A brief review of complex regional pain syndrome and current management

Complex regional pain syndrome (CRPS) is a debilitating chronic pain condition that, although exceedingly rare, carries a significant burden for the affected patient population. The complex and ambiguous pathophysiology of this condition further complicates clinical management and therapeutic interventions. Furthermore, being a diagnosis of exclusion requires a diligent workup to ensure an accurate diagnosis and subsequent targeted management. The development of the Budapest diagnostic criteria helped to consolidate existing definitions of CRPS but extensive work remains in identifying the underlying pathways. Currently, two distinct types are identified by the presence (CRPS type 1) or absence (CRPS type 2) of neuronal injury. Current management directed at this disease is broad and growing, ranging from non-invasive modalities such as physical and psychological therapy to more invasive techniques such as dorsal root ganglion stimulation and potentially amputation. Ideal therapeutic interventions are multimodal in nature to address the likely multifactorial pathological development of CRPS. Regardless, a significant need remains for continued studies to elucidate the pathways involved in developing CRPS as well as more robust clinical trials for various treatment modalities.

A Case Report of Acute Onset and Rapid Resolution of Atrioventricular Block After Sugammadex: Is the Autonomic System Involved?

Administering sugammadex to reverse neuromuscular blockade can cause marked bradycardia and rarely asystole. In this case, a rapid onset, biphasic heart rate response; slowing then speeding, after administering sugammadex was noted while at steady state, 1.3% end-tidal sevoflurane. On review of the electrocardiogram (ECG), the heart rate slowing coincided with the onset of a second-degree, Mobitz type I block that lasted 45 seconds. No other events, drugs, or stimuli coincided with the event. The acute onset and transient nature of the atrioventricular block without evidence of ischemia implies a brief parasympathetic effect on the atrioventricular node after sugammadex administration.

A Review of Chronic Pain and Device Interventions: Benefits and Future Directions

Chronic pain is a debilitating condition with a growing prevalence both in the USA and globally. The complex nature of this condition necessitates a multimodal approach to pain management that extends beyond the established pharmaceutical interventions currently employed. A variety of devices comprising both invasive and noninvasive approaches are available to patients, serving as adjuvants to existing regimens. The benefits of these interventions are notable for their lack of addiction potential, potential for patient autonomy regarding self-administration, minimal to no drug interaction, and overall relative safety. However, there remains a need for further research and more robust clinical trials to assess the true efficacy of these interventions and elucidate if there is an underlying physiological mechanism to their benefit in treating chronic pain or if their effect is predominantly placebo in nature. Regardless, the field of device-based intervention and treatment remains an evolving field with much promise for the future chronic pain management.

Eptinezumab-jjmr, a humanized monoclonal specific to Calcitonin Gene Related Peptide, for the preventive treatment of migraine in adults

Purpose of Review

Migraines are prevalent and cause significant morbidity, decline in quality of life and healthcare costs universally. Treatment options are varied, but efficacy is limited. This review centers on Eptinezumab-jjmr, a humanized monoclonal specific to CGRP for the prevention of migraines in adults. Herein presented are the science and mechanism of action, indication and clinical evidence for use.

Recent Findings

Migraines are severe, recurrent headaches, which are either episodic or chronic in nature. The pain is severe, often accompanied by co-morbid symptoms, such as photophobia, phonophobia, nausea and emesis, and is limiting in nature. It is a prevalent disorder that causes significant, worldwide disability, morbidity, suffering, and costs.

The pathophysiology of migraines is actively studied, though recent research points to an initiating event causing migraine generation, that is then propagated by other brain regions, a significant one being the trigeminocervical complex. This is driven by biochemical transmitters, chiefly CGRP. This discovery led to the development of CGRP-targeting drugs, including gepants (small molecular antagonists) and anti-CGRP antibodies, such as Eptinezumab-jjmr.

Traditional therapy includes preventative and abortive treatment; however, adherence with preventative treatment has been historically poor, and certain types of abortive therapy carry risks and side effects that preclude them from a large patient population. Moreover, traditional therapy often falls short in migraine therapy. CGRP antagonist, including Eptinezumab, aims to cover the gaps in migraine therapy. We present here evidence to support the safe and effective use of Eptinezumab for the prevention of migraines.

Summary

Migraines are a prevalent primary headache disorder causing significant morbidity worldwide. Traditional abortive and preventative treatments fall short for many patients. Eptinezumab is part of new generation of CGRP-targeting medications and has shown significant evidence to support its use for the prevention of migraines. Further research is required to properly compare eptinezumab with existing pharmacotherapy and update guidelines on the appropriate combinations of therapies that are not available and the correct patient selection for each.

