A Comprehensive Review of the Diagnosis, Treatment, and Management of Urologic Chronic Pelvic Pain Syndrome

PURPOSE OF REVIEW

Urologic chronic pelvic pain syndrome (UCPPS) is a chronic, noncyclic pain condition which can lead to significant patient morbidity and disability. It is defined by pain in the pelvic region, lasting for greater than 3 to 6 months, with no readily identifiable disease process. The aim of this review is to provide a comprehensive update of diagnosis and treatment of UCPPS.

RECENT FINDINGS

UCPPS encompasses chronic pelvic pain syndrome or chronic prostatitis (CP/CPPS) in men and interstitial cystitis or painful bladder syndrome (IC/PBS) in women. Underlying inflammatory, immunologic, and neuropathic components have been implicated in the pathogenesis of UCPPS. For optimal patient management, an individualized and multimodal approach is recommended. Medical management and physical therapy are the mainstays of treatment. Injection therapy may offer additional relief in medically refractory patients. Further minimally invasive management may include spinal cord and peripheral nerve stimulation, though evidence supporting efficacy is limited.

Central Neuropathic Mechanisms in Pain Signaling Pathways: Current Evidence and Recommendations

Purpose

This is a comprehensive review of the current literature on central neuropathic pain mechanisms that is secondary to spinal cord injury. It reviews recent and seminal findings on the pathophysiology, diagnosis, and treatment and compares treatment options and recommendations.

Recent Findings

Neuropathic pain (NP) is a common complication of spinal cord injury (SCI). Chronicity of NP is attributed to increased abundance of inflammatory mediators and ion channel dysfunction leading to afferent nerve sensitization; nerve damage and nerve–glia cross talk have also been implicated. Conventional treatment is medical and has had limited success. Recent studies have made headway in identifying novel biomarkers, including microRNA and psychosocial attributes that can predict progress from SCI to chronic NP (CNP). Recent advances have provided evidence of efficacy for two promising drugs. Baclofen was able to provide good, long-lasting pain relief. Ziconotide, a voltage-gated calcium channel blocker, was studied in a small trial and was able to provide good analgesia in most participants. However, several participants had to be withdrawn because of worrisome creatine phosphokinase (CPK) elevations, and further studies are required to define its safety profile. Non-medical interventions include brain sensitization and biofeedback techniques. These methods have recently had encouraging results, albeit preliminary. Case reports of non-conventional techniques, such as hypnosis, were also reported.

Summary

CNP is a common complication of SCI and is a prevalent disorder with significant morbidity and disability. Conventional medical treatment is limited in efficacy. Recent studies identified baclofen and ziconotide as possible new therapies, alongside non-medical interventions. Further research into the pathophysiology is required to identify further therapy candidates. A multidisciplinary approach, including psychosocial support, medical and non-medical interventions, is likely needed to achieve therapeutic effects in this difficult to treat syndrome.

Postherpetic Neuralgia: Current Evidence on the Topical Film-Forming Spray with Bupivacaine Hydrochloride and a Review of Available Treatment Strategies

PURPOSE OF REVIEW

This is a comprehensive review of the literature about the use of bupivacaine hydrochloride for the treatment of post-herpetic neuralgia (PHN). It briefly reviews the background, biology, diagnosis and conventional treatment for PHN, and then introduces and compares the recent evidence for the use of topical bupivacaine.

RECENT FINDINGS

PHN is defined by pain lasting 90 days or more after the initial presentation of herpes zoster ("Shingles", HZ) rash and is the most common complication of this disease. A product of re-activation of the Varicella-Zoster virus (VZV), HZ is diagnosed more than 1 million times annually in the United States. Approximately 20% of patients with HZ will experience PHN and will continue to suffer intermittent neuropathic symptoms, including itching and pain, that is sharp, stabbing, throbbing or burning, with the pain localized to the site of their original rash. This long-lasting pain compares with the severity of long-standing rheumatics and osteo-arthritis and is accompanied by severe allodynia causing significant suffering, and a financial burden that is manifested in both healthcare costs and loss of quality-adjusted life years. Prevention of PHN may be achieved with the Zoster vaccine, although there is still a large segment of unvaccinated population. Moreover, the Zoster vaccine is not always effective for prevention. Current treatment includes medical (systemic tricyclic antidepressants, anticonvulsants and opioids, topical lidocaine and capsaicin) and interventional (subcutaneous Botox injections, nerve blocks and nerve stimulation) therapies. These therapies are not always effective, and each carries their own profile of side effects and risks. Moreover, up to 50% of patients with PHN are refractory to management. Recent evidence is emerging to support the use of topical local anesthetics for the treatment of PHN. Two small studies recently found topical lidocaine spray to be effective in treating paroxysmal pain attacks associated with PHN. Bupivacaine is a longer-lasting local anesthetic, and a film-forming formulation allows easy and durable application to the affected skin. Recent studies show that topical film-forming bupivacaine is safe and as effective as lidocaine for the treatment of PHN. PHN is an important though common complication of HZ and can cause long-lasting pain and disability. Current treatment for PNH is limited by efficacy and safety profiles of individual therapies. Recent evidence points to topical local anesthetics as an effective and safe alternative to conventional therapy. Film-forming bupivacaine may offer a durable and safe option for this otherwise difficult to treat syndrome.

