Current status of preemptive analgesia.

PURPOSE OF REVIEW: The controversy over preemptive analgesia continues unabated, with studies both supporting and refuting its efficacy. The timing of an analgesic intervention and presence of a placebo control may have significant impact on the interpretation of results and may have led to the premature conclusion that preemptive analgesia is of limited clinical utility. A review of the recent literature using strict definitions of preemptive and preventive analgesia is required in order to clarify the broader issue of the benefits of perioperative analgesia. RECENT FINDINGS: A total of 27 studies, published from April 2001 to April 2002, were found to evaluate preemptive (n = 12) or preventive analgesia (n = 15). Evidence for a benefit of preventive analgesia was strong, with 60% of studies finding reduced pain or analgesic consumption beyond the clinical duration of action of the analgesic intervention. Evidence for a benefit of preemptive analgesia was equivocal, with 41.7% of studies demonstrating that preincisional treatment reduces pain or analgesic consumption to a greater extent than does postincisional treatment. SUMMARY: Studies that used a preventive design had a greater likelihood of finding a beneficial effect. The application of preventive perioperative analgesia (not necessarily preincisional) is associated with a significant reduction in pain beyond the clinical duration of action of the analgesic agent, in particular for the N-methyl-D-aspartate antagonists. The classical definition of preemptive analgesia should be abandoned in favor of preventive analgesia. This will broaden the scope of inquiry from a narrow focus on preincisional versus postincisional interventions to one that aims to minimize postoperative pain and analgesic requirements by reducing peripheral and central sensitization arising from noxious preoperative, intraoperative and postoperative inputs.Preparation of this manuscript was supported in part by grants MCT- 38144 and MOP-37845 from the Canadian Institutes of Health Research (CIHR) and a CIHR Investigator Award to Dr Katz

Systematic review of persistent pain and psychological outcomes following traumatic musculoskeletal injury

Background: Persistent pain and psychological distress are common after traumatic musculoskeletal injury (TMsI). Individuals sustaining a TMsI are often young, do not recover quickly, and place a large economic burden on society. Objectives: The aim of this systematic review is to determine (1) the incidence of persistent pain following TMsI, (2) the characteristics of pain, characterized by injury severity and type, and (3) risk and protective factors associated with persistent pain following TMsI. Methods: A systematic search of electronic databases (MEDLINE®, PubMed®, Embase, and PsycINFO®) was conducted for prospective, interventional, or noninterventional studies measuring the incidence of pain associated with TMsI. Results: The search revealed 4388 studies. Eleven studies examined persistent pain and met inclusion criteria. Pain was assessed using a validated measure of pain intensity or pain presence in six studies. Persistent pain was reported by all studies at variable time points up to 84 months postinjury, with wide variation among studies in pain intensity (ie, from mild to very severe) and pain incidence at each time point. The incidence of pain decreased over time within each study. Two studies found significant relationships between injury severity and persistent pain. Frequently cited predictive factors for persistent pain included: symptoms of anxiety and depression, patient perception that the injury was attributable to external sources (ie, they were not at fault), cognitive avoidance of distressing thoughts, alcohol consumption prior to trauma, lower educational status, being injured at work, eligibility for compensation, pain at initial assessment, and older age. Conclusion and implications: The evidence from the eleven studies included in this review indicates that persistent pain is prevalent up to 84 months following traumatic injury. Further research is needed to better evaluate persistent pain and other long-term posttraumatic outcomes.Joel Katz is supported by a Canadian Research Chair in Health Psychology at York University

Impact of Attending a Healthcare Conference in Toronto During the Severe Acute Respiratory Syndrome Crisis: Survey of Delegates

OBJECTIVE: To describe the impact on delegates of attending the Canadian Pain Society's annual meeting in Toronto during the severe acute respiratory syndrome (SARS) crisis in May 2003.METHODS: A prospective survey design was used. Surveys were sent to all delegates (n=432) who attended the conference, and 294 delegates responded (68% response rate). The survey was developed to determine the level of concern about travelling to Toronto; the adequacy of screening measures; the level of stress about attending; and the occupational consequences of attending.RESULTS: Fifty per cent of the participants were not concerned about travelling to Toronto, while the other 50% expressed some concern ranging from mild to serious. Concerns included being exposed to SARS and fear of transmitting it to others upon return. Reasons for attending the conference despite concern included a desire for continuing education, decrease in the number of reported SARS cases, and perceived minimal risk. Almost one-half (n=140) felt the screening measures at the conference were adequate, while 4% felt they were inadequate and 9% somewhat adequate. Delegates (n=99) suggested that temperature-taking (32.2%), improved screening vigilance (14.4%), SARS screening forms checked daily (9.1%), strictly controlled entry (8.1%) and adopting hospital screening procedures (7.1%) should have been instituted.CONCLUSION: Health care professionals planning conferences in this era of new respiratory diseases can benefit from understanding the responses of delegates who attended conferences during outbreaks. Clear communication about the potential risks and benefits, as well as instituting full screening precautions, will help to allay concerns.Peer Reviewe

Impact of Attending a Healthcare Conference in Toronto During the Severe Acute Respiratory Syndrome Crisis: Survey of Delegates

OBJECTIVE: To describe the impact on delegates of attending the Canadian Pain Society's annual meeting in Toronto during the severe acute respiratory syndrome (SARS) crisis in May 2003

Early but no long-term benefit of regional compared with general anesthesia for ambulatory hand surgery.

Background: The purpose of this study was to determine whether either regional anesthesia (RA) or general anesthesia (GA) provided the best analgesia with the fewest adverse effects up to 2 weeks after ambulatory hand surgery. Methods: Patients undergoing ambulatory hand surgery were randomly assigned to RA (axillary brachial plexus block; n = 50) or GA (n = 50). Before surgery, all patients rated their hand pain (visual analog scale) and pain-related disability (Pain-Disability Index). After surgery, eligibility for bypassing the postanesthesia care unit ("fast track") was determined, and pain, adverse effects, and home-readiness scores were measured. On postoperative days 1, 7, and 14, patients documented their pain, opioid consumption, adverse effects, Pain-Disability Index, and satisfaction. Results: More RA patients were fast-track eligible (P < 0.001), whereas duration of stay in the postanesthesia care unit was shorter in the RA group (P < 0.001). Time to first analgesic request was longer in the RA group (P < 0.001), and opioid consumption was reduced before discharge (P < 0.001). In the RA group, the pain ratings measured at 30, 60, 90, and 120 min after surgery were lower (P < 0.001), and patients spent less time in the hospital after surgery (P < 0.001). More GA patients experienced nausea/ vomiting during recovery in the hospital (P < 0.05). However, on postoperative days 1, 7, and 14, there were no differences in pain, opioid consumption, adverse effects, Pain-Disability Index, or satisfaction. Conclusions: Despite significant reduction in pain before discharge from the hospital after ambulatory hand surgery, singleshot axillary brachial plexus block does not reduce pain at home on postoperative day 1 or up to 14 days after surgery when compared with GA. However, RA does provide other significant early benefits, including reduction in nausea and faster discharge from the hospital

An Intensive Perioperative Regimen of Pregabalin and Celecoxib Reduces Pain and Improves Physical Function Scores Six Weeks after Total Hip Arthroplasty: A Prospective Randomized Controlled Trial

BACKGROUND: Despite the success of total hip arthroplasty (THA), some patients experience persistent pain and poor function after surgery. Predictors of poor outcomes include the presence of significant pre- and postoperative pain. Patients undergoing THA often experience severe, longstanding pain before surgery that may compromise the outcome of the procedure