Physiological Measures of Acute and Chronic Pain within Different Subject Groups: A Systematic Review

Assessing pain in persons with opioid use disorder: Approaches, techniques and special considerations

Pain and opioid use disorder (OUD) are inextricably linked, as the former can be a risk factor for the development of the latter, and over a third of persons with OUD suffer concomitant chronic pain. Assessing pain among people with OUD is challenging, because ongoing opioid use brings changes in pain responses and most pain assessment tools have not been validated for this population. In this narrative review, we discuss the fundamentals of pain assessment for populations with OUD. First, we describe the biological, psychological and social aspects of the pain experience among people with OUD, as well as how opioid-related phenomena may contribute to the pain experience in this population. We then review methods to assess pain, including (1) traditional self-reported methods, such visual analogue scales and structured questionnaires; (2) behavioural observations and physiological indicators; (3) and laboratory-based approaches, such as quantitative sensory testing. These methods are considered from a perspective that encompasses both pain and OUD. Finally, we discuss strategies for improving pain assessment in persons with OUD and implications for future research, including educational strategies for multidisciplinary teams. We highlight the substantial gaps that persist in this literature, particularly regarding the applicability of current pain assessment methods to persons with OUD, as well as the generalizability of the existing results from adjacent populations on chronic opioid therapy but without OUD. As research linking pain and OUD evolves, considering the needs of diverse populations with complex psychosocial backgrounds, clinicians will be better equipped to reduce these gaps.

Clinical efficacy and patients' perception of virtual reality during wound care in adults: A systematic review with meta-analysis of randomised clinical trials

This study was aimed to review Virtual Reality's (VR) impact on pain, anxiety, opioid usage, physiological and behavioural responses, and patients' experience during wound care (WC) in adults. We searched multiple databases (Embase, Medline ALL, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, CINAHL, Scopus and Google Scholar) from inception until January 27th, 2023. Included studies compared VR alone or as an adjunct to standard WC with standard WC or other distraction methods, in adults with burn or non-burn-related wounds. The risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomised parallel-group and crossover trials. The review followed PRISMA guidelines for reporting. Fourteen studies were eligible for inclusion. The meta-analysis was limited to studies comprising solely of adult participants. VR reduced pain intensity compared to standard WC in all study designs. Despite not being included in the meta-analysis due to reasons such as mixed population or lack of sufficient statistical data, other studies showed significant pain reduction using VR. Additionally, VR improved patients' experience of WC. No clear effect was found on other outcomes including anxiety, opioid usage and physiological and behavioural responses. VR shows promise in reducing acute pain and enhancing patients' experience of WC. The observed variations in the effects of VR at group and individual levels indicate the need for a personalised treatment plan by selecting the right VR for the right patient given at the right time.

The efficacy of manual therapy on HRV in those with long-standing neck pain: a systematic review

OBJECTIVES

Long-standing neck pain (LNP) is a clinical condition frequently encountered in the physical therapy clinic. LNP is a complex, multifactorial condition affecting multiple body systems including the autonomic nervous system (ANS). Traditionally, research on the impact of physical therapy on LNP has focused on self-report measures and pain scales. Heart rate variability (HRV) is an objective measure of the ANS, allowing for quantification of effects of treatment. This systematic review is intended to evaluate if manual therapy acutely affects heart rate variability in adults with long-standing neck pain.

METHODS

Pubmed, Medline, CINAHL, Google Scholar, Web of Science, and Cochrane library were used to retrieve the randomized controlled trials for this review between the years 2010-2021. Search terms included: chronic neck pain, neck pain, cervical pain, manual therapy, mobilization, manipulation, osteopathy, osteopathic or chiropractic. Heart rate variability, HRV, heart rate variation, effects, outcomes, benefits, impacts or effectiveness.

RESULTS

Of 139 articles located and screened, three full-text articles were selected for full qualitative synthesis, with a combined population of 112 subjects, 91 of which were female, with an average age of 33.7 ± 6.8 years for all subjects. MT techniques in three studies were statistically significant in improving HRV in people with LNP; however, techniques were differed across studies, while one study showed no benefit. The studies were found to be of high quality with PEDro scores ≥6.

CONCLUSIONS

Although no clear cause and effect relationship can be established between improvement in HRV with manual therapy, results supported the use of MT for an acute reduction in HRV. No one particular method of MT has proven superior, MT has been found to produce a statistically significant change in HRV. These HRV changes are consistent with decreased sympathetic tone and subjective pain.

