New approach for treatment of prolonged postoperative pain: APS Out-Patient Clinic

Evaluating pain management in older people after orthopaedic surgery - a study in Jordan

BACKGROUND

Pain management in older people presents unique challenges due to age-related physiological changes, altered responses to medicines, comorbidities and polypharmacy. These challenges, which are exacerbated in those aged ≥75 years, can compromise the efficacy and safety of pharmacological treatment, including after discharge following orthopaedic surgery.

AIM

To evaluate pain management and follow-up care provided in primary care settings in Jordan to older people who had undergone orthopaedic surgery.

METHOD

For this descriptive study, data were collected from the discharge summaries and electronic health records of older people who were receiving support from community nurses in rural primary care units in the Aqaba Governorate in Jordan after undergoing orthopaedic procedures in hospital.

RESULTS

Of the 100 participants, 63 lived in a nursing home and 30 had been diagnosed with dementia. Hip fractures, diagnosed in 56 participants, were the most common reason for surgery. Thirty-two participants had a documented post-discharge follow-up plan regarding pain management in primary care. Of the 90 participants who were still being followed up 12 weeks after discharge, 51 (57%) were still being prescribed opioids for regular use or as required.

CONCLUSION

Nurses have a crucial role in ensuring effective and safe pain management in older people, particularly when using opioids, due to the heightened risk of adverse effects and medicine interactions. Tailored pain management involves careful initiation of medicines; regular monitoring and assessment of pain levels, adherence to medicines and monitoring of potential side effects; and individualised follow-up plans.

Impact of a Transitional Pain Service on postoperative opioid trajectories: a retrospective cohort study

INTRODUCTION

It has been well described that a small but significant proportion of patients continue to use opioids months after surgical discharge. We sought to evaluate postdischarge opioid use of patients who were seen by a Transitional Pain Service compared with controls.

METHODS

We conducted a retrospective cohort study using administrative data of individuals who underwent surgery in Ontario, Canada from 2014 to 2018. Matched cohort pairs were created by matching Transitional Pain Service patients to patients of other academic hospitals in Ontario who were not enrolled in a Transitional Pain Service. Segmented regression was performed to assess changes in monthly mean daily opioid dosage.

RESULTS

A total of 209 Transitional Pain Service patients were matched to 209 patients who underwent surgery at other academic centers. Over the 12 months after surgery, the mean daily dose decreased by an estimated 3.53 morphine milligram equivalents (95% CI 2.67 to 4.39, p<0.001) per month for the Transitional Pain Service group, compared with a decline of only 1.05 morphine milligram equivalents (95% CI 0.43 to 1.66, p<0.001) for the controls. The difference-in-difference change in opioid use for the Transitional Pain Service group versus the control group was -2.48 morphine milligram equivalents per month (95% CI -3.54 to -1.43, p=0.003).

DISCUSSION

Patients enrolled in the Transitional Pain Service were able to achieve opioid dose reduction faster than in the control cohorts. The difficulty in finding an appropriate control group for this retrospective study highlights the need for future randomized controlled trials to determine efficacy.

Stepped collaborative care for pain and posttraumatic stress disorder after major trauma: a randomized controlled feasibility trial

PURPOSE

To examine feasibility and acceptability of providing stepped collaborative care case management targeting posttraumatic stress disorder (PTSD) and pain symptoms after major traumatic injury.

MATERIALS AND METHODS

Participants were major trauma survivors in Victoria, Australia, at risk of persistent pain or PTSD with high baseline symptoms. Participants were block-randomized, stratified by compensation-status, to the usual care (n = 15) or intervention (n = 17) group (46% of eligible patients). The intervention was adapted from existing stepped collaborative care interventions with input from interdisciplinary experts and people with lived experience in trauma and disability. The proactive case management intervention targeted PTSD and pain management for 6-months using motivational interviewing, cognitive behavioral therapy strategies, and collaborative care. Qualitative interviews explored intervention acceptability.

RESULTS

Intervention participants received a median of 7 h case manager contact and reported that they valued the supportive and non-judgmental listening, and timely access to effective strategies, resources, and treatments post-injury from the case manager. Participants reported few disadvantages from participation, and positive impacts on symptoms and recovery outcomes consistent with the reduction in PTSD and pain symptoms measured at 1-, 3- and 6-months.

CONCLUSIONS

Stepped collaborative care was low-cost, feasible, and acceptable to people at risk of PTSD or pain after major trauma.IMPLICATIONS FOR REHABILITATIONAfter hospitalization for injury, people can experience difficulty accessing timely support to manage posttraumatic stress, pain and other concerns.Stepped case management-based interventions that provide individualized support and collaborative care have reduced posttraumatic stress symptom severity for patients admitted to American trauma centers.We showed that this model of care could be adapted to target pain and mental health in the trauma system in Victoria, Australia.The intervention was low cost, acceptable and highly valued by most participants who perceived that it helped them use strategies to better manage post-traumatic symptoms, and to access clinicians and treatments relevant to their needs.

Discharge Opioid Dose Indirectly Associated With Functional Outcomes 2 Weeks After Shoulder and Knee Arthroscopy in a US Military Sample

INTRODUCTION

Postsurgical opioid utilization may be directly and indirectly associated with a range of patient-related and surgery-related factors, above and beyond pain intensity. However, most studies examine postsurgical opioid utilization without accounting for the multitude of co-occurring relationships among predictors. Therefore, this study aimed to identify factors associated with opioid utilization in the first 2 weeks after arthroscopic surgery and examine the relationship between discharge opioid prescription doses and acute postsurgical outcomes.

METHODS

In this prospective longitudinal observational study, 110 participants undergoing shoulder or knee arthroscopies from August 2016 to August 2018 at Walter Reed National Military Medical Center completed self-report measures before and at 14 days postoperatively. The association between opioid utilization and both patient-level and surgery-related factors was modeled using structural equation model path analysis.

RESULTS

Participants who were prescribed more opioids took more opioids, which was associated with worse physical function and sleep problems at day 14, as indicated by the significant indirect effects of discharge opioid dose on day 14 outcomes. Additional patient-level and surgery-related factors were also significantly related to opioid utilization dose and day 14 outcomes. Most participants had opioid medications leftover at day 14.

CONCLUSION

Excess opioid prescribing was common, did not result in improved pain alleviation, and was associated with poorer physical function and sleep 14 days after surgery. As such, higher prescribed opioid doses could reduce subacute functioning after surgery, without benefit in reducing pain. Future patient-centered studies to tailor opioid postsurgical prescribing are needed.

Transitional Pain Service: An Update

PURPOSE OF REVIEW

Chronic Postsurgical Pain (CPSP) and the risk for long-term opioid dependency are known complications following major surgery. The idea of Transitional Pain Service (TPS) has been introduced as an interdisciplinary setting to manage pain in the perioperative continuum. We expand on the basic framework and principles of TPS and summarize the current evidence of the TPS and possible interventions to adress postoperative pain. Areas of future work in TPS-related research are discussed.

