Pain measures and cut-offs - ‘no worse than mild pain’ as a simple, universal outcome

Who develops chronic pain after an acute lower limb injury? A longitudinal study of children and adolescents

ABSTRACT

Prevention of chronic pain is a major challenge in this area of clinical practice. To do this, we must be able to understand who is most at risk of developing chronic pain after an injury. In this study, we aimed to identify risk factors of chronic pain onset, disability, and pain interference after a lower limb musculoskeletal injury in children and adolescents between 8 to 16 years of age. We assessed biopsychosocial factors including age, sex, pubertal status, anxiety, depression, fear of pain, pain worry, adverse life events, and sleep in children. We also assessed risk factors in parents including parent anxiety, depression, parent pain catastrophising, and protective behaviours. Logistic and hierarchical linear regressions identified risk factors assessed immediately postinjury for outcomes assessed at 3 months postinjury. Fourteen percent (17/118 children) reported chronic pain 3 months after injury. There were significant between-group differences in children with and without chronic pain at baseline. Children with chronic pain reported higher pain intensity, disability, pain interference, child depression, fear of pain, and catastrophic thinking about their pain. Regressions showed child depression and fear of pain at baseline independently predicted chronic pain onset at 3 months, parent protectiveness predicted child pain interference at 3 months, and child depression, poor sleep, parent anxiety and pain catastrophising predicted disability. Most children recover after a lower limb injury, but a minority develop chronic pain predicted by important psychosocial risk factors, which could be addressed to prevent the onset of treatment-resistant chronic pain and disability.

Clinical and Adverse Outcomes Associated With Concomitant Use of CYP2D6-Metabolized Opioids With Antidepressants in Older Nursing Home Residents : A Target Trial Emulation Study

BACKGROUND

Limited evidence exists on the safety of pharmacokinetic interactions of cytochrome P450 (CYP) 2D6 (CYP2D6)-metabolized opioids with antidepressants among older nursing home (NH) residents.

OBJECTIVE

To investigate the associations of concomitant use of CYP2D6-metabolized opioids and antidepressants with clinical outcomes and opioid-related adverse events (ORAEs).

DESIGN

Retrospective cohort study using a target trial emulation framework.

SETTING

100% Medicare NH sample linked to Minimum Data Set (MDS) from 2010 to 2021.

PARTICIPANTS

Long-term residents aged 65 years and older receiving CYP2D6-metabolized opioids with a disease indication for antidepressant use.

INTERVENTION

Initiating CYP2D6-inhibiting versus CYP2D6-neutral antidepressants that overlapped with use of CYP2D6-metabolized opioids for 1 day or more.

MEASUREMENTS

Clinical outcomes were worsening pain, physical function, and depression from baseline to quarterly MDS assessments and were analyzed using modified Poisson regression models. The ORAE outcomes included counts of pain-related hospitalizations and emergency department (ED) visits, opioid use disorder (OUD), and opioid overdose and were analyzed with negative binomial or Poisson regression models. All models were adjusted for baseline covariates via inverse probability of treatment weighting.

RESULTS

Among 29 435 identified residents, use of CYP2D6-metabolized opioids concomitantly with CYP2D6-inhibiting (vs. CYP2D6-neutral) antidepressants was associated with a higher adjusted rate ratio of worsening pain (1.13 [95% CI, 1.09 to 1.17]) and higher adjusted incidence rate ratios of pain-related hospitalization (1.37 [CI, 1.19 to 1.59]), pain-related ED visit (1.49 [CI, 1.24 to 1.80]), and OUD (1.93 [CI, 1.37 to 2.73]), with no difference in physical function, depression, and opioid overdose.

LIMITATION

Findings are generalizable to NH populations only.

CONCLUSION

Use of CYP2D6-metabolized opioids concomitantly with CYP2D6-inhibiting (vs. CYP2D6-neutral) antidepressants was associated with worsening pain and increased risk for most assessed ORAEs among older NH residents.

PRIMARY FUNDING SOURCE

National Institute on Aging.

Combining Transcranial Direct Current Stimulation With Non-Invasive Interventions for Chronic Primary Pain: A Systematic Review and Meta-Analysis

BACKGROUND

A growing number of studies has combined transcranial direct current stimulation (tDCS) with other non-invasive non-pharmacological therapies (NINPT) to enhance effects in pain reduction. However, the efficacy of these combined approaches in treating chronic primary pain (CPP) warrants thorough investigation.

OBJECTIVE

This study aims to evaluate the efficacy of tDCS in conjunction with other NINPT in alleviating pain severity among CPP patients.

METHODS

We conducted a systematic search for randomized controlled trials (RCTs) comparing the efficacy of tDCS combined with NINPT against control treatments in adult CPP patients. The search spanned multiple databases, including PubMed, EMBASE, LILACS, Scopus, Web of Science, and CENTRAL.

RESULTS

Our systematic review included 11 RCTs with a total of 449 participants. In our meta-analysis, which comprised 228 participants receiving active-tDCS and 221 receiving sham-tDCS, we found a significant reduction in pain intensity (Standard Mean Difference = -0.73; 95% Confidence Interval (CI) = -1.18 to -0.27; P = .002) with the use of active-tDCS combined with NINPT.

CONCLUSION

These findings substantiate the therapeutic potential of combining tDCS with other NINPT, highlighting it as an effective treatment modality for reducing pain intensity in CPP patients.

Postoperative pain at Landspitali: A prospective study

BACKGROUND

Moderate or severe postoperative pain is common despite advances in surgical technique and perioperative analgesia. This study aimed to assess the prevalence and severity of postoperative pain following procedures requiring anaesthesia and identify factors associated with increased risk of postoperative pain.

METHODS

Surgical patients ≥18 years of age were prospectively questioned on level of current pain on a numerical rating scale (NRS) from 0 to 10 in the post-anaesthesia care unit (PACU) and on resting, active and worst pain experienced in the first 24 h postoperatively. Clinical data was obtained from medical records. Descriptive statistics were applied, and predictors of worst pain assessed as moderate/severe (NRS ≥ 5) on postoperative day one were assessed using multivariable logistic regression.

RESULTS

Of 438 included participants, moderate/severe pain occurred in 29% on the day of surgery and 70% described their worst pain as moderate/severe on postoperative day one. Procedures with the highest incidence of moderate/severe pain on the day of surgery were gynaecology-, plastic-, abdominal-, breast-, and orthopaedic procedures. On postoperative day one, patients undergoing vascular-, orthopaedic-, and abdominal operations most commonly rated their worst pain as moderate/severe. Female sex (OR = 2.15, 95% Cl 1.21-3.88, p = .010), chronic preoperative pain (OR = 4.20, 95% Cl 2.41-7.51, p < .001), undergoing a major procedure (OR = 2.07, 95% Cl 1.15-3.80, p = .017), and any intraoperative remifentanil administration (OR = 2.16, 95% Cl 1.20-3.94, p = .01) had increased odds of rating the worst pain as moderate/severe. Increased age (OR = 0.66 per 10 years (95% Cl 0.55-0.78, p < .001)) and undergoing breast-, gynaecology-, otolaryngology-, and neurosurgery (OR = 0.15-0.34, p < .038) was associated with lower odds of moderate/severe pain on postoperative day one.

DISCUSSION

In our cohort, patients rated their current pain in the PACU similarly to other studies. However, the ratio of patients rating the worst pain experienced as moderate/severe on postoperative day one was relatively high. The identified patient- and procedural-related factors associated with higher odds of postoperative pain highlight a subgroup of patients who may benefit from enhanced perioperative monitoring and pain management strategies.

The effect of the hand massage using baby oil with lavender application on the procedural pain and state anxiety of women undergoing brachytherapy: A parallel-group randomized controlled study

OBJECTIVE

This parallel-group randomized controlled study evaluated the effect of the hand massage practiced using baby oil with lavender on reducing pain and situational anxiety in women with brachytherapy.

METHODS

The study was completed with 36 patients. The treatment group included 18 patients, and the control group had 18. The data were collected through patient information form, visual analog scale, and state anxiety scale. Before the brachytherapy, three sessions of hand massages, each lasting 10 min (5 min for each hand), were performed using baby oil with lavender. Data collection forms were repeated after each session. The control group received routine treatment. Study groups were similar and homogeneous in terms of socio-demographic characteristics. The data obtained were assessed using Shapiro Wilk, Repeated Measures ANOVA, chi-square, and paired samples t-test.

RESULTS

At the end of the brachytherapy, the pain and state anxiety scores of the group that applied hand massage   were determined to be lower than the control group's at each three-time point (1st, 2nd, and 3rd-time points) (p<0.001).

CONCLUSION

It was determined that hand massage using baby oil with lavender effectively reduced pain and anxiety. It can be practiced by certified nurses in clinics that perform brachytherapy as a noninvasive, safe, and affordable practice.

Sympathetic nerve blocks for persistent pain in adults with inoperable abdominopelvic cancer

BACKGROUND

Persistent visceral pain is an unpleasant sensation coming from one or more organs within the body. Visceral pain is a common symptom in those with advanced cancer. Interventional procedures, such as neurolytic sympathetic nerve blocks, have been suggested as additional treatments that may play a part in optimising pain management for individuals with this condition.

OBJECTIVES

To evaluate the benefits and harms of neurolytic sympathetic nerve blocks for persistent visceral pain in adults with inoperable abdominopelvic cancer compared to standard care or placebo and comparing single blocks to combination blocks.

SEARCH METHODS

We searched the following databases without language restrictions on 19 October 2022 and ran a top-up search on 31 October 2023: CENTRAL; MEDLINE via Ovid; Embase via Ovid; LILACS. We searched trial registers without language restrictions on 2 November 2022: ClinicalTrials.gov; WHO International Clinical Trials Registry Platform (ICTRP). We searched grey literature, checked reference lists of reviews and retrieved articles for additional studies, and performed citation searches on key articles. We also contacted experts in the field for unpublished and ongoing trials. Our trial protocol was preregistered in the Cochrane Database of Systematic Reviews on 21 October 2022.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) comparing any sympathetic nerve block targeting sites commonly used to treat abdominal pelvic pain from inoperable malignancies in adults to standard care or placebo.

DATA COLLECTION AND ANALYSIS

We independently selected trials based on predefined inclusion criteria, resolving any differences via adjudication with a third review author. We used a random-effects model as some heterogeneity was expected between the studies due to differences in the interventions being assessed and malignancy types included in the study population. We chose three primary outcomes and four secondary outcomes of interest. We sought consumer input to refine our review outcomes and assessed extracted data using Cochrane's risk of bias 2 tool (RoB 2). We assessed the certainty of evidence using the GRADE system.

