Chronic Pain: A Complex Condition With a Multi-Tangential Approach

Neurosurgical management for chronic and end-of-life pain in children: A systematic review

INTRODUCTION

Chronic and end-of-life pain in children is underreported and undermanaged. Current guidelines for pediatric chronic pain include medical and interventional modalities; however, the inclusion of neurosurgical treatments is uncommon and inconsistent. This systematic review presents the literature, and we provide recommendations for the role of neurosurgical procedures in treating chronic and end-of-life pain in children.

METHODS

A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines using three databases: PubMed, Embase, and Scopus. We included 40 studies presenting neurosurgical procedures for the treatment of chronic and end-of-life pain in children.

RESULTS

Thirty-one (77.5%) manuscripts focused on the treatment of neuropathic pain, five (12.5%) focused on nociceptive pain, and four (10%) treated mixed pain conditions. The most common neurosurgical procedure was intrathecal opioid therapy via pump placement (29.3%), followed by spinal cord stimulation (26.8%). Neuropathic pain syndromes were primarily treated with neurostimulation (58%), demonstrating good efficacy. Ablative procedures (40%) were most effective for nociceptive pain syndromes. Both chordotomy and intrathecal pumps provided subjective pain relief for mixed pain syndromes. The quantification of procedural efficacy, including pain outcomes and grading scales, varied significantly across studies.

CONCLUSION

Neurosurgical treatments for chronic pediatric pain are safe, although broad efficacy cannot be determined due to sparse literature and inadequately quantified pain responses. Guidelines for escalating chronic and end-of-life pain management in pediatric patients should be updated to include neurosurgical treatments and appropriate outcome scales. Focused research on appropriate patients, available neurosurgical therapies, and pediatric outcomes is warranted.

Comparing Maintenance Therapy Achievement for Opioid-Experienced Patients Converted to Buprenorphine for Chronic Pain Management

Treatment of chronic, non-cancer pain can be challenging in the presence of long-term opioid therapy (LTOT). Buprenorphine products can provide a unique option for chronic pain treatment due to the improved safety profile with a ceiling effect on respiratory depression. Drug manufacturers provide recommendations for conversion from full mu agonist to buprenorphine which typically includes tapering to lower morphine equivalent doses (MEDD). This study will attempt to compare if there is a difference in the ability of achieving buprenorphine maintenance therapy for chronic pain based on the starting opioid MEDD. This study's primary endpoint is the difference in ability to achieve buprenorphine maintenance therapy for chronic, non-cancer pain based on baseline MEDD (i.e., ≤30 MEDD vs >30 MEDD). Secondary endpoints will describe method of conversion to buprenorphine, difference in frequency of follow up and average time to achieve maintenance doses. There was no difference in ability to achieve buprenorphine maintenance doses between either group. Approximately 40% of patients in each group achieved maintenance doses regardless of baseline MEDD. Patients on higher MEDDs had the same likelihood of achieving buprenorphine maintenance therapy for chronic pain as those were at 30 MEDD and can be considered for buprenorphine therapy without tapering first.

A cutting-edge new framework for the pain management in children: nanotechnology

Pain is a subjective concept which is ever-present in the medical field. Health professionals are confronted with a variety of pain types and sources, as well as the challenge of managing a patient with acute or chronic suffering. An even bigger challenge is presented in the pediatric population, which often cannot quantify pain in a numerical scale like adults. Infants and small children especially show their discomfort through behavioral and physiological indicators, leaving the health provider with the task of rating the pain. Depending on the pathophysiology of it, pain can be classified as neuropathic or nociceptive, with the first being defined by an irregular signal processing in the nervous system and the second appearing in cases of direct tissue damage or prolonged contact with a certain stimulant. The approach is generally either pharmacological or non-pharmacological and it can vary from using NSAIDs, local anesthetics, opiates to physical and psychological routes. Unfortunately, some pathologies involve either intense or chronic pain that cannot be managed with traditional methods. Recent studies have involved nanoparticles with special characteristics such as small dimension and large surface area that can facilitate carrying treatments to tissues and even offer intrinsic analgesic properties. Pediatrics has benefited significantly from the application of nanotechnology, which has enabled the development of novel strategies for drug delivery, disease diagnosis, and tissue engineering. This narrative review aims to evaluate the role of nanotechnology in current pain therapy, with emphasis on pain in children.