Upper extremity regional anesthesia techniques: A comprehensive review for clinical anesthesiologists

Surgeries and chronic pain states of the upper extremity are quite common and pose unique challenges for the clinical anesthesiology and pain specialists. Most innervation of the upper extremity involves the brachial plexus. The four most common brachial plexus blocks performed in clinical setting include the interscalene, supraclavicular, infraclavicular, and axillary brachial plexus blocks. These blocks are most commonly performed with the use of ultrasound-guided techniques, whereby analgesia is achieved by anesthetizing the brachial plexus at different levels such as the roots, divisions, cords, and branches. Additional regional anesthetic techniques for upper extremity surgery include wrist, intercostobrachial, and digital nerve blocks, which are most frequently performed using landmark anatomical techniques. This review provides a comprehensive summary of each of these blocks including anatomy, best practice techniques, and potential complications.

Preoperative frailty assessment combined with prehabilitation and nutrition strategies: Emerging concepts and clinical outcomes

Important elements of the preoperative assessment that should be addressed for the older adult population include frailty, comorbidities, nutritional status, cognition, and medications. Frailty has emerged as a plausible predictor of adverse outcomes after surgery. It is present in older patients and is characterized by multisystem physiologic decline, increased vulnerability to stressors, and adverse clinical outcomes. Preoperative preparation may include a prehabilitation program, which aims to address nutritional insufficiencies, modify chronic polypharmacy, and enhance physical and respiratory conditions prior to hospital admission. Special considerations are taken for particularly high-risk patients, where the approach to prehabilitation can address specific, individual risk factors. Identifying patients who are nutritionally deficient allows practitioners to intervene preoperatively to optimize their nutritional status, and different strategies are available, such as immunonutrition. Previous studies have shown an association between increased frailty and the risk of postoperative complications, morbidity, hospital length of stay, and 30-day and long-term mortality following general surgical procedures. Evidence from numerous studies suggests a potential benefit of including a standard assessment of frailty as part of the preoperative workup of older adult patients. Studies addressing validated frailty assessments and the quantification of their predictive capabilities in various surgeries are warranted.

Perioperative strategies for the reduction of postoperative pulmonary complications

Postoperative pulmonary complications (PPCs), estimated between 2.0% and 5.6% in the general surgical population and 20-70% for upper abdominal and thoracic surgeries, are a significant factor leading to poor patient outcomes. Efforts to decrease the incidence of PPCs such as bronchospasm, atelectasis, exacerbations of underlying chronic lung conditions, infections (bronchitis and pneumonia), prolonged mechanical ventilation, and respiratory failure, begins with a detailed preoperative risk evaluation. There are several available preoperative tests to estimate the risk of PPCs. However, the value of some of these studies to estimate PPCs remains controversial and is still debated. In this review, the preoperative risk assessment of PPCs is examined along with preoperative pulmonary tests to estimate risk, intraoperative, and procedure-associated risk factors for PPCs, and perioperative strategies to decrease PPCs. The importance of minimizing these events is reflected in the fact that nearly 25% of postoperative deaths occurring in the first week after surgery are associated with PPCs. This review provides important information to help clinical anesthesiologists to recognize potential risks for pulmonary complications and allows strategies to create an appropriate perioperative plan for patients.

Perioperative acute kidney injury: Stratification and risk reduction strategies

Perioperative acute kidney injury (AKI) is associated with increased morbidity and mortality. Patient comorbidities, the type of surgery, timing of surgery, and exposure to nephrotoxins are important contributors for developing acute kidney injury. Urgent or emergent surgery, cardiac, and organ transplantation procedures are associated with a higher risk of acute kidney injury. Nephrotoxic drugs, contrast dye, and diuretics can worsen preexisting kidney dysfunction or act as an additive and/or synergistic insult to perioperative injury. A history of preoperative chronic kidney disease is the main risk factor for developing AKI, conferring as much as a 10-fold risk. However, beyond the preoperative renal function, the development of AKI is a complex phenomenon that involves a combination of patient-related and surgery-related factors.

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.

Dexmedetomidine in Enhanced Recovery After Surgery (ERAS) Protocols for Postoperative Pain

PURPOSE OF REVIEW

Effective acute pain management has evolved considerably in recent years and is a primary area of focus in attempts to defend against the opioid epidemic. Persistent postsurgical pain (PPP) has an incidence of up to 30-50% and has negative outcome of quality of life and negative burden on individuals, family, and society. The 2016 American Society of Anesthesiologists (ASA) guidelines states that enhanced recovery after surgery (ERAS) forms an integral part of Perioperative Surgical Home (PSH) and is now recommended to use a multimodal opioid-sparing approach for management of postoperative pain. As such, dexmedetomidine is now being used as part of ERAS protocols along with regional nerve blocks and other medications, to create a satisfactory postoperative outcome with reduced opioid consumption in the Post anesthesia care unit (PACU).

RECENT FINDINGS

Dexmedetomidine, a selective alpha2 agonist, possesses analgesic effects and has a different mechanism of action when compared with opioids. When dexmedetomidine is initiated at the end of a procedure, it has a better hemodynamic stability and pain response than ropivacaine. Dexmedetomidine can be used as an adjuvant in epidurals with local anesthetic sparing effects. Its use during nerve blocks results in reduced postoperative pain. Also, local infiltration of IV dexmedetomidine is associated with earlier discharge from PACU. Perioperative use of dexmedetomidine has significantly improved postoperative outcomes when used as part of ERAS protocols. An in-depth review of the use of dexmedetomidine in ERAS protocols is presented for clinical anesthesiologists.

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.

The Role of Exparel Plus Meloxicam for Postoperative Pain Management

PURPOSE OF REVIEW

Acute postoperative pain reduction is a major target against the opioid crisis. While opioids have traditionally been the mainstay for postoperative analgesia, current practice has focused on a multimodal approach to pain control, including ultrasound-guided blocks with longer acting local anesthetic agents.