RECENT FINDINGS

Several studies support the effectiveness of TPS in reducing opioid consumption in the perioperative period and following discharge. Some studies also show an improvement in functional outcome with TPS with patients reporting lower pain severity and pain interference. The TPS aims to halt the progress of acute postoperative pain to CPSP by providing longitudinal support with patient-centered care. While some studies suggest a positive impact of TPS implementation in terms of reduction in postoperative opioid consumption and improvement of some functional outcomes, direct evidence in terms of reduction in the incidence of CPSP is still missing. The cost-effectiveness of TPS and the expansion of TPS through e-health services and digital applications also need to be evaluated.

Perioperative pain management models in four European countries: A narrative review of differences, similarities and future directions

There is general agreement that acute pain management is an important component of perioperative medicine. However, there is no consensus on the best model of care for perioperative pain management, mainly because evidence is missing in many aspects. Comparing the similarities and differences between countries might reveal some insights into different organisational models and how they work. Here, we performed a narrative review to describe and compare the structures, processes and outcomes of perioperative pain management in the healthcare systems of four European countries using Donabedian's framework as a guide. Our comparison revealed many similarities, differences and gaps. Different structures of acute pain services in the four countries with no common definition and standards of care were found. Protocols have been implemented in all countries and guidelines in some. If outcome is assessed, it is mainly pain intensity, and many patients experiencing more intense pain than others have common risk factors (e.g. preoperative pain, preoperative opioid intake, female sex and young age). Outcome assessment beyond pain intensity (such as pain-related physical function, which is important for early rehabilitation and recovery) is currently not well implemented. Developing common quality indicators, a European guideline for perioperative pain management (e.g. for patients at high risk for experiencing severe pain and other outcome parameters) and common criteria for acute pain services might pave the way forward for improving acute pain management in Europe. Finally, the education of general and specialist staff should be aligned in Europe, for example, by using the curricula of the European Pain Federation (EFIC).

The effectiveness of a transitional pain service in patients undergoing surgery with an increased risk of developing chronic postsurgical pain (TRUSt study). A randomized clinical trial

STUDY OBJECTIVE

Poorly controlled acute postsurgical pain is associated with delayed recovery, chronic postsurgical pain (CPSP), chronic opioid use and impaired functioning in daily activities. The aim was to determine the effectiveness of a transitional pain service (TPS) to improve quality of recovery for patients at risk of CPSP. We hypothesized that a TPS improves the quality of recovery in patients at risk of CPSP.

DESIGN

Single-center, pragmatic, randomized, superiority trial.

SETTING

Tertiary hospital in the Netherlands.

PATIENTS

Assessed for eligibility if ≥18 years of age, undergoing elective surgery, and had an increased risk of developing CPSP. After being stratified for sex, 176 patients were included.

INTERVENTION

Patients were randomized to receive TPS or standard of care (SOC). TPS was a multidisciplinary intervention providing a patient-tailored perioperative pain management plan, throughout all phases of surgery.

MEASUREMENTS

The primary outcome was the difference in quality of recovery on the third postoperative day, measured by the Quality of Recovery (QoR)-15 questionnaire. Secondary outcomes include the between group differences in opioid consumption.

MAIN RESULTS

The primary outcome was available in 169 (96.0%) patients. No difference between groups was found in QoR-15 on the third postoperative day (mean difference 2.0, 95% CI -5.5 to 9.4, p = 0.607). A decrease in opioid usage (compared to baseline) was observed in chronic opioid users, the median [IQR] reduction in total daily oral morphine milligram equivalents (MME) for TPS was -30 [-60, 0] at three and - 29.3 [-65.6, 0] at six months, whereas SOC had a median reduction of 0 [-56, 0] at three, and 0 [-60, 7.5] at six months.

CONCLUSIONS

TPS did not significantly affect short-term quality of recovery but might improve long-term outcomes, such as the incidence of chronic pain, opioid consumption, and functioning in daily life. However, sample size in the present study was too small to provide solid evidence for this positive signal.

Combination of Nanodelivery Systems and Constituents Derived from Novel Foods: A Comprehensive Review

Novel Food is a new category of food, regulated by the European Union Directive No. 2015/2283. This latter norm defines a food as "Novel" if it was not used "for human consumption to a significant degree within the Union before the date of entry into force of that regulation, namely 15 May 1997". Recently, Novel Foods have received increased interest from researchers worldwide. In this sense, the key areas of interest are the discovery of new benefits for human health and the exploitation of these novel sources of materials in new fields of application. An emerging area in the pharmaceutical and medicinal fields is nanotechnology, which deals with the development of new delivery systems at a nanometric scale. In this context, this review aims to summarize the recent advances on the design and characterization of nanodelivery systems based on materials belonging to the Novel Food list, as well as on nanoceutical products formulated for delivering compounds derived from Novel Foods. Additionally, the safety hazard of using nanoparticles in food products, i.e., food supplements, has been discussed in view of the current European regulation, which considers nanomaterials as Novel Foods.

A multidisciplinary transitional pain service to improve pain outcomes following trauma surgery: a preliminary report

OBJECTIVES

Trauma (i.e., musculoskeletal injury from a blunt or penetrating force) can change the trajectory of a person's life. Patients often experience chronic pain, reduced quality of life, long-term opioid therapy, and psychiatric comorbidities after trauma surgery. This case report presents clinical outcomes of four patients who received postsurgical pain care in a transitional pain service (TPS) that provides long-term coordinated multimodal pain care, opioid tapering plans, and psychiatric care.

METHODS

The Personalized Pain Program (PPP) measures prescription opioid use and patient-reported outcomes: pain severity and pain interference (Brief Pain Inventory), pain catastrophizing (Pain Catastrophizing Scale), insomnia severity (Insomnia Severity Index), physical and mental health functioning (SF-12 pre-COVID-19; SF-36 during COVID-19 pandemic) at initial and subsequent clinic visits.

RESULTS

All four patients reduced their postsurgical opioid use with concurrent reductions in pain and improved functioning while receiving postoperative care in the PPP (average length of treatment: 2.8 years). Psychiatric co-treatment addressed the onset or exacerbation of mental health comorbidities following trauma.

CONCLUSIONS

Long-term multidisciplinary pain care may improve post-trauma recovery and reduce risks of long-term opioid therapy and disability. Prospective studies are needed to evaluate the effectiveness of TPSs for patients undergoing trauma surgery.

Low-molecular weight oligosaccharides from gum tragacanth (Astragalus gossypinus) ameliorate nonalcoholic fatty liver disease (NAFLD) in Wistar male rats

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease affecting 25% of the world's population. The effects of oligosaccharides from Gum tragacanth (Astragalus gossypinus) (GT) on oxidative stress, glucose metabolism, and expression of autophagy genes were investigated in induced non-alcoholic fatty liver. Twenty-four male healthy rats were divided into four groups, Control; high-fat diet, high-fat diet + 100 mg GT oligosaccharides/kg body weight, high-fat diet + 200 mg GT oligosaccharides/kg body weight and fed with the trial diets for 70 days. At the end of the experiment, the results indicated that GT oligosaccharides affected the weight gain and liver weight in NAFLD-induced rats. In addition, the results showed that the use of GT oligosaccharides significantly decreased oxidative stress, liver injury, and hyperglycemia (p < .05) and upregulated the expression of autophagy genes in NAFLD-induced rats.

