Pilot field testing of the chronic pain classification for ICD-11: the results of ecological coding.

BACKGROUND: A task force of the International Association for the Study of Pain (IASP) has developed a classification of chronic pain for the ICD-11 consisting of seven major categories. The objective was to test whether the proposed categories were exhaustive and mutually exclusive. In addition, the perceived utility of the diagnoses and the raters' subjective diagnostic certainty were to be assessed. METHODS: Five independent pain centers in three continents coded 507 consecutive patients. The raters received the definitions for the main diagnostic categories of the proposed classification and were asked to allocate diagnostic categories to each patient. In addition, they were asked to indicate how useful they judged the diagnosis to be from 0 (not at all) to 3 (completely) and how confident they were in their category allocation. RESULTS: The two largest groups of patients were coded as either chronic primary pain or chronic secondary musculoskeletal pain. Of the 507 patients coded, 3.0% had chronic pain not fitting any of the proposed categories (97% exhaustiveness), 20.1% received more than one diagnosis. After adjusting for double coding due to technical reasons, 2.0% of cases remained (98% uniqueness). The mean perceived utility was 1.9 ± 1.0, the mean diagnostic confidence was 2.0 ± 1.0. CONCLUSIONS: The categories proved exhaustive with few cases being classified as unspecified chronic pain, and they showed themselves to be mutually exclusive. The categories were regarded as useful with particularly high ratings for the newly introduced categories (chronic cancer-related pain among others). The confidence in allocating the diagnoses was good although no training regarding the ICD-11 categories had been possible at this stage of the development.

Acute pain management: scientific evidence, fourth edition, 2015.

This guideline summary describes the fourth edition of Acute pain management: scientific evidence, which was published by the Australian and New Zealand College of Anaesthetists (ANZCA) and its Faculty of Pain Medicine (FPMANZCA) in December 2015. The fourth edition summarises the best available evidence on acute pain management, following methods established over the preceding three editions. It provides additional information by scoring the quality of and reporting further details on randomised controlled trials and meta-analyses. The information is condensed into key messages that provide: concise statements on each topic, showing the highest level of evidence; and clinical practice points based on clinical experience or expert opinion.

Impact of epidural analgesia on mortality and morbidity after surgery: systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: To quantify benefit and harm of epidural analgesia, compared with systemic opioid analgesia, in adults having surgery under general anesthesia. BACKGROUND: It remains controversial whether adding epidural analgesia to general anesthesia decreases postoperative morbidity and mortality. METHODS: We searched CENTRAL, EMBASE, PubMed, CINAHL, and BIOSIS till July 2012. We included randomized controlled trials comparing epidural analgesia (with local anesthetics, lasting for ≥ 24 hours postoperatively) with systemic analgesia in adults having surgery under general anesthesia, and reporting on mortality or any morbidity endpoint. RESULTS: A total of 125 trials (9044 patients, 4525 received epidural analgesia) were eligible. In 10 trials (2201 patients; 87 deaths), reporting on mortality as a primary or secondary endpoint, the risk of death was decreased with epidural analgesia (3.1% vs 4.9%; odds ratio, 0.60; 95% confidence interval, 0.39-0.93). Epidural analgesia significantly decreased the risk of atrial fibrillation, supraventricular tachycardia, deep vein thrombosis, respiratory depression, atelectasis, pneumonia, ileus, and postoperative nausea and vomiting, and also improved recovery of bowel function, but significantly increased the risk of arterial hypotension, pruritus, urinary retention, and motor blockade. Technical failures occurred in 6.1% of patients. CONCLUSIONS: In adults having surgery under general anesthesia, concomitant epidural analgesia reduces postoperative mortality and improves a multitude of cardiovascular, respiratory, and gastrointestinal morbidity endpoints compared with patients receiving systemic analgesia. Because adverse effects and technical failures cannot be ruled out, individual risk-benefit analyses and professional care are recommended.

Nonopioid analgesics for postoperative pain management.