RECENT FINDINGS

Non-steroidal anti-inflammatory drugs (NSAIDs), such as meloxicam, are an important class of medications utilized to manage pain in the perioperative period. An additional treatment used in perioperative or postoperative pain relief is Exparel, a bupivacaine (sodium channel blocker) liposomal injectable suspension with a 3-4-day duration of action. The long-acting mechanism and formulation of Exparel consistently has demonstrated decreased opioid use and pain scores in patients undergoing many different surgical procedures. A concern is that pH negatively alters the efficacy of bupivacaine, as in cases of inflamed tissue and acidic fluid pH. For this reason, a combination medication with both meloxicam and bupivacaine has been developed, which normalizes pH and has anti-inflammatory and anti-pain conduction properties. Clinical studies demonstrate that this combination agent can be extremely beneficial in treating postoperative pain. This manuscript summarizes the newest developments with regard to liposomal bupivacaine and the non-steroidal meloxicam, their roles in effective treatment of postoperative pain, contraindications, special considerations of using these medications, and future considerations. HTX-011 pairs up a new extended-release formulation of the local anesthetic bupivacaine with meloxicam, a well-established non-steroidal anti-inflammatory drug (NSAID).

Kratom-Pharmacology, Clinical Implications, and Outlook: A Comprehensive Review

Kratom, or Mitragyna, is a tropical plant indigenous to Southeast Asia, with unique pharmacological properties. It is commonly consumed by preparing the leaves into decoction or tea, or by grinding them into a powder. Recent evidence has revealed that kratom has physiological effects similar to opioids, including pain relief and euphoria, as well as stimulant properties, which together raise potential concern for dependence and addiction. Moreover, growing evidence suggests that the prevalence of kratom use is increasing in many parts of the world, raising important considerations for healthcare providers. This manuscript will discuss the most current epidemiology, pharmacology, toxicity, and management related to kratom, while seeking to provide a contemporary perspective on the issue and its role in the greater context of the opioid epidemic.

Ultrasound practice for chronic pain procedures: A comprehensive review

Chronic pain management techniques have evolved in recent years. With regard to this, ultrasound (US) technology has become a standard for most acute pain procedures and essential for postsurgical pain relief and enhanced recovery after surgery protocols. This manuscript summarizes clinical studies evaluating US use for chronic pain management and compares efficacy with standard techniques including fluoroscopy (FL). US possesses several unique benefits when compared with FL, including elimination of radiation exposure while providing similar clinical outcomes. In summary, US use for chronic pain procedures is emerging as a viable, safe, and effective modality. Additional studies are needed to best appreciate US and its role in chronic pain management.

Newer nerve blocks in pediatric surgery

PURPOSE OF THE REVIEW

The purpose of this manuscript is to provide a brief discussion of the current direction in pediatric regional anesthesia, highlighting both newer nerve blocks and techniques and traditional nerve blocks.

RECENT FINDINGS

The number of nerve blocks performed in pediatric patients continues to increase. This growth is likely related in part to the recent focus on perioperative multimodal analgesia, in addition to growing data demonstrating safety and efficacy in this patient population. Multiple studies by the Pediatric Regional Anesthesia Network (PRAN) and the French-Language Society of Pediatric Anesthesiologists (ADARPEF) have demonstrated lack of major complications and general overall safety with pediatric nerve blocks. The growing prevalence of ultrasound-guided regional anesthesia has not only improved the safety profile, but also increased the efficacy of both peripheral nerve blocks and perineural catheters.

SUMMARY

As the push for multimodal analgesia increases and the breadth of pediatric regional anesthesia continues to expand, further large prospective studies will be needed to demonstrate continued efficacy and overall safety.

Vasodepressor Effects of Adenosine in the Cat are Independent of Cyclooxygenase, Potassium Channels, and Nitric Oxide Pathways

BACKGROUND

Pulmonary arterial hypertension is a hemodynamic disorder. Signs and symptoms are generally difficult to recognize because they are non-specific. The current treatment for pulmonary arterial hypertension offers no cure or prevention; therefore, it is important to explore treatment avenues for novel pulmonary arterial hypertension treatments. In this study, we tested the hypothesis: pulmonary vasodilator responses of adenosine are dependent on the activation of L-type calcium channels, independent of the synthesis of nitric oxide from L-arginine, activation of adenosine triphosphate-sensitive potassium channels, and the release of cyclooxygenase products.

METHODS

We performed an isolated lobar lung preparation in mongrel cats. The thromboxane A2 analog U-46619 was used to increase lobar arterial pressure to a high steady level. We recorded responses to adenosine and other vasodepressor agents in the pulmonary vascular bed of a cat under conditions of controlled pulmonary blood flow and constant left atrial pressure.

RESULTS

These data show that adenosine has significant vasodepressor activity in the pulmonary vascular bed of the cat. The data suggest that pulmonary vasodilator responses to adenosine are partially dependent on the activation of adenosine 1 and 2 receptor pathways, and independent of the activation of cyclooxygenase activation, adenosine triphosphate-sensitive K + channels, or synthesis of nitric oxide in the pulmonary vascular bed of the cat.

CONCLUSIONS

Vasodepressor effects of adenosine are species specific, and this species specificity will impact the development of future testing and treatments for pulmonary arterial hypertension. Clinical studies are warranted to see if adenosine moieties could play a therapeutic role in patients with pulmonary arterial hypertension and/or other pulmonary pathogeneses.