Practical applications

Overall, the results of the current study demonstrated that the use of GT oligosaccharides obtained from Gum tragacanth (Astragalus gossypinus) showed significant antioxidant properties and hypoglycemia in NAFLD induced rats and could be used as a useful nutritional strategy for the prevention and treatment of NAFLD.

Acute and subacute postsurgical pain in women with breast cancer: incidence and associations with biopsychosocial predictors-a secondary analysis of a randomized controlled trial

Introduction

Women who undergo breast cancer surgery risk suffering from postsurgical pain long after their surgery. Still, research on postsurgical pain in the subacute phase has been neglected.

Objective

This study aims to investigate the incidence, intensity, unpleasantness, and presurgical predictors of acute and subacute postsurgical pain after breast cancer surgery.

Methods

The study used an observational design through secondary analyses of the control group in a randomized controlled trial. Data from 102 women undergoing breast cancer surgery were included. Levels of acute and subacute pain intensity and unpleasantness were measured using 100 mm Visual Analogue Scales on the day of surgery and 4 weeks postsurgery. Linear regression analyses were performed to identify presurgical biopsychosocial predictors of acute and subacute postsurgical pain.

Results

Average levels of postsurgical pain intensity and unpleasantness were as follows: 22.7 mm for acute pain intensity, 19.0 mm for acute pain unpleasantness, 10.3 mm for subacute pain intensity, and 11.7 mm for subacute pain unpleasantness. Pain expectancy predicted acute pain intensity (R² = 0.04, p = 0.047) and acute unpleasantness (R² = 0.06, p = 0.02). Perceived social support inversely predicted acute pain unpleasantness (R² = 0.04, p = 0.014).

Conclusion

Mild and moderate acute pain intensity and unpleasantness are common after breast cancer surgery, whereas levels of subacute pain intensity and unpleasantness are low. Pain expectancy predicts acute postsurgical pain intensity and unpleasantness, whereas expected social support inversely predicts acute postsurgical pain unpleasantness.

Chronic pain after surgery and trauma: current situation and future directions

Chronic post-surgical pain (CPSP) stands as a major health issue. The unchanged incidence over the last two decades underlines both the failure of predictive models developed until now and the lack of efficacy of common “preventive” strategies (pharmacotherapy and regional analgesic techniques) applied in current clinical practice. The recognition of CPSP as a disease and the release of a common definition of the condition is an important progress in the field. CPSP predictive scores exist but none has presently demonstrated an impact on patient care. New clinical directions based on the resolution of postoperative pain, a complex and highly dynamic process supported by individual pain trajectories, argue for predictive models and preventive strategies extended to the subacute pain period i.e. after hospital discharge.

Use of regional analgesia to prevent the conversion from acute to chronic pain

PURPOSE OF REVIEW

Chronic post-surgical pain (CPSP) prevalence has not changed over the past decades what questions the efficacy of preventive strategies. Regional analgesia is used to control acute pain, but preventive effect on CPSP remains debated. Failures and future application of regional analgesia to prevent transition from acute to chronic pain will be discussed.

RECENT FINDINGS

After thoracotomy, perioperative regional analgesia does not seem to prevent CPSP. After breast cancer surgery, paravertebral block might prevent CPSP intensity and impact on daily life up to 12 months, particularly in high catastrophizing patients. In knee arthroplasty, perioperative regional analgesia or preoperative genicular nerve neuroablation do not prevent CPSP, although current studies present several bias. The protective role of effective regional analgesia and early pain relief in trauma patients deserves further studies.

SUMMARY

Regional analgesia failure to prevent CPSP development should prompt us to reconsider its perioperative utilization. Patients' stratification, for example high-pain responders, might help to target those who will most benefit of regional analgesia. The impact of regional analgesia on secondary pain-related outcomes such as intensity and neuropathic character despite no difference on CPSP incidence requires more studies. Finally, the preventive effect of regional analgesia targeted interventions on CPSP in patients suffering from severe subacute pain deserves to be assessed.

Identifying Patients Vulnerable to Inadequate Pain Resolution After Cardiac Surgery

Acute postoperative pain (APOP) is often evaluated through granular parameters, though monitoring postoperative pain using trends may better describe pain state. We investigated acute postoperative pain trajectories in cardiac surgical patients to identify subpopulations of pain resolution and elucidate predictors of problematic pain courses. We examined retrospective data from 2810 cardiac surgical patients at a single center. The k-means algorithm for longitudinal data was used to generate clusters of pain trajectories over the first 5 postoperative days. Patient characteristics were examined for association with cluster membership using ordinal and multinomial logistic regression. We identified 3 subgroups of pain resolution after cardiac surgery: 37.7% with good resolution, 44.2% with moderate resolution, and 18.2% exhibiting poor resolution. Type I diabetes (2.04 [1.00-4.16], p = 0.05), preoperative opioid use (1.65 [1.23-2.22], p = 0.001), and illicit drug use (1.89 [1.26-2.83], p = 0.002) elevated risk of membership into worse pain trajectory clusters. Female gender (1.72 [1.30-2.27], p < 0.001), depression (1.60 [1.03-2.50], p = 0.04) and chronic pain (3.28 [1.79-5.99], p < 0.001) increased risk of membership in the worst pain resolution cluster. This study defined 3 APOP resolution subgroups based on pain score trend after cardiac surgery and identified factors that predisposed patients to worse resolution. Patients with moderate or poor pain trajectory consumed more opioids and received them for longer before discharge. Future studies are warranted to determine if altering postoperative pain monitoring and management improve postoperative course of patients at risk of moderate or poor pain resolution.

Effect of acute postsurgical pain trajectories on 30-day and 1-year pain

Untreated pain after surgery leads to poor patient satisfaction, longer hospital length of stay, lower health-related quality of life, and non-compliance with rehabilitation regimens. The aim of this study is to characterize the structure of acute pain trajectories during the postsurgical hospitalization period and quantify their association with pain at 30-days and 1-year after surgery. This cohort study included 2106 adult (≥18 years) surgical patients who consented to participate in the SATISFY-SOS registry (February 1, 2015 to September 30, 2017). Patients were excluded if they did not undergo invasive surgeries, were classified as outpatients, failed to complete follow up assessments at 30-days and 1-year following surgery, had greater than 4-days of inpatient stay, and/or recorded fewer than four pain scores during their acute hospitalization period. The primary exposure was the acute postsurgical pain trajectories identified by a machine learning-based latent class approach using patient-reported pain scores. Clinically meaningful pain (≥3 on a 0–10 scale) at 30-days and 1-year after surgery were the primary and secondary outcomes, respectively. Of the study participants (N = 2106), 59% were female, 91% were non-Hispanic White, and the mean (SD) age was 62 (13) years; 41% of patients underwent orthopedic surgery and 88% received general anesthesia. Four acute pain trajectory clusters were identified. Pain trajectories were significantly associated with clinically meaningful pain at 30-days (p = 0.007), but not at 1-year (p = 0.79) after surgery using covariate-adjusted logistic regression models. Compared to Cluster 1, the other clusters had lower statistically significant odds of having pain at 30-days after surgery (Cluster 2: [OR = 0.67, 95%CI (0.51–0.89)]; Cluster 3:[OR = 0.74, 95%CI (0.56–0.99)]; Cluster 4:[OR = 0.46, 95%CI (0.26–0.82)], all p<0.05). Patients in Cluster 1 had the highest cumulative likelihood of pain and pain intensity during the latter half of their acute hospitalization period (48–96 hours), potentially contributing to the higher odds of pain during the 30-day postsurgical period. Early identification and management of high-risk pain trajectories can help in ascertaining appropriate pain management interventions. Such interventions can mitigate the occurrence of long-term disabilities associated with pain.

