Preventive analgesia and novel strategies for the prevention of chronic post-surgical pain

Chronic post-surgical pain (CPSP) is a serious complication of major surgery that can impair a patient’s quality of life. The development of CPSP is a complex process which involves biologic, psychosocial, and environmental mechanisms that have yet to be fully understood. Currently perioperative pharmacologic interventions aim to suppress and prevent sensitization with the aim of reducing pain and analgesic requirement in acute as well as long-term pain . Despite the detrimental effects of CPSP on patients, the body of literature focused on treatment strategies to reduce CPSP remains limited and continues to be understudied. This article reviews the main pharmacologic candidates for the treatment of CPSP, discusses the future of preventive analgesia, and considers novel strategies to help treat acute postoperative pain and lessen the risk that it becomes chronic. In addition, this article highlights important areas of focus for clinical practice including: multimodal management of CPSP patients, psychological modifiers of the pain experience, and the development of a Transitional Pain Service specifically designed to manage patients at high risk of developing chronic post-surgical pain.HC is supported by a Merit Award (Department of Anaesthesia, University of Toronto) and the STAGE Training Program in Genetic Epidemiology (Canadian Institutes of Health Research, CIHR) and a grant by the Physicians Services Incorporated Foundation. JK is supported by a Canada Research Chair in Health Psychology. The authors of this manuscript have no conflicts of interest to declare

Acute and chronic post-surgical pain after living liver donation: Incidence and predictors

Despite its prominence as a concern among potential surgical candidates, there is little information in the literature regarding the short- and long-term pain experience after living liver donation. We undertook a prospective study to examine (1) the nature and incidence of acute and chronic pain after living donor hepatectomy and (2) the factors associated with an increased or decreased risk of adverse pain outcomes. Before donation, a comprehensive assessment of potential predictors of acute and chronic pain outcomes was conducted; this included donors’ pain expectations, psychosocial factors, medical histories, and demographic factors. Detailed data regarding pain outcomes were collected postoperatively (days 1 and 2) and again during 6- and 12-month follow-up telephone interviews. Sixty-five adults (32 females and 33 males) scheduled for donor hepatectomy participated. Substantial proportions of the donors reported a moderate-to-severe level of pain intensity (4 on a 0-10 scale) at rest and after movement on day 1 (42% and 74%, respectively) and day 2 (33% and 32%, respectively). Persistent postsurgical pain was reported by 31% of the donors at the 6-month follow-up and by 27% of the donors at the 12-month follow-up. Generally, this pain was mild, and pain-related life interference was minimal. Female sex, a younger age, and several predonation measures of pain-related anxiety were associated with a significantly greater risk of developing persistent postsurgical pain. In conclusion, this study has identified a subset of patients who experience persistent pain after living liver donation. Additional prospective research using larger samples of liver donors is needed to replicate this work, to obtain a more detailed account of the acute and long-term pain experience, and to determine whether targeted interventions can minimize the frequency and severity of chronic pain.Hance A. Clarke is supported by a merit award from the Department of Anesthesia at the University of Toronto and by the Strategic Training for Advanced Genetic Epidemiology program at the Canadian Institutes of Health Research. Joel Katz is supported as a Canadian Institutes of Health Research Canada Research Chair in Health Psychology at York University

Distinguishing problematic from nonproblematic postsurgical pain: A pain trajectory analysis after total knee arthroplasty