MAIN RESULTS

We included 17 studies with 1025 participants in this review. Fifteen studies with a total of 951 participants contributed to the quantitative analysis. Single block versus standard care Primary outcomes No included studies reported our primary outcome, 'Proportion of participants reporting no worse than mild pain after treatment at 14 days'. The evidence is very uncertain about the effect of sympathetic nerve blocks on reducing pain to no worse than mild pain at 14 days when compared to standard care due to insufficient data (very low-certainty evidence). Sympathetic nerve blocks may provide small to 'little to no' improvement in quality of life (QOL) scores at 14 days after treatment when compared to standard care, but the evidence is very uncertain (standardised mean difference (SMD) -0.73, 95% confidence interval (CI) -1.70 to 0.25; I² = 87%; 4 studies, 150 participants; very low-certainty evidence). The evidence is very uncertain about the risk of serious adverse events as defined in our review as only one study contributed data to this outcome. Sympathetic nerve blocks may have an 'increased risk' to 'no additional risk' of harm compared with standard care (very low-certainty evidence). Secondary outcomes Sympathetic nerve blocks showed a small to 'little to no' effect on participant-reported pain scores at 14 days using a 0 to 10 visual analogue scale (VAS) for pain compared with standard care, but the evidence is very uncertain (mean difference (MD) -0.44, 95% CI -0.98 to 0.11; I² = 56%; 5 studies, 214 participants; very low-certainty evidence). There may be a 'moderate to large' to 'little to no' reduction in daily consumption of opioids postprocedure at 14 days with sympathetic nerve blocks compared with standard care, but the evidence is very uncertain (change in daily consumption of opioids at 14 days as oral milligrams morphine equivalent (MME): MD -41.63 mg, 95% CI -78.54 mg to -4.72 mg; I² = 90%; 4 studies, 130 participants; very low-certainty evidence). The evidence is very uncertain about the effect of sympathetic nerve blocks on participant satisfaction with procedure at 0 to 7 days and time to need for retreatment or treatment effect failure (or both) due to insufficient data. Combination block versus single block Primary outcomes There is no evidence about the effect of combination sympathetic nerve blocks compared with single sympathetic nerve blocks on the proportion of participants reporting no worse than mild pain after treatment at 14 days because no studies reported this outcome. There may be a small to 'little to no' effect on QOL score at 14 days after treatment, but the evidence is very uncertain (very low-certainty evidence). The evidence is very uncertain about the risk of serious adverse events with combination sympathetic nerve blocks compared with single sympathetic nerve blocks due to limited reporting in the included studies (very low-certainty evidence). Secondary outcomes The evidence is very uncertain about the effect of combination sympathetic nerve blocks compared with single sympathetic nerve blocks on participant-reported pain score and change in daily consumption of opioids postprocedure, at 14 days. There may be a small to 'little to no' effect, but the evidence is very uncertain (very low-certainty evidence). There is no evidence about the effect on participant satisfaction with procedure at 0 to 7 days and time to need for retreatment or treatment effect failure (or both) due to these outcomes not being measured by the studies. Risk of bias The risk of bias was predominately high for most outcomes in most studies due to significant concerns regarding adequate blinding. Very few studies were deemed as low risk across all domains for any outcome.

AUTHORS' CONCLUSIONS

There is limited evidence to support or refute the use of sympathetic nerve blocks for persistent abdominopelvic pain due to inoperable malignancy. We are very uncertain about the effect of combination sympathetic nerve blocks compared with single sympathetic nerve blocks. The certainty of the evidence is very low and these findings should be interpreted with caution.

Transdermal Opioids and the Quality of Life of the Cancer Patient: A Systematic Literature Review

OBJECTIVE

This systematic literature review aims to evaluate the effectiveness of transdermal opioids in managing cancer pain and their impact on the quality of life (QoL) of patients.

DATA SOURCES

A systematic literature review conducted following the PRISMA protocol, focusing on randomized clinical trials found in the Lilacs, Embase, PubMed, and SciELO databases over the last 20 years.

STUDY SELECTION AND DATA EXTRACTION

We included randomized clinical trials, published in English, Portuguese, or Spanish, which assessed the impact of transdermal opioids on the QoL. Data extraction was facilitated using the Rayyan app.

DATA SYNTHESIS

Six articles meeting the inclusion and exclusion criteria were analyzed. These studies covered a population ranging from 24 to 422 cancer patients experiencing moderate to severe pain. The risk of bias was assessed in each study, generally being categorized as uncertain or high.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

The findings indicate that the analgesic effectiveness and side effects of transdermal formulations (specifically buprenorphine and fentanyl) for managing moderate to severe cancer pain are comparable to, or in some cases superior to, those of oral opioids traditionally employed.

CONCLUSIONS

Transdermal therapy was suggested to have several advantages over oral opioid therapy in enhancing cancer patients' QoL. These benefits span various dimensions, including pain management, physical functioning, mental health, vitality, overall patient improvement, anger/aversion, strength/activity, general QoL, cognitive and emotional functions, fatigue, and insomnia.

Acute Effects of a Warm-Up Intervention on Pain, Productivity, Physical Capacities and Psychological Perceptions Among Vineyard Workers: a Cluster Randomized Trial

PURPOSE

Agriculture is one of the sectors that are the most concerned by musculoskeletal disorders (MSDs). Workplace physical activity programs are one of the most promising solutions to prevent adverse consequences of MSDs such as pain or impairment in physical capacities. The aims of this study were twofold: (1) to investigate the acute effect of a warm-up session on pain, work performance, physical capacities and psychosocial perceptions among vineyard workers; (2) to determine the most beneficial warm-up modality for vineyard workers.

METHODS

A cluster randomized study was implemented among 92 French vineyard workers. A 15 min single session of warm-up was implemented among four groups corresponding to four different conditions: (1) hybrid warm-up intervention (HWU); (2) dynamic warm-up intervention (DWU); (3) stretching warm-up intervention (SWU); (4) no warm-up intervention (CONTROL).

RESULTS

DWU showed significant increased performance (p < 0.05), increased heart rate (p < 0.001), better readiness to work (p < 0.05) and lower workload (p < 0.05) than the CONTROL. HWU showed a better readiness to work (p < 0.01). SWU showed better work quality (p < 0.05). However, the three different warm-up protocols did significantly not differ from the CONTROL group in terms of perceived pain intensity, and physical capacities.

CONCLUSION

The present findings confirm some beneficial acute effects on performance, heart rate and psychological perceptions of a single warm-up session performed before pruning. The DWU seems to be the most beneficial warm-up modality.

TRIAL REGISTRATION

NCT05425693. Registered 06/16/2022 in www.

CLINICALTRIALS

gov .

Comparing pain intensity rating scales in acute postoperative pain: boundary values and category disagreements

Pain intensity assessment scales are important in evaluating postoperative pain and guiding management. Different scales can be used for patients to self-report their pain, but research determining cut points between mild, moderate and severe pain has been limited to studies with < 1500 patients. We examined 13,017 simultaneous acute postoperative pain ratings from 913 patients taken at rest and on activity, between 4 h and 48 h following surgery using both a verbal rating scale (no, mild, moderate or severe pain) and 0-100 mm visual analogue scale. We determined the best cut points on the visual analogue scale between mild and moderate pain as 35 mm, and moderate and severe pain as 80 mm. These remained consistent for pain at rest and on activity, and over time. We also explored the presence of category disagreements, defined as patients verbally describing no or mild pain scored above the mild/moderate cut point on the visual analogue scale, and patients verbally describing moderate or severe pain scored below the mild/moderate cut point on the visual analogue scale. Using 30 and 60 mm cut points, 1533 observations (12%) showed a category disagreement and using 35 and 80 mm cut points, 1632 (13%) showed a category disagreement. Around 1 in 8 simultaneous pain scores implausibly disagreed, possibly resulting in incorrect pain reporting. The reasons are not known but low rates of literacy and numeracy may be contributing factors. Understanding these disagreements between pain scales is important for pain research and medical practice.

Pain intensity, physical function, and depressive symptoms associated with discontinuing long-term opioid therapy in older adults with Alzheimer's disease and related dementias

INTRODUCTION

Limited evidence exists on the associations of discontinuing versus continuing long-term opioid therapy (LTOT) with pain intensity, physical function, and depression among patients with Alzheimer's disease and related dementias (ADRD).

METHODS

A cohort study among 138,059 older residents with mild-to-moderate ADRD and receipt of LTOT was conducted using a 100% Medicare nursing home sample. Discontinuation of LTOT was defined as no opioid refills for ≥ 60 days. Outcomes were worsening pain, physical function, and depression from baseline to quarterly assessments during 1- and 2-year follow-ups.

RESULTS

The adjusted odds of worsening pain and depressive symptoms were 29% and 5% lower at the 1-year follow-up and 35% and 9% lower at the 2-year follow-up for residents who discontinued versus continued LTOT, with no difference in physical function.

DISCUSSION

Discontinuing LTOT was associated with lower short- and long-term worsening pain and depressive symptoms than continuing LTOT among older residents with ADRD.

HIGHLIGHTS

Discontinuing long-term opioid therapy (LTOT) was associated with lower short- and long-term worsening pain. Discontinuing LTOT was related to lower short- and long-term worsening depression. Discontinuing LTOT was not associated with short- and long-term physical function.

A global comparative study of wealth-pain gradients: Investigating individual- and country-level associations

Pain is a significant yet underappreciated dimension of population health. Its associations with individual- and country-level wealth are not well characterized using global data. We estimate both individual- and country-level wealth inequalities in pain in 51 countries by combining data from the World Health Organization's World Health Survey with country-level contextual data. Our research concentrates on three questions: 1) Are inequalities in pain by individual-level wealth observed in countries worldwide? 2) Does country-level wealth also relate to pain prevalence? 3) Can variations in pain reporting also be explained by country-level contextual factors, such as income inequality? Analytical steps include logistic regressions conducted for separate countries, and multilevel models with random wealth slopes and resultant predicted probabilities using a dataset that pools information across countries. Findings show individual-level wealth negatively predicts pain almost universally, but the association strength differs across countries. Country-level contextual factors do not explain away these associations. Pain is generally less prevalent in wealthier countries, but the exact nature of the association between country-level wealth and pain depends on the moderating influence of country-level income inequality, measured by the Gini index. The lower the income inequality, the more likely it is that poor countries experience the highest and rich countries the lowest prevalence of pain. In contrast, the higher the income inequality, the more nonlinear the association between country-level wealth and pain reporting such that the highest prevalence is seen in highly nonegalitarian middle-income countries. Our findings help to characterize the global distribution of pain and pain inequalities, and to identify national-level factors that shape pain inequalities.

Chronic Pain and Functional Outcome 3 years After Total Knee Arthroplasty and Perioperative Dexamethasone: A Follow-Up of the Randomized, Clinical DEX-2-TKA Trial

BACKGROUND

Perioperative dexamethasone as an adjunct to multimodal analgesia, has an opioid-sparing and pain alleviating effect after total knee arthroplasty (TKA), however, the 3-year effects are unknown. We aimed to investigate the 3-year effect of 1 (DX1) or 2 (DX2) intravenous doses of 24 mg dexamethasone or placebo on pain, physical function, and health-related quality of life after TKA.

METHODS

Patients who participated in the Dexamethasone Twice for Pain Treatment after TKA (DEX-2-TKA) were invited to physical tests and questionnaires (self-reported characteristics, Oxford Knee Score, EuroQol-5Dimensions-5Levels (EQ5D5L), and PainDetect). The tests were 40-meter Fast Paced Walk (40FPW) test, Timed Up and Go (TUG), 30 Second Chair Stand test (30CST), Stair Climb Test (SCT), bilateral knee Range of Motion, and knee extension torque. For each test the peak pain intensity was registered on a 0 to 100 mm Visual Analogue Scale. Primary outcome was average peak pain intensity during the 40FPW, TUG, 30CST and SCT. Secondary outcomes were the tests and questionnaires. Out of 252 eligible patients, 133 (52.8%) underwent the tests and 160 (63.5%) answered the questionnaires. Mean follow-up time was 33 months (range, 23 to 40).

RESULTS

Median (interquartile range) peak pain intensity was 0 (0 to 65) for the DX2 group, 0 (0 to 51) for DX1 group and 0 (0 to 70) for the placebo group (P = .72). No differences in secondary outcomes were identified.

CONCLUSION

One or 2 intravenous doses of 24 mg dexamethasone did not impact chronic pain development or physical function 3 years after TKA.

Personalized pain assessment: What does 'acceptable pain' mean to you?

BACKGROUND

What 'acceptable pain' means may be different for everyone and dependent on the moment and the context. In this text, we explore the concepts of pain acceptability and acceptance. We explain why we need to better explore (un)acceptable pain, to eventually facilitate pain assessment and management.

METHODS

Using different approaches and perspectives (with examples and application from multiple disciplines, i.e. orthopaedics, psychology, pharmacological therapy), we discussed anecdotal examples and included a systematic, scoping and literature review.