PURPOSE OF REVIEW: Postoperative pain remains poorly treated in many patients. One reason is the inadequate use of nonopioid analgesics. This review examines the most recent findings on nonopioid analgesics and how these translate into clinical practice. RECENT FINDINGS: Commonly used nonopioid analgesics are paracetamol, NSAIDs and metamizol (dipyrone). For paracetamol, the efficacy is obviously inferior to NSAIDs and the risk of adverse events might have been underestimated in the past. For NSAIDs, there are increasing data supporting similar efficacy of nonselective and cyclooxygenase-2 selective NSAIDs, although the adverse effects of the latter might make them the preferred option for short-term use in the perioperative setting. Metamizol (dipyrone) is a very effective nonopioid analgesic not worldwide available; the discussion on the relevance of the very rare adverse event agranulocytosis continues. SUMMARY: Nonopioid analgesics are important components of multimodal postoperative analgesia. The selection of the most appropriate compound for an individual patient can be based more and more on ever increasing data on these important analgesics.

Perioperative analgesia in pediatric surgery.

PURPOSE OF REVIEW: Poor pain management has continued to be a problem after pediatric surgery. This review examines the current situation and recent advances in the area. RECENT FINDINGS: Nonopioids such as paracetamol and NSAIDs play an increasing role as components of multimodal analgesia in children. However, studies on the safety and efficacy of many adjuvants in pediatrics are still lacking. The use of opioids is influenced understandably by safety concerns about respiratory depression, but data on its incidence are poor. The role of regional techniques in the treatment of pain after pediatric surgery is growing in line with the developments in adults; the emphasis here is more on peripheral techniques too. SUMMARY: The concept of multimodal analgesia including the use of regional analgesic techniques is governing the current developments and discussions in the area of pediatric postoperative analgesia.

Training general practitioners in remote Western Australia in a method of screening and brief intervention for harmful alcohol use: a pilot study.

OBJECTIVE: High levels of alcohol-related harm are a salient feature of many rural communities in Australia. General practitioners (GPs) are uniquely placed to identify and treat patients with harmful alcohol use in remote settings, yet corresponding opportunities for education in effective brief psychological interventions for harmful alcohol use are limited. This study piloted a training model for alcohol screening and brief intervention for GPs working in Kalgoorlie-Boulder, a remote Western Australian community facing significant alcohol-related problems. DESIGN: Observational pilot study. SETTING: Primary care. MAIN OUTCOME MEASURE(S): Perceived role in responding to harmful alcohol use, and confidence and knowledge of alcohol screening and brief intervention; satisfaction with a short training session focused on alcohol screening and brief intervention; and impact of training on implementation of screening and brief intervention for harmful alcohol use. RESULTS: Fifty per cent of GPs took up the training opportunity. GPs recognised their professional responsibility for conducting brief intervention but reported comparatively lower confidence and skills in implementing screening and intervention prior to training. The training improved knowledge and confidence in conducting alcohol screening and brief intervention. All GPs increased their frequency of alcohol screening, and 88% of GPs reported increasing the frequency of brief intervention at 6 months. CONCLUSIONS: Preliminary findings suggest that among participating GPs, subsequent compliance with identification and management of harmful alcohol use was improved. Further work examining methods to improve rural and remote GP participation in alcohol-related harm prevention training is required, as the potential impact on communities with disproportionately high alcohol-related difficulties is significant.

A review of the efficacy, safety, and cost-effectiveness of COX-2 inhibitors for Africa and the Middle East region.

Despite an increasingly sophisticated understanding of pain mechanisms, acute and chronic pain remain undertreated throughout the world. This situation reflects the large gap that exists between evidence and practice in pain management and is typified by inappropriate use of nonsteroidal anti-inflammatory drugs (NSAIDs). The scientific evidence around these drugs continues to expand at a high rate, yet physicians are often unaware of best practice. To address this gap among physicians in Africa and the Middle East, an Expert Panel meeting was convened with representatives from the region. The principal objective of the meeting was to review the latest guidelines on the management of acute and chronic pain and to review the efficacy, safety, and cost-effectiveness of cyclooxygenase-2 (COX-2) inhibitors in these settings. The main outcome of this review process was a number of consensus statements concerning the definitions of acute and chronic pain, and the efficacy, safety and cost-effectiveness of traditional nonselective NSAIDs (nsNSAIDs) and selective COX-2 inhibitors (coxibs). The panel agreed that nsNSAIDs and coxibs are effective analgesics with similar efficacy for acute pain; for chronic musculoskeletal pain, NSAIDs are significantly more effective than either placebo or paracetamol. Coxibs offer important safety advantages over nsNSAIDs, including gastrointestinal safety and preservation of platelet function; notably, the cardiovascular safety of coxibs has been the subject of much recent debate. Furthermore, the panel agreed there is substantial evidence to indicate that cost savings can be achieved by using celecoxib in patients at moderate to high risk of gastrointestinal adverse events, even in countries with moderate healthcare expenditures.

