IPACK Block Efficacy for Acute Pain Management after Total Knee Replacement: A Review.

PURPOSE OF REVIEW: Patients often experience a significant degree of knee pain following total knee replacement (TKR). To alleviate this pain, nerve blocks may be performed such as the adductor canal block (ACB). However, ACBs are unable to relieve pain originating from the posterior region of the knee. A new type of nerve block known as the IPACK block may be used in conjunction with ACBs as it is designed to inhibit nerve branches innervating this area. In this article, we examine the rationale behind the IPACK procedure, how it is performed, and clinical trials examining its efficacy. RECENT FINDINGS: 5 of the 7 clinical trials examined in this article showed the IPACK + ACB block to show superior efficacy in treating pain following TKR compared to other blocks. These blocks included PMDI+ACB, SPANK+ACB, PAI+ACB, ACB alone, and SCAB. 2 of the 7 clinical trials showed the IPACK + ACB to be less effective in managing patients pain following TKR compared to other blocks which included the CACB and 4 in 1 block. In most instances, the IPACK + ACB showed superior efficacy in managing patients' pain following TKR when compared to other types of nerve blocks. This was determined by measuring usage of opioids, reported postoperative pain, and length of hospital stays following TKR. Thus, we suppose the IPACK block may be used in conjunction with the ACB to effectively reduce patient's pain following TKR.

The Emerging Role of Ketamine in Acute Postoperative Pain Management.

PURPOSE OF REVIEW: Postoperative pain (POP) is among the most unpleasant experiences that patients face after surgery. Interest in and use of N-methyl-D-aspartate (NMDA) receptor antagonists for the management of POP has increased over the years with ketamine being the most popular drug of this class. RECENT FINDINGS: Several randomized controlled trials found that the use of ketamine either alone or in combination with other medications leads to decreased postoperative pain and opioid consumption. However, there are other studies that have not found these benefits. The results as of now suggest that the role of intraoperative ketamine in postoperative pain control varies among different operative procedures. While some studies have shown promise in ketamine's potential use as a postoperative analgesic, there is still a great deal of proposed research and randomized controlled trials needed to deduce the most efficacious and tolerable form and dose of ketamine.

Midazolam nasal spray to treat intermittent, stereotypic episodes of frequent seizure activity: pharmacology and clinical role, a comprehensive review.

An intranasal formulation of midazolam, Nayzilam, has been FDA-approved to treat intermittent, stereotypic episodes of frequent seizure activity. Nayzilam is easy to administer and can quickly treat seizures that occur outside of the hospital. The intra-nasal route of administration allows non-medical personal to administer the drug which makes it more accessible and user-friendly in the event of a seizure. Many studies have indicated quick cessation of seizures with Nayzilam compared to rectal diazepam, which has been the standard of care treatment. Nayzilam has been proven to be safe and effective for acute seizures in children, deeming it a revolutionary alternative in times where intravenous administration is not possible.

Regenerative Medicine: Pharmacological Considerations and Clinical Role in Pain Management.

PURPOSE OF REVIEW: Low back pain affects at least 80% of individuals at some point in their lifetime and is the fifth most common reason for physician visits in the USA. Treatment of an acute episode of LBP generally includes rest, activity modification, physical therapy, NSAIDs, and patient education. RECENT FINDINGS: A small percentage of patients will develop chronic pain lasting > 6 months duration. Platelet-rich plasma (PRP) is one of the main pillars of regenerative medicine, as its release of bioactive proteins supports the aim of RM of restoring the anatomical function in degenerative conditions. Mesenchymal stem cells (MSCs) are multipotent stem cells, multipotent progenitor cells, or marrow stromal cells found in various body tissues, including bone marrow, lung, and adipose tissue. Evidence from well-designed case-control or cohort studies for the use of PRP and MSCs in lumbar facet joint, lumbar epidural, and sacroiliac joint injections is currently described as level IV evidence. PRP and MSCs are used autogenously to help facilitate the healing process, and their injection has been studied in the long-term management of discogenic low back pain. PRP has been compared to steroid injections in the sacroiliac joint for chronic low back pain, with favorable results. MSCs have also been shown to be useful in intervertebral disc regeneration and treatment of chronic low back pain associated with degenerative disc disease. Currently, the price for these treatments is extremely high, and thus the standard of care continues to be steroid injections and other treatments. This could change, however, with more robust data and research on the safety and long-term efficacy of biologics compared to other interventional management.