RESULTS

We rejected the idea that in the context of chronic pain, acceptability, disability and manageability overlap neatly. Additionally, we rejected the validity of pain intensity rating scales to sufficiently explore individuals' experience of pain. In the one study that met our criteria, a definition of 'acceptable pain' was dropped as participants deemed it inappropriate because it did not address the significant challenges associated with pain. This is important, however, because the acceptability of pain may precede, follow and/or inform the 'pain acceptance' process, which is an important concept associated with better outcomes.

CONCLUSIONS

Very little is known regarding what 'acceptable pain' may mean to people living with pain. Qualitative studies may improve our understanding of individuals' perceptions, perspectives and expectations as we do not know, for the moment, what 'acceptable pain' may mean to a particular person and, potentially, regarding a specific treatment or other contextual aspects that are not captured with currently used scores and quantitative measures.

SIGNIFICANCE

What does 'acceptable pain' mean may differ between people with painful experiences and may depend on contextual factors. Pain acceptability may be distinct from manageability, and may precede, follow and/or inform the 'pain acceptance' process. This text, rigorously based on a review of the existing literature, defends the idea that acceptable pain should be better studied.

Topical ophthalmic anesthetics for corneal abrasions

BACKGROUND

Despite potential analgesic benefits from topical ophthalmic amides and esters, their outpatient use has become of concern because of the potential for abuse and ophthalmic complications.

OBJECTIVES

To assess the effectiveness and safety of topical ophthalmic anesthetics compared with placebo or other treatments in persons with corneal abrasions.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; Embase.com; Latin American and Caribbean Health Sciences (LILACS); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), without restriction on language or year of publication. The search was performed on 10 February 2023.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of topical ophthalmic anesthetics alone or in combination with another treatment (e.g. nonsteroidal anti-inflammatory drugs (NSAIDs)) versus a non-anesthetic control group (e.g. placebo, non-treatment, or alternative treatment). We included trials that enrolled participants of all ages who had corneal abrasions within 48 hours of presentation.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology.

MAIN RESULTS

We included nine parallel-group RCTs with a total of 556 participants (median number of participants per study: 45, interquartile range (IQR) 44 to 74), conducted in eight countries: Australia, Canada, France, South Korea, Turkey, New Zealand, UK, and USA. Study characteristics and risk of bias Four RCTs (314 participants) investigated post-traumatic corneal abrasions diagnosed in the emergency department setting. Five trials described 242 participants from ophthalmology surgery centers with post-surgical corneal defects: four from photorefractive keratectomy (PRK) and one from pterygium surgery. Study duration ranged from two days to six months, the most common being one week (four RCTs). Treatment duration ranged from three hours to one week (nine RCTs); the majority were between 24 and 48 hours (five RCTs). The age of participants was reported in eight studies, ranging from 17 to 74 years of age. Only one participant in one trial was under 18 years of age. Of four studies that reported funding sources, none was industry-sponsored. We judged a high risk of bias in one trial with respect to the outcome pain control by 48 hours, and in five of seven trials with respect to the outcome complications at the furthest time point. The domain for which we assessed studies to be at the highest risk of bias was missing or selective reporting of outcome data. Findings The treatments investigated included topical anesthetics compared with placebo, topical anesthetic compared with NSAID (post-surgical cases), and topical anesthetics plus NSAID compared with placebo (post-surgical cases). Pain control by 24 hours In all studies, self-reported pain outcomes were on a 10-point scale, where lower numbers represent less pain. In post-surgical trials, topical anesthetics provided a moderate reduction in self-reported pain at 24 hours compared with placebo of 1.28 points on a 10-point scale (mean difference (MD) -1.28, 95% confidence interval (CI) -1.76 to -0.80; 3 RCTs, 119 participants). In the post-trauma participants, there may be little or no difference in effect (MD -0.04, 95% CI -0.10 to 0.02; 1 RCT, 76 participants). Compared with NSAID in post-surgical participants, topical anesthetics resulted in a slight increase in pain at 24 hours (MD 0.82, 95% CI 0.01 to 1.63; 1 RCT, 74 participants). One RCT compared topical anesthetics plus NSAID to placebo. There may be a large reduction in pain at 24 hours with topical anesthetics plus NSAID in post-surgical participants, but the evidence to support this large effect is very uncertain (MD -5.72, 95% CI -7.35 to -4.09; 1 RCT, 30 participants; very low-certainty evidence). Pain control by 48 hours Compared with placebo, topical anesthetics reduced post-trauma pain substantially by 48 hours (MD -5.68, 95% CI -6.38 to -4.98; 1 RCT, 111 participants) but had little to no effect on post-surgical pain (MD 0.41, 95% CI -0.45 to 1.27; 1 RCT, 44 participants), although the evidence is very uncertain. Pain control by 72 hours One post-surgical RCT showed little or no effect of topical anesthetics compared with placebo by 72 hours (MD 0.49, 95% CI -0.06 to 1.04; 44 participants; very low-certainty evidence). Proportion of participants with unresolved epithelial defects When compared with placebo or NSAID, topical anesthetics increased the number of participants without complete resolution of defects in trials of post-trauma participants (risk ratio (RR) 1.37, 95% CI 0.78 to 2.42; 3 RCTs, 221 participants; very low-certainty evidence). The proportion of placebo-treated post-surgical participants with unresolved epithelial defects at 24 to 72 hours was lower when compared with those assigned to topical anesthetics (RR 0.14, 95% CI 0.01 to 2.55; 1 RCT, 30 participants; very low-certainty evidence) or topical anesthetics plus NSAID (RR 0.33, 95% CI 0.04 to 2.85; 1 RCT, 30 participants; very low-certainty evidence). Proportion of participants with complications at the longest follow-up When compared with placebo or NSAID, topical anesthetics resulted in a higher proportion of post-trauma participants with complications at up to two weeks (RR 1.13, 95% CI 0.23 to 5.46; 3 RCTs, 242 participants) and post-surgical participants with complications at up to one week (RR 7.00, 95% CI 0.38 to 128.02; 1 RCT, 44 participants). When topical anesthetic plus NSAID was compared with placebo, no complications were reported in either treatment arm up to one week post-surgery (risk difference (RD) 0.00, 95% CI -0.12 to 0.12; 1 RCT, 30 participants). The evidence is very uncertain for safety outcomes. Quality of life None of the included trials assessed quality of life outcomes.

AUTHORS' CONCLUSIONS

Despite topical anesthetics providing excellent pain control in the intraoperative setting, the currently available evidence provides little or no certainty about their efficacy for reducing ocular pain in the initial 24 to 72 hours after a corneal abrasion, whether from unintentional trauma or surgery. We have very low confidence in this evidence as a basis to recommend topical anesthetics as an efficacious treatment modality to relieve pain from corneal abrasions. We also found no evidence of a substantial effect on epithelial healing up to 72 hours or a reduction in ocular complications when we compared anesthetics alone or with NSAIDs versus placebo.

Neuropsychological Function in Traumatic Brain Injury and the Influence of Chronic Pain

Cognitive dysfunction, pain, and psychological morbidity all present unique challenges to those living with traumatic brain injury (TBI). In this study we examined (a) the impact of pain across domains of attention, memory, and executive function, and (b) the relationships between pain and depression, anxiety, and post-traumatic stress disorder (PTSD) in persons with chronic TBI. Our sample included 86 participants with a TBI and chronic pain (n = 26), patients with TBI and no chronic pain (n = 23), and a pain-free control group without TBI (n = 37). Participants visited the laboratory and completed a comprehensive battery of neuropsychological tests as part of a structured interview. Multivariate analysis of covariance using education as a covariate, failed to detect a significant group difference for neuropsychological composite scores of attention, memory, and executive function (p = .165). A follow-up analysis using multiple one-way analysis of variance (ANOVA) was conducted for individual measures of executive function. Post-hoc testing indicated that those in both TBI groups preformed significantly worse on measures of semantic fluency when compared to controls (p < 0.001, ηρ2 = .16). Additionally, multiple ANOVAs indicated that those with TBI and pain scored significantly worse across all psychological assessments (p < .001). We also found significant associations between measures of pain and most psychological symptoms. A follow-up stepwise linear regression among those in the TBI pain group indicated that post concussive complaints, pain severity, and neuropathic pain symptoms differentially contributed to symptoms of depression, anxiety, and PTSD. These findings suggest deficits in verbal fluency among those living with chronic TBI, with results also reinforcing the multidimensional nature of pain and its psychological significance in this population.

Pain Prevalence and Management in a General Hospital Through Repeated Cross-Sectional Surveys in 2011 and 2021

Background

There is great scope for improving the quality of pain management. Although pain prevalence has been investigated in several countries, few studies have comparatively assessed changes in pain prevalence and management over a span of multiple years.

Aim

This work was aimed at determining the pain prevalence and evaluating the condition of pain management in a Chinese general hospital in 2021 and comparing them with corresponding data from 10 years ago.

Methods

Repeated single-center cross-sectional studies were initiated on June 14th, 2011, and September 2nd, 2021, in the same tertiary grade A Chinese general hospital. The same structured questionnaire was used to collect inpatient data on pain intensity and classification and pain management outcomes. We performed statistical analyses to compare categorical variables to assess changes over time.

Results

The sample sizes for the investigations in 2011 and 2021 were 2323 and 4454, respectively. In 2021, 24.34% of patients experienced pain; this percentage was significantly lower than that in 2011. Meanwhile, the prevalence of moderate and severe pain decreased from 14.73% in 2011 to 4.98% in 2021. The other six indicators of pain management outcomes also improved significantly. The percentages of patients using painkillers, opioid analgesics, and multiple analgesics increased from 44.61 to 51.38%, 24.01% to 44.61%, and 6.82% to 14.11%, respectively. Furthermore, the percentages of patients who received pain information and who actively reported pain increased from 27.56% to 96.5% and from 85.54% to 98.71%, respectively. The percentage of patients qualified to accurately use the Numerical Rating Scale increased from 10.5% to 79.98%.

Conclusion

The quality and outcomes of pain management improved greatly after the establishment and implementation of the pain management system. Nonetheless, pain of different intensities is common after major surgeries, and it is recommended that hospitals popularize and implement perioperative multimodal analgesia strategies to reduce the incidence of postoperative pain.

Comparison of dental anesthetic efficacy between the periodontal intraligamentary anesthesia and other infiltration anesthesia: a systematic review and meta-analysis

Background

Uncertainty exists regarding the pain scores and the success rate of intraligamentary anesthesia compared to other infiltration anesthesia. Based on the conditions of clinical anesthesia techniques, we conducted a systematic review and meta-analysis to compare the efficacy of intraligamentary anesthesia with other infiltration anesthesia.

Methods

The search was carried out in PubMed Central, Cochrane Central Register of Controlled Trials, MEDLINE (via OVID), Embase (via OVID), and Scopus from the inception to March 26, 2023.

Results

Seven eligible randomized controlled trials were included in the meta-analysis. The results indicated no significant difference in the success rate (RR = 0.96; 95% CI [0.81-1.14]; p = 0.65; I²= 73%) and visual analog scale (VAS) during dental procedures (MD = 3.81; 95% CI [-0.54-8.16]; p = 0.09; I²= 97%) between intraligamentary anesthesia and other infiltration anesthesia. However, intraligamentary anesthesia exhibited a higher VAS score during injection than other infiltration anesthesia (MD = 8.83; 95% CI [4.86-12.79]; p < 0.0001; I²= 90%). A subgroup analysis according to infiltration techniques showed that supraperiosteal anesthesia had a lower VAS score during dental procedures than intraligamentary anesthesia.

Conclusions

Intraligamentary anesthesia and other infiltration anesthesias have the same success rate and pain during dental procedures. However, the pain during injection of intraligamentary anesthesia is heavier than that of other infiltration anesthesia.