Clinically Relevant Drug Interactions with Monoamine Oxidase Inhibitors

Monoamine oxidase inhibitors (MAOI) are a class of drugs that were originally developed for the treatment of depression but have since been expanded to be used in management of affective and neurological disorders, as well as stroke and aging-related neurocognitive changes. Ranging from irreversible to reversible and selective to non-selective, these drugs target the monoamine oxidase (MAO) enzyme and prevent the oxidative deamination of various monoamines and catecholamines such as serotonin and dopamine, respectively. Tyramine is a potent releaser of norepinephrine (NE) and is found in high concentrations in foods such as aged cheeses and meats. Under normal conditions, NE is unable to accumulate to toxic levels due to the presence of MAO-A, an enzyme that degrades neurotransmitters, including NE. When MAO-A is inhibited, the capacity to handle tyramine intake from the diet is significantly reduced causing the brain to be vulnerable to overstimulation of postsynaptic adrenergic receptors with as little as 8-10 mg of tyramine ingested and can result in life-threatening blood pressure elevations. In addition to adverse reactions with certain foods, both older and newer MAOIs can negatively interact with both sympathomimetic and serotonergic drugs. In general, patients on a MAOI want to avoid two types of medications: those that can elevate blood pressure via sympathomimetic actions (e.g., phenylephrine and oxymetazoline) and those that can increase serotonin levels via 5-HT reuptake inhibition (e.g., dextromethorphan, chlorpheniramine, and brompheniramine). Illicit drugs that stimulate the central nervous system such as ecstasy (MDMA, 3,4-methylenedioxymethamphetamine) act as serotonin releasers. Patient involvement is also crucial to ensure any interaction within the healthcare setting includes making other providers aware of a MAOI prescription as well as avoiding certain OTC medications that can interact adversely with MAOIs.

Buprenorphine and its formulations: a comprehensive review

Buprenorphine, a novel long-acting analgesic, was developed with the intention of two purposes: analgesia and opioid use disorder. Regarding its pharmacodynamics, it is a partial agonist at mu receptors, an inverse agonist at kappa receptors, and an antagonist at delta receptors. For the purpose of analgesia, three formulations of buprenorphine were developed: IV/IM injectable formulation (Buprenex®), transdermal patch formulation (Butrans®), and buccal film formulation (Belbuca®). Related to opioid dependence, the formulations developed were subcutaneous extended release (Sublocade®), subdermal implant (Probuphine®), and sublingual tablets (Subutex®). Lastly, in order to avoid misuse of buprenorphine for opioid dependence, two combination formulations paired with naloxone were developed: film formulation (Suboxone®) and tablet formulation (Zubsolv®). In this review, we present details of each formulation along with their similarities and differences between each other and clinical considerations.

Preoperative laboratory testing: Implications of "Choosing Wisely" guidelines

Preoperative laboratory testing is often necessary and can be invaluable for diagnosis, assessment, and treatment. However, performing routine laboratory tests for patients who are considered otherwise healthy is not usually beneficial and is costly. It is estimated that $18 billion (U.S.) is spent annually on preoperative testing, although how much is wasteful remains unknown. Ideally, a targeted and comprehensive patient history and physical exam should largely determine whether preprocedure laboratory studies should be obtained. Healthcare providers, primarily anesthesiologists, should remain cost-conscious when ordering specific laboratory or imaging tests prior to surgery based on available literature. We review the overall evidence and key points from the Choosing Wisely guidelines, the identification of potential wasteful practices, possible harms of testing, and key clinical findings associated with preoperative laboratory testing.

Clinical management of the pregnant patient undergoing non-obstetric surgery: Review of guidelines

The management principles of non-obstetric surgery during pregnancy are important concepts for all health care providers to be cognizant of. The goals of non-obstetric surgery are to ensure maternal safety, maintain the pregnancy, and ensure fetal well-being. In this regard, organogenesis occurs roughly between days 7-57 and thus, certain medications have a higher incidence of fetal teratogenicity in this first trimester. Some examples of common surgeries performed urgently or emergently include appendectomies, ovarian detorsions, bowel obstruction, trauma, and cholecystectomies. The choice of anesthetic technique and the selection of appropriate anesthetic drugs should be guided by indication for surgery, the nature of the surgery, and the site of the surgical procedure. Many of the concerns for any patients undergoing urgent or emergent surgery must be considered by anesthesia providers along with steps to ensure the fetus has the best outcome.

Pharmacogenomics of Pain Management: The Impact of Specific Biological Polymorphisms on Drugs and Metabolism

PURPOSE OF REVIEW

Pain is multifactorial and complex, often with a genetic component. Pharmacogenomics is a relative new field, which allows for the development of a truly unique and personalized therapeutic approach in the treatment of pain.

RECENT FINDINGS

Until recently, drug mechanisms in humans were determined by testing that drug in a population and calculating response averages. However, some patients will inevitably fall outside of those averages, and it is nearly impossible to predict who those outliers might be. Pharmacogenetics considers a patient's unique genetic information and allows for anticipation of that individual's response to medication. Pharmacogenomic testing is steadily making progress in the management of pain by being able to identify individual differences in the perception of pain and susceptibility and sensitivity to drugs based on genetic markers. This has a huge potential to increase efficacy and reduce the incidence of iatrogenic drug dependence and addiction. The streamlining of relevant polymorphisms of genes encoding receptors, transporters, and drug-metabolizing enzymes influencing the pain phenotype can be an important guide to develop safe new strategies and approaches to personalized pain management. Additionally, some challenges still prevail and preclude adoption of pharmacogenomic testing universally. These include lack of knowledge about pharmacogenomic testing, inadequate standardization of the process of data handling, questionable benefits about the clinical and financial aspects of pharmacogenomic testing-guided therapy, discrepancies in clinical evidence supporting these tests, and doubtful reimbursement of the tests by health insurance agencies.