Novel Local Anesthetics in Clinical Practice: Pharmacologic Considerations and Potential Roles for the Future.

The treatment of pain, both acute and chronic, has been a focus of medicine for generations. Physicians have tried to develop novel ways to effectively manage pain in surgical and post-surgical settings. One intervention demonstrating efficacy is nerve blocks. Single-injection peripheral nerve blocks (PNBs) are usually preferred over continuous PNBs, since they are not associated with longer lengths of stay. The challenge of single injection PNBs is their length of duration, which at present is a major limitation. Novel preparations of local anesthetics have also been studied, and these new preparations could allow for extended duration of action of anesthetics. An emerging preparation of bupivacaine, exparel, uses a multivesicular liposomal delivery system which releases medication in a steady, controlled manner. Another extended-release local anesthetic, HTX-011, consists of a combination of bupivacaine and low-dose meloxicam. Tetrodotoxin, a naturally occurring reversible site 1 sodium channel toxin derived from pufferfish and shellfish, has shown the potential to block conduction of isolated nerves. Neosaxitoxin is a more potent reversible site 1 sodium channel toxin also found in shellfish that can also block nerve conduction. These novel formulations show great promise in terms of the ability to prolong the duration of single injection PNBs. This field is still currently in development, and more researchers will need to be done to ensure the efficacy and safety of these novel formulations. These formulations could be the future of pain management if ongoing research continues to prove positive effects and low side effect profiles.

The Influence of Analgesic Modalities on Postoperative Cancer Recurrence.

The potential for cancer cells to grow and to metastasize depends on complex interactions between inflammatory signals and pathways, immune cells, and elements of the stromal tissue in which they invade. Related to the nature of many cancers, the probability of recurrence can potentially be quite high for some patients. Immunology, lifestyle modifications, timing of disease, genetics, age, gender, and race are only a handful of ways the likelihood of cancer recurrence can be influenced. The quantity, or density, of certain immunological cells or factors, plays a role in the propagation of cancer cells. Opioids are often used in cancer patients for acute postoperative and chronic pain management. While they can produce significant pain relief, the type of analgesic utilized is important, as it may influence cancer propagation. In this regard, certain opioids have been found to increase T regulatory cells while suppressing NK cell function. Morphine may promote tumor neovascularization and expansion. Fentanyl administration significantly diminishes NK-cells and CD8+ cytotoxic T-cells. In a recent meta-analysis, propofol-based anesthesia improved both cancer-free survival and overall survival. COX inhibitors have also shown promise in persevering cancer immune function, as in literature involving ketorolac and celecoxib. In summary, inhaled anesthesia and opioids may contribute to a pro-tumor metastasis environment also known as cancer propagation; whereas propofol and COX inhibitors may provide a better alternative to reduce cancer recurrence and propagation.

Paliperidone 3-Month Injection for Treatment of Schizophrenia: A Narrative Review.

Given the typical age onset of schizophrenia, there are tremendous economic and social impacts that extend beyond the person and their families. One critical determinant of the diseases' impact is the patient's adherence to antipsychotic drug treatment. Approved in 2015 for the treatment of schizophrenia, paliperidone palmitate (Invega Trinza, a 3-month injection, noted as PP3M) is a second-generation long-acting injectable antipsychotic medication. Among the different formulations offered for palmitate paliperidone, including the 1 and 3-month formulations, the longer duration 3-month formulation was better at preventing relapse in schizophrenic patients. To date, different formulations of palmitate paliperidone that have been studied on relapse episodes of schizophrenia include once-daily extended-release oral paliperidone (ORAL paliperidone), once-monthly paliperidone palmitate (PP1M), and once-every-3-months paliperidone palmitate (PP3M). Post-hoc analyses show that patients who were withdrawn from PP1M paliperidone had the least risk of relapse, followed by patients withdrawn from PP3M and patients withdrawn from ORAL paliperidone. PP3M was better at preventing relapse compared to ORAL paliperidone. The results demonstrated that 50% of patients who were withdrawn from ORAL paliperidone, PP1M, or PP3M remained relapse-free for ~2, 6, and 13 months, respectively. Compared to PP1M, PP3M is just as safe and effective and has the added advantage of increased adherence related to a longer dose interval, decreasing the risk of relapse.