Pain and participation in social activities in people with relapsing remitting and progressive multiple sclerosis

Background

Differences in pain between subtypes of multiple sclerosis are understudied.

Objective

To compare the prevalence of pain, and the association between pain and: (a) pain interference and (b) social participation in people with relapsing-remitting multiple sclerosis and progressive multiple sclerosis.

Methods

Participants completed the McGill Pain Questionnaire Short-Form-2, Pain Effects Scale and Ability to Participate in Social Roles and Activities-V2.0 questionnaires. We tested the association between multiple sclerosis subtype, pain severity, and pain interference/social participation using quantile regression.

Results

Of 231 participants (relapsing-remitting multiple sclerosis: 161, progressive multiple sclerosis: 70), 82.3% were women. The prevalence of pain was 95.2%, of more than mild pain was 38.1%, and of pain-related limitations was 87%; there were no differences between multiple sclerosis subtypes. Compared to participants with relapsing-remitting multiple sclerosis, those with progressive multiple sclerosis reported higher pain interference (mean (standard deviation) Pain Effects Scale; progressive multiple sclerosis: 15[6.0] vs relapsing-remitting multiple sclerosis: 13[5], p = 0.039) and lower social participation (Ability to Participate in Social Roles and Activities T-scores 45[9.0] vs 48.3[8.9], p = 0.011). However, on multivariable analysis accounting for age, physical disability, mood/anxiety and fatigue, multiple sclerosis subtype was not associated with differences in pain interference or social participation.

Conclusions

Pain was nearly ubiquitous. Over one-third of individuals with relapsing-remitting multiple sclerosis and progressive multiple sclerosis reported pronounced pain, although this did not differ by multiple sclerosis subtype.

Cannabis-based medicines and medical cannabis for adults with cancer pain

BACKGROUND

Pain is a common symptom in people with cancer; 30% to 50% of people with cancer will experience moderate-to-severe pain. This can have a major negative impact on their quality of life. Opioid (morphine-like) medications are commonly used to treat moderate or severe cancer pain, and are recommended for this purpose in the World Health Organization (WHO) pain treatment ladder. Pain is not sufficiently relieved by opioid medications in 10% to 15% of people with cancer. In people with insufficient relief of cancer pain, new analgesics are needed to effectively and safely supplement or replace opioids.

OBJECTIVES

To evaluate the benefits and harms of cannabis-based medicines, including medical cannabis, for treating pain and other symptoms in adults with cancer compared to placebo or any other established analgesic for cancer pain.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 26 January 2023.

SELECTION CRITERIA

We selected double-blind randomised, controlled trials (RCT) of medical cannabis, plant-derived and synthetic cannabis-based medicines against placebo or any other active treatment for cancer pain in adults, with any treatment duration and at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. The primary outcomes were 1. proportions of participants reporting no worse than mild pain; 2. Patient Global Impression of Change (PGIC) of much improved or very much improved and 3. withdrawals due to adverse events. Secondary outcomes were 4. number of participants who reported pain relief of 30% or greater and overall opioid use reduced or stable; 5. number of participants who reported pain relief of 30% or greater, or 50% or greater; 6. pain intensity; 7. sleep problems; 8. depression and anxiety; 9. daily maintenance and breakthrough opioid dosage; 10. dropouts due to lack of efficacy; 11. all central nervous system adverse events. We used GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We identified 14 studies involving 1823 participants. No study assessed the proportions of participants reporting no worse than mild pain on treatment by 14 days after start of treatment. We found five RCTs assessing oromucosal nabiximols (tetrahydrocannabinol (THC) and cannabidiol (CBD)) or THC alone involving 1539 participants with moderate or severe pain despite opioid therapy. The double-blind periods of the RCTs ranged between two and five weeks. Four studies with a parallel design and 1333 participants were available for meta-analysis. There was moderate-certainty evidence that there was no clinically relevant benefit for proportions of PGIC much or very much improved (risk difference (RD) 0.06, 95% confidence interval (CI) 0.01 to 0.12; number needed to treat for an additional beneficial outcome (NNTB) 16, 95% CI 8 to 100). There was moderate-certainty evidence for no clinically relevant difference in the proportion of withdrawals due to adverse events (RD 0.04, 95% CI 0 to 0.08; number needed to treat for an additional harmful outcome (NNTH) 25, 95% CI 16 to endless). There was moderate-certainty evidence for no difference between nabiximols or THC and placebo in the frequency of serious adverse events (RD 0.02, 95% CI -0.03 to 0.07). There was moderate-certainty evidence that nabiximols and THC used as add-on treatment for opioid-refractory cancer pain did not differ from placebo in reducing mean pain intensity (standardised mean difference (SMD) -0.19, 95% CI -0.40 to 0.02). There was low-certainty evidence that a synthetic THC analogue (nabilone) delivered over eight weeks was not superior to placebo in reducing pain associated with chemotherapy or radiochemotherapy in people with head and neck cancer and non-small cell lung cancer (2 studies, 89 participants, qualitative analysis). Analyses of tolerability and safety were not possible for these studies. There was low-certainty evidence that synthetic THC analogues were superior to placebo (SMD -0.98, 95% CI -1.36 to -0.60), but not superior to low-dose codeine (SMD 0.03, 95% CI -0.25 to 0.32; 5 single-dose trials; 126 participants) in reducing moderate-to-severe cancer pain after cessation of previous analgesic treatment for three to four and a half hours (2 single-dose trials; 66 participants). Analyses of tolerability and safety were not possible for these studies. There was low-certainty evidence that CBD oil did not add value to specialist palliative care alone in the reduction of pain intensity in people with advanced cancer. There was no difference in the number of dropouts due to adverse events and serious adverse events (1 study, 144 participants, qualitative analysis). We found no studies using herbal cannabis.

AUTHORS' CONCLUSIONS

There is moderate-certainty evidence that oromucosal nabiximols and THC are ineffective in relieving moderate-to-severe opioid-refractory cancer pain. There is low-certainty evidence that nabilone is ineffective in reducing pain associated with (radio-) chemotherapy in people with head and neck cancer and non-small cell lung cancer. There is low-certainty evidence that a single dose of synthetic THC analogues is not superior to a single low-dose morphine equivalent in reducing moderate-to-severe cancer pain. There is low-certainty evidence that CBD does not add value to specialist palliative care alone in the reduction of pain in people with advanced cancer.

Pain in the joints and beyond; the challenge of rheumatoid arthritis

Pain is a common and often debilitating symptom for people living with rheumatoid arthritis. Although pain is a generic feature of inflammation and often improves with successful treatment that targets inflammatory pathways, pain experience can persist. Emerging data suggest that the magnitude of pain relief might vary according to the therapeutic target of pharmacological intervention within the inflammatory cascade. Both inflammatory and non-inflammatory causes contribute to the pain experience, which depends on tissue origin, peripheral sensory mechanisms and their transmission, integration, and interpretation within the nervous system. Contemporary neuroimaging is transforming our understanding of these mechanisms and the role of sensory, emotional, and cognitive contributions to the experience of pain. This understanding paves the way for therapeutic approaches that recognise the existence of multiple, cognitively driven, supraspinal mechanisms for pain modulation and could complement pharmacological inflammation suppression. Such approaches include neuropsychological interventions that have the potential to modify human brain cortical structure and reduce suffering that is often associated with pain experience.

Minimal important difference in opioid consumption based on adverse event reduction-A study protocol

BACKGROUND

The patient-relevant minimal important difference for opioid consumption remains undetermined, despite its frequent use as primary outcome in trials on postoperative pain management. A minimal important difference is necessary to evaluate whether significant trial results are clinically relevant. Further, it can be used as effect size to ensure that trials are powered to find clinically relevant effects. By exploring the dose-response relationship between postoperative opioid consumption and opioid-related adverse effects, we aim to approximate the minimal important difference in opioid consumption anchored to opioid-related adverse effects.

METHODS

This is a post-hoc analysis of aggregated data from two clinical trials (PANSAID NCT02571361 and DEX2TKA NCT03506789) and one observational cohort study (Pain Map NCT02340052) on pain management after total hip and knee arthroplasty. The primary outcome is the Hodges-Lehmann median difference in opioid consumption between patients with no opioid-related adverse effects and patients experiencing the mildest degree of one or more opioid-related adverse effects (i.e., mild nausea, sedation and/or dizziness or vomiting). Secondary outcomes include the Hodges-Lehmann median difference in opioid consumption that corresponds to one point on a cumulated opioid-related adverse event 0-10 scale. Further, we will explore the proportion of patients that experience opioid-related adverse effects for consecutive opioid dose intervals of 2 mg iv morphine equivalents. Quantile regression will be used to assess any significant interactions with patient baseline characteristics.

CONCLUSIONS

This study will hopefully bring us one step closer to determining relevant opioid reductions and thereby improve our understanding of intervention effects and planning of future trials.

Acute Effects of a Session with The EXOPULSE Mollii Suit in a Fibromyalgia Patient: A Case Report

Fibromyalgia is a chronic disorder characterized by widespread musculoskeletal pain and associated fatigue, sleep disturbances, and other cognitive and somatic symptoms. A multidisciplinary approach including pharmacological therapies along with behavioral therapy, exercise, patient education, and pain management is a possible solution for the treatment of this disease. The EXOPULSE Mollii^® method (EXONEURAL NETWORK AB, Danderyd, Sweden) is an innovative approach for non-invasive and self-administered electrical stimulation with multiple electrodes incorporated in a full-body suit, with already proven benefits for other diseases. Therefore, the present case report study aims to evaluate the effects that a 60 min session with the EXOPULSE Mollii suit has on a female fibromyalgia patient. After the intervention, we can conclude that a 60 min session with the EXOPULSE Mollii suit has beneficial effects on pain perception, muscle oxygenation, parasympathetic modulation, and function in a female fibromyalgia patient.

Internet-delivered treatment for patients suffering from severe functional somatic disorders: Protocol for a randomized controlled trial

Background

Functional somatic disorders (FSDs) with symptoms from multiple organs, i.e., multi-system type, are common in the general population and may lead to disability and reduced quality of life. Evidence for efficient treatment programs has been established, however, there is a need for making treatments accessible to a larger group of patients. Internet-delivered therapy has become prevalent and has proven as effective as face-to-face therapy, while providing a flexible and easily accessible treatment alternative. The aim of the current study is to compare the efficacy of the therapist-assisted internet-delivered treatment program One step at a time (OneStep) with the internet-delivered self-help program Get started (GetStarted).

Methods

A total of 166 participants aged 18-60 years diagnosed with multi-system FSD will be assessed and randomized to either 1) OneStep: a 14-week program consisting of 11 treatment modules based on principles from cognitive behavioural therapy or 2) GetStarted consisting of 1 module on psychoeducation. The primary outcome is physical health, assessed by a Short Form Health Survey (SF-36) aggregate score of the subscales vitality, physical functioning, and bodily pain 3 months after end-of-treatment and self-reported improvement assessed by the Clinical Global Improvement Scale. Secondary outcomes include symptom load, depression, anxiety, and illness worry. Process measures include emotional distress, illness perception, illness behaviour, and symptom interference.

Conclusions

This study is the first study to test an internet-delivered treatment program for FSD, multi-system type and has the potential to show the importance of making evidence-based internet-delivered treatment for FSD more accessible.

Postoperative Pain Management and Patient Evaluations After Five Different Surgical Procedures. A Prospective Cohort Study

BACKGROUND

Sufficient pain management is a necessity and can play an important role in patients' contentment.

AIMS

To investigate the instituted postoperative pain treatment, patients' levels of pain, opioid consumption, and patient contentment, supplemented with a questionnaire based on the International Pain Outcome (IPO).