Serum lidocaine (lignocaine) concentrations during prolonged perioperative infusion in patients undergoing breast cancer surgery: A secondary analysis of a randomised controlled trial.

Perioperative lidocaine (lignocaine) infusions are being employed with increasing frequency. The determinants of systemic lidocaine concentrations during prolonged administration are unclear. In the Long-term Outcomes after Lidocaine Infusions for PostOperative Pain (LOLIPOP) pilot trial, the impact of infusion duration and body size metrics on serum lidocaine concentrations was examined with regression models in 48 women undergoing breast cancer surgery. Lidocaine was delivered as an intravenous bolus (1.5 mg/kg) and infusion (2 mg/kg per h) intraoperatively, followed by a 12-h subcutaneous infusion (1.33 mg/kg per h) postoperatively. Dosing was based on total body weight. Wound infiltration with other long-acting local anaesthetics was permitted. Protein binding and pharmacogenomic data were also collected. Lidocaine concentrations (median (interquartile range) (range)) during prolonged administration were in the safe and potentially therapeutic range: post-anaesthesia care unit 2.16 (1.73-2.82) (1.12-6.06) µg/ml; ward 1.41 (1.22-1.75) (0.64-2.81) µg/ml. Concentrations increased non-linearly during the early intravenous phase of administration (mean rise 1.21 µg/ml per hour of infusion, P = 0.007) but reached a pseudo steady-state during the later subcutaneous phase. Higher dose rates received per kilogram of lean (P = 0.004), adjusted (P = 0.006) and ideal body weight (P = 0.009) were associated with higher steady-state concentrations. The lidocaine free fraction was unaffected by the presence of ropivacaine, and phenotypes linked to slow metabolism were infrequent. Serum lidocaine concentrations reached a pseudo steady-state during a 12-h postoperative infusion. Greater precision in steady-state concentrations can be achieved by dosing on lean body weight versus adjusted or ideal body weight (equivalent lean body weight doses: intravenous bolus 2.5 mg/kg; intravenous infusion 3.33 mg/kg per h; subcutaneous infusion 2.22 mg/kg per h.

Low-dose sublingual ketamine does not modulate experimentally induced mechanical hyperalgesia in healthy subjects.

OBJECTIVE: Musculoskeletal pain has been associated with N-methyl-d-aspartate (NMDA) receptor-mediated mechanisms. This randomized controlled trial (RCT) investigated the effect of the NMDA receptor antagonist ketamine (25 mg sublingually) on modulating experimental muscle pain. DESIGN: Two groups (N = 11/group) of age- and sex-matched healthy subjects performed eccentric exercise using the nondominant arm wrist extensors (time 0) to induce muscle soreness 24 hours later (time 1). INTERVENTION: Immediately prior to exercise, subjects were administered either a 25 mg ketamine lozenge or a placebo. At time 1, experimental muscle pain was augmented by injection of hypertonic saline into the extensor carpi radialis brevis (ECRB) muscle of the exercised arm. OUTCOME MEASURES: Pressure pain thresholds (PPTs), muscle soreness, muscle pain intensity (electronic visual analog scale [VAS]), and maximal wrist extension force were assessed at time 0 (pre- and postexercise) and at time 1 (pre-, during, and post saline-induced pain). RESULTS: Regardless of group, PPT was reduced at ECRB (P < 0.021) and at the common extensor origin (P < 0.034) at time 1 preinjection compared with time 0 pre-exercise. At time 1, elevated levels of muscle soreness and force attenuation were similar between groups compared with time 0 pre-exercise (P < 0.0001), and similar hypertonic saline-induced pain areas and pain intensity profiles were evident. CONCLUSION: In comparison with placebo, a single low-dose sublingual pharmacological intervention targeting the processes of sensitization via antagonism of NMDA receptors did not modulate the effects of acute experimentally induced mechanical hyperalgesia, suggesting a higher dose or repeat doses may be required.

