Spinal Cord Stimulation for Post Total Knee Replacement Pain: A Case Series

It is not uncommon for orthopedic patients to experience pain following a total knee replacement (TKR). Use of oral pain medications, nerve blocks, and periarticular injections are implemented to provide multimodal analgesia and to reduce postoperative chronic pain. Spinal cord stimulation (SCS) can also be used to control pain in patients who are refractory to conservative measures. Few studies have explored this possibility for patients with chronic pain status post TKR. We present three cases that demonstrate the effectiveness of SCS in this challenging patient population.

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.

Cortical morphometric correlational networks associated with cognitive deficits in first episode schizophrenia

Schizophrenia (SCZ) is a chronic cognitive and behavioral disorder associated with abnormal cortical activity during information processing. Several brain structures associated with the seven performance domains evaluated using the MATRICS (Measurement and Treatment Research to Improve Cognition in Schizophrenia) Consensus Cognitive Battery (MCCB) have shown cortical volume loss in first episode schizophrenia (FES) patients. However, the relationship between morphological organization and MCCB performance remains unclear. Therefore, in the current observational study, high-resolution structural MRI scans were collected from 50 FES patients, and the morphometric correlation network (MCN) using cortical volume was established to characterize the cortical pattern associated with poorer MCCB performance. We also investigated topological properties, such as the modularity, the degree and the betweenness centrality. Our findings show structural volume was directly and strongly associated with the cognitive deficits of FES patients in the precuneus, anterior cingulate, and fusiform gyrus, as well as the prefrontal, parietal, and sensorimotor cortices. The medial orbitofrontal, fusiform, and superior frontal gyri were not only identified as the predominant nodes with high degree and betweenness centrality in the MCN, but they were also found to be critical in performance in several of the MCCB domains. Together, these results suggest a widespread cortical network is altered in FES patients and that performance on the MCCB domains is associated with the core pathophysiology of SCZ.

HTX-011 (bupivacaine and meloxicam) for the prevention of postoperative pain - clinical considerations

HTX-011 is an extended-release, dual-acting local anesthetic consisting of bupivacaine (sodium-channel blocker) and low-dose meloxicam (non-steroidal anti-inflammatory drug [NSAID]) applied needle-free during surgery. Introducing low-dose meloxicam addresses the limited efficacy of liposomal bupivacaine in acidic inflamed tissues and allows enhanced analgesic effects over three days. It has great promise to be an extremely effective postoperative pain regimen and produce an opioid-free surgical recovery, as it has consistently significantly reduced pain scores and opioid consumption through 72 h. This manuscript provides an updated, concise narrative review of the pharmacology, clinical efficacy, safety and tolerability of this drug and its applications to prevent postoperative pain.

Folic Acid Supplementation in Patients with Elevated Homocysteine Levels

Introduction

Folic acid is the most important dietary determinant of homocysteine (Hcy). Hcy serves as a critical intermediate in methylation reactions. It is created from methionine and either converted back to methionine or transformed into cysteine. This process is aided through several enzymes and three vitamins, folic acid, B12, and B6. Daily supplementation with 0.5–5.0 mg of folic acid typically lowers plasma Hcy levels by approximately 25%. Hyperhomocysteinemia is a known risk factor for coronary artery disease. In this regard, elevated levels of Hcy have been found in a majority of patients with vascular disease.

Methods

A literature review of folic acid supplementation for various disease states including cardiovascular disease was conducted. This article is based on previously conducted studies and does not contain any studies with human participants or animals performed by any of the authors.

Results

In this review, we discuss the biochemistry of folic acid, Hcy biosynthesis, Hcy and hydrogen sulfide bioavailability, pathogenesis of hyperhomocysteinemia and its role as a risk factor for disease, and treatment studies with folic acid supplementation in disease states.

Conclusion

Folic acid supplementation should be recommended to any patient who has an elevated Hcy level, and this level should be measured and treated at an early age, since folic acid is easily obtained and may likely reduce vascular disease and other deleterious pathologic processes in high-risk populations.

Chronic pain and substance abuse disorders: Preoperative assessment and optimization strategies

There is an ever-increasing number of opioid users among chronic pain patients and safely managing them can be challenging for surgeons, anesthesiologists, pain experts, and addiction specialists. Healthcare providers must be familiar with phenomena typical of opioid users and abusers, including tolerance, physical dependence, hyperalgesia, and addiction. Insufficient pain management is very common in these patients. Patient-centered preoperative communication is integral to setting realistic expectations for postoperative pain, developing successful nonopioid analgesic regimens, minimizing opioid consumption during the postoperative period, and decreasing the number of opioid pills at the risk of diversion. Preoperative evaluation should identify comorbidities and identify risk factors for substance abuse and withdrawal. Intraoperative and postoperative strategies can ensure safe and effective pain management and minimize the potential for morbidity and mortality in this high-risk patient population.

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.

Ubiquitin-activating/conjugating activity of TAFII250, a mediator of activation of gene expression in Drosophila

Ubiquitination of histones has been linked to the complex processes that regulate the activation of eukaryotic transcription. However, the cellular factors that interpose this histone modification during the processes of transcriptional activation are not well characterized. A biochemical approach identified the Drosophila coactivator TAFII250, the central subunit within the general transcription factor TFIID, as a histone-specific ubiquitin-activating/conjugating enzyme (ubac). TAFII250 mediates monoubiquitination of histone H1 in vitro. Point mutations within the putative ubac domain of TAFII250 abolished H1-specific ubiquitination in vitro. In the Drosophila embryo, inactivation of the TAFII250 ubac activity reduces the cellular level of monoubiquitinated histone H1 and the expression of genes targeted by the maternal activator Dorsal. Thus, coactivator-mediated ubiquitination of proteins within the transactivation pathway may contribute to the processes directing activation of eukaryotic transcription.

Mesoderm-determining transcription in Drosophila is alleviated by mutations in TAF(II)60 and TAF(II)110

In Drosophila, a coordinate interplay between the Rel transcription factor Dorsal and the basic Helix-Loop-Helix transcription factor Twist initiates mesoderm formation by activating the zygotic expression of mesoderm-determining genes. Here, we show that TBP-associated-factors (TAF(II)s) within the basal transcription factor TFIID mediate transcriptional activation by