METHODS

This prospective observational cohort study was conducted at Zealand University Hospital Køge, Denmark (ZUHK) from March 8, 2017, to January 7, 2019, aiming for a consecutive inclusion of 200 patients, 40 from five major surgical procedures. The study was approved by the Danish Data Protection Agency (REG-121-2016) and registered at ClinicalTrials.gov (NCT03080272). The Research Ethics Committee of the Zealand Region was consulted, but approval was not needed according to Danish law (J.nr. 16-000014).

RESULTS

We included 189 patients in total. We found a significant number of patients that did not achieve "no worse than mild pain" (Numeric Rating Scale ≤3) across surgical procedures. The provided pain treatment was heterogenic and inconsistent even among individuals who underwent similar surgical procedures. Although patients did not achieve "no worse than mild pain" (Numeric Rating Scale ≤3), the majority stated that they were content with their pain treatment.

CONCLUSIONS

The analgesic treatment varied between procedures and patients and a significant number of patients did not achieve "no worse than mild pain" (Numeric Rating Scale ≤3). A significant association between patient contentment and experience of severe pain, pain relief, and involvement in own pain treatment, was found.

Transversus abdominis plane (TAP) blocks for prevention of postoperative pain in women undergoing laparoscopic and robotic gynaecological surgery

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To evaluate the benefits and harms of TAP blocks for the prevention of postoperative pain in women undergoing laparoscopic and robotic gynaecological surgery compared to no block, sham block, or injection of local anaesthetic. 

Brain Connectivity Predicts Chronic Pain in Acute Mild Traumatic Brain Injury

OBJECTIVES

Previous studies have established the role of the cortico-mesolimbic and descending pain modulation systems in chronic pain prediction. Mild traumatic brain injury (mTBI) is an acute pain model where chronic pain is prevalent and complicated for prediction. In this study, we set out to study whether functional connectivity (FC) of the nucleus accumbens (NAc) and the periaqueductal gray matter (PAG) is predictive of pain chronification in early-acute mTBI.

METHODS

To estimate FC, resting-state functional magnetic resonance imaging (fMRI) of 105 participants with mTBI following a motor vehicle collision was acquired within 72 hours post-accident. Participants were classified according to pain ratings provided at 12-months post-collision into chronic pain (head/neck pain ≥30/100, n = 44) and recovery (n = 61) groups, and their FC maps were compared.

RESULTS

The chronic pain group exhibited reduced negative FC between NAc and a region within the primary motor cortex corresponding with the expected representation of the area of injury. A complementary pattern was also demonstrated between PAG and the primary somatosensory cortex. PAG and NAc also shared increased FC to the rostral anterior cingulate cortex (rACC) within the recovery group. Brain connectivity further shows high classification accuracy (area under the curve [AUC] = .86) for future chronic pain, when combined with an acute pain intensity report.

INTERPRETATION

FC features obtained shortly after mTBI predict its transition to long-term chronic pain, and may reflect an underlying interaction of injury-related primary sensorimotor cortical areas with the mesolimbic and pain modulation systems. Our findings indicate a potential predictive biomarker and highlight targets for future early preventive interventions. ANN NEUROL 2022;92:819-833.

New insight into the analgesic recipe: A cohort study based on smart patient-controlled analgesia pumps records

Purpose: Intravenous patient-controlled analgesia (IV-PCA) has been widely used; however, regimen criteria have not yet been established. In China, the most often used opioid is sufentanil, for which repeated doses are a concern, and empirical flurbiprofen axetil (FBP) as an adjuvant. We hypothesized that hydromorphone would be a better choice and also evaluated the effectiveness of FBP as an adjuvant.

Methods: This historical cohort study was conducted in two tertiary hospitals in China and included 12,674 patients using hydromorphone or sufentanil for IV-PCA between April 1, 2017, and January 30, 2021. The primary outcome was analgesic insufficiency at static (AIS). The secondary outcomes included analgesic insufficiency with movement (AIM) and common opioid-related adverse effects such as postoperative nausea and vomiting (PONV) and dizziness.

Results: Sufentanil, but not the sufentanil-FBP combination, was associated with higher risks of AIS and AIM compared to those for hydromorphone (OR 1.64 [1.23, 2.19], p < 0.001 and OR 1.42 [1.16, 1.73], p < 0.001). Hydromorphone combined with FBP also decreased the risk of both AIS and AIM compared to those for pure hydromorphone (OR 0.74 [0.61, 0.90], p = 0.003 and OR 0.80 [0.71, 0.91], p < 0.001). However, the risk of PONV was higher in patients aged ≤35 years using FBP (hydromorphone-FBP vs. hydromorphone and sufentanil-FBP vs. hydromorphone, OR 1.69 [1.22, 2.33], p = 0.001 and 1.79 [1.12, 2.86], p = 0.015).

Conclusion: Hydromorphone was superior to sufentanil for IV-PCA in postoperative analgesia. Adding FBP may improve the analgesic effects of both hydromorphone and sufentanil but was associated with an increased risk of PONV in patients <35 years of age.

A global study of pain prevalence across 52 countries: examining the role of country-level contextual factors

ABSTRACT

There is wide variation in population-level pain prevalence estimates in studies of survey data around the world. The role of country-level social, economic, and political contextual factors in explaining this variation has not been adequately examined. We estimated the prevalence of unspecified pain in adults aged 25+ years across 52 countries using data from the World Health Survey 2002 to 2004. Combining data sources and estimating multilevel regressions, we compared country-level pain prevalence and explored which country-level contextual factors explain cross-country variations in prevalence, accounting for individual-level demographic factors. The overall weighted age- and sex-standardized prevalence of pain across countries was estimated to be 27.5%, with significant variation across countries (ranging from 9.9% to 50.3%). Women, older persons, and rural residents were significantly more likely to report pain. Five country-level variables had robust and significant associations with pain prevalence: the Gini Index, population density, the Gender Inequality Index, life expectancy, and global region. The model including Gender Inequality Index explained the most cross-country variance. However, even when accounting for country-level variables, some variation in pain prevalence remains, suggesting a complex interaction between personal, local, economic, and political impacts, as well as inherent differences in language, interpretations of health, and other difficult to assess cultural idiosyncrasies. The results give new insight into the high prevalence of pain around the world and its demonstrated association with macrofactors, particularly income and gender inequalities, providing justification for regarding pain as a global health priority.

An international open-label randomised trial comparing a two-step approach versus the standard three-step approach of the WHO analgesic ladder in patients with cancer

BACKGROUND

Worldwide, cancer pain management follows the World Health Organization (WHO) three-step analgesic ladder. Using weak opioids (e.g. codeine) at step 2 is debatable with low-dose strong opioids being potentially better, particularly in low- and middle-income countries where weak opioids are expensive. We wanted to assess the efficiency, safety and cost of omitting step 2 of the WHO ladder.

PATIENTS AND METHODS

We carried out an international, open-label, randomised (1 : 1) parallel group trial. Eligible patients had cancer, pain ≥4/10 on a 0-10 numerical rating scale, required at least step 1 (paracetamol) of the WHO ladder and were randomised to the control arm (weak opioid, step 2 of the WHO ladder) or the experimental arm (strong opioid, step 3). Primary outcome was time to stable pain control (3 consecutive days with pain ≤3). Secondary outcomes included distress, opioid-related side-effects and costs. The primary outcome analysis was by intention to treat and the follow-up was for 20 days.

RESULTS

One hundred and fifty-three patients were randomised (76 control, 77 experimental). There was no statistically significant difference in time to stable pain control between the arms, P = 0.667 (log-rank test). The adjusted hazard ratio for the control arm was 1.03 (95% confidence interval 0.72-1.49). In the control arm, 38 patients (53%) needed to change to a strong opioid due to ineffective analgesia. The median time to change was day 6 (interquartile range 4-11). Compared to the control arm, patients in the experimental arm had less nausea (P = 0.009) and costs were less.

CONCLUSION

This trial provides some evidence that the two-step approach is an alternative option for cancer pain management.

Topical clonidine for neuropathic pain in adults

BACKGROUND

Clonidine is a presynaptic alpha-2-adrenergic receptor agonist that has been used for many years to treat hypertension and other conditions, including chronic pain. Adverse events associated with systemic use of the drug have limited its application. Topical use of drugs has been gaining interest since the beginning of the century, as it may limit adverse events without loss of analgesic efficacy. Topical clonidine (TC) formulations have been investigated for almost 20 years in clinical trials. This is an update of the original Cochrane Review published in Issue 8, 2015.

OBJECTIVES

The objective of this review was to assess the analgesic efficacy and safety of TC compared with placebo or other drugs in adults aged 18 years or above with chronic neuropathic pain.

SEARCH METHODS

For this update we searched the Cochrane Register of Studies Online (CRSO), MEDLINE (Ovid), and Embase (Ovid) databases, and reference lists of retrieved papers and trial registries. We also contacted experts in the field. The most recent search was performed on 27 October 2021.

SELECTION CRITERIA

We included randomised, double-blind studies of at least two weeks' duration comparing TC versus placebo or other active treatment in adults with chronic neuropathic pain.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened references for eligibility, extracted data, and assessed risk of bias. Any discrepancies were resolved by discussion or by consulting a third review author if necessary. Where required, we contacted trial authors to request additional information. We presented pooled estimates for dichotomous outcomes as risk ratios (RRs) with 95% confidence intervals (CIs), and continuous outcomes as mean differences (MDs) with P values. We used Review Manager Web software to perform the meta-analyses. We used a fixed-effect model if we considered heterogeneity as not important; otherwise, we used a random-effects model.  The review primary outcomes were: participant-reported pain relief of 50% or greater; participant-reported pain relief of 30% or greater; much or very much improved on Patient Global Impression of Change scale (PGIC); and very much improved on PGIC. Secondary outcomes included withdrawals due to adverse events; participants experiencing at least one adverse event; and withdrawals due to lack of efficacy. All outcomes were measured at the longest follow-up period. We assessed the certainty of evidence using GRADE and created two summary of findings tables.

MAIN RESULTS

We included four studies in the review (two new in this update), with a total of 743 participants with painful diabetic neuropathy (PDN). TC (0.1% or 0.2%) was applied in gel form to the painful area two to three times daily. The double-blind treatment phase of three studies lasted 8 weeks to 85 days and compared TC versus placebo. In the fourth study, the double-blind treatment phase lasted 12 weeks and compared TC versus topical capsaicin. We assessed the studies as at unclear or high risk of bias for most domains; all studies were at unclear risk of bias for allocation concealment and blinding of outcome assessment; one study was at high risk of bias for blinding of participants and personnel; two studies were at high risk of attrition bias; and three studies were at high risk of bias due to notable funding concerns. We judged the certainty of evidence (GRADE) to be moderate to very low, downgrading for study limitations, imprecision of results, and publication bias. TC compared to placebo There was no evidence of a difference in number of participants with participant-reported pain relief of 50% or greater during longest follow-up period (12 weeks) between groups (risk ratio (RR) 1.21, 95% confidence interval (CI) 0.78 to 1.86; 179 participants; 1 study; low certainty evidence). However, the number of participants with participant-reported pain relief of 30% or greater during longest follow-up period (8 to 12 weeks) was higher in the TC group compared with placebo (RR 1.35, 95% CI 1.03 to 1.77; 344 participants; 2 studies, very low certainty evidence). The number needed to treat for an additional beneficial outcome (NNTB) for this comparison was 8.33 (95% CI 4.3 to 50.0). Also, there was no evidence of a difference between groups for the outcomes much or very much improved on the PGIC during longest follow-up period (12 weeks) or very much improved on PGIC during the longest follow-up period (12 weeks) (RR 1.06, 95% CI 0.76 to 1.49 and RR 1.82, 95% CI 0.89 to 3.72, respectively; 179 participants; 1 study; low certainty evidence). We observed no evidence of a difference between groups in withdrawals due to adverse events and withdrawals due to lack of efficacy during the longest follow-up period (12 weeks) (RR 0.34, 95% CI 0.04 to 3.18 and RR 1.01, 95% CI 0.06 to 15.92, respectively; 179 participants; 1 study; low certainty evidence) and participants experiencing at least one adverse event during longest follow-up period (12 weeks) (RR 0.65, 95% CI 0.14 to 3.05; 344 participants; 2 studies; low certainty evidence).  TC compared to active comparator There was no evidence of a difference in the number of participants with participant-reported pain relief of 50% or greater during longest follow-up period (12 weeks) between groups (RR 1.41, 95% CI 0.99 to 2.0; 139 participants; 1 study; low certainty evidence). Other outcomes were not reported.

