Tertiary Care Clinical Experience with Intravenous Lidocaine Infusions for the Treatment of Chronic Pain.

Objective: To evaluate the safety of and long-term pain relief due to intravenous lidocaine infusion for the treatment of chronic pain in a tertiary pain management clinic. Design: Retrospective chart review. Methods: Medical records were reviewed from 233 adult chronic pain patients who underwent one to three lidocaine infusions. The initial lidocaine challenge consisted of 1,000 mg/h administered intravenously for up to 30 minutes until infusion was complete, full pain resolution, the patient requested to stop, side effects (SEs) became intolerable, and/or if there were any safety concerns. Subsequent infusions were tailored to patient response. Data reviewed included pain diagnosis, lidocaine dose, SEs, and duration of pain relief documented at a follow-up visit. Results: Patients primarily had neuropathic pain (80%), were 94% white, 58% were female, and there was an average pain duration of 7.9 years. SEs were usually mild and transient, including perioral tingling, dizziness, tinnitus, and nausea/vomiting, and they were uncommon after the initial infusion. Overall, 41% of patients showed long-lasting pain relief, with positive response to the initial infusion associated with receiving and benefitting from subsequent infusions. Benefit by pain diagnoses varied from 32% to 58%. Conclusions: Our retrospective study in a heterogeneous population with chronic pain suggests that intravenous lidocaine is a safe treatment. Data also suggest long-term pain relief in a significant proportion of patients. Additional study is important in order to delineate patient selection, determine optimal dosing and treatment frequency, assess pain reduction and duration, and treatment cost-effectiveness.

Do sleep disorders contribute to pain sensitivity?

Sleep disturbance is one of the most common comorbid problems for chronic pain patients. The association between the two phenomena has long been recognized, but the nature of the relationship is not well-understood. Many agree that the relationship is likely bidirectional. In this review, we focus on one side of the relationship: whether and how disordered sleep adversely impacts pain. We discuss the available evidence from the epidemiologic, clinical, and human, as well as infrahuman laboratory studies. Generally, the literature supports the positive relationship between poor sleep and increased pain. Sleep deprivation also seems to attenuate analgesic effects of medications. Research delineating the causal or associative relationship between sleep and pain is still preliminary at this time. Continuing efforts in both experimental and clinical research are needed to develop a translationally meaningful understanding of how poor sleep impacts pain.

Management of fibromyalgia syndrome in 2016.

Fibromyalgia syndrome is a chronic pain disorder and defies definitively efficacious therapy. In this review, we summarize the results from the early treatment research as well as recent research evaluating the pharmacological, interventional and nonpharmacological therapies. We further discuss future directions of fibromyalgia syndrome management; we specifically focus on the issues that are associated with currently available treatments, such as the need for personalized approach, new technologically oriented and interventional treatments, the importance of understanding and harnessing placebo effects and enhancement of patient engagement in therapy.

The association between chronic pain and obesity.

Obesity and pain present serious public health concerns in our society. Evidence strongly suggests that comorbid obesity is common in chronic pain conditions, and pain complaints are common in obese individuals. In this paper, we review the association between obesity and pain in the general population as well as chronic pain patients. We also review the relationship between obesity and pain response to noxious stimulation in animals and humans. Based upon the existing research, we present several potential mechanisms that may link the two phenomena, including mechanical/structural factors, chemical mediators, depression, sleep, and lifestyle. We discuss the clinical implications of obesity and pain, focusing on the effect of weight loss, both surgical and noninvasive, on pain. The literature suggests that the two conditions are significant comorbidities, adversely impacting each other. The nature of the relationship however is not likely to be direct, but many interacting factors appear to contribute. Weight loss for obese pain patients appears to be an important aspect of overall pain rehabilitation, although more efforts are needed to determine strategies to maintain long-term benefit.

Relationship between psychopathology and graduated spinal block findings in chronic pain patients.

The current study was undertaken to investigate the relationship between response to a graduated spinal block and the presence of psychopathology. Subjects consisted of 25 chronic pain patients who had received a graduated spinal block as part of their evaluation. Each was categorized along two dimensions by independent raters based on blind review of hospital records. Dimensions were (1) response to graduated spinal block (appropriate or inappropriate) and (2) presence of clinically significant psychopathology (definitive, probable or none). Results showed that subjects were well distributed across the two dimensions. A 2 X 3 chi-square comparison failed to show a significant relationship between the two dimensions. However, females and subjects with spontaneous pain onset were found to exhibit significantly more inappropriate responses to spinal blockage. It was concluded that there was no consistent relationship between the presence of psychopathology and response to the graduated spinal block.

Management of fibromyalgia syndrome: review of evidence.

Fibromyalgia syndrome (FMS) is a common chronic musculoskeletal pain disorder of unknown etiology and characterized by generalized body pain, hyperalgesia, and other functional and emotional comorbidities. Despite extensive research, no treatment modality is effective for all FMS patients. In this paper, we briefly review the history of FMS and diagnostic criteria, and potential pathophysiological mechanisms including central pain modulation, neurotransmitters, sympatho-adrenal and hypothalamic-pituitary-adrenal systems and peripheral muscle issues. The primary focus of the paper is to review treatment options for managing fibromyalgia symptoms. We will discuss FDA-approved medications and other pharmacologic agents, and non-pharmacologic treatments that have shown promising effects.

Nightly analyses of subjective and objective (actigraphy) measures of sleep in fibromyalgia syndrome: what accounts for the discrepancy?

OBJECTIVES: To evaluate the concordance between the subjective and objective methods of sleep assessment in patients with fibromyalgia syndrome (FMS) and to delineate factors associated with discrepancy between the 2 sleep assessment methods. METHODS: Seventy-five patients with FMS completed a 7-day home assessment protocol. They wore an actigraphic device at all times. In the morning, they used the electronic diary to record the subjective report of sleep from the previous night and current severity of the FMS-related symptoms. RESULTS: On average, the 2 assessment methods yielded a 73 absolute minute difference per night per patient. About half of the nights, sleep duration was underestimated. Approximately 20% of the nights had greater than 2-hour difference between the 2 methods. Factors related to this large discrepancy were (1) objective indicator of restless sleep, (2) subjective report of difficulty falling asleep, and (3) report of fatigue at the time of reporting. FMS-related symptoms were related to subjective report of poor sleep but not to objective sleep data. DISCUSSION: Misestimation of sleep seems common in FMS patients, particularly when their sleep quality is poor. Careful considerations for evaluating the severity of patients' sleep complaints are critical in adequate management of sleep disturbance that is commonly reported by FMS patients.