Stem Cell Therapies for Treatment of Discogenic Low Back Pain: a Comprehensive Review

PURPOSE OF REVIEW

Discogenic low back pain (DLBP) stems from pathology in one or more intervertebral discs identified as the root cause of the pain. It is the most common type of chronic low back pain (LBP), representing 26-42% of attributable cases.

RECENT FINDINGS

The clinical presentation of DLBP includes increased pain when sitting, coughing, or sneezing, and experiencing relief when standing or ambulating. Dermatomal radiation of pain to the lower extremity and neurological symptoms including numbness, motor weakness, and urinary or fecal incontinence are signs of advanced disease with disc prolapse, nerve root compression, or spinal stenosis. Degenerative disc disease is caused by both a decrease in disc nutrient supply causing decreased oxygen, lowered pH, and lessened ability of the intervertebral disc (IVD) to respond to increased load or injury; moreover, changes in the extracellular matrix composition cause weakening of the tissue and skewing the extracellular matrix's (ECM) harmonious balance between catabolic and anabolic factors for cell turnover in favor of catabolism. Thus, the degeneration of the disc causes a shift from type II to type I collagen expression by NP cells and a decrease in aggrecan synthesis leads to dehydrated matrix cells ultimately with loss of swelling pressure needed for mechanical support. Cell-based therapies such as autologous nucleus pulposus cell re-implantation have in animal models and human trials shown improvements in LBP score, retention of hydration in IVD, and increased disc height. Percutaneously delivered multipotent mesenchymal stem cell (MSC) therapy has been proposed as a potential means to uniquely ameliorate discogenic LBP holistically through three mechanisms: mitigation of primary nociceptive disc pain, slow or reversal of the catabolic metabolism, and restoration of disc tissue. Embryonic stem cells (ESCs) can differentiate into cells of all three germ layers in vitro, but their use is hindered related to ethical concerns, potential for immune rejection after transplantation, disease, and teratoma formation. Another similar approach to treating back pain is transplantation of the nucleus pulposus, which, like stem cell therapy, seeks to address the underlying cause of intervertebral disc degeneration by aiming to reverse the destructive inflammatory process and regenerate the proteoglycans and collagen found in healthy disc tissue. Preliminary animal models and clinical studies have shown mesenchymal stem cell implantation as a potential therapy for IVD regeneration and ECM restoration via a shift towards favorable anabolic balance and reduction of pain.

Fascia iliaca block, history, technique, and efficacy in clinical practice

The facsia iliaca block (FIB) is a relatively new regional technique where local anesthetic is delivered within the fascia iliaca region. Indications for a FIB include surgical anesthesia to the lower extremity after knee, femoral shaft, hip surgery, management of cancer pain or pain secondary to inflammatory conditions of the lumbar plexus, as well as treatment of acute pain in the setting of trauma, fracture, or burns. The FIB may be performed using either a loss of resistance technique or an ultrasound (US)-guided technique; however, the use of US has become commonplace and resulted in improved femoral nerve and obturator nerve motor blocks. The main targets of the FIB are the predominant nerves contained in the fascia iliaca compartment (FIC), namely the femoral nerve and the lateral femoral cutaneous nerve. The FIB US guided technique is beneficial to patients and the possibility to perform FIB should be discussed and coordinated with surgical staff appropriately, considering its superiority to general or epidural anesthesia.

Recent technological advancements in regional anesthesia

Just two decades ago, regional anesthesia was performed blindly with dubious outcomes and little support from surgeons and patients. Technological advances in regional anesthesia have revolutionized techniques and largely improved outcomes. Ultrasound (US) technology continues to advance and has become more affordable. Improvements have come in the form of picture quality, resolution, portability, and smaller equipment. The US technology can identify otherwise unrecognized pathology and can help to optimize patient flow by allowing for more accurate triage and effective treatments and providing timelier interventions. In recent years, several different strategies to help improve and ease US-guided needle identification and placement have been developed, including magnetically guided needle US technology. Three-dimensional (3D) and four-dimensional (4D) US use is another potential way to help improve first-pass success and limit patient harm for regional anesthetics. The advent of echogenic needles and the resulting improvement in needle visualization under US has had a positive impact on physician comfort in performing regional anesthesia and on visualization time of the needle during US-guided procedures. To reduce variability and to reduce the anesthesiologist's workload, the use of robots in regional anesthesia has been assessed in recent years. Peripheral nerve stimulation (PNS) has also demonstrated efficacy in acute and chronic pain settings. Additional research and randomized controlled trials are necessary to evaluate novel technologies.

Emerging Novel Pharmacological Non-opioid Therapies in Headache Management: a Comprehensive Review

PURPOSE OF REVIEW

Chronic headache is a significant worldwide problem despite advances in treatment options. Chronic headaches can have significant a detrimental impact on the activities of daily living.

RECENT FINDINGS

Patients who do not obtain relief from chronic head and neck pain from conservative treatments are commonly being managed with interventional treatments. These interventional treatment options include botulinum toxin A, injections, local occipital nerve anesthetic and corticosteroid infiltration, occipital nerve subcutaneous stimulation and occipital nerve pulsed radiofrequency (PRF), sphenopalatine ganglion block, and radiofrequency techniques. Recently, evidence has emerged to support non-opioid-based drug and interventional approaches. Overall, more research is necessary to clarify the safety and efficacy of interventional treatments and to better understand the pathogenesis of chronic headache pain.