Mapping the current state of pediatric surgical pain care across Canada and assessing readiness for change

Background

Preventing pediatric chronic postsurgical pain is a patient, parent/caregiver, health care professional, and policymaker priority. Poorly managed presurgical and acute postsurgical pain are established risk factors for pediatric chronic postsurgical pain. Effective perioperative pain management is essential to prevent the transition from acute to chronic pain after surgery.

Aims

The aim of this study was to identify current pediatric surgical pain management practices and assess health system readiness for change at health care institutions conducting pediatric surgery in Canada.

Methods

An online survey was completed by 85 multidisciplinary health care professionals (nurses, surgeons, anesthesiologists, allied health) from 20 health institutions in Canada regarding institutional pre- and postsurgical pediatric pain care, specialty pain services, and Organizational Readiness for Implementing Change (ORIC).

Results

Of all specialty pain services, acute and chronic/complex pain services were most common, primarily with physician and nursing involvement. Alignment to recommended practices for pediatric pre- and postsurgical pain care varied (38.1%–79.8% reported “yes, for every child”), with tertiary/quaternary children’s hospitals reporting less alignment than other institutions (community/regional or rehabilitation hospitals, community treatment centers). No significant differences were reported between health care institutions serving pediatric populations only versus those also serving adults. Health care professional experience/practice was the most reported strength in pediatric surgical pain care, with inconsistent standard of care the most common gap. Participants “somewhat agreed” that their institutions were committed and capable of change in pediatric surgical pain care.

Conclusions

There is a continued need to improve pediatric pain care during the perioperative period at Canadian health care institutions to effectively prevent the development of pediatric postsurgical pain.

Patient perceptive focus on recovery: An exploratory study on follow-up after major emergency abdominal surgery

BACKGROUND

Optimal recovery can be defined as the adequate in-hospital length of stay with minimal postoperative complications and readmissions. The quality of recovery beyond the immediate postoperative period after major emergency abdominal surgery is yet to be fully described. We hypothesized that long-term measures of overall recovery were affected after surgery. The study aimed to investigate patient-focused recovery-related parameters 1 year after major emergency abdominal surgery.

METHOD

This is a prospective study including patients undergoing major emergency abdominal surgery at a Danish secondary referral center. Three questionnaires were answered regarding the recovery following the procedure; Activities Assessment Scale (AAS); Quality of Recovery-15 (QoR-15), and Self-complete Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS). All questionnaires were answered at postoperative days (PODs) 14, 30, 90, and 365.

RESULTS

Eighty-two patients were included, and 68 were available for follow-up until 1 year after surgery. The response rates differed between the follow-up time points, with a response rate of 85% (n = 59) at POD30 and 50% (n = 36) at POD365. A decrease in the level of physical function following surgery was observed in 60% of the patients at POD14, which improved to 36% at POD365. Twenty-four patients (48%) reported postoperative pain at POD14, which declined to 9 (26%) at POD365. The maximum overall recovery was reached at POD30, which remained stable throughout the study period.

CONCLUSION

One in three patients reported physical functional impairment, and one in four patients reported pain 1 year after their surgical procedure.

Using a postoperative pain trajectory to predict pain at 1 year after total knee arthroplasty

BACKGROUND

The pain trajectory is an early detection/prediction method for chronic postsurgical pain (CPSP). It is unclear whether a pain trajectory can predict CPSP in patients who have undergone a total knee arthroplasty (TKA). Here we investigated (1) whether CPSP can be predicted in TKA patients, and (2) the values that can be used to predict CPSP.

METHODS

We studied 211 postoperative TKA patients. We calculated the pain trajectory (pain curve slope and intercept) using the patients' self-reported pain intensity values at 1, 3, 5, and 7 days post-TKA. Using structural equation modeling (SEM), we performed a multiple regression analysis to investigate appropriate prediction models for the pain trajectory. Classification and regression tree (CHAID) methodology was used to calculate values to predict CPSP by a decision tree model. CPSP (dependent variable) was defined as >30 mm on a visual analog scale for pain intensity at 1 year post-TKA. The predictor variables were pain curve slope, intercept, age, sex, body mass index, and preoperative pain intensity.

RESULTS

The pain trajectory was the best fit among the models to predict pain intensity at 1 year post-TKA. When the pain curve slope (pain trajectory) was greater than 2.8, the probability of CPSP at 1 year post-TKA was 33.3%.

CONCLUSION

Our results suggest that the pain trajectory could be applied to post-TKA patients and used to calculate clinical values to predict CPSP. Our findings also indicate the possibility that patients with a positive pain curve slope in the first postoperative week may need early intervention to avoid CPSP.

Study protocol for the TRUSt trial: a pragmatic randomised controlled trial comparing the standard of care with a transitional pain service for patients at risk of chronic postsurgical pain undergoing surgery

INTRODUCTION

Patients with either surgery-related or patient-related risk factors are at an increased risk of acute and chronic postsurgical pain (CPSP) and long-term opioid use. To improve recovery, prevent CPSP and decrease opioid use, we need to identify these patients before surgery and provide a multidisciplinary pain management strategy throughout hospital admission and follow-up in the postdischarge period. We hypothesise that a multidisciplinary transitional pain service (TPS) improves quality of recovery and reduce the incidence of CPSP and opioid consumption.

METHODS AND ANALYSIS

We aim to investigate the effectiveness of implementation of a TPS for patients at risk of developing CPSP. The trial design is a pragmatic, open-label, randomised controlled trial (RCT). After stratification for sex, patients are randomly assigned to the TPS or standard of care (SOC) group. Our primary outcome is the quality of recovery, measured at the morning of the third postoperative day, employing the quality of recovery (QoR)-15 questionnaire. Secondary outcomes are the incidence of CPSP, opioid consumption and patient-reported outcome measures at 3 and 6 months postoperatively. We need to enrol 176 patients to detect a minimal clinical important difference of 8 points on the QoR-15 score.

ETHICS AND DISSEMINATION

Ethics approval was obtained by the accredited medical research ethics committee of the Academic Medical Center in Amsterdam (2020_211) on 15 October 2020. Protocol version 3.2 was approved on 25 January 2020. The trial is registered with the Netherlands Trial Register, NL9115. The results will be disseminated by open access publication in a peer-reviewed journal.Trial registration number NL9115.