A phase I pharmacokinetic and bioavailability study of a sublingual fentanyl wafer in healthy volunteers.

BACKGROUND: The sublingual administration of opioids is a simple and noninvasive method that provides rapid analgesia. In this phase I study we investigated the pharmacokinetics and bioavailability of a fentanyl wafer in healthy volunteers. The principal study objective was to investigate the pharmacokinetic profile of a new sublingual fentanyl wafer and to establish its absolute bioavailability. METHODS: Twenty-four healthy volunteers, mean age 23 years, were randomly assigned to receive the equivalent of fentanyl 100 µg by both the sublingual and IV routes. Blood samples were collected in sterile polypropylene tubes for 24 hours after each fentanyl administration. The pharmacokinetic parameters were determined by model-independent pharmacokinetic analyses of the plasma fentanyl concentration-time profiles. RESULTS: The mean absolute bioavailability of the sublingual fentanyl wafer was 78.9% (90% confidence interval [CI] 51.1% to 121.7%). The first detectable plasma fentanyl concentration time ranged from 2 to 10 minutes in all volunteers, and the mean (±SD) time to peak plasma concentration at 0.91 (±0.73) hours after administration. CONCLUSION: Sublingual administration of fentanyl as a wafer product resulted in rapidly detectable plasma fentanyl concentrations. The absolute bioavailability of 78.9% indicated a high systemic availability of fentanyl and suggests that further development of this wafer is justified.

Evaluating Adherence of Evidence-Based Post-Operative Discharge Opioid Prescribing Guidelines and Patient Outcomes Two Weeks Post-Discharge.

Introduction: There is a growing public health concern regarding inappropriate prescribing practices of discharge analgesia. A tertiary Australian hospital first developed its Postoperative Inpatients Discharge Analgesia Guidelines after an initial audit in 2015. Adherence to the guidelines were evaluated in 2016 and 2017 which show reduced compliance from 93.5% in 2016 to 83.4% in 2017. Aim: To assess ongoing compliance with the guidelines five years following its implementation and to evaluate patient outcome in terms of its clinical impact and minimization of harmful events. Methods: Prescribing data were obtained for discharge analgesic medication for 200 surgical patients from August 2019 to April 2020. Records were assessed against the hospital's Postoperative Inpatients Discharge Analgesia Guidelines and compared with equivalent data from the previous 2015, 2016, and 2017 audits. Patients were interviewed by telephone two weeks after hospital discharge. Results: Prescribing of analgesia was most compliant with overall guidelines for paracetamol (100% unchanged from 2017), followed by celecoxib (98%, up from 96% in 2017), tramadol IR (89% up from 74% in 2017), and pregabalin (89% up from 50% in 2017). Two weeks after discharge, 112 (56%) patients were surveyed and reported a mean pain-score of 2 (95% CI 1.5-2.5) out of 10 at that time. Thirty-two (29%) patients interviewed were still taking pain medication, with 17 (53%) taking medication supplied from the hospital. Seventy-eight (88%) patients stored their pain medication in an unlocked location. Among those no longer taking analgesia, 28 (43%) had unused pain medications, and only two (6%) had returned these to a community pharmacist. Conclusion: This study found that compliance with hospital discharge analgesia prescribing guidelines has increased, although there is room for improvement. Follow-up of the participants reveals high rates of unused opioids, improper storage and disposal of their pain medication.

Preclinic group education sessions reduce waiting times and costs at public pain medicine units.

