.5% of investigators (n = 30). Among the 50 patients in the PP population who answered the preference question, 66.0% of patients (n = 33) preferred the phase in which they received BTDS and 24.0% (n = 12) preferred the phase in which they received placebo (P = 0.001), with the remainder having no preference; among investigators, 60.0% (n = 30) and 28.0% (n = 14) preferred the BTDS and placebo phases, respectively (P = 0.008), with the remainder having no preference. The mean placebo-adjusted change from baseline in the QTc interval ranged from -0.8 to +3.8 milliseconds (P = NS). BTDS treatment was associated with a significantly higher frequency of nausea (P < 0.001), dizziness (P < 0.001), vomiting (P = 0.008), somnolence (P = 0.020), and dry mouth (P = 0.003), but not constipation. Of the 49 patients completing 8 weeks of double-blind treatment, 40 (81.6%) entered the 6-month, open-label extension study and 27 completed it. Improvements in pain scores achieved during the double-blind phase were maintained in these patients. CONCLUSIONS In the 8-week, double-blind portion of this study, BTDS 10 to 40 microg/h was effective compared with placebo in the management of chronic, moderate to severe low back pain in patients who had previously received opioids. The improvements in pain scores were sustained throughout the 6-month, open-label extension. (Current Controlled Trials identification number: ISRCTN 06013881).

Selective ordering of preoperative investigations by anesthesiologists reduces the number and cost of tests

PurposePreoperative investigations are frequently ordered according to care maps or protocols. We hypothesized that selective ordering of investigations by anesthesiology staff would reduce the number and cost of testing.MethodsProspective descriptive double cohort study carried out over 17 weeks in a tertiary care preadmission clinic. In Group 1, testing followed usual practice (based on standing preoperative orders) while in Group 2 testing was initiated only on the order of an attending anesthesiologist or anesthesiology resident. Postoperative complications were categorized and confirmed by an internist blinded to group assignment. Fisher’s exact test, Chisquare and Student’s t test were used to compare the groups as appropriate. Statistical significance was inferred atP < 0.05.ResultsData were obtained from 507 patients in Group 1 and 431 patients in Group 2. Demographics and ASA risk score were similar in both groups. The mean number of tests ordered did not differ between groups. The mean cost of investigations was reduced from

Factors associated with chronic noncancer pain in the Canadian population

124 in Group 1 to

Buprenorphine transdermal system for opioid therapy in patients with chronic low back pain.

95 in Group 2 (P < 0.05). If data for patients assessed by staff anesthesiologists only were considered, the mean cost of testing was reduced to

Analgesic action of gabapentin on chronic pain in the masticatory muscles: A randomized controlled trial

73. The number and cost of tests ordered by anesthesia residents were similar to that in Group 1. More complications were noted in Group 2, but these did not appear to be related to the altered test ordering practice.ConclusionSelective test ordering by staff anesthesiologists reduces the number and cost of preoperative investigations. Educational efforts should be directed towards improving resident and staff preoperative test ordering practices.RésuméObjectifLes tests préopératoires sont souvent demandés pour satisfaire à des plans thérapeutiques ou à des protocoles. Nous avons émis l’hypothèse qu’une demande sélective de tests par les anesthésiologistes réduirait le nombre et le coût de ces tests.MéthodeUne étude prospective et descriptive de deux cohortes a été menée pendant 17 semaines dans une clinique de soins tertiaires. Dans le groupe 1, le protocole habituel a été suivi (fondé sur les règlements) tandis que dans le groupe 2, les tests ont été faits seulement sur ordre d’un anesthésiologiste traitant ou d’un résident en anesthésiologie. Les complications postopératoires ont été catégorisées et confirmées par un interniste impartial. Le test exact de Fisher, les tests du x2 et t de Student ont servi à comparer les groupes. Une signification statistique était considérée pourP < 0,05.RésultatsLes données ont été obtenues de 507 patients dans le groupe 1 et de 431 dans le groupe 2. Les données démographiques et la cotation des risques selon l’ASA, de même que le nombre de tests demandés étaient similaires dans les deux groupes. Le coût moyen des tests a été réduit de 124

Opioid prescriptions in canadian workers' compensation claimants: prescription trends and associations between early prescription and future recovery.

dans le groupe 1 à 95

Predicting allogeneic blood transfusion use in total joint arthroplasty.

dans le groupe 2 (P < 0,05). En ne tenant compte que des données évaluées par les anesthésiologistes traitants, le coût moyen était réduit à 73

A Critical Review of Neurobiological Factors Involved in the Interactions Between Chronic Pain, Depression, and Sleep Disruption.

. Le nombre et le coût des tests demandés par les résidents étaient similaires à ceux du groupe 1. Il y a eu plus de complications dans le groupe 2, mais elles ne semblaient pas reliées à une modification de la demande de tests.ConclusionLa demande sélective de tests par les anesthésiologistes traitants réduit le nombre et le coût des tests préopératoires. Il faudrait accentuer les efforts de formation visant à améliorer la pratique de demande de tests préopératoires par les résidents et le personnel traitant.