Update on the pharmacogenomics of pain management

Pharmacogenomics is the study of genetic variants that impact drug effects through changes in a drug’s pharmacokinetics and pharmacodynamics. Pharmacogenomics is being integrated into clinical pain management practice because variants in individual genes can be predictive of how a patient may respond to a drug treatment. Pain is subjective and is considered challenging to treat. Furthermore, pain patients do not respond to treatments in the same way, which makes it hard to issue a consistent treatment regimen for all pain conditions. Pharmacogenomics would bring consistency to the subjective nature of pain and could revolutionize the field of pain management by providing personalized medical care tailored to each patient based on their gene variants. Additionally, pharmacogenomics offers a solution to the opioid crisis by identifying potentially opioid-vulnerable patients who could be recommended a nonopioid treatment for their pain condition. The integration of pharmacogenomics into clinical practice creates better and safer healthcare practices for patients. In this article, we provide a comprehensive history of pharmacogenomics and pain management, and focus on up to date information on the pharmacogenomics of pain management, describing genes involved in pain, genes that may reduce or guard against pain and discuss specific pain management drugs and their genetic correlations.

Adjuvants in clinical regional anesthesia practice: A comprehensive review

Adjuvants are medications that work synergistically with local anesthetics to help enhance the duration and quality of analgesia in regional techniques. Regional anesthesia has become more prevalent as evidence continues to show efficacy, enhancement of patient care, increased patient satisfaction, and improved patient safety. Practitioners in the perioperative setting need to not only be familiar with regional techniques but also the medications used for them. Some examples of adjuvant medications for regional techniques include dexamethasone, alpha 2 agonists such as clonidine and dexmedetomidine, midazolam, buprenorphine, NMDA antagonists, including ketamine and magnesium, neostigmine, sodium bicarbonate, epinephrine, and non-steroidal anti-inflammatory drugs. The aim of the present investigation, therefore, is to provide a comprehensive review of the most commonly used non-opioid adjuvants in clinical practice today. Regional adjuvants can improve patient safety, increase patient satisfaction, and enhance clinical efficacy. Future studies and best practice techniques can facilitate standardization of regional anesthesia adjuvant dosing when providing nerve blocks in clinical practice.

Point of care ultrasound for the clinical anesthesiologist

Diagnostic ultrasonography was first utilized in the 1940s. The past 70+ years have seen an explosion in both ultrasound technology and availability of ultrasound technology to more and more clinicians. As ultrasound technology and availability have grown, the utility of ultrasound technology in the clinical setting as only been limited by clinicians' imagination. Due to its lack of radiation, non-invasive nature, and gentle learning curve, medical ultrasonography is now a tremendously useful Point of Care technology in the clinical arena. What follows is a discussion of Point of Care Ultrasound (PoCUS) and how it can be incorporated in the daily practice of any regional anesthesiology. While most regional anesthesiologists usually focus on the interventional aspects of ultrasonography (i.e. nerve blocks), our discussion will center on the diagnostic value of ultrasonography-especially concerning assessment of cardiac physiology and pathophysiology, gastric anatomy, airway anatomy, and intracranial pathophysiology. After reading and reviewing this chapter, the learner will have the knowledge to start training themselves in a variety of PoCUS exams that will allow rapid diagnosis of normal and abnormal patient conditions. Once an accurate diagnosis is established, the anesthesiologist and his/her team can then confidently optimize an anesthetic pain, prevent harm, and/or treat a patient condition. In this day and age, the ability to rapidly establish an accurate diagnosis cannot be overstated-especially in a critical situation. It is the authors' sincerest hope that the following discussion will help regional anesthesiologist to become even better and well-rounded clinical leaders.

Regional techniques for head and neck surgical procedures

Regional anesthesia has evolved as an important tool for anesthesiologists and surgeons managing patients for surgery of the head and neck region. In recent years, ultrasound use has increased significantly, and newer nerve blocks have been established for surgeries of the head and regions. In this review, anatomy, indications, efficacy, and potential side effects of regional anesthesia for the head and neck region are presented. Evolving practice strongly suggests that regional nerve blocks for the head and neck region are safe and effective. Future studies and education will likely evolve practice to make these regional techniques standards for future surgeries of the head and neck region.

Comprehensive Perioperative Management Considerations in Patients Taking Methadone

PURPOSE OF REVIEW

Well-informed staff can help decrease risks and common misconceptions regarding opioid-tolerant patients, especially those taking methadone.

RECENT FINDINGS

In 2015, opioid pain relievers were the second most used drug at 3.8 million. Overdose death was three times greater in 2015 than in 2000. Medication-assisted treatment was sought by more than 2 million individuals with substance use disorder, one of which is methadone. Chronic pain affects millions of adults in the USA. Opioid therapy is widely used among these adults. Related to the risk of abuse and dependence, guidelines suggest that opioid therapy may not be considered first-line treatment. A multidisciplinary approach, including thorough preoperative evaluation, the utilization of multimodal pain management strategies, and opioid-sparing techniques in both the intraoperative and postoperative periods will allow for the best possible outcome.

Thoracic Outlet Syndrome: A Comprehensive Review of Pathophysiology, Diagnosis, and Treatment

Thoracic outlet syndrome, a group of diverse disorders, is a collection of symptoms in the shoulder and upper extremity area that results in pain, numbness, and tingling. Identification of thoracic outlet syndrome is complex and a thorough clinical examination in addition to appropriate clinical testing can aide in diagnosis. Practitioners must consider the pathology of thoracic outlet syndrome in their differential diagnosis for shoulder and upper extremity pain symptoms so that patients are directed appropriately to timely therapeutic interventions. Patients with a definitive etiology who have failed conservative management are ideal candidates for surgical correction. This manuscript will discuss thoracic outlet syndrome, occurrence, physical presentation, clinical implications, diagnosis, and management.