OBJECTIVE: To assess the effects of preclinic group education sessions and system redesign on tertiary pain medicine units and patient outcomes. DESIGN: Prospective cohort study. SETTING: Two public hospital multidisciplinary pain medicine units. PATIENTS: People with persistent pain. INTERVENTIONS: A system redesign from a "traditional" model (initial individual medical appointments) to a model that delivers group education sessions prior to individual appointments. Based on Patient Triage Questionnaires patients were scheduled to attend Self-Training Educative Pain Sessions (STEPS), a two day eight hour group education program, followed by optional patient-initiated clinic appointments. OUTCOME MEASURES: Number of patients completing STEPS who subsequently requested individual outpatient clinic appointment(s); wait-times; unit cost per new patient referred; recurrent health care utilization; patient satisfaction; Global Perceived Impression of Change (GPIC); and utilized pain management strategies. RESULTS: Following STEPS 48% of attendees requested individual outpatient appointments. Wait times reduced from 105.6 to 16.1 weeks at one pain unit and 37.3 to 15.2 weeks at the second. Unit cost per new patient appointed reduced from $1,805 Australian Dollars (AUD) to AUD$541 (for STEPS). At 3 months, patients scored their satisfaction with "the treatment received for their pain" more positively than at baseline (change score=0.88; P=0.0003), GPIC improved (change score=0.46; P<0.0001) and mean number of active strategies utilized increased by 4.12 per patient (P=0.0004). CONCLUSIONS: The introduction of STEPS was associated with reduced wait-times and costs at public pain medicine units and increased both the use of active pain management strategies and patient satisfaction.

Perioperative pain management after thoracotomy.

PURPOSE OF REVIEW: Perioperative acute pain and the development of persistent pain after thoracotomy are major problems severely affecting health-related quality of life. This review examines and highlights recent strategies and advances in perioperative pain management in this field. RECENT FINDINGS: Despite the fact that thoracic epidural analgesia (TEA) is considered the 'gold standard' of perioperative care after thoracotomy, other local and regional techniques have emerged within recent years and seem to become valid alternatives to TEA. The use of continuous paravertebral blockade, in particular, may provide similar analgesia and fewer adverse effects than TEA. Multimodal systemic approaches, including the use of ketamine and gabapentinoids are being investigated as well as the effect of surgical techniques and adjuvant therapies such as transcutaneous electrical nerve stimulation on post-thoracotomy pain. SUMMARY: Even though thoracotomy is associated with significant postoperative complications, a growing understanding of the underlying pathophysiology and advances in multimodal pain therapy concepts in this specific group of patients are promising improved postoperative outcomes and potential reduction of the incidence of persistent pain.

Do NSAIDs Really Interfere with Healing after Surgery?

Perioperative analgesia should be multimodal to improve pain relief, reduce opioid use and thereby adverse effects impairing recovery. Non-steroidal anti-inflammatory drugs (NSAIDs) are an important non-opioid component of this approach. However, besides potential other adverse effects, there has been a longstanding discussion on the potentially harmful effects of NSAIDs on healing after surgery and trauma. This review describes current knowledge of the effects of NSAIDs on healing of bones, cartilage, soft tissue, wounds, flaps and enteral anastomoses. Overall, animal data suggest some potentially harmful effects, but are contradictory in most areas studied. Human data are limited and of poor quality; in particular, there are only very few good randomized controlled trials (RCTs), but many cohort studies with potential for significant confounding factors influencing the results. The limited human data available are not precluding the use of NSAIDs postoperatively, in particular, short-term for less than 2 weeks. However, well-designed and large RCTs are required to permit definitive answers.

Efficacy and Tolerability of Oral Compared with Sublingual Ketamine Lozenges as Rescue Analgesics in Adults for Acute Pain: The OSKet Trial.