Novel Regional Nerve Blocks in Clinical Practice: Evolving Techniques for Pain Management.

This review examines the use of novel US-guided nerve blocks in clinical practice. Erector spinae block is a regional anesthesia technique doing by injecting a local anesthetic among the erector spinae muscle group and transverse processes. The phrenic nerve is a branch of the cervical plexus, arising from the anterior rami of cervical nerves C3, C4, and C5. The quadratus lumborum muscle is located along the posterior abdominal wall. It originates from the transverse process of the L5 vertebral body, the iliolumbar ligament, and the iliac crest. US-guided peripheral nerve procedures have a considerable scope of use, including treating headaches and hiccups to abdominal surgical pain, cesarean sections, musculoskeletal pathologies. These nerve blocks have been an effective addition to clinical anesthesia practice. The use of peripheral nerve blocks has improved postoperative pain, lessened the use of opioids and their potential side effects, and decreased the incidence of sleep disturbance in patients. More research should be done to further delineate the potential benefits of these blocks.

Pharmacological Advances in Opioid Therapy: A Review of the Role of Oliceridine in Pain Management.

Problems with the treatment of acute pain may arise when a patient is opioid-tolerant, such as those on chronic therapy with opioids or opiate replacement therapy, those who misuse opioids, and those who are in recovery. While some of the adverse effects of opioid medications are well known, it is also important to recognize the roles of tolerance and hyperalgesia. Oliceridine can target and modulate a novel µ-receptor pathway. The G protein-biased agonism of oliceridine allows for effective re-sensitization and desensitization of the mu-opioid receptor, which decreases the formation of opioid tolerance in patients. Oliceridine has been demonstrated to be an effective and relatively safe intravenous analgesic for the treatment of postoperative pain and is generally well tolerated with a favorable side effect profile when compared to morphine. As the prevalence of pain increases, it is becoming increasingly important to find safe and effective analgesics.

Adjuvant Drugs for Peripheral Nerve Blocks: The Role of NMDA Antagonists, Neostigmine, Epinephrine, and Sodium Bicarbonate.

The potential for misuse, overdose, and chronic use has led researchers to look for other methods to decrease opioid consumption in patients with acute and chronic pain states. The use of peripheral nerve blocks for surgery has gained increasing popularity as it minimizes peripheral pain signals from the nociceptors of local tissue sustaining trauma and inflammation from surgery. The individualization of peripheral nerve blocks using adjuvant drugs has the potential to improve patient outcomes and reduce chronic pain. The major limitations of peripheral nerve blocks are their limited duration of action and dose-dependent adverse effects. Adjuvant drugs for peripheral nerve blocks show increasing potential as a solution for postoperative and chronic pain with their synergistic effects to increase the duration of action and decrease the required dosage of local anesthetic. N-methyl-d-aspartate (NMDA) receptor antagonists are a viable option for patients with opioid resistance and neuropathic pain due to their affinity to the neurotransmitter glutamate, which is released when patients experience a noxious stimulus. Neostigmine is a cholinesterase inhibitor that exerts its effect by competitively binding at the active site of acetylcholinesterase, which prevents the hydrolysis of acetylcholine and subsequently retaining acetylcholine at the nerve terminal. Epinephrine, also known as adrenaline, can potentially be used as an adjuvant to accelerate and prolong analgesic effects in digital nerve blocks. The theorized role of sodium bicarbonate in local anesthetic preparations is to increase the pH of the anesthetic. The resulting alkaline solution enables the anesthetic to more readily exist in its un-ionized form, which more efficiently crosses lipid membranes of peripheral nerves. However, more research is needed to show the efficacy of these adjuvants for nerve block prolongation as studies have been either mixed or have small sample sizes.

Adjuvant Drugs for Peripheral Nerve Blocks: The Role of Alpha-2 Agonists, Dexamethasone, Midazolam, and Non-steroidal Anti-inflammatory Drugs.