Identification of preoperative predictors for acute postsurgical pain and for pain at three months after surgery: a prospective observational study

Identifying patients at risk is the start of adequate perioperative pain management. We aimed to identify preoperative predictors for acute postsurgical pain (APSP) and for pain at 3 months after surgery to develop prediction models. In a prospective observational study, we collected preoperative predictors and the movement-evoked numerical rating scale (NRS-MEP) of postoperative pain at day 1, 2, 3, 7, week 1, 6 and 3 months after surgery from patients with a range of surgical procedures. Regression analyses of data of 2258 surgical in- and outpatients showed that independent predictors for APSP using the mean NRS-MEP over the first three days after surgery were hospital admittance, female sex, higher preoperative pain, younger age, pain catastrophizing, anxiety, higher score on functional disability, highest categories of expected pain, medical specialty, unknown wound size, and wound size > 10 cm compared to wound size ≤ 10 cm (RMSE = 2.11). For pain at three months, the only predictors were preoperative pain and a higher score on functional disability (RMSE = 1.69). Adding pain trajectories improved the prediction of pain at three months (RMSE = 1.37). Our clinically applicable prediction models can be used preoperatively to identify patients at risk, as well as in the direct postoperative period.

Temporal Association of Pain Catastrophizing and Pain Severity Across the Perioperative Period: A Cross-Lagged Panel Analysis After Total Knee Arthroplasty

OBJECTIVE

Although numerous studies show that preoperative pain catastrophizing is a risk factor for pain after total knee arthroplasty (TKA), little is known about the temporal course of the association between perioperative pain catastrophizing and pain severity. The present study investigated temporal changes and their dynamic associations between pain catastrophizing and pain severity before and after TKA.

DESIGN

A secondary data analysis of a larger observational parent study featuring prospective repeated measurement over 12 months.

SETTING

Dual-site academic hospital.

SUBJECTS

A total of 245 individuals who underwent TKA.

METHODS

Participants completed pain catastrophizing and pain severity questionnaires at baseline, 6 weeks, and 3, 6, and 12 months after TKA. Cross-lagged panel analysis was conducted with structural equation modeling including age, sex, race, baseline anxiety, and depressive symptoms as covariates.

RESULTS

Reduction in pain catastrophizing from baseline to 6 weeks after TKA was associated with lower pain severity at 3 months after TKA (standardized β = 0.14; SE = 0.07, P = 0.046), while reduction in pain severity at 6 weeks after TKA was not associated with pain catastrophizing at 3 months after TKA (P = 0.905). In the chronic postsurgical period (>3 months), pain catastrophizing at 6 months after TKA predicted pain severity at 12 months after TKA (β = 0.23, P = 0.009) with controlling for auto-correlation and covariates, but not vice versa.

CONCLUSIONS

We provide evidence that changes in pain catastrophizing from baseline to 6 weeks after TKA are associated with subsequent pain severity. Future studies are warranted to determine whether targeting pain catastrophizing during the perioperative period may improve clinical outcomes for individuals undergoing TKA.

The opioid epidemic from the acute care hospital front line

Prescription opioid use has risen steeply for over two decades, driven primarily by advocacy for better management of chronic non-cancer pain, but also by poor opioid stewardship in the management of acute pain. Inappropriate prescribing, among other things, contributed to the opioid 'epidemic' and striking increases in patient harm. It has also seen a greater proportion of opioid-tolerant patients presenting to acute care hospitals. Effective and safe management of acute pain in opioid-tolerant patients can be challenging, with higher risks of opioid-induced ventilatory impairment and persistent post-discharge opioid use compared with opioid-naive patients. There are also increased risks of some less well known adverse postoperative outcomes including infection, earlier revision rates after major joint arthroplasty and spinal fusion, longer hospital stays, higher re-admission rates and increased healthcare costs. Increasingly, opioid-free/opioid-sparing techniques have been advocated as ways to reduce patient harm. However, good evidence for these remains lacking and opioids will continue to play an important role in the management of acute pain in many patients.Better opioid stewardship with consideration of preoperative opioid weaning in some patients, assessment of patient function rather than relying on pain scores alone to assess adequacy of analgesia, prescription of immediate release opioids only and evidence-based use of analgesic adjuvants are important. Post-discharge opioid prescribing should be contingent on an assessment of patient risk, with short-term only use of opioids. In partnership with pharmacists, nursing staff, other medical specialists, general practitioners and patients, anaesthetists remain ideally positioned to be involved in opioid stewardship in the acute care setting.

Multimodal spatio-temporal deep learning approach for neonatal postoperative pain assessment

The current practice for assessing neonatal postoperative pain relies on bedside caregivers. This practice is subjective, inconsistent, slow, and discontinuous. To develop a reliable medical interpretation, several automated approaches have been proposed to enhance the current practice. These approaches are unimodal and focus mainly on assessing neonatal procedural (acute) pain. As pain is a multimodal emotion that is often expressed through multiple modalities, the multimodal assessment of pain is necessary especially in case of postoperative (acute prolonged) pain. Additionally, spatio-temporal analysis is more stable over time and has been proven to be highly effective at minimizing misclassification errors. In this paper, we present a novel multimodal spatio-temporal approach that integrates visual and vocal signals and uses them for assessing neonatal postoperative pain. We conduct comprehensive experiments to investigate the effectiveness of the proposed approach. We compare the performance of the multimodal and unimodal postoperative pain assessment, and measure the impact of temporal information integration. The experimental results, on a real-world dataset, show that the proposed multimodal spatio-temporal approach achieves the highest AUC (0.87) and accuracy (79%), which are on average 6.67% and 6.33% higher than unimodal approaches. The results also show that the integration of temporal information markedly improves the performance as compared to the non-temporal approach as it captures changes in the pain dynamic. These results demonstrate that the proposed approach can be used as a viable alternative to manual assessment, which would tread a path toward fully automated pain monitoring in clinical settings, point-of-care testing, and homes.

Effects of Chinese wolfberry and Astragalus extract on the antioxidant capacity of Tibetan pig liver

The objective of this study is to determine the effect of Chinese wolfberry (Lycium barbarum) and Astragalus (Astragalus membranaceus) extract (WAE) on the antioxidant capacity of Tibetan pig liver, and discussed the regulatory effect of WAE on the liver antioxidant mechanism. Twelve healthy 120-day-old Tibetan black pigs (35±2 kg) were divided randomly into two groups. The WAE group was fed a basal diet supplemented with 1% WAE for 90 days. The control group was fed the same diet, but without the WAE. We found that liver superoxide dismutase 1 (SOD1) activity (P<0.05), total antioxidative capacity (T-AOC) (P<0.05), and catalase (CAT) activity (P<0.01) significantly increased in the WAE group compared with the control group; malondialdehyde (MDA) content decreased, but this was not significant (P >0.05). Transcriptome sequencing analysis detected 106 differentially expressed genes (DEGs) related to oxidative stress. GO enrichment analysis showed these DEGs were involved in the positive regulation of reactive oxygen metabolism and biosynthesis, process regulation, and regulation of the oxidative stress response. KEGG Pathway enrichment analysis showed they were enriched in the PI3K-Akt, AMPK, Rap1, and peroxisome signaling pathways. The expression levels of key peroxisome biosynthesis genes (e.g., PEX3 and PEX11B) and key antioxidant genes (e.g., CAT and SOD1) were significantly higher in the WAE group than in the control group. The PRDX1 and PRDX5 content also was significantly higher in the WAE group. This study showed that the WAE regulated the antioxidant and anti-stress ability of Tibetan pig liver through a "peroxisome antioxidant-oxidant stress" signaling pathway.