The goal of this study was to follow a cohort of patients undergoing total knee arthroplasty over time to: (1) identify and describe the various pain trajectories beginning preoperatively and for up to 12 months after surgery, (2) identify baseline predictors of trajectory group membership, and (3) identify trajectory groups associated with poor psychosocial outcomes 12 months after surgery. One hundred seventy-three participants (female = 85 [49%]; mean age [years] = 62.9, SD = 6.8) completed pain and psychological questionnaires and functional performance tests preoperatively and 4 days, 6 weeks, and 3 and 12 months after total knee arthroplasty. Using growth mixture modeling, results showed that a 4-group model, with a quadratic slope and baseline pain data predicting trajectory group membership, best fit the data (Akaike information criterion = 2772.27). The first 3 pain trajectories represent various rates of recovery ending with relatively low levels of pain 12 months after surgery. Group 4, the constant high pain group, comprises patients who have a neutral or positive pain slope and do not show improvement in their pain experience over the first year after surgery. This model suggests that preoperative pain levels are predictive of pain trajectory group membership and moderate preoperative pain, as opposed to low or high pain, is a risk factor for a neutral or positive pain trajectory postoperatively. Consistent with previous studies, these results show that postoperative pain is not a homogeneous condition and point to the importance of examining intraindividual pain fluctuations as they relate to pain interventions and prevention strategies.M. G. Page´ is supported by a Canada Graduate Scholarship— Doctoral Award from the Canadian Institutes of Health Research (CIHR) and is a recipient of a Lillian-Wright Maternal-Child Health Scholarship from York University, a trainee member of Pain in Child Health and a CIHR Strategic Training Fellow in Pain: Molecules to Community. J. Katz is supported by a CIHR Canada Research Chair in Health Psychology at York University. H. A. Clarke is supported by a Merit Award from the Department of Anaesthesia at the University of Toronto and also supported by the STAGE Training Program in Genetic Epidemiology from the CIHR. The remaining authors have no conflicts of interest to declare

Continuous regional anaesthesia provides effective pain management and reduces opioid requirement following major lower limb amputation

Objectives: Postoperative stump pain after major lower limb amputation is a significant impediment to the recovery of amputees. The vast majority of patients require opioid analgesics following surgery, which are associated with opioid-related side-effects. Here, we investigate whether intraoperative placement of a peripheral nerve stump catheter followed by continuous infusion of local anesthetic is as effective at pain control as current analgesic practices. If beneficial, this procedure could potentially reduce post-amputation opioid consumption and opioid-related adverse effects. Methods: A retrospective chart review was conducted of 198 patients over a 4-year period who had undergone a major lower limb amputation for indications related to peripheral vascular disease. Postoperatively, 102 patients received a perineural catheter were compared to 96 patients who did not. The primary outcomes of this study were the amount of morphine equivalents used in the first 72 hours postoperatively and postoperative pain intensity in the first 24 hours. Results: A total of 198 lower-limb amputations were selected for analyses. Multiple regression analyses indicated that perineural catheter use was associated with a lower cumulative postoperative opioid consumption over the first 72 hours but not postoperative pain scores at 24 hours. Perineural catheter use led to a 40% reduction in opioid use during the first 72 hours postoperatively. Mixed model repeated measures analysis demonstrated that this opioid reduction was consistent over time. Other variables related to total opioid use included age, presurgical chronic pain, pre-surgical opioid use, patient-controlled analgesia. Conclusions: Continuous perineural infusions of local anesthetic are a safe and effective method for reducing post-amputation opioid analgesic medications after major lower limp amputation.This study was supported by Canadian Society for Vascular Surgery 2013 National Student Research Award

Epidural Analgesia Provides Better Pain Management After Live Liver Donation: A Retrospective Study

Despite the increase in surgical volumes of live liver donation, there has been very little documentation of the postoperative pain experience. The primary aim of this study was to examine the difference in acute postoperative pain intensity and adverse effects between patients who received intravenous patient-controlled analgesia (IV PCA) or patient-controlled epidural analgesia (PCEA) for pain control after live liver donation surgery. A retrospective chart review was performed of 226 consecutive patients who underwent right living donor hepatic surgery at the Toronto General Hospital, Toronto, Canada. Patients who received as their primary postoperative analgesic modality IV PCA (n = 158) were compared to patients who received PCEA (n = 68). Demographic profiles for the 2 groups were similar with respect to age, sex, and body mass index at the time of surgery. For the first 3 postoperative days, pain intensity was significantly lower in patients who received epidural analgesia (P 4) was reported more frequently in the IV PCA group (P < 0.05) along with increased sedation (P < 0.05). Pruritus was reported more frequently in the PCEA group of patients compared to the IV PCA group (P < 0.05). Significant between-group differences were not found for the incidence of postoperative vomiting, the time at which patients began fluid intake, the time to initial ambulation, or the length of hospital stay. In conclusion, epidural analgesia provides better postoperative pain relief, less sedation, but more pruritus than IV PCA after live liver donation