Adjuvant drugs for peripheral nerve blocks are a promising solution to acute postoperative pain and the transition to chronic pain treatment. Peripheral nerve blocks (PNB) are used in the brachial plexus, lumbar plexus, femoral nerve, sciatic nerve, and many other anatomic locations for site-specific pain relief. However, the duration of action of a PNB is limited without an adjuvant drug. The use of non-opioid adjuvant drugs for single-shot peripheral nerve blocks (sPNB), such as alpha-2 agonists, dexamethasone, midazolam, and non-steroidal anti-inflammatory drugs, can extend the duration of local anesthetics and reduce the dose-dependent adverse effects of local anesthetics. Tramadol is a weak opioid that acts as a central analgesic. It can block voltage-dependent sodium and potassium channels, cause serotonin release, and inhibit norepinephrine reuptake and can also be used as an adjuvant in PNBs. However, tramadol's effectiveness and safety as an adjuvant to local anesthetic for PNB are inconsistent. The effects of the adjuvants on neurotoxicity must be further evaluated with further studies to delineate the safety in their use in PNB. Further research needs to be done. However, the use of adjuvants in PNB can be a way to help control postoperative pain.

A Comprehensive Review of Novel Interventional Techniques for Chronic Pain: Spinal Stenosis and Degenerative Disc Disease-MILD Percutaneous Image Guided Lumbar Decompression, Vertiflex Interspinous Spacer, MinuteMan G3 Interspinous-Interlaminar Fusion.

Spinal stenosis is the compression of nerve roots by bone or soft tissue secondary to the narrowing of the spinal canal, lateral recesses, or intervertebral foramina. Spinal stenosis may have acquired or congenital origins. Most cases are acquired and caused by hypertrophy of the ligamentum flavum, enlarged osteophytes, degenerative arthritis, disk herniations, and various systemic illnesses. The ligamentum flavum (LF) is a highly specialized elastic ligament that connects the laminae of the spine and fuses them to the facet joint capsules. There are a number of treatment options available for spinal stenosis. Implants and surgical interventions have grown in popularity recently, and a number of these have been shown to have varying efficacy, including the minimally invasive lumbar decompression (MILD®), Vertiflex®, Coflex® Interlaminar Stabilization, and MinuteMan G3® procedures. Minimally invasive lumbar decompression (MILD®) is a minimally invasive outpatient procedure to treat spinal stenosis related to hypertrophied ligamentum flavum. The Superion® Interspinous Spacer, also known as Vertiflex®, is a titanium implant that is delivered percutaneously to relieve back pain caused by lumbar spinal stenosis. The MinuteMan® is a minimally invasive, interspinous-interlaminar fusion device planned for the temporary fixation of the thoracic, lumbar, and sacral spine, which eventually results in bony fusion. Based on our review of the available current scientific literature, the novel interventions for symptomatic lumbar spinal stenosis, such as the MILD® procedure and the Superion® interspinous spacer, generally appear to be safe and effective. There is a possibility in the future that these interventions could disrupt current treatment algorithms for lumbar spinal stenosis.

Novel Interventional Techniques for Chronic Pain with Minimally Invasive Arthrodesis of the Sacroiliac Joint: (INSITE, iFuse, Tricor, Rialto, and others).

Acute and chronic pain are public health issues that clinicians have been battling for years. Opioid medications have been a treatment option for both chronic and acute pain; however, they can cause unwanted complications and are a major contributor to our present opioid epidemic. The sacroiliac (SI) joint is a common cause of both acute and chronic low back pain. It affects about 15-25% of patients with axial low back pain, and up to 40% of patients with ongoing pain following lumbar fusion. Recent advances in the treatment of SI joint pain have led to the development of a wide variety of SI joint fusion devices. These fusion devices seek to stabilize the joints themselves in order that they become immobile and, in theory, can no longer be a source for pain. This is a minimally invasive procedure aimed to address chronic pain without subjecting patients to lengthy surgery or medications, including opioids with the potential for addiction and abuse. Minimally invasive SI fusion can be performed by a lateral approach (i.e., iFuse, Tricor) or posterior approach (i.e., CornerLoc, LinQ, Rialto). The posterior approach requires the patient to be in the prone position but allows for less disruption of muscles with entry. More data are necessary to determine which fusion system may be best for a particular patient. SI fusion devices are a promising way of treating chronic lower back pain related to the SI joint. This narrative review will discuss various types of SI fusion devices, and their potential use in terms of their safety and efficacy.

Peripheral Nerve Stimulation: A Review of Techniques and Clinical Efficacy.