[Prediction and prevention of chronic postoperative pain]

Chronic postoperative pain has been identified as a major medical and socioeconomic problem. A prevention of the chronification processes is potentially possible and preventive treatment could start early (e.g. preoperatively). So far, however, evidence for the effectiveness of preventive strategies is basically low. Important reasons for this dilemma are the lack of appropriate risk assessment as well as effective and mechanism-based preventive (procedure-sepcific) strategies for the chronification process, a lack of stratification of treatment approaches and a so far barely investigated combination of various treatment approaches. In this review article recent findings on the appropriate identification of patients at risk for developing postoperative chronic pain are presented, predictive models for the valid estimation of the individual risk of patients are assessed and studies on pharmaceutical and regional analgesia techniques influencing the pain chronification process are discussed. As a chronification process is, however, extremely complex and dynamic and also necessitates adaptation of the prevention during the course of the process, only combinations of treatment, interdisciplinary and if necessary even longer term approaches might be successful. Future studies are needed to address with which preventive treatment strategies and in which patients chronic pain after surgery can effectively be prevented.

Multidisciplinary Transitional Pain Service for the Veteran Population

BACKGROUND

For patients with existing chronic opioid use or a history of substance use disorder, often little presurgical planning or postsurgical coordination of care among surgeons, primary care providers, or addiction care providers occurs.

METHODS

In 2018, we developed the Transitional Pain Service (TPS) to identify at-risk patients as soon as they were indicated for surgery, to allow time for evaluation, education, and developing an individualized pain plan, and opioid taper prior to surgery if indicated. An electronic dashboard registry of surgical episodes provided data to TPS providers and included baseline history, morphine equivalent daily dose, and patient-reported pain outcomes, using measures from the Patient-Reported Outcome Measurement System for pain intensity, pain interference, and physical function, and a pain-catastrophizing scale score.

RESULTS

Two-hundred thirteen patients were enrolled between January and December 2018. Nearly all (99%) patients had ≥ 1 successful follow-up within 14 days after discharge; 96% had ≥ 1 follow-up between 14 and 30 days after surgery; and 72% had completed personal follow-up 90 days after discharge.

CONCLUSIONS

In 2018 the overall use of opioids after orthopedic surgery decreased by > 40% from the previous year. Despite this more restricted use of opioids, pain interference and physical function scores indicated that surgical patients do not seem to experience increased pain or reduced physical function.

Multidisciplinary care for opioid dose reduction in patients with chronic non-cancer pain: A systematic realist review

CONTEXT

Opioid related deaths are at epidemic levels in many developed nations globally. Concerns about the contribution of prescribed opioids, and particularly high-dose opioids, continue to mount as do initiatives to reduce prescribing. Evidence around opioid tapering, which can be challenging and potentially hazardous, is not well developed. A recent national guideline has recognized this and recommended referral to multidisciplinary care for challenging cases of opioid tapering. However, multidisciplinary care for opioid tapering is not well understood or defined.

OBJECTIVE

Identify the existing literature on any multidisciplinary care programs that evaluate impact on opioid use, synthesize how these programs work and clarify whom they benefit.

STUDY DESIGN

Systematic rapid realist review.

DATASET

Bibliographic databases (MEDLINE, EMBASE, CINAHL, PsycINFO, Cochrane Library), grey literature, reference hand search and formal expert consultation.

RESULTS

95 studies were identified. 75% of the programs were from the United States and the majority (n = 62) were published after 2000. A minority (n = 23) of programs reported on >12 month opioid use outcomes. There were three necessary but insufficient mechanisms common to all programs: pain relief, behavior change and active medication management. Programs that did not include a combination of all three mechanisms did not result in opioid dose reductions. A concerning 20-40% of subjects resumed opioid use within one year of program completion.

CONCLUSIONS

Providing alternative analgesia is insufficient for reducing opioid doses. Even high quality primary care multidisciplinary care programs do not reduce prescribed opioid use unless there is active medication management accomplished by changing the primary opioid prescriber. Rates of return to use of opioids from these programs are very concerning in the current context of a highly potent and lethal street drug supply. This contextual factor may be powerful enough to undermine the modest benefits of opioid dose reduction via multidisciplinary care.

Predicting poor postoperative acute pain outcome in adults: an international, multicentre database analysis of risk factors in 50,005 patients

Supplemental Digital Content is Available in the Text.

Eight risk factors were identified in a large international database. Patients with 3 or more risk factors are at higher risk for poor pain outcome.

Background:

The aim of this study was to determine simple risk factors for severe pain intensity (≥7 points on a numeric rating scale [NRS]), to analyse their relation to other patient-reported outcome measures and to develop a simple prediction model.

Methods:

We used data from 50,005 patients from the PAIN-OUT project. Within a first data set (n = 33,667), relevant risk factors were identified by logistic binary regression analysis, assessed for additional patient-reported outcome measures beyond pain intensity and summed up for developing a simple risk score. Finally, sum of factors was plotted against postoperative pain outcomes within a validation data set (n = 16,338).

Results:

Odds ratios (OR) for the following risk factors were identified: younger age (<54 years, OR: 1.277), preoperative chronic pain at the site of surgery (OR: 1.195), female sex (OR: 1.433), duration of surgery (>90 minutes, OR: 1.308), preoperative opioid intake (OR: 1.250), feeling anxious (OR: 1.239) and feeling helpless due to pain (OR: 1.198), and the country of the recruiting centre (OR: 1.919). Patients with ≥3 risk factors had more severe pain intensity scores, spent a longer time in severe pain, and wished to have received more pain treatment (P < 0.001). A simple risk score was created with 4 risk factors showing a moderate prediction level.

Conclusions:

Patients with ≥3 risk factors are at higher risk for poor postoperative acute pain outcome after surgery. Future studies using this score might show that preventive strategies might decrease pain intensity, pain-related postoperative dysfunction, and the development of chronic pain.

A descriptive study of pain treatment and its follow-up in primary care of elderly patients after orthopaedic care

Background

Pain treatment post orthopaedic care in the elderly is complicated and requires careful follow-up. Current guidelines state all patients prescribed opioids should have a plan for gradual reduction, with the treatment progressively reduced and ended if any pain remains after more than three months. How this works in primary care remains to be explored.

The aim was to describe pain treatment and its follow-up in primary care of elderly patients after orthopaedic care.

Methods

In this descriptive study, medical case histories were collected for patients ≥ 75 years, which were enrolled at two rural primary care units in southern Sweden, and were discharged from orthopaedic care. Pain medication follow-up plans were noted, as well as current pain medication at discharge as well as two, six and twelve weeks later.

Results

We included a total of 49 community-dwelling patients with medication aid from nurses in municipality care and nursing home residents, ≥ 75 years, discharged from orthopaedic care. The proportion of patients prescribed paracetamol increased from 28/49 (57%) prior to admission, to 38/44 (82%) after 12 weeks. The proportion of patients prescribed opioids increased from 5/49 (10%) to 18/44 (41%). Primary care pain medication follow-up plans were noted for 16/49 patients (33%).

Conclusions

Many patients still used pain medication 12 weeks after discharge, and follow-up plans were quite uncommon, which may reflect upon lacking follow-up of these patients in primary care.