The Prevention of Chronic Postsurgical Pain Using Gabapentin and Pregabalin: A Combined Systematic Review and Meta-Analysis

BACKGROUND: Many clinical trials have demonstrated the effectiveness of gabapentin and pregabalin administration in the perioperative period as an adjunct to reduce acute postoperative pain. However, very few clinical trials have examined the use of gabapentin and pregabalin for the prevention of chronic postsurgical pain (CPSP). We (1) systematically reviewed the published literature pertaining to the prevention of CPSP ( 2 months after surgery) after perioperative administration of gabapentin and pregabalin and (2) performed a meta-analysis using studies that report sufficient data. A search of electronic databases (Medline, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, IPA, and CINAHL) for relevant English-language trials to June 2011 was conducted. METHODS: The following inclusion criteria for identified clinical trials were used for entry into the present systematic review: randomization; double-blind assessments of pain and analgesic use; report of pain using a reliable and valid measure; report of analgesic consumption; and an absence of design flaws, methodological problems or confounders that render interpretation of the results ambiguous. Trials that did not fit the definition of preventive analgesia and did not assess chronic pain at 2 or more months after surgery were excluded. RESULTS: The database search yielded 474 citations. Eleven studies met the inclusion criteria. Of the 11 trials, 8 studied gabapentin, 4 of which (i.e., 50%) found that perioperative administration of gabapentin decreased the incidence of chronic pain more than 2 months after surgery. The 3 trials that used pregabalin demonstrated a significant reduction in the incidence of CPSP, and 2 of the 3 trials also found an improvement in postsurgical patient function. Eight studies were included in a meta-analysis, 6 of the gabapentin trials demonstrated a moderateto- large reduction in the development of CPSP (pooled odds ratio [OR] 0.52; 95% confidence interval [CI], 0.27 to 0.98; P 0.04), and the 2 pregabalin trials found a very large reduction in the development of CPSP (pooled OR 0.09; 95% CI, 0.02 to 0.79; P 0.007). CONCLUSIONS: The present review supports the view that perioperative administration of gabapentin and pregabalin are effective in reducing the incidence of CPSP. Better-designed and appropriately powered clinical trials are needed to confirm these early findings.Hance Clarke is supported by a Canadian Institutes of Health Research PhD Fellowship Award. Hance Clarke and Duminda Wijeysundera are supported by Merit Awards from the Department of Anesthesia at the University of Toronto. Duminda Wijeysundera is supported by a Clinician Scientist Award from the Canadian Institutes of Health Research. Joel Katz is supported by a Canada Research Chair in Health Psychology at York University

The GoodHope Exercise and Rehabilitation (GEAR) Program for People With Ehlers-Danlos Syndromes and Generalized Hypermobility Spectrum Disorders

Introduction: The Ehlers-Danlos Syndromes (EDS) and Generalized Hypermobility Spectrum Disorders (G-HSD) comprise a heterogeneous group of genetic disorders of abnormal synthesis and/or maturation of collagen and other matricellular proteins. EDS is commonly characterized by manifestations such as multi joint hypermobility that can lead to musculoskeletal pains, subluxations and dislocations, fragile skin, organ dysfunction, and chronic significant diffuse pain with fatigue, deconditioning eventuating to poor quality of life. Evidence suggests exercise and rehabilitation interventions may ameliorate symptoms of unstable joints, recurrent subluxations/dislocations, and chronic widespread musculoskeletal pain. To date, there have only been a few reports describing exercise and rehabilitation care strategies for people with EDS.Methods: In this manuscript, we describe the GoodHope Exercise and Rehabilitation (GEAR) program, its overarching principles, as well as the program development and delivery model. The GEAR program aims to decrease functional impairment, reduce pain, increase confidence in symptom self-management, and provide a community of support for people with EDS/G-HSD. To achieve these goals, we detail the model of care that includes exercise and rehabilitation therapy, education for self-management, and support accessing relevant community resources.Strengths and Limitations of the Study: GEAR represents a novel exercise and rehabilitation care model for people with G-HSD and various clinical EDS subtypes, beyond the commonly included hEDS subtype. Systematic collection of data via validated measurements is ongoing and will guide the refinement of GEAR and support the development of emerging exercise and rehabilitation programs for people with EDS