Adolescent morphine exposure changes the endogenous vlPAG opioid response to inflammatory pain in rats

Adolescence is one of the most critical periods for brain development, and exposure to morphine during this period can have long-life effects on pain-related behaviors. The opioid system in the periaqueductal gray (PAG) is highly vulnerable to drug exposure. However, the impact of adolescent morphine exposure (AME) on the endogenous opioid system in the PAG is currently unknown. This study aims to investigate the long-lasting effects of AME on the endogenous opioid system and its involvement in altering nociceptive behaviors. Adolescent rats were given escalating doses of morphine (2.5-25 mg/kg, subcutaneous) or an equal volume of saline twice daily for 10 consecutive days (PND 31-40). After a 30-day washout period, adult rats underwent formalin tests following microinjection of morphine, naloxone, or saline into the ventrolateral PAG (vlPAG) region. The results indicated that morphine microinjection into the vlPAG of the adolescent morphine-treated group significantly reduced the nociceptive score. However, the analgesic response to morphine in this group was significantly lower compared to the saline-treated group during adolescence. Additionally, the nociceptive score significantly increased following naloxone but not saline microinjection into the vlPAG of the saline-treated group during adolescence, rather than the morphine-treated one. These findings indicate that AME has long-lasting effects on the endogenous opioid system in the vlPAG, which can consequently alter behaviors related to inflammatory pain in adulthood.

Targeting the Main Sources of Reactive Oxygen Species Production: Possible Therapeutic Implications in Chronic Pain

Humans have long been combating chronic pain. In clinical practice, opioids are firstchoice analgesics, but long-term use of these drugs can lead to serious adverse reactions. Finding new, safe and effective pain relievers that are useful treatments for chronic pain is an urgent medical need. Based on accumulating evidence from numerous studies, excess reactive oxygen species (ROS) contribute to the development and maintenance of chronic pain. Some antioxidants are potentially beneficial analgesics in the clinic, but ROS-dependent pathways are completely inhibited only by scavenging ROS directly targeting cellular or subcellular sites. Unfortunately, current antioxidant treatments do not achieve this effect. Furthermore, some antioxidants interfere with physiological redox signaling pathways and fail to reverse oxidative damage. Therefore, the key upstream processes and mechanisms of ROS production that lead to chronic pain in vivo must be identified to discover potential therapeutic targets related to the pathways that control ROS production in vivo. In this review, we summarize the sites and pathways involved in analgesia based on the three main mechanisms by which ROS are generated in vivo, discuss the preclinical evidence for the therapeutic potential of targeting these pathways in chronic pain, note the shortcomings of current research and highlight possible future research directions to provide new targets and evidence for the development of clinical analgesics.

Using a multimodal approach to manage difficult visceral cancer pain: A case study

Difficult visceral cancer pain is defined as pain that does not improve with conventional non-pharmacological and pharmacological strategies, including opioids and adjuvants, and occurs in up to 15% of patients with cancer. In oncological practice, we must be prepared to establish strategies for dealing with such complex cases. Different analgesic strategies have been described in the literature, including managing refractory pain through palliative sedation; however, this might become a dilemma from a clinical and bioethical point of view in end-of-life situations. We present the case of a young male patient with moderately differentiated intestinal-type adenocarcinoma of the left colon, with intra-abdominal sepsis, and for whom despite the multimodal treatment for difficult visceral cancer pain, the pain was refractory leading to palliative sedation. Difficult visceral cancer pain is a pathology that affects the quality of life of patients and is a challenge for pain specialists, for both pharmacological and non-pharmacological management.