BACKGROUND AND OBJECTIVE: Ketamine is an N-methyl-D-aspartate receptor (NMDA) antagonist used widely as an intravenous analgesic for treatment of acute pain. Its use as oral and sublingual analgesics is not well studied. This study aims to compare the clinical efficacy and tolerability of oral (PO) versus sublingual (SL) ketamine lozenges in adult patients with moderate-to-severe breakthrough pain. METHODS: The study had a randomized, double-blind crossover design in 23 inpatients requiring ketamine as rescue analgesics when pain scores exceeded 4/10 on the Numerical Rating Scales. Each participant received either SL 50 mg ketamine lozenge and PO placebo lozenge or SL placebo lozenge and PO 50 mg ketamine lozenge in two treatment periods with a minimum 24-h washout. Pain scores and adverse effects were documented half hourly for the first 2 h, then one hourly for the next 2 h after treatment. The time to first effect and time to meaningful pain relief were recorded. Patients reported their satisfaction and a global impression of change (GIC) at the end of each treatment period. Data were analysed using random effects regression models. RESULTS: Sixteen subjects completed both days, 7 completed 1 day. Time to first effect was 13.1 min PO versus 6.6 min SL (p = 0.069), time to meaningful pain relief was 29.4 min PO versus 10.8 min SL (p = 0.02). Pain scores were not significantly different at all time points post-treatment. Satisfaction and GIC scores were similar for both groups. Overall, adverse events occurred more often with SL administration (p = 0.02). CONCLUSIONS: Sublingual administration of ketamine led to a faster onset of pain relief (but also a higher adverse event rate), but in all other aspects treatment with ketamine given sublingually and orally produced similar analgesic effects. ACTRN: ACTRN12621000240842, 08/03/2021, retrospectively registered.

Successful rotation from long-acting full agonist opioids to sublingual buprenorphine/naloxone using a microdosing approach.

Buprenorphine/naloxone (BPN/NX) is a first-line treatment for opioid use disorder. Conventional treatment guidelines recommend a period of opioid abstinence and the presence of moderate withdrawal before initiation to avoid precipitated withdrawal. A newer approach of "microdosing" removes this requirement and has potential benefits. We present two cases of successful induction of BPN/NX using a microdosing regimen in an inpatient withdrawal unit. Both cases did not result in precipitated withdrawal and did not necessitate prior cessation of other opioids. This case report highlights how the use of microdosing to induct BPN/NX treatment can reduce potential barriers and complications with treatment initiation.

Pregabalin for neuropathic pain in primary care settings: recommendations for dosing and titration.

Pregabalin is one of the first-line treatments approved for the management of neuropathic pain (NeP). While many patients benefit from treatment with pregabalin, they are often treated with suboptimal doses, possibly due to unfamiliarity around prescribing the drug and/or side effects that can occur with up-titration. This narrative review discusses key aspects of initiating, titrating, and managing patients prescribed pregabalin therapy, and addresses concerns around driving and the potential for abuse, as well as when to seek specialist opinion. To ensure that patients derive maximum therapeutic benefit from the drug, we suggest a 'low and slow' dosing approach to limit common side effects and optimize tolerability alongside patients' expectations. When requiring titration to higher doses, we recommend initiating 'asymmetric dosing,' with the larger dose in the evening. Fully engaging patients in order for them to understand the expected timeline for efficacy and side effects (including their resolution), can also help determine the optimal titration tempo for each individual patient. The 'low and slow' approach also recognizes that patients with NeP are heterogeneous in terms of their optimal therapeutic dose of pregabalin. Hence, it is recommended that general practitioners closely monitor patients and up-titrate according to pain relief and side effects to limit suboptimal dosing or premature discontinuation.

A survey of patients' use of the internet for chronic pain-related information.

OBJECTIVE: To investigate the use of the Internet as a pain information seeking tool among a population of patients attending a chronic pain clinic. METHODS: A bespoke self-completing questionnaire was given to 150 patients attending 17 consecutive chronic pain clinics at The Royal Perth Hospital during August and September 2007. RESULTS: One hundred twenty-two completed surveys were received, a response rate of 81%. Only 23.8% of the patients had used the Internet to access pain-related health care information. There was no gender difference between those who did and did not access the Internet for information. Age group, highest educational level attained, and the availability of Internet access were all significantly associated with the use of the Internet to search for pain-related information. 41.4% described the information they found as useful, 6.9% found it frightening and 10.3% found it confusing. Forty-four percent wanted more information to be available on the Internet while only 6.9% planned to discuss their findings with their doctor. CONCLUSIONS: When compared with other studies about patient information-seeking behavior, a smaller than expected percentage of patients attending chronic pain clinics in Perth used the Internet to search for information about pain. There are a variety of reasons for this that would suggest that health care professionals should not be complacent but seek to maximize the potential of the Internet to inform our patients by advising them how and where to look for relevant information.