Chronic pain is a debilitating condition that affects millions of patients worldwide, contributing to a high disease burden and millions of dollars in lost wages, missed workdays, and healthcare costs. Opioids, NSAIDs, acetaminophen, gabapentinoids, muscle relaxants, anticonvulsants, and antidepressants are the most used medications for chronic pain and carry significant side effects, including gastric bleeding, hepatotoxicity, stroke, kidney damage, constipation, dizziness, and arrhythmias. Opioids in particular carry the risk of long-term dependence, drug tolerance, and overdose. In 2022, 81,806 people died from opioid overdose in the United States alone. Alternative treatments for chronic pain are critically needed, and nanotechnology has emerged as a promising means of achieving effective long-term analgesia while avoiding the adverse side effects associated with conventional pharmacological agents. Nanotechnology-based treatments include liposomes, Poly Lactic-co-Glycolic Acid (PLGA) and other polymeric nanoparticles, and carbon-based polymers, which can help mitigate those adverse side effects. These nanomaterials can serve as drug delivery systems that facilitate controlled release and drug stability via the encapsulation of free molecules and protein-based drugs, leading to longer-lasting analgesia and minimizing side effects. In this review, we examine the role of nanotechnology in addressing concerns associated with conventional chronic pain treatments and discuss the ongoing efforts to develop novel, nanotechnology-based treatments for chronic pain such as nanocapacitor patches, gene therapy, the use of both viral and non-viral vectors, CRISPR, and scavengers.

Careful perioperative pain management is crucial for good patient outcomes after surgery, as poorly controlled pain interferes with the ability of patients to recover to normal baseline function and increases postoperative morbidity and mortality. Although opioids have been the mainstay for treating postoperative pain, there has been a shift in favor of a multimodal analgesic approach, including regional anesthesia, as a way to circumvent opioid-related adverse events (e.g. nausea and vomiting, respiratory depression, sedation). In this chapter, we present an update on several recently developed regional anesthetic techniques, local anesthetic medications, as well as nerve block adjuncts with the potential to improve pain management in the perioperative setting. With more future studies, these novel methods may be incorporated into postsurgical recovery protocols and provide the opportunity to improve patient outcomes.

The prevalence of patients on buprenorphine therapy presenting for elective surgery has increased. Buprenorphine is a widely used medication for the management of patients with chronic pain. It is also used as maintenance therapy for patients with a history of opioid use disorder (OUD). Due to the lack of a standardized protocol for managing patients on buprenorphine perioperatively, we performed a retrospective analysis to compare pain score outcomes and postoperative opiate requirements between patients who continued buprenorphine versus patients who discontinued buprenorphine. We identified 35 patients: 11 continued buprenorphine and 24 discontinued buprenorphine. The average Post-Anesthesia Care Unit (PACU) pain score was 5.59 for those who continued buprenorphine and 7.54 for those who discontinued preoperative buprenorphine (p value 0.0339). The average postoperative morphine milligram equivalent (MME) use was 86.13 for those who continued preoperative buprenorphine and 107.70 for those who discontinued buprenorphine (p value 0.6439). The results from our study correlate with several previous studies, which showed lower PACU pain scores in patients who continued buprenorphine. There is a benefit of decreased postoperative pain when preoperative buprenorphine is continued, and a decreased possibility for relapse in those with a history of OUD.

Neuropathic pain has emerged as a significant concern for patients dealing with persistent post-COVID-19 symptoms. Small fiber neuropathy (SFN) has been identified as a potential underlying mechanism contributing to long-term pain in these patients. Despite an increasing body of evidence associating post-COVID-19 SFN with immune dysregulation and neuroinflammation, the exact pathophysiology and optimal treatment remains unclear. This review aims to explore the pathophysiology, diagnosis, proposed mechanisms, and treatment of post-COVID-19 SFN. A comprehensive literature review was conducted, examining studies on SFN, as well as SFN in the context of COVID-19, including clinical manifestations, diagnostic criteria, and potential treatment modalities. Evidence was gathered from case studies, observational reports, and clinical trials addressing post-COVID-19 neuropathy and SFN. SFN in long COVID presents a heterogeneous range of sensory and autonomic symptoms. Diagnosis relies on clinical evaluation, quantitative sensory testing, and confirmatory skin biopsy. Proposed mechanisms include autoimmune dysregulation, molecular mimicry, direct viral invasion of neural structures, and inflammatory responses. Pharmacological treatments—such as gabapentin, antidepressants, and corticosteroids—have demonstrated symptom relief, while immunomodulatory therapies show promise in immune-mediated cases. Non-pharmacological strategies warrant further investigation. Post-COVID-19 SFN represents a complex and multifactorial condition requiring a multidisciplinary approach to diagnosis and management. While merging evidence supports immune-mediated pathogenesis, further research is needed to establish definitive mechanisms and optimize targeted therapeutic strategies. Continued investigation into post-COVID-19 SFN will be crucial in addressing the long-term neurological sequelae of SARS-CoV-2 infection.

The prevalence of patients on buprenorphine therapy presenting for elective surgery has increased. Buprenorphine is a widely used medication for management of patients with chronic pain. It is also used for maintenance therapy for patients with a history of opioid use disorder (OUD). Due to lack of standardized protocol for managing patients on buprenorphine peri-operatively, we performed a retrospective analysis to compare pain score outcomes and post-operative opiate requirements between patients who continued versus discontinued buprenorphine. We identified 35 patients, 11 continued buprenorphine and 24 discontinued buprenorphine. The average Post-Anesthesia Care Unit (PACU) pain score was 7.54 for those who discontinued pre-operative buprenorphine and 5.59 for those who continued (P value 0.0339). The average post-operative Morphine Milligram Equivalent (MME) use was 86.13 for those who continued pre-operative buprenorphine and was 107.70 for those who discontinued buprenorphine (P value 0.6439). The results from our study correlate with several previous studies which showed lower PACU pain scores in patients who continued buprenorphine. There is a benefit of decreased pain post-operatively when pre-operative buprenorphine is continued and having a decrease in relapse in those with a history of OUD.