Metabolic and the Surgical Stress Response Considerations to Improve Postoperative Recovery

PURPOSE OF REVIEW

Enhanced recovery pathways are a multimodal, multidisciplinary approach to patient care that aims to reduce the surgical stress response and maintain organ function resulting in faster recovery and improved outcomes.

RECENT FINDINGS

A PubMed literature search was performed for articles that included the terms of metabolic surgical stress response considerations to improve postoperative recovery. The surgical stress response occurs due to direct and indirect injuries during surgery. Direct surgical injury can result from the dissection, retraction, resection, and/or manipulation of tissues, while indirect injury is secondary to events including hypotension, blood loss, and microvascular changes. Greater degrees of tissue injury will lead to higher levels of inflammatory mediator and cytokine release, which ultimately drives immunologic, metabolic, and hormonal processes in the body resulting in the stress response. These processes lead to altered glucose metabolism, protein catabolism, and hormonal dysregulation among other things, all which can impede recovery and increase morbidity. Fluid therapy has a direct effect on intravascular volume and cardiac output with a resultant effect on oxygen and nutrient delivery, so a balance must be maintained without excessively loading the patient with water and salt. All in all, attenuation of the surgical stress response and maintaining organ and thus whole-body homeostasis through enhanced recovery protocols can speed recovery and reduce complications. The present investigation summarizes the clinical application of enhanced recovery pathways, and we will highlight the key elements that characterize the metabolic surgical stress response and improved postoperative recovery.

The Role of Complementary and Alternative Medicine Treatments in Fibromyalgia: a Comprehensive Review

PURPOSE OF REVIEW

Fibromyalgia is a complex chronic pain syndrome that can have debilitating consequences for affected patients. When compared to the general population, patients with fibromyalgia experience lowered mechanical and thermal pain thresholds, altered temporal summation of painful stimuli, and higher than normal pain ratings for known noxious stimuli.

RECENT FINDINGS

There is no definitive cure for fibromyalgia and treatment primarily focuses on both symptom management and improving patient quality of life. This treatment strategy involves a comprehensive multidisciplinary approach consisting of lifestyle modifications, pharmacologic measures, and other complementary approaches including but not limited to acupuncture, yoga, tai chi, and meditation. This manuscript will discuss the diagnosis and treatment of fibromyalgia, as well as complementary and alternative therapies that should be considered by healthcare providers.

Responsible, Safe, and Effective Use of Antithrombotics and Anticoagulants in Patients Undergoing Interventional Techniques: American Society of Interventional Pain Physicians (ASIPP) Guidelines

BACKGROUND

Interventional pain management involves diagnosis and treatment of chronic pain. This specialty utilizes minimally invasive procedures to target therapeutics to the central nervous system and the spinal column. A subset of patients encountered in interventional pain are medicated using anticoagulant or antithrombotic drugs to mitigate thrombosis risk. Since these drugs target the clotting system, bleeding risk is a consideration accompanying interventional procedures. Importantly, discontinuation of anticoagulant or antithrombotic drugs exposes underlying thrombosis risk, which can lead to significant morbidity and mortality especially in those with coronary artery or cerebrovascular disease. This review summarizes the literature and provides guidelines based on best evidence for patients receiving anti-clotting therapy during interventional pain procedures.

STUDY DESIGN

Best evidence synthesis.

OBJECTIVE

To provide a current and concise appraisal of the literature regarding an assessment of the bleeding risk during interventional techniques for patients taking anticoagulant and/or antithrombotic medications.

METHODS

A review of the available literature published on bleeding risk during interventional pain procedures, practice patterns and perioperative management of anticoagulant and antithrombotic therapy was conducted. Data sources included relevant literature identified through searches of EMBASE and PubMed from 1966 through August 2018 and manual searches of the bibliographies of known primary and review articles.

RESULTS

1. There is good evidence for risk stratification by categorizing multiple interventional techniques into low-risk, moderate-risk, and high-risk. Also, their risk should be upgraded based on other risk factors.2. There is good evidence for the risk of thromboembolic events in patients who interrupt antithrombotic therapy. 3. There is good evidence supporting discontinuation of low dose aspirin for high risk and moderate risk procedures for at least 3 days, and there is moderate evidence that these may be continued for low risk or some intermediate risk procedures.4. There is good evidence that discontinuation of anticoagulant therapy with warfarin, heparin, dabigatran (Pradaxa®), argatroban (Acova®), bivalirudin (Angiomax®), lepirudin (Refludan®), desirudin (Iprivask®), hirudin, apixaban (Eliquis®), rivaroxaban (Xarelto®), edoxaban (Savaysa®, Lixiana®), Betrixaban(Bevyxxa®), fondaparinux (Arixtra®) prior to interventional techniques with individual consideration of pharmacokinetics and pharmacodynamics of the drugs and individual risk factors increases safety.5. There is good evidence that diagnosis of epidural hematoma is based on severe pain at the site of the injection, rapid neurological deterioration, and MRI with surgical decompression with progressive neurological dysfunction to avoid neurological sequelae.6. There is good evidence that if thromboembolic risk is high, low molecular weight heparin bridge therapy can be instituted during cessation of the anticoagulant, and the low molecular weight heparin can be discontinued 24 hours before the pain procedure.7. There is fair evidence that the risk of thromboembolic events is higher than that of epidural hematoma formation with the interruption of antiplatelet therapy preceding interventional techniques, though both risks are significant.8. There is fair evidence that multiple variables including anatomic pathology with spinal stenosis and ankylosing spondylitis; high risk procedures and moderate risk procedures combined with anatomic risk factors; bleeding observed during the procedure, and multiple attempts during the procedures increase the risk for bleeding complications and epidural hematoma.9. There is fair evidence that discontinuation of phosphodiesterase inhibitors is optional (dipyridamole [Persantine], cilostazol [Pletal]. However, there is also fair evidence to discontinue Aggrenox [dipyridamole plus aspirin]) 3 days prior to undergoing interventional techniques of moderate and high risk. 10. There is fair evidence to make shared decision making between the patient and the treating physicians with the treating physician and to consider all the appropriate risks associated with continuation or discontinuation of antithrombotic or anticoagulant therapy.11. There is fair evidence that if thromboembolic risk is high antithrombotic therapy may be resumed 12 hours after the interventional procedure is performed.12. There is limited evidence that discontinuation of antiplatelet therapy (clopidogrel [Plavix®], ticlopidine [Ticlid®], Ticagrelor [Brilinta®] and prasugrel [Effient®]) avoids complications of significant bleeding and epidural hematomas.13. There is very limited evidence supporting the continuation or discontinuation of most NSAIDs, excluding aspirin, for 1 to 2 days and some 4 to 10 days, since these are utilized for pain management without cardiac or cerebral protective effect.