Chronic pain is a common source of morbidity in many patient populations worldwide. There are growing concerns about the potential side effects of currently prescribed medications and a continued need for effective treatment. Related to these concerns, peripheral nerve stimulation has been regaining popularity as a potential treatment modality. Peripheral nerve stimulation components include helically coiled electrical leads, which direct an applied current to afferent neurons providing sensory innervation to the painful area. In theory, the applied current to the peripheral nerve will alter the large-diameter myelinated afferent nerve fibers, which interfere with the central processing of pain signals through small-diameter afferent fibers at the level of the spinal cord. Multiple studies have shown success in the use of peripheral nerve stimulation for acute post-surgical pain for orthopedic surgery, including post total knee arthroplasty and anterior cruciate ligament surgery, and chronic knee pain. Many studies have investigated the utility of peripheral nerve stimulation for the management of chronic shoulder pain. Peripheral nerve stimulation also serves as one of the potential non-pharmacologic therapies to treat back pain along with physical therapy, application of transcutaneous electrical neurostimulation unit, radiofrequency ablation, epidural steroid injections, permanently implanted neurostimulators, and surgery. Studies regarding back pain treatment have shown that peripheral nerve stimulation led to significant improvement in all pain and quality-of-life measures and a reduction in the use of opioids. Further studies are needed as the long-term risks and benefits of peripheral nerve stimulation have not been well studied as most information available on the effectiveness of peripheral nerve stimulation is based on shorter-term improvements in chronic pain.

Brexpiprazole for the Treatment of Schizophrenia and Major Depressive Disorder: A Comprehensive Review of Pharmacological Considerations in Clinical Practice.

Mood and psychotic disorders are a group of illnesses that affect behavior and cognition. Schizophrenia is characterized by positive symptoms, such as delusions and hallucinations, as well as negative symptoms. Major depressive disorder (MDD) is a mood disorder that affects the patient's emotions, energy, and motivation. Brexpiprazole works as a partial agonist at serotonin 5-hydroxytryptamine1A and dopamine D2 receptors and an antagonist at serotonin 5-hydroxytryptamine2A. Schizophrenia and MDD have a wide range of risk factors, both biological and environmental. Third generation antipsychotics, which include brexpiprazole, are the latest group of drugs to reach the market, demonstrating efficacy and tolerability. Patients with acute schizophrenia have responded well to brexpiprazole. In this regard, in patients who have MDD plus anxiety symptoms, brexpiprazole can be effective as an adjunctive therapy and can reduce anxiety symptoms. In summary, brexpiprazole has proved to be an effective alternative to typical or first and second-generation atypical antipsychotics.

Management of Lower Extremity Pain from Chronic Venous Insufficiency: A Comprehensive Review.

PURPOSE OF REVIEW: Chronic venous insufficiency is found to some extent in a large proportion of the world's population, especially in the elderly and obese. Despite its prevalence, little research has been pursued into this pathology when compared to similarly common conditions. Pain is often the presenting symptom of chronic venous insufficiency and has significant deleterious effects on quality of life. This manuscript will describe the development of pain in chronic venous insufficiency, and will also review both traditional methods of pain management and novel advances in both medical and surgical therapy for this disease. RECENT FINDINGS: Pain in chronic venous insufficiency is a common complication which remains poorly correlated in recent studies with the clinically observable extent of disease. Although lifestyle modification remains the foundation of treatment for pain associated with chronic venous sufficiency, compression devices and various pharmacologic agents have emerged as safe and effective treatments for pain in these patients. In patients for whom these measures are insufficient, recently developed minimally invasive vascular surgical techniques have been shown to reduce postsurgical complications and recovery time, although additional research is necessary to characterize long-term outcomes of these procedures. This review discusses the latest findings concerning the pathophysiology of pain in chronic venous insufficiency, conservative and medical management, and surgical strategies for pain relief, including minimally invasive treatment strategies.

Supraclavicular vs. Infraclavicular Brachial Plexus Nerve Blocks: Clinical, Pharmacological, and Anatomical Considerations.