AUTHORS' CONCLUSIONS

This is an update of a review published in 2015, for which our conclusions remain unchanged. Topical clonidine may provide some benefit to adults with painful diabetic neuropathy; however, the evidence is very uncertain. Additional trials are needed to assess TC in other neuropathic pain conditions and to determine whether it is possible to predict who or which groups of people will benefit from TC.

Patient-reported outcomes and realistic clinical endpoints for JAK inhibitors in rheumatoid arthritis

INTRODUCTION

Despite development of multiple classes of therapeutics, health related quality of life in RA remains low. Patients describe impacts of their disease in differing terms than health care providers. (HCPs), stressing importance of pain, fatigue, poor sleep and restrictions in work and social participation.

AREAS COVERED

Patient reported outcomes (PROs) assessed and analyzed across the phase 3 randomized controlled trials (RCTs) in RA with the JAK inhibitors (JAKis) are summarized. Patient populations, whether conventional synthetic disease modifying anti-rheumatic drug incomplete responders (csDMARD-IR) or biologic DMARD incomplete responders (bDMARD-IR) or csDMARD-naive, report differing baseline scores and placebo responses, generally lower in more treatment experienced patients. Improvements with all the approved JAKis in RA occur rapidly and are often maximal by 12 - 14 weeks; continuing thereafter. The rapidity of benefit reported by patients and convenience of oral administration often lead to increased adherence.

EXPERT OPINION

A broad variety of PROs utilized in the RA RCTs with the JAKis confirm the clinical meaningfulness of their efficacy across treatment-experienced and naive populations. A majority of patients report statistically significant as well as clinically meaningful (≥ minimum clinically important differences, MCID) improvements, with numbers needed to treat (NNTs) ≤ 10 and scores ≥ normative values at endpoint, despite ≤ 12% reporting such scores at baseline.

Qualitative interview study exploring the patient experience of living with axial spondyloarthritis and fatigue: difficult, demanding and draining

OBJECTIVE

To explore patients' lived experiences of axial spondyloarthritis (axSpA) and fatigue.

DESIGN

Interpretative phenomenological analysis (lived experience) was used as the study design. Analysis drew together codes with similar meaning to create superordinate and subordinate themes.

SETTING

Rheumatology departments in three National Health Service Foundation Trusts in the north, midlands and south of England.

PARTICIPANTS

A purposive sample of seventeen axSpA patients were recruited. The age range was 22-72 years (median age 46), nine were male and eight, female.

RESULTS

A central concept of achieving balance was identified as the active process of integrating axSpA symptoms and fatigue into daily life, working with and not against their condition to lead a fulfilled life. This was conveyed through three superordinate themes: struggling to find energy, engaging in everyday life and persevering through difficulties. Struggling to find energy was the challenge of retaining enough stamina to do things in daily life. Engaging in everyday life highlighted dedication to being active and organised, learning through experience and acceptance of a changed way of being. Persevering through difficulties identified the physical and emotional effort required to keep moving forward and the importance of feeling supported.

CONCLUSION

Achieving balance through finding energy, engaging and persevering everyday was fundamental to having the best possible life. The experience of energy emerged as a distinct but related component of fatigue. However, while energy could be maintained or replenished, fatigue was more difficult to overcome and required greater effort. Energy may be a useful indicator of an individual's current state and ability to sustain activities that supports their well-being, such as exercise. Awareness of the elements of achieving balance in axSpA may enable patients and clinicians to work together to tailor treatments to individual patient need.

Systematic reviews do not (yet) represent the 'gold standard' of evidence: A position paper

The low quality of included trials, insufficient rigour in review methodology, ignorance of key pain issues, small size, and over-optimistic judgements about the direction and magnitude of treatment effects all devalue systematic reviews, supposedly the 'gold standard' of evidence. Available evidence indicates that almost all systematic reviews in the published literature contain fatal flaws likely to make their conclusions incorrect and misleading. Only 3 in every 100 systematic reviews are deemed to have adequate methods and be clinically useful. Examples of research waste and questionable ethical standards abound: most trials have little hope of providing useful results, and systematic review of hopeless trials inspires no confidence. We argue that results of most systematic reviews should be dismissed. Forensically critical systematic reviews are essential tools to improve the quality of trials and should be encouraged and protected.

Background pain in persons with chronic leg ulcers: An exploratory study of symptom characteristics and management

This exploratory descriptive study aimed to describe characteristics and management of background pain related to chronic leg ulcers. A total of 121 participants were recruited from two wound care clinics using a consecutive sampling method. Data were obtained through screening interview, clinical examination, and questionnaires. The mean average background pain intensity was 4.5 (SD 2.56) (CI 95% 4.0-5.0). Pain interfered mostly with general activity (mean 4.3), sleep (mean 4.1), and walking ability (mean 4.0) (0-10 NRS). The most frequently reported descriptors of background pain were 'tender', 'stabbing', 'aching', and 'hot-burning'. Most of the participants stated that the pain was intermittent. Less than 60% had analgesics prescribed specifically for ulcer related pain, and the respondents reported that pain management provided a mean pain relief of 45.9% (SD 33.9, range 0-100). The findings indicate that ulcer related background pain is a significant problem that interferes with daily function, and that pain management in wound care is still inadequate.

Selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors as adjuncts for postoperative pain management: systematic review and meta-analysis of randomised controlled trials

BACKGROUND

We conducted a systematic review and meta-analysis to assess effects of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) as adjuncts for postoperative pain management.

METHODS

We searched seven databases and two trial registers from inception to February 2021 for RCTs that compared SSRIs or SNRIs with placebo or an active control for postoperative pain management.

RESULTS

We included 24 RCTs with 2197 surgical patients (21 trials for SNRIs and three trials for SSRIs). Moderate-quality evidence found that, compared with placebo, SSRIs/SNRIs (majority SNRIs) significantly reduced postoperative pain within 6 h {weighted mean difference (WMD) -0.73 cm on a 10 cm VAS (95% confidence interval [CI]: -1.04 to -0.42)}, 12 h (-0.68 cm [-1.28 to -0.07]), 24 h (-0.68 cm [-1.16 to -0.20]), 48 h (-0.73 cm [-1.22 to -0.23]), 10 days to 1 month (-0.71 cm [-1.11 to -0.31]), 3 months (-0.64 cm [-1.05 to -0.22]), and 6 months (-0.95 cm [-1.64 to -0.25]), and opioid consumption within 24 h (WMD -12 mg [95% CI: -16 to -8]) and 48 h (-10 mg [-15 to -5]), and improved patient satisfaction (WMD 0.49 point on a 1-4 Likert scale [95% CI: 0.09 to 0.89]) without significant increase in adverse events. Selective serotonin reuptake inhibitors tended to be less effective despite non-significant subgroup effects.

CONCLUSIONS

Serotonin-norepinephrine reuptake inhibitors as an adjunct to standard perioperative care probably provide small reduction in both acute and chronic postoperative pain and opioid consumption, and small improvement in patient satisfaction without increases in adverse events. The effects of SSRIs are inconclusive because of very limited evidence.

Therapeutic Effects of Ba-Duan-Jin versus Pregabalin for Fibromyalgia Treatment: Protocol for a Randomized Controlled Trial

INTRODUCTION

Fibromyalgia is characterized by multi-focal pain and is associated with fatigue, unrefreshing sleep and psychological impairment. Pregabalin is one of the most frequently used agents in fibromyalgia treatment. However, it has failed to demonstrate benefit over placebo for reducing fatigue and psychological impairment, and may cause adverse effects (e.g. somnolence, dizziness). "Ba-Duan-Jin" (BDJ) is a common form of "Qigong" exercise for health promotion in China. Growing evidence suggests that BDJ may achieve satisfactory control of fibromyalgia-related symptoms in Chinese patients. Therefore, we wish to ascertain if BDJ could overcome the disadvantages of pregabalin.

METHODS

A single-blind randomized controlled trial has been designed which will recruit 104 patients with fibromyalgia (age 18-70 years) with a visual analog scale (VAS) pain score of ≥ 40 mm These patients will be randomly assigned to one of two groups: (1) BDJ group (to undertake guided BDJ exercise and take a placebo capsule) or (2) pregabalin group (to take a pregabalin capsule and receive wellness education and guided muscle-relaxation exercises). The primary endpoint will be changes in the VAS score for pain. The secondary endpoints will be changes in the score for the Revised Fibromyalgia Impact Questionnaire, Multidimensional Fatigue Inventory-20, Pittsburgh Sleep Quality Index, Beck II Depression Inventory, Perceived Stress Scale and Short Form-36 Health Survey Questionnaire. These parameters will be assessed at 0, 4, 8, 12 and 24 weeks of follow-up.

PLANNED OUTCOMES

Our results are expected to provide more clinical evidence for the beneficial effects of BDJ in treating fibromyalgia.

TRIAL REGISTRATION

NCT03797560.

Hydromorphone for cancer pain

BACKGROUND

This is an update of the original Cochrane Review first published in Issue 10, 2016. For people with advanced cancer, the prevalence of pain can be as high as 90%. Cancer pain is a distressing symptom that tends to worsen as the disease progresses. Evidence suggests that opioid pharmacotherapy is the most effective of these therapies. Hydromorphone appears to be an alternative opioid analgesic which may help relieve these symptoms.

OBJECTIVES

To determine the analgesic efficacy of hydromorphone in relieving cancer pain, as well as the incidence and severity of any adverse events.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and clinical trials registers in November 2020. We applied no language, document type or publication status limitations to the search.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared hydromorphone with placebo, an alternative opioid or another active control, for cancer pain in adults and children. Primary outcomes were participant-reported pain intensity and pain relief; secondary outcomes were specific adverse events, serious adverse events, quality of life, leaving the study early and death.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. We calculated risk ratio (RR) and 95% confidence intervals (CI) for binary outcomes on an intention-to-treat (ITT) basis. We estimated mean difference (MD) between groups and 95% CI for continuous data. We used a random-effects model and assessed risk of bias for all included studies. We assessed the evidence using GRADE and created three summary of findings tables.