LIMITATIONS

The continued paucity of the literature with discordant recommendations.

CONCLUSION

Based on the survey of current literature, and published clinical guidelines, recommendations for patients presenting with ongoing antithrombotic therapy prior to interventional techniques are variable, and are based on comprehensive analysis of each patient and the risk-benefit analysis of intervention.

KEY WORDS

Perioperative bleeding, bleeding risk, practice patterns, anticoagulant therapy, antithrombotic therapy, interventional techniques, safety precautions, pain.

Management of Challenging Pharmacologic Issues in Chronic Pain and Substance Abuse Disorders

Drug abuse and addiction are persistent problems in the United States and around the world. This is an ongoing issue for health care providers, as substance abuse is seen in 25% to 40% of patients admitted to hospitals for general treatment. Many patients with substance use disorders have a higher risk for adverse events; however, only a small percentage will volunteer information regarding prior substance use. This article discusses the present opioid crisis, mechanisms behind chronic pain and substance abuse, current clinical findings, treatment therapies, and abuse deterrents.

Adjunct medications for peripheral and neuraxial anesthesia

Regional and neuraxial anesthesia can provide a safer perioperative experience, greater satisfaction, reduced opioid consumption, and reduction of pain, while minimizing side effects. Ultrasound technology has aided clinicians in depositing local anesthetic medication in precise proximity to targeted peripheral nerves. There are a plethora of adjuvants that have been utilized to prolong local anesthetic actions and enhance effects in peripheral nerve blocks. This manuscript describes the current state of the use of adjuncts, e.g., dexmedetomidine, dexamethasone, clonidine, epinephrine, etc., in regional anesthesia. Additionally, evidence behind dosing and block prolongation is summarized along with patient outcomes, adverse effects, and future directions.

Pulmonary vasodilators: Latest evidence and outcomes in the perioperative setting

Numerous conditions give rise to pulmonary arterial hypertension (PAH), with most of them being idiopathic. Signs and symptoms are generally difficult to recognize initially because they present as nonspecific and typically are mistaken for age-related physiological processes or alternate medical conditions. Many advances have been made toward PAH-specific therapies that have led to advanced clinical management of the disease. The present investigation describes new pulmonary vasodilator agents that are currently available or under development that could impact perioperative management. The 6-min walk test is the gold standard in assessing the efficacy of any pulmonary hypertension treatment, and the only drug to show any mortality benefit in pulmonary hypertension is epoprostenol. The present investigation also describes the latest evidence on using these medications in the perioperative period, including clinical trials and practice guidelines. Future direction for research and clinical management of pulmonary hypertension is described.

New opioid receptor modulators and agonists

There has been significant research to develop an ideal synthetic opioid. Opioids with variable properties possessing efficacy and with reduced side effects have been synthesized when compared to previously used agents. An opioid modulator is a drug that can produce both agonistic and antagonistic effects by binding to different opioid receptors and therefore cannot be classified as one or the other alone. These compounds can differ in their structures while still possessing opioid-mediated actions. This review will discuss TRV130 receptor modulators and other novel opioid receptor modulators, including Mitragyna "Kratom," Ignavine, Salvinorin-A, DPI-289, UFP-505, LP1, SKF-10,047, Cebranopadol, Naltrexone-14-O-sulfate, and Naloxegol. In summary, the structural elucidation of opioid receptors, allosteric modulation of opioid receptors, new opioid modulators and agonists, the employment of optogenetics, optopharmacology, and next-generation sequencing of opioid receptor genes and related functionality should create exciting new avenues for research and therapeutic development to treat conditions including pain, opioid abuse, and addiction.

Perioperative implications of common and newer psychotropic medications used in clinical practice

Psychotropic medications are widely prescribed by clinicians as both primary therapy for a variety of psychiatric and neurodegenerative diseases and as adjunctive analgesics for use in the perioperative period. It is critical to understand various modes of action, drug-drug interactions, side effects, and clinical implications. Health care providers must understand how these medications interact with anesthetics, as well as other drugs used in perioperative care. We review relevant psychiatric and neurodegenerative diseases, psychotropic medications used to treat them, and how these medications interact with anesthetics and drugs used in perioperative care. We will also discuss emerging psychotropic drugs and the challenges they may create during the perioperative period. Future direction of investigation into the role of these drugs during the perioperative period and implications is also discussed.