Peripheral nerve blocks (PNB) have become standard of care for enhanced recovery pathways after surgery. For brachial plexus delivery of anesthesia, both supraclavicular (SC) and infraclavicular (IC) approaches have been shown to require less supplemental anesthesia, are performed more rapidly, have quicker onset time, and have lower rates of complications than other approaches (axillary, interscalene, etc.). Ultrasound-guidance is commonly utilized to improve outcomes, limit the need for deep sedation or general anesthesia, and reduce procedural complications. Given the SC and IC approaches are the most common approaches for brachial plexus blocks, the differences between the two have been critically evaluated in the present manuscript. Various studies have demonstrated slight favorability towards the IC approach from the standpoint of complications and safety. Two prospective RCTs found a higher incidence of complications in the SC approach - particularly Horner syndrome. The IC method appears to support a greater block distribution as well. Overall, both SC and IC brachial plexus nerve block approaches are the most effective and safe approaches, particularly under ultrasound-guidance. Given the success of the supraclavicular and infraclavicular blocks, these techniques are an important skill set for the anesthesiologist for intraoperative anesthesia and postoperative analgesia.

A Comprehensive Review of Alternative Therapies for the Management of Chronic Pain Patients: Acupuncture, Tai Chi, Osteopathic Manipulative Medicine, and Chiropractic Care.

INTRODUCTION: Non-pharmacologic alternative therapies for pain have been around for a long time, some for hundreds of years. They have been used throughout history to treat many issues. RECENT FINDINGS: Currently, alternative medicine is most frequently used to treat musculoskeletal pain, and between 59 and 90% of patients utilizing alternative therapies for chronic pain claimed they were helpful and can serve as an effective adjunctive for the treatment of chronic pain. Some examples of alternative therapies that will be discussed in this review include acupuncture, tai chi, osteopathic manipulation, and chiropractic care. Acupuncture, traditionally a Chinese practice, is becoming more popular across the world to attempt to relieve pain. It involves the placement of thin needles at various points in the body. The efficacy of acupuncture for pain is heavily debated. More research and discussion are necessary to determine the exact role it plays in the treatment of chronic pain. Tai chi is also a traditional Chinese practice that is often used as a form of meditation and for potential health benefits. Tai chi involves a series of complex movements such as squatting combined with deep breathing to achieve relaxation and pain reduction. Osteopathic manipulative treatment (OMT) is a technique used by both osteopathic physicians (DO) as well as other health professionals to manage a wide range of conditions in any given patient. The technique involves utilization and manipulation of the musculoskeletal system to achieve potential health benefits. OMT has been used as therapy for many issues but is commonly used for pain conditions. Alternative therapies may serve as an effective adjunctive treatment modality for the management of chronic pain conditions. There has been a tremendous amount of research dictating the effectiveness of alternative therapies for chronic pain management. The purpose of this review is to provide a comprehensive evidence-based update of alternative therapy used for the management of chronic pain conditions.

Neuropathic Pain and Sickle Cell Disease: a Review of Pharmacologic Management.

PURPOSE OF REVIEW: Sickle cell disease (SCD) remains among the most common and severe monogenic disorders present in the world today. Although sickle cell pain has been traditionally characterized as nociceptive, a significant portion of sickle cell patients has reported neuropathic pain symptoms. Our review article will discuss clinical aspects of SCD-related neuropathic pain, epidemiology of neuropathic pain among individuals with SCD, pain mechanisms, and current and future potential pharmacological interventions. RECENT FINDINGS: Neuropathic pain in SCD is a complicated condition that often has a lifelong and significant negative impact on life; therefore, improved pain management is considered a significant and unmet need. Neuropathic pain mechanisms are heterogeneous, and the difficulty in determining their individual contribution to specific pain types may contribute to poor treatment outcomes in this population. Our review article outlines several pharmacological modalities which may be employed to treat neuropathic pain in SCD patients.

The role of regional anesthesia in the propagation of cancer: A comprehensive review.

New cancer incidences worldwide will eclipse 18 million in 2019, with nearly 10 million cancer-related deaths. It is estimated that in the United States, almost 40% of individuals will be diagnosed with cancer in their lifetime. Surgical resection of primary tumors remains a cornerstone of cancer treatment; however, the surgical process can trigger an immune-suppressing sympathetic response, which promotes tumor growth of any residual cancerous cells post surgery. Regional and local anesthesia have become staples of anesthesia and analgesia during and after surgery. Recently, much evidence in the form of retrospective and prospective studies has come to light regarding the protective, antitumor properties of anesthetic and analgesic agents across a wide variety of cancers and patient demographics. It is believed that by blocking afferent pain signals, the body does not mount the sympathetic response that contributes to the perpetuation of disease after surgical treatment. This review, therefore, investigates these studies as they pertain to the treatment and outcomes of cancers treated surgically to elucidate the role of regional anesthesia in the propagation of cancer.