Pain therapy to reduce perioperative complications

The incidence rates of adverse events secondary to any operation are a well-known problem in any surgical field. One outstanding example of such adverse events is postoperative pain. Thus, the incidence of acute postoperative pain following any surgical procedure and its treatment are central issues for every surgeon. In the times of Enhanced Recovery After Surgery (ERAS) programs, acute pain therapy became an increasingly well investigated and accepted aspect in almost all surgical subspecialties. However, if it comes to the reduction of postoperative complications, in the actual context of postoperative pain, surgeons tend to focus on the operative process rather than on the perioperative procedures. Undoubtedly, postoperative pain became an important factor with regard to the quality of surgical care: both, the extent and the quality of the surgical procedure and the extent and the quality of the analgesic technique are decisive issues for a successful pain management. There is growing evidence that supports the role of acute pain therapy in reducing postoperative morbidity, and it has been demonstrated that high pain scores postoperatively may contribute to a complicated postoperative course. This overview comprises the current knowledge on the role of acute pain therapy with regard to the occurrence of postoperative complications. Most of the knowledge is derived from studies that primarily focus on the type and quality of postoperative pain therapy in relation to specific surgical procedures and only secondary on complications. As far as existent, data that report on the recovery period after surgery, on the rehabilitation status, on perioperative morbidity, on the development of chronic pain after surgery, and on possible solutions of the latter problem with the institution of transitional pain services will be presented.

Chronic postsurgical pain: From risk factor identification to multidisciplinary management at the Toronto General Hospital Transitional Pain Service

Background: Chronic postsurgical pain is a highly prevalent public health problem associated with substantial emotional, social, and economic costs. Aims: (1) To review the major risk factors for chronic postsurgical pain (CPSP); (2) to describe the implementation of the Transitional Pain Service (TPS) at the Toronto General Hospital, a multiprofessional, multimodal preventive approach to CPSP involving intensive, perioperative psychological, physical, and pharmacological management aimed at preventing and treating the factors that increase the risk of CPSP and related disability; and (3) to present recent empirical evidence for the efficacy of the TPS. Methods: The Toronto General Hospital TPS was specifically developed to target patients at high risk of developing CPSP. The major known risk factors for CPSP are perioperative pain, opioid use, and negative affect, including depression, anxiety, pain catastrophizing, and posttraumatic stress disorder-like symptoms. At-risk patients are identified early and provided comprehensive care by a multidisciplinary team consisting of pain physicians, advanced practice nurses, psychologists, and physical therapists. Results: Preliminary results from two nonrandomized, clinical practice-based trials indicate that TPS treatment is associated with improvements in pain, pain interference, pain catastrophizing, symptoms of anxiety and depression, and opioid use. Almost half of opioid-naïve patients and one in four opioid-experienced patients were opioid free by the 6-month point. Conclusions: These promising results suggest that the TPS benefits patients at risk of CPSP. A multicenter randomized controlled trial of the TPS in several Ontario hospitals is currently underway.

The prescription opioid crisis: role of the anaesthesiologist in reducing opioid use and misuse

Reports of strategies to prevent and treat the opioid epidemic are growing. Significant attention has been paid to the benefits of opioid addiction research, clinical prescribing, and public policy initiatives in curbing the epidemic. However, the role of the anaesthesiologist in minimising opioid use and misuse remains underexplored. For many patients with an opioid use disorder, the perioperative period represents the source of initial exposure. As perioperative physicians, anaesthesiologists are in the unique position to manage pain effectively while simultaneously decreasing opioid consumption. Multiple opportunities exist for anaesthesiologists to minimise opioid exposure and prevent subsequent persistent opioid use. We present a global strategy for decreasing perioperative opioid use and misuse among surgical patients. A historical perspective of the opioid epidemic is presented, together with an analysis of opioid supply and demand forces. We then present specific temporal strategies for opioid use reduction in the perioperative period. We emphasise the importance of preoperative identification of patients at risk for long-term opioid use and misuse, review the evidence supporting the opioid sparing capacity of individual multimodal analgesic agents, and discuss the benefits of regional anaesthesia for minimising opioid consumption. We describe postoperative and post-discharge tools, including effective multimodal analgesia and the role of a transitional pain service. Finally, we offer general institutional strategies that can be led by anaesthesiologists, identify gaps in knowledge, and offer directions for future research.

Addressing the Opioid Crisis One Surgical Patient at a Time: Outcomes of a Novel Perioperative Pain Program

Opioid prescriptions in the surgical setting have been implicated as contributors to the opioid epidemic. The authors hypothesized that a multidisciplinary approach to perioperative pain management for patients on chronic opioid therapy could decrease postoperative opioid requirements while reducing postoperative pain scores and improving functional outcomes. Therefore, a Perioperative Pain Program (PPP) for chronic opioid users was implemented. This study presents outcomes from the first 9 months of the PPP. Sixty-one patients met the inclusion criteria. Opioid consumption in morphine milligram equivalent (MME) was calculated and physical and health status of patients was assessed with the Brief Pain Inventory, Short-Form McGill Pain Questionnaire, and Short Form-12. Preliminary results showed significant reduction in MME, improved pain scores, and improved function for surgical patients on chronic opioids. PPP effectively reduced opioid usage without negatively influencing patient-reported outcomes, such as physical pain score assessment and health-related quality of life.

Transition from acute to chronic pain after surgery

Over the past decade there has been an increasing reliance on strong opioids to treat acute and chronic pain, which has been associated with a rising epidemic of prescription opioid misuse, abuse, and overdose-related deaths. Deaths from prescription opioids have more than quadrupled in the USA since 1999, and this pattern is now occurring globally. Inappropriate opioid prescribing after surgery, particularly after discharge, is a major cause of this problem. Chronic postsurgical pain, occurring in approximately 10% of patients who have surgery, typically begins as acute postoperative pain that is difficult to control, but soon transitions into a persistent pain condition with neuropathic features that are unresponsive to opioids. Research into how and why this transition occurs has led to a stronger appreciation of opioid-induced hyperalgesia, use of more effective and safer opioid-sparing analgesic regimens, and non-pharmacological interventions for pain management. This Series provides an overview of the epidemiology and societal effect, basic science, and current recommendations for managing persistent postsurgical pain. We discuss the advances in the prevention of this transitional pain state, with the aim to promote safer analgesic regimens to better manage patients with acute and chronic pain.

Prevention and Treatment of Chronic Postsurgical Pain: A Narrative Review

Chronic postsurgical pain affects between 5 and 75% of patients, often with an adverse impact on quality of life. While the transition of acute to chronic pain is a complex process-involving multiple mechanisms at different levels-the current strategies for prevention have primarily been restricted to perioperative pharmacological interventions. In the present paper, we first present an up-to-date narrative literature review of these interventions. In the second section, we develop several ways by which we could overcome the limitations of the current approaches and enhance the outcome of our surgical patients, including the better identification of individual risk factors, tailoring treatment to individual patients, and improved acute and subacute pain evaluation and management. The third and final section covers the treatment of established CPSP. Given that evidence for the current therapeutic options is limited, we need high-quality trials studying multimodal interventions matched to pain characteristics.