MAIN RESULTS

With four new identified studies, the review includes a total of eight studies (1283 participants, with data for 1181 participants available for analysis), which compared hydromorphone with oxycodone (four studies), morphine (three studies) or fentanyl (one study). All studies included adults with cancer pain, mean age ranged around 53 to 59 years and the proportion of men ranged from 42% to 67.4%. We judged all the studies at high risk of bias overall because they had at least one domain with high risk of bias. We found no studies including children. We did not complete a meta-analysis for the primary outcome of pain intensity due to skewed data and different comparators investigated across the studies (oxycodone, morphine and fentanyl). Comparison 1: hydromorphone compared with placebo We identified no studies comparing hydromorphone with placebo. Comparison 2: hydromorphone compared with oxycodone Participant-reported pain intensity We found no clear evidence of a difference in pain intensity (measured using a visual analogue scale (VAS)) in people treated with hydromorphone compared with those treated with oxycodone, but the evidence is very uncertain (3 RCTs, 381 participants, very low-certainty evidence). Participant-reported pain relief We found no studies reporting participant-reported pain relief. Specific adverse events We found no clear evidence of a difference in nausea (RR 1.13 95% CI 0.74 to 1.73; 3 RCTs, 622 participants), vomiting (RR 1.18, 95% CI 0.72 to 1.94; 3 RCTs, 622 participants), dizziness (RR 0.91, 95% CI 0.58 to 1.44; 2 RCTs, 441 participants) and constipation (RR 0.92, 95% CI 0.72 to 1.19; 622 participants) (all very low-certainty evidence) in people treated with hydromorphone compared with those treated with oxycodone, but the evidence is very uncertain. Quality of life We found no studies reporting quality of life. Comparison 3: hydromorphone compared with morphine Participant-reported pain intensity We found no clear evidence of a difference in pain intensity (measured using the Brief Pain Inventory (BPI) or VAS)) in people treated with hydromorphone compared with those treated with morphine, but the evidence is very uncertain (2 RCTs, 433 participants; very low-certainty evidence). Participant-reported pain relief We found no clear evidence of a difference in the number of clinically improved participants, defined by 50% or greater pain relief rate, in the hydromorphone group compared with the morphine group, but the evidence is very uncertain (RR 0.99, 95% CI 0.84 to 1.18; 1 RCT, 233 participants; very low-certainty evidence). Specific adverse events At 24 days of treatment, morphine may reduce constipation compared with hydromorphone, but the evidence is very uncertain (RR 1.56, 95% CI 1.12 to 2.17; 1 RCT, 200 participants; very low-certainty evidence). We found no clear evidence of a difference in nausea (RR 0.94, 95% CI 0.66 to 1.30; 1 RCT, 200 participants), vomiting (RR 0.87, 95% CI 0.58 to 1.31; 1 RCT, 200 participants) and dizziness (RR 1.15, 95% CI 0.71 to 1.88; 1 RCT, 200 participants) (all very low-certainty evidence) in people treated with hydromorphone compared with those treated with morphine, but the evidence is very uncertain. Quality of life We found no studies reporting quality of life. Comparison 4: hydromorphone compared with fentanyl Participant-reported pain intensity We found no clear evidence of a difference in pain intensity (measured by numerical rating scale (NRS)) at 60 minutes in people treated with hydromorphone compared with those treated with fentanyl, but the evidence is very uncertain (1 RCT, 82 participants; very low-certainty evidence). Participant-reported pain relief We found no studies reporting participant-reported pain relief. Specific adverse events We found no studies reporting specific adverse events. Quality of life We found no studies reporting quality of life.

AUTHORS' CONCLUSIONS

The evidence of the benefits and harms of hydromorphone compared with other analgesics is very uncertain. The studies reported some adverse events, such as nausea, vomiting, dizziness and constipation, but generally there was no clear evidence of a difference between hydromorphone and morphine, oxycodone or fentanyl for this outcome. There is insufficient evidence to support or refute the use of hydromorphone for cancer pain in comparison with other analgesics on the reported outcomes. Further research with larger sample sizes and more comprehensive outcome data collection is required.

A Sham-Controlled Study of Neurofeedback for Pain Management

Background

Neurofeedback (NFB) attempts to alter the brain’s electrophysiological activity and has shown potential as a pain management technique. Existing studies, however, often lack appropriate control groups or fail to assess whether electrophysiological activity has been successfully regulated. The current study is a randomized controlled trial comparing changes in brain activity and pain during NFB with those of a sham-control group.

Methods

An experimental pain paradigm in healthy participants was used to provide optimal control of pain sensation. Twenty four healthy participants were blind randomized to receive either 10 × NFB (with real EEG feedback) or 10 × sham (with false EEG feedback) sessions during noxious cold stimulation. Prior to actual NFB training, training protocols were individually determined for each participant based on a comparison of an initial 32-channel qEEG assessment administered at both baseline and during an experimental pain task. Each individual protocol was based on the electrode site and frequency band that showed the greatest change in amplitude during pain, with alpha or theta up-regulation at various electrode sites (especially Pz) the most common protocols chosen. During the NFB sessions themselves, pain was assessed at multiple times during each session on a 0–10 rating scale, and ANOVA was used to examine changes in pain ratings and EEG amplitude both across and during sessions for both NFB and sham groups.

Results

For pain, ANOVA trend analysis found a significant general linear decrease in pain across the 10 sessions (p = 0.015). However, no significant main or interaction effects of group were observed suggesting decreases in pain occurred independently of NFB. For EEG, there was a significant During Session X Group interaction (p = 0.004), which indicated that EEG amplitude at the training site was significantly closer to the target amplitude for the NFB compared to the sham group during painful stimulation, but this was only the case at the beginning of the cold task.

Conclusion

While these results must be interpreted within the context of an experimental pain model, they underline the importance of including an appropriate comparison group to avoid attributing naturally occurring changes to therapeutic effects.

Cannabinoids, cannabis, and cannabis-based medicines for pain management: an overview of systematic reviews

ABSTRACT

Cannabinoids, cannabis, and cannabis-based medicines (CBM) are increasingly used to manage pain, with limited understanding of their efficacy and safety. We assessed methodological quality, scope, and results of systematic reviews of randomised controlled trials of these treatments. Several search strategies sought self-declared systematic reviews. Methodological quality was assessed using both AMSTAR-2 and techniques important for bias reduction in pain studies. Of the 106 articles read, 57 were self-declared systematic reviews, most published since 2010. They included any type of cannabinoid, cannabis, or CBM, at any dose, however administered, in a broad range of pain conditions. No review examined the effects of a particular cannabinoid, at a particular dose, using a particular route of administration, for a particular pain condition, reporting a particular analgesic outcome. Confidence in the results in the systematic reviews using AMSTAR-2 definitions was critically low (41), low (8), moderate (6), or high (2). Few used criteria important for bias reduction in pain. Cochrane reviews typically provided higher confidence; all industry-conflicted reviews provided critically low confidence. Meta-analyses typically pooled widely disparate studies, and, where assessable, were subject to potential publication bias. Systematic reviews with positive or negative recommendation for use of cannabinoids, cannabis, or CBM in pain typically rated critically low or low (24/25 [96%] positive; 10/12 [83%] negative). Current reviews are mostly lacking in quality and cannot provide a basis for decision-making. A new high-quality systematic review of randomised controlled trials is needed to critically assess the clinical evidence for cannabinoids, cannabis, or CBM in pain.

Transversus abdominis plane block in urological procedures: A systematic review and meta-analysis

BACKGROUND

Transversus abdominis plane (TAP) blocks have been shown to successfully reduce pain and opioid consumption after general and gynaecological surgery.

OBJECTIVE

To evaluate whether TAP blocks alleviate pain and opioid consumption after urological procedures.

DESIGN

A systematic review and meta-analysis.

DATA SOURCES

MEDLINE, Embase and CENTRAL.

ELIGIBILITY CRITERIA

Without language restriction, randomised controlled trials (RCTs) that compared the effects of TAP blocks with placebo or no treatment in urological surgery.

MAIN OUTCOME MEASURES

Primary outcomes were pain intensities at rest and movement at 6, 12 and 24 h after surgery. Secondary outcomes were postoperative opioid consumption in the first 24 h after surgery and postoperative nausea and vomiting. We performed meta-analyses using random effects models. Effect sizes were expressed as mean differences for continuous variables. We used the Cochrane risk of bias tool (RoB 2.0) to assess risk of bias.

RESULTS

We analysed 20 RCTs comprising a total of 1239 patients. The risk of bias of the studies was relatively high. TAP blocks significantly reduced postoperative pain at all time points compared with placebo or no treatment. Mean differences on an 11-point pain intensity scale were between 0.55 (95% CI: -0.90, to -0.21; P = 0.002; I2 = 94%) to 1.13 (95% CI: -1.62 to -0.65; P < 0.001; I2 = 95%) less at rest and 0.74 (95% CI: -1.25 to -0.23; P = 0.005; I2 = 79%) to 1.32 (95% CI: -1.83 to -0.81; P < 0.001; I2 = 68%) less on movements. TAP blocks also reduced opioid consumption in the first 24 h after surgery significantly by 12.25 mg (95% CI: -17.99 to -6.52 mg; P < 0.001; I2 = 99%) morphine equivalents. Possibly, this had no influence on postoperative nausea and vomiting (risk ratio: 0.98; 95% CI: 0.66 to 1.45; P = 0.91; I2 = 30%).

CONCLUSION

TAP blocks seem to offer improved analgesia when used after urological surgery. However, due to the large heterogeneity between and the considerable risk of bias within the included studies results should be viewed with caution.

SYSTEMIC REVIEW REGISTRATION

PROSPERO CRD42018112737.

Pre-emptive and preventive NSAIDs for postoperative pain in adults undergoing all types of surgery

BACKGROUND

Postoperative pain is a common consequence of surgery and can have many negative perioperative effects. It has been suggested that the administration of analgesia before a painful stimulus may improve pain control. We defined pre-emptive nonsteroidal anti-inflammatories (NSAIDs) as those given before surgery but not continued afterwards and preventive NSAIDs as those given before surgery and continued afterwards. These were compared to a control group given the NSAIDs after surgery instead of before surgery.

OBJECTIVES

To assess the efficacy of preventive and pre-emptive NSAIDs for reducing postoperative pain in adults undergoing all types of surgery.

SEARCH METHODS

We searched the following electronic databases: CENTRAL, MEDLINE, Embase, AMED and CINAHL (up to June 2020). In addition, we searched for unpublished studies in three clinical trial databases, conference proceedings, grey literature databases, and reference lists of retrieved articles. We did not apply any restrictions on language or date of publication.

SELECTION CRITERIA

We included parallel-group randomized controlled trials (RCTs) only. We included adult participants undergoing any type of surgery. We defined pre-emptive NSAIDs as those given before surgery but not continued afterwards and preventive NSAIDs as those given before surgery and continued afterwards. These were compared to a control group given the NSAIDs after surgery instead of before surgery. We included studies that gave the medication by any route but not given on the skin.

DATA COLLECTION AND ANALYSIS

We used the standard methods expected by Cochrane, as well as a novel publication bias test developed by our research group. We used GRADE to assess the certainty of the evidence for each outcome. Outcomes included acute postoperative pain (minimal clinically important difference (MCID): 1.5 on a 0-10 scale), adverse events of NSAIDs, nausea and vomiting, 24-hour morphine consumption (MCID: 10 mg reduction), time to analgesic request (MCID: one hour), pruritus, sedation, patient satisfaction, chronic pain and time to first bowel movement (MCID: 12 hours).