An Update on Nonopioids: Intravenous or Oral Analgesics for Perioperative Pain Management

Despite an appreciation for many unwanted physiologic effects from inadequate postoperative pain relief, moderate to severe postoperative pain remains commonplace. Although treatment options have evolved in recent years, the use of nonopioid analgesics agents can reduce acute pain-associated morbidity and mortality. This review focuses on the importance of effective postoperative nonopioid analgesic agents, such as acetaminophen, nonsteroidal anti-inflammatory agents, gabapentinoid agents, NMDA antagonists, alpha 2 agonists, and steroids, in opioid sparing and enhancing recovery. A careful literature review focusing on these treatment options, potential benefits, and side effects associated with these strategies is emphasized in this review.

Pulmonary Vasodilators and Anesthesia Considerations

Pulmonary hypertension (PH) is a complex disease process of the pulmonary vasculature system characterized by elevated pulmonary arterial pressures. Patients with PH are at increased risk for morbidity and mortality, including intraoperatively and postoperatively. Appreciation by the clinical anesthesiologist of the pathophysiology of PH is warranted. Careful and meticulous strategy using appropriate anesthetic medications, pulmonary vasodilator and inotropic agents, and careful fluid management all increase the likelihood of the best possible outcome in this challenging patient population.

Pharmacologic Considerations of Anesthetic Agents in Pediatric Patients: A Comprehensive Review

Acute pain in the pediatric population has important differences in terms of biology, intrapopulation variation, and epidemiology. Discussion as to the pharmacologic considerations of anesthetic agents, such as induction agents, neuromuscular blockers, opioids, local anesthetics, and adjuvant agents, is presented in this article. Special considerations and concerns, such as risk for propofol infusion syndrome and adverse potential side effects of anesthesia agents, are discussed. Anesthesiologists managing pediatric patients need to have a firm understanding of physiologic and pharmacologic differences compared with the adult population. Future studies to improve the understanding of pharmacokinetics in the pediatric population are needed.

Adjuvant Agents in Regional Anesthesia in the Ambulatory Setting

PURPOSE OF REVIEW

A majority of surgical practice has involved ambulatory centers with the number of outpatient operations in the USA doubling to 26.8 million per year. Local anesthesia delivery provides numerous benefits, including increased satisfaction, earlier discharge, and reduction in unplanned hospital admission. Further, with the epidemic of opioid mediated overdoses, local anesthesia can be a key tool in providing an opportunity to reduce the need for other analgesics postoperatively.

RECENT FINDINGS

Adjuvants such as epinephrine and clonidine enhance local anesthetic clinical utility. Further, dexmedetomidine prolongs regional blockade duration effects. There has also been a significant interest recently in the use of dexamethasone. Studies have demonstrated a significant prolongation in motor and sensory block with perineural dexamethasone. Findings are conflicting as to whether intravenous dexamethasone has similar beneficial effects. However, considering the possible neurotoxicity effects, which perineural dexamethasone may present, it would be prudent not to consider intravenously administered dexamethasone to prolong regional block duration. Many studies have also demonstrated neurotoxicity from intrathecally administered midazolam. Therefore, midazolam as an adjuvant is not recommended. Magnesium prolongs regional block duration but related to paucity of studies as of yet, cannot be recommended. Tramadol yields inconsistent results and ketamine is associated with psychotomimetic adverse effects. Buprenorphine consistently increases regional block duration and reduce opioid requirements by a significant amount. Future studies are warranted to define best practice strategies for these adjuvant agents. The present review focuses on the many roles of local anesthetics in current ambulatory practice.

The Role of Acupuncture in Pain Management

Acupuncture is a traditional Chinese practice of medicine that has gained popularity in Western culture and around the world. It involves the insertion of thin needles into the skin to stimulate nerves, muscles, and connective tissues throughout the body with the goal of alleviating pain, tension, and stress. More broadly, acupuncture is actually a family of different procedures. Conceptually, it is believed to stimulate the body's meridians, or energy-carrying channels, in an attempt to correct imbalances and to restore health. These benefits are thought to be derived from the proximity of acupoints with nerves through intracellular calcium ions. This lesson outlines a brief history of acupuncture and how it may be used to treat various types of physical and emotional pain and specific conditions, including overactive bladder and psoriasis. Acupuncture has been demonstrated to enhance endogenous opiates, such as dynorphin, endorphin, encephalin, and release corticosteroids, relieving pain and enhancing the healing process. There are associated risks; however, serious side effects are rare. When compared to traditional methods of pain management, more studies are warranted in order to establish the efficacy of acupuncture and its place in pain management.

ArrayNinja: An Open Source Platform for Unified Planning and Analysis of Microarray Experiments

Microarray-based proteomic platforms have emerged as valuable tools for studying various aspects of protein function, particularly in the field of chromatin biochemistry. Microarray technology itself is largely unrestricted in regard to printable material and platform design, and efficient multidimensional optimization of assay parameters requires fluidity in the design and analysis of custom print layouts. This motivates the need for streamlined software infrastructure that facilitates the combined planning and analysis of custom microarray experiments. To this end, we have developed ArrayNinja as a portable, open source, and interactive application that unifies the planning and visualization of microarray experiments and provides maximum flexibility to end users. Array experiments can be planned, stored to a private database, and merged with the imaged results for a level of data interaction and centralization that is not currently attainable with available microarray informatics tools.