Antioxidant, immunomodulatory, oxidative stress inhibitory and iron supplementation effect of Astragalus membranaceus polysaccharide-iron (III) complex on iron-deficiency anemia mouse model

As iron supplement, the antioxidant activities of APS-iron (III) complex were comprehensively evaluated by 5-axe cobweb charts, which indicated the APS-iron (III) complex had a certain antioxidant activity and been weaker than that of APS. The results of immunological activity experiments indicated the stimulation index increased with APS-iron (III) complex concentration increase. When the concentration of the APS-iron (III) complex was 50 μg/mL, the lymphocytes proliferation increased by 35.7% compared with APS. APS-iron (III) complex also had better complement fixing activity than APS, 0.589 mg/mL of which achieved 50% complement fixing activities. Through the iron supplement experiments on iron-deficiency anemia mouse model, we found the APS-iron (III) complex faster increased hemoglobin concentration, SOD, CAT and faster decreased MDA to the normal level than Niferex and ferrous sulfate. Histological results revealed that the tissue sections were clear without obvious pathological changes and bone marrow had most hematopoietic cells from APS-iron (III) complex rat group, which also proved the APS-iron (III) complex had no significant side effects. Therefore, APS-iron (III) complex may be developed as a multifunctional iron supplement for clinical application.

Factors Associated With Acute Pain Estimation, Postoperative Pain Resolution, Opioid Cessation, and Recovery: Secondary Analysis of a Randomized Clinical Trial

Importance

Acute postoperative pain is associated with the development of persistent postsurgical pain, but it is unclear which aspect is most estimable.

Objective

To identify patient clusters based on acute pain trajectories, preoperative psychosocial characteristics associated with the high-risk cluster, and the best acute pain predictor of remote outcomes.

Design, Setting, and Participants

A secondary analysis of the Stanford Accelerated Recovery Trial randomized, double-blind clinical trial was conducted at a single-center, tertiary, referral teaching hospital. A total of 422 participants scheduled for thoracotomy, video-assisted thoracoscopic surgery, total hip replacement, total knee replacement, mastectomy, breast lumpectomy, hand surgery, carpal tunnel surgery, knee arthroscopy, shoulder arthroplasty, or shoulder arthroscopy were enrolled between May 25, 2010, and July 25, 2014. Data analysis was performed from January 1 to August 1, 2018.

Interventions

Patients were randomized to receive gabapentin (1200 mg, preoperatively, and 600 mg, 3 times a day postoperatively) or active placebo (lorazepam, 0.5 mg preoperatively, inactive placebo postoperatively) for 72 hours.

Main Outcomes and Measures

A modified Brief Pain Inventory prospectively captured 3 surgical site pain outcomes: average pain and worst pain intensity over the past 24 hours, and current pain intensity. Within each category, acute pain trajectories (first 10 postoperative pain scores) were compared using a k-means clustering algorithm. Fifteen descriptors of acute pain were compared as predictors of remote postoperative pain resolution, opioid cessation, and full recovery.

Results

Of the 422 patients enrolled, 371 patients (≤10% missing pain scores) were included in the analysis. Of these, 146 (39.4%) were men; mean (SD) age was 56.67 (11.70) years. Two clusters were identified within each trajectory category. The high pain cluster of the average pain trajectory significantly predicted prolonged pain (hazard ratio [HR], 0.63; 95% CI, 0.50-0.80; P < .001) and delayed opioid cessation (HR, 0.52; 95% CI, 0.41-0.67; P < .001) but was not a predictor of time to recovery in Cox proportional hazards regression (HR, 0.89; 95% CI, 0.69-1.14; P = .89). Preoperative risk factors for categorization to the high average pain cluster included female sex (adjusted relative risk [ARR], 1.36; 95% CI, 1.08-1.70; P = .008), elevated preoperative pain (ARR, 1.11; 95% CI, 1.07-1.15; P < .001), a history of alcohol or drug abuse treatment (ARR, 1.90; 95% CI, 1.42-2.53; P < .001), and receiving active placebo (ARR, 1.27; 95% CI, 1.03-1.56; P = .03). Worst pain reported on postoperative day 10 was the best predictor of time to pain resolution (HR, 0.83; 95% CI, 0.78-0.87; P < .001), opioid cessation (HR, 0.84; 95% CI, 0.80-0.89; P < .001), and complete surgical recovery (HR, 0.91; 95% CI, 0.86-0.96; P < .001).

Conclusions and Relevance

This study has shown a possible uniform predictor of remote postoperative pain, opioid use, and recovery that can be easily assessed. Future work is needed to replicate these findings.

Trial Registration

ClinicalTrials.gov Identifier: NCT01067144.

The Effect of the Treatment at a Pain Clinic on the Patients' Assessment of Their Pain Intensity and the Incidence of Mental Disorders in the form of Anxiety, Depression, and Aggression

The aim of the study was to analyze the effect of the treatment given to patients in a pain clinic on their assessment of pain intensity and the incidence of emotional disturbances in the form of anxiety, depression, and aggression. The study was conducted from January 2014 to April 2018 among patients under the care of two Warsaw pain clinics. The study tools were the Hospital Anxiety and Depression Scale-Modified Version (HADS-M) and the Numerical Rating Scale (NRS). The project enrolled 325 patients, with women comprising 60.62% of patients, and the age bracked of 65⁻79 years comprising 39.38% of patient. The major reasons for attending the pain clinic were osteoarticular pain (44.92%) and neuropathic pain (42.77%). The therapy applied lowered the patients' pain intensity (4.98 vs. 3.83), anxiety (8.71 vs. 8.12), aggression (3.30 vs. 3.08), and the overall HADS-M score (18.93 vs. 17.90), which shows that the treatment of both the pain symptoms and the associated emotional disturbances in the form of anxiety and aggression was effective. Sex is a factor affecting pain intensity. The level of mental disorders was influenced by the sex and age of the patients and how long they had been treated in the pain clinics.

Postpartum chronic pain

Postpartum chronic pain is a clinical reality which affects 6.1% to 11.5% of women after delivery and affects their recovery. The large range of incidence observed in the literature relies on criteria used to define chronic postpartum pain. The features depend on the type of delivery. Cesarean delivery which rate is increasing worldwide seems currently associated with lower risk of chronic postpartum pain, specifically chronic pelvic pain. Further chronic scar pain which often involves a neuropathic component is often of mild intensity. In opposite, after vaginal delivery, chronic pelvic pain and perineal pain have an important negative impact on women's mood and quality of life. As for any chronic pain, individual risk factors account more than degree of tissue trauma. From actual reports in the field, better pain education of both women and health care providers might help to reduce the problem.

Establishing an Acute Pain Service in Private Practice and Updates on Regional Anesthesia Billing

Acute pain management is an expanding perioperative specialty and there is a renewed focus on implementing and developing an acute pain service (APS) in nonacademic hospitals (ie, "private practice"). An anesthesiologist-led APS can improve patient care by decreasing perioperative morbidity and potentially reducing the risk of chronic postsurgical pain syndromes. Elements of a successful APS include multidisciplinary collaboration to develop perioperative pain protocols, education of health care providers and patients, and regular evaluation of patient safety and quality of care metrics. Standardization of regional anesthesia procedures and billing practices can promote consistent outcomes and efficiency.