MAIN RESULTS

We included 71 RCTs. Seven studies are awaiting classification. We included 45 studies that evaluated pre-emptive NSAIDs and 26 studies that evaluated preventive NSAIDs. We considered only four studies to be at low risk of bias for most domains. The operations and NSAIDs used varied, although most studies were conducted in abdominal, orthopaedic and dental surgery. Most studies were conducted in secondary care and in low-risk participants. Common exclusions were participants on analgesic medications prior to surgery and those with chronic pain. Pre-emptive NSAIDs compared to post-incision NSAIDs For pre-emptive NSAIDs, there is probably a decrease in early acute postoperative pain (MD -0.69, 95% CI -0.97 to -0.41; studies = 36; participants = 2032; I2 = 96%; moderate-certainty evidence). None of the included studies that reported on acute postoperative pain reported adverse events as an outcome. There may be little or no difference between the groups in short-term (RR 1.00, 95% CI 0.34 to 2.94; studies = 2; participants = 100; I2 = 0%; low-certainty evidence) or long-term nausea and vomiting (RR 0.85, 95% CI 0.52 to 1.38; studies = 5; participants = 228; I2 = 29%; low-certainty evidence). There may be a reduction in late acute postoperative pain (MD -0.22, 95% CI -0.44 to 0.00; studies = 28; participants = 1645; I2 = 97%; low-certainty evidence). There may be a reduction in 24-hour morphine consumption with pre-emptive NSAIDs (MD -5.62 mg, 95% CI -9.00 mg to -2.24 mg; studies = 16; participants = 854; I2 = 99%; low-certainty evidence) and an increase in the time to analgesic request (MD 17.04 minutes, 95% CI 3.77 minutes to 30.31 minutes; studies = 18; participants = 975; I2 = 95%; low-certainty evidence). There may be little or no difference in opioid adverse events such as pruritus (RR 0.40, 95% CI 0.09 to 1.76; studies = 4; participants = 254; I2 = 0%; low-certainty evidence) or sedation (RR 0.51, 95% CI 0.16 to 1.68; studies = 4; participants = 281; I2 = 0%; low-certainty evidence), although the number of included studies for these outcomes was small. No study reported patient satisfaction, chronic pain or time to first bowel movement for pre-emptive NSAIDs. Preventive NSAIDs compared to post-incision NSAIDs For preventive NSAIDs, there may be little or no difference in early acute postoperative pain (MD -0.14, 95% CI -0.39 to 0.12; studies = 18; participants = 1140; I2 = 75%; low-certainty evidence). One study reported adverse events from NSAIDs (reoperation for bleeding) although the events were low which did not allow any meaningful conclusions to be drawn (RR 1.95; 95% CI 0.18 to 20.68). There may be little or no difference in rates of short-term (RR 1.26, 95% CI 0.49 to 3.30; studies = 1; participants = 76; low-certainty evidence) or long-term (RR 0.85, 95% CI 0.52 to 1.38; studies = 5; participants = 456; I2 = 29%; low-certainty evidence) nausea and vomiting. There may be a reduction in late acute postoperative pain (MD -0.33, 95% CI -0.59 to -0.07; studies = 21; participants = 1441; I2 = 81%; low-certainty evidence). There is probably a reduction in 24-hour morphine consumption (MD -1.93 mg, 95% CI -3.55 mg to -0.32 mg; studies = 16; participants = 1323; I2 = 49%; moderate-certainty evidence). It is uncertain if there is any difference in time to analgesic request (MD 8.51 minutes, 95% CI -31.24 minutes to 48.27 minutes; studies = 8; participants = 410; I2 = 98%; very low-certainty evidence). As with pre-emptive NSAIDs, there may be little or no difference in other opioid adverse events such as pruritus (RR 0.56, 95% CI 0.09 to 3.35; studies = 3; participants = 211; I2 = 0%; low-certainty evidence) and sedation (RR 0.84, 95% CI 0.44 to 1.63; studies = 5; participants = 497; I2 = 0%; low-certainty evidence). There is probably little or no difference in patient satisfaction (MD -0.42; 95% CI -1.09 to 0.25; studies = 1; participants = 72; moderate-certainty evidence). No study reported on chronic pain. There is probably little or no difference in time to first bowel movement (MD 0.00; 95% CI -15.99 to 15.99; studies = 1; participants = 76; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

There was some evidence that pre-emptive and preventive NSAIDs reduce both pain and morphine consumption, although this was not universal for all pain and morphine consumption outcomes. Any differences found were not clinically significant, although we cannot exclude this in more painful operations. Moreover, without any evidence of reductions in opioid adverse effects, the clinical significance of these results is questionable although few studies reported these outcomes. Only one study reported clinically significant adverse events from NSAIDs administered before surgery and, therefore, we have very few data to assess the safety of either pre-emptive or preventive NSAIDs. Therefore, future research should aim to adhere to the highest methodology and be adequately powered to assess serious adverse events of NSAIDs and reductions in opioid adverse events.

Short-Term and Long-Term Pain After Total Hip Arthroplasty: A Prospective Cohort Study

BACKGROUND

Postoperative pain has a major influence on older adults' rehabilitation. There is a lack of knowledge regarding how older adults return to daily living after discharge.

AIMS

The primary aim of this study was to examine the association between moderate to severe pain during the first 5 postoperative days and pain 1 year after discharge in older adults after total hip arthroplasty (THA).

DESIGN

This was a prospective cohort study.

METHODS

The study was conducted from August 2019 to February 2020, in a University Hospital in Denmark and included a 5-day diary and a telephone interview postoperatively. The following main areas were investigated: pain levels, pain management, side effects from opioids, mood, fatigue, quality of sleep, and functional level. Associations between moderate to severe pain levels at 5 days after surgery and persistent pain at 1 year were evaluated through correlation analyses.

RESULTS

A total of 70 THA older adults returned the diary postoperatively. Thereafter, 62 participated in a 1-year follow-up interview. No associations were found between pain levels 5 days postoperatively and after 1 year. Fifteen older adults reported hip pain was present still 1 year after surgery, and 14 patients still used analgesics on daily basis. No correlation was found between levels of pain and quality of sleep 1 year after surgery.

CONCLUSIONS

No association was found between older adults with moderate to severe levels of pain during the first 5 days postoperatively and 1 year after surgery. Proactive follow-up strategies for older adults after discharge following THA may be indicated to promote optimal rehabilitation.

Association between sleep disturbance and low back and pelvic pain in 4-month postpartum women: A cross-sectional study

PURPOSE

Persistent low back and pelvic pain (LBPP) is a postpartum-specific health problem. Sleep disturbances' association with persistent LBPP is not yet clear. We aimed to examine the cross-sectional association between sleep disturbance and persistent LBPP at 4 months postpartum.

METHODS

We enrolled 120 women with LBPP during pregnancy (mean age, 31.8; standard deviation, 4.9 years). The primary outcome was persistent LBPP. We assessed LBPP severity at 4 months postpartum using the Numerical Rating Scale (NRS), where women with an NRS score of ≥ 4 at 4 months postpartum were allocated to the persistent LBPP group. We assessed sleep disturbance at 4 months postpartum using the Japanese version of the Pittsburgh Sleep Quality Index with a total score of ≥ 6 indicating sleep disturbance. Moreover, we performed univariate and multiple logistic regression analyses to examine the cross-sectional association of sleep disturbance with persistent LBPP. The relevant confounding variables were age, body mass index, parity, and history of LBPP before pregnancy.

RESULTS

Among the 120 women, 45 women had persistent LBPP (37.5%) with 32 (71.1%) of them reporting sleep disturbance. There was a significant association of sleep disturbance with persistent LBPP (odds ratio [OR], 2.81; 95% confidence interval [95% CI], 1.28-6.19), which remained after adjustments for confounding variables (OR, 2.98; 95% CI, 1.31-6.75).

CONCLUSION

Our findings indicate that sleep disturbance is associated with persistent LBPP at 4 months postpartum; therefore, it should be taken into consideration in postpartum women with persistent LBPP.

Dimethyl Trisulfide Diminishes Traumatic Neuropathic Pain Acting on TRPA1 Receptors in Mice

Pharmacotherapy of neuropathic pain is still challenging. Our earlier work indicated an analgesic effect of dimethyl trisulfide (DMTS), which was mediated by somatostatin released from nociceptor nerve endings acting on SST₄ receptors. Somatostatin release occurred due to TRPA1 ion channel activation. In the present study, we investigated the effect of DMTS in neuropathic pain evoked by partial ligation of the sciatic nerve in mice. Expression of the mRNA of Trpa1 in murine dorsal-root-ganglion neurons was detected by RNAscope. Involvement of TRPA1 ion channels and SST₄ receptors was tested with gene-deleted animals. Macrophage activity at the site of the nerve lesion was determined by lucigenin bioluminescence. Density and activation of microglia in the spinal cord dorsal horn was verified by immunohistochemistry and image analysis. Trpa1 mRNA is expressed in peptidergic and non-peptidergic neurons in the dorsal root ganglion. DMTS ameliorated neuropathic pain in Trpa1 and Sstr4 WT mice, but not in KO ones. DMTS had no effect on macrophage activity around the damaged nerve. Microglial density in the dorsal horn was reduced by DMTS independently from TRPA1. No effect on microglial activation was detected. DMTS might offer a novel therapeutic opportunity in the complementary treatment of neuropathic pain.

Estimands and missing data in clinical trials of chronic pain treatments: advances in design and analysis

In clinical trials of treatments for chronic pain, the percentage of participants who withdraw early can be as high as 50%. Major reasons for early withdrawal in these studies include perceived lack of efficacy and adverse events. Commonly used strategies for accommodating missing data include last observation carried forward, baseline observation carried forward, and more principled methods such as mixed-model repeated-measures and multiple imputation. All these methods require strong and untestable assumptions concerning the conditional distribution of outcomes after dropout, given the observed data. We review recent developments in statistical methods for handling missing data in clinical trials, including implications of the increased emphasis being placed on precise formulation of the study objectives and the estimand (treatment effect to be estimated) of interest. A flexible method that seems to be well suited for the analysis of chronic pain clinical trials is control-based imputation, which allows a variety of assumptions to be made concerning the conditional distribution of postdropout outcomes that can be tailored to the estimand of interest. These assumptions can depend, for example, on the stated reasons for dropout. We illustrate these methods using data from 4 clinical trials of pregabalin for the treatment of painful diabetic peripheral neuropathy and postherpetic neuralgia. When planning chronic pain clinical trials, careful consideration of the trial objectives should determine the definition of the trial estimand, which in turn should inform methods used to accommodate missing data in the statistical analysis.

Prevalence and impact of comorbid chronic pain and cigarette smoking among people living with HIV

Rates of chronic pain and cigarette smoking are each substantially higher among people living with HIV (PLWH) than in the general population. The goal of these analyses was to examine the prevalence and impact of comorbid chronic pain and cigarette smoking among PLWH. Participants included 3289 PLWH (83% male) who were recruited from five HIV clinics. As expected, the prevalence of smoking was higher among PLWH with chronic pain (41.9%), than PLWH without chronic pain (26.6%, p < .0001), and the prevalence of chronic pain was higher among current smokers (32.9%), than among former (23.6%) or never (17%) smokers (ps < .0001). PLWH who endorsed comorbid chronic pain and smoking (vs. nonsmokers without chronic pain) were more likely to report cocaine/crack and cannabis use, be prescribed long-term opioid therapy, and have virologic failure, even after controlling for relevant sociodemographic and substance-related variables (ps < .05). These results contribute to a growing empirical literature indicating that chronic pain and cigarette smoking frequently co-occur, and extend this work to a large sample of PLWH. Indeed, PLWH may benefit from interventions that are tailored to address bidirectional pain-smoking effects in the context of HIV.

Risk factors for postoperative eye pain in patients with non-painful eye disease undergoing pars plana vitrectomy: the VItrectomy Pain (VIP) study

BACKGROUND

Pars plana vitrectomy (PPV), a surgical procedure used to treat different ophthalmic pathologies, could be associated with moderate to severe eye pain. The aim of the present study was to evaluate the incidence of postoperative eye pain and its risk factors following PPV in a selected population of patients with non-painful eye disease, receiving regional anesthesia and moderate sedation with benzodiazepines, without use of narcotics.

METHODS

Single-center, prospective observational cohort study. We recorded the presence of pain at operating room discharge, at 6 and 24 hours, using the numeric rating scale (NRS). We recorded also age, sex, ethnic origin, American Society of Anaesthesia physical status (ASA PS) classification, Charlson Comorbidity Index, the etiology of the vitreoretinal pathology, length of surgery, and type of surgical procedure performed.

RESULTS

Eye pain (NRS>3) was present in three patients (0.7%) at operating room discharge, 59 (13.2%) at six and 65 (14.6%) at 24 hours after surgery. LASSO logistic regression analysis identified age, ASA PS, race, along with tamponade as independent risk factors for eye pain at six hours. Scleral buckling was selected for eye pain at 24 hrs.

CONCLUSIONS

A protocol for pain control after PPV should be considered, especially in younger, non-Caucasian people, and patients with high ASA PS grade. Moreover, attention must be paid when additional surgical procedures are requested, restricting them to selected patients, and using the appropriate agent for intraocular tamponade.