Artificial Intelligence for Automatic Pain Assessment: Research Methods and Perspectives

Although proper pain evaluation is mandatory for establishing the appropriate therapy, self-reported pain level assessment has several limitations. Data-driven artificial intelligence (AI) methods can be employed for research on automatic pain assessment (APA). The goal is the development of objective, standardized, and generalizable instruments useful for pain assessment in different clinical contexts. The purpose of this article is to discuss the state of the art of research and perspectives on APA applications in both research and clinical scenarios. Principles of AI functioning will be addressed. For narrative purposes, AI-based methods are grouped into behavioral-based approaches and neurophysiology-based pain detection methods. Since pain is generally accompanied by spontaneous facial behaviors, several approaches for APA are based on image classification and feature extraction. Language features through natural language strategies, body postures, and respiratory-derived elements are other investigated behavioral-based approaches. Neurophysiology-based pain detection is obtained through electroencephalography, electromyography, electrodermal activity, and other biosignals. Recent approaches involve multimode strategies by combining behaviors with neurophysiological findings. Concerning methods, early studies were conducted by machine learning algorithms such as support vector machine, decision tree, and random forest classifiers. More recently, artificial neural networks such as convolutional and recurrent neural network algorithms are implemented, even in combination. Collaboration programs involving clinicians and computer scientists must be aimed at structuring and processing robust datasets that can be used in various settings, from acute to different chronic pain conditions. Finally, it is crucial to apply the concepts of explainability and ethics when examining AI applications for pain research and management.

A systematic review of neurophysiological sensing for the assessment of acute pain

Pain is a complex and personal experience that presents diverse measurement challenges. Different sensing technologies can be used as a surrogate measure of pain to overcome these challenges. The objective of this review is to summarise and synthesise the published literature to: (a) identify relevant non-invasive physiological sensing technologies that can be used for the assessment of human pain, (b) describe the analytical tools used in artificial intelligence (AI) to decode pain data collected from sensing technologies, and (c) describe the main implications in the application of these technologies. A literature search was conducted in July 2022 to query PubMed, Web of Sciences, and Scopus. Papers published between January 2013 and July 2022 are considered. Forty-eight studies are included in this literature review. Two main sensing technologies (neurological and physiological) are identified in the literature. The sensing technologies and their modality (unimodal or multimodal) are presented. The literature provided numerous examples of how different analytical tools in AI have been applied to decode pain. This review identifies different non-invasive sensing technologies, their analytical tools, and the implications for their use. There are significant opportunities to leverage multimodal sensing and deep learning to improve accuracy of pain monitoring systems. This review also identifies the need for analyses and datasets that explore the inclusion of neural and physiological information together. Finally, challenges and opportunities for designing better systems for pain assessment are also presented.

Pain Recognition in Ferrets

Recognition and accurate assessment of the severity of pain can be challenging in ferrets as they are unable to verbally communicate, and often hide their pain. Pain assessment relies on the assessment of behavioral, physiologic, and other clinical parameters that serve as indirect indicators of pain. Assessment of physiologic and clinical parameters requires handling, which results in changes in these parameters. Behavioral parameters can be assessed less invasively by observing the patient. Due to their nonspecificity, correct interpretation may be challenging. Just as in other species, a grimace scale seems to be the most helpful tool in recognizing pain in ferrets.

A Systematic Review of Virtual Reality Therapeutics for Acute Pain Management

OBJECTIVES

The purpose of this systematic review is to examine the delivery and clinical efficacy of virtual reality (VR) therapeutics for acute pain management in adults and identify practical considerations of VR deployment, as well as current gaps in the literature.

DESIGN

A systematic review.

DATA SOURCES

A search of PubMed, CINAHL, PsychINFO, Embase, Compendex, and Inspec was completed using Medical Subject Headings (MeSH) and keyword search terms related to acute pain and VR.

REVIEW/ANALYSIS METHODS

A systematic review of all pertinent articles published between January 1, 2000, and August 1, 2020, was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines.

RESULTS

Twenty-three articles met final inclusion criteria and were included in this review. Studies utilized VR in a variety of settings for wound care, procedure-induced pain, physical or occupational therapy, dental treatment or generalized acute pain. A likely mechanism by which VR promoted analgesia in these studies is distraction. Of the reviewed studies, 19 (83%) reported decreases in pain intensity while using VR compared with no VR use or with a non-VR group.