Medial open transversus abdominis plane (MOTAP) catheters for analgesia following open liver resection: study protocol for a randomized controlled trial

Background: The current standard for pain control following liver surgery is intravenous, patient-controlled analgesia (IV PCA) or epidural analgesia. We have developed a modification of a regional technique called medial open transversus abdominis plane (MOTAP) catheter analgesia. The MOTAP technique involves surgically placed catheters through the open surgical site into a plane between the internal oblique muscle and the transverse abdominis muscle superiorly. The objective of this trial is to assess the efficacy of this technique. Methods/design: This protocol describes a multicentre, prospective, blinded, randomized controlled trial. One hundred and twenty patients scheduled for open liver resection through a subcostal incision will be enrolled. All patients will have two MOTAP catheters placed at the conclusion of surgery. Patients will be randomized to one of two parallel groups: experimental (local anaesthetic through MOTAP catheters) or placebo (normal saline through MOTAP catheters). Both groups will also receive IV PCA. The primary endpoint is mean cumulative postoperative opioid consumption over the first 2 postoperative days (48 hours). Secondary outcomes include pain intensity, patient functional outcomes, and the incidence of complications. Discussion: This trial has been approved by the ethics boards at participating centres and is currently enrolling patients. Data collection will be completed by the end of 2014 with analysis mid-2015 and publication by the end of 2015. Trial registration: The study is registered with http://clinicaltrials.gov (NCT01960049; 23 September 2013)This research is supported by the Innovation Fund of the Alternative Funding Plan from the Academic Health Sciences Centres of Ontario

Effect of total-body prehabilitation on postoperative outcomes: A systematic review and meta-analysis

Objective To systematically review the evidence of pre-operative exercise, known as ‘prehabilitation’, on peri- and postoperative outcomesin adult surgical populations.Design Systematic review and meta-analysis.Data sources CENTRAL, Medline, EMBASE, CINAHL, PsycINFO and PEDro were searched from 1950 to 2011.Methods Two reviewers independently examined relevant, English-language articles that examined the effects of pre-operative total-bodyexercise with peri- and postoperative outcome analysis. Given the nascence of this field, controlled and uncontrolled trials were included. Riskof bias was assessed using the Cochrane Risk of Bias Assessment tool. Only data on length of stay were considered eligible for meta-analysisdue to the heterogeneity of measures and methodologies for assessing other outcomes.Results In total, 4597 citations were identified by the search strategy, of which 21 studies were included. Trials were generally small(median = 54 participants) and of moderate to poor methodological quality. Compared with standard care, the majority of studies found thattotal-body prehabilitation improved postoperative pain, length of stay and physical function, but it was not consistently effective in improvinghealth-related quality of life or aerobic fitness in the studies that examined these outcomes. The meta-analysis indicated that prehabilitationreduced postoperative length of stay with a small to moderate effect size (Hedges’ g = −0.39, P = 0.033). Intervention-related adverse eventswere reported in two of 669 exercising participants.Conclusion The literature provides early evidence that prehabilitation may reduce length of stay and possibly provide postoperative physicalbenefits. Cautious interpretation of these findings is warranted given modest methodological quality and significant risk of bias.© 2013 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.DSM is funded by the Princess Margaret Foundation viathe Prostate Centre for post-doctoral research, not specific tothis study