CONCLUSIONS

This systematic review found VR to be an effective tool for acute pain management. Findings from this review also underscore the importance of addressing the patient's sense of presence and levels of immersion, interaction, and interest when deploying VR. Future VR studies should consider incorporation of anxiety, presence, and VR side effect measures in addition to acute pain metrics.

The Current View on the Paradox of Pain in Autism Spectrum Disorders

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, which affects 1 in 44 children and may cause severe disabilities. Besides socio-communicational difficulties and repetitive behaviors, ASD also presents as atypical sensorimotor function and pain reactivity. While chronic pain is a frequent co-morbidity in autism, pain management in this population is often insufficient because of difficulties in pain evaluation, worsening their prognosis and perhaps driving higher mortality rates. Previous observations have tended to oversimplify the experience of pain in autism as being insensitive to painful stimuli. Various findings in the past 15 years have challenged and complicated this dogma. However, a relatively small number of studies investigates the physiological correlates of pain reactivity in ASD. We explore the possibility that atypical pain perception in people with ASD is mediated by alterations in pain perception, transmission, expression and modulation, and through interactions between these processes. These complex interactions may account for the great variability and sometimes contradictory findings from the studies. A growing body of evidence is challenging the idea of alterations in pain processing in ASD due to a single factor, and calls for an integrative view. We propose a model of the pain cycle that includes the interplay between the molecular and neurophysiological pathways of pain processing and it conscious appraisal that may interfere with pain reactivity and coping in autism. The role of social factors in pain-induced response is also discussed. Pain assessment in clinical care is mostly based on subjective rather than objective measures. This review clarifies the strong need for a consistent methodology, and describes innovative tools to cope with the heterogeneity of pain expression in ASD, enabling individualized assessment. Multiple measures, including self-reporting, informant reporting, clinician-assessed, and purely physiological metrics may provide more consistent results. An integrative view on the regulation of the pain cycle offers a more robust framework to characterize the experience of pain in autism.

Chronic neuropathic pain is more than a perception: Systems and methods for an integral characterization

The management of chronic neuropathic pain remains a challenge, because pain is subjective, and measuring it objectively is usually out of question. However, neuropathic pain is also a signal provided by maladaptive neuronal activity. Thus, the integral management of chronic neuropathic pain should not only rely on the subjective perception of the patient, but also on objective data that measures the evolution of neuronal activity. We will discuss different objective and subjective methods for the characterization of neuropathic pain. Additionally, the gaps and proposals for an integral management of chronic neuropathic pain will also be discussed. The current management that relies mostly on subjective measures has not been sufficient, therefore, this has hindered advances in pain management and clinical trials. If an integral characterization is achieved, clinical management and stratification for clinical trials could be based on both questionnaires and neuronal activity. Appropriate characterization may lead to an increased effectiveness for new therapies, and a better quality of life for neuropathic pain sufferers.

Nurses' Perceived Barriers to and Facilitators of Pain Assessment and Management in Critical Care Patients: A Systematic Review

Aim

This review aims to examine nurses’ perceived barriers to and facilitators of pain assessment and management in adult critical care patients.

Background

Pain is one of the worst memories among critically ill patients. However, pain among those patients is still undertreated due to several barriers that impede effective management. Therefore, addressing the perceived barriers and facilitators to pain assessment management among critical care nurses is crucial.

Methods

A systematic search of pain assessment and management in critical care patient-relevant literature from four databases was done, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Results

The barriers and facilitators were categorized into four groups: nurse-related, patient-related, physician-related, and system-related. The most frequently reported barriers in this study included nurses’ lack of knowledge regarding the use of pain assessment tools, patients’ inability to communicate, physicians’ prescription of analgesics being independent of pain scores evaluation, and absence of standardized guidelines and protocols for pain evaluation and control. For the facilitators, the most reported ones include ongoing education and professional training related to pain assessment and management, patients’ ability to self-report pain, effective collaboration between physicians and nurses, and productive discussion of patients’ pain scores during nurse-to-nurse handovers.

Conclusion

Various barriers and facilitators to pain assessment and management were identified and examined in this review. However, future research is still needed to further investigate these barriers and facilitators and examine any other potential associated factors among critical care nurses.

Relevance to Clinical Practice

The findings of our study could help hospital managers in developing continuous education and staff development training programs on assessing and managing pain for critical care patients. Also, our findings could be used to develop an evidence-based standard pain management protocol tailored to effectively assess and promptly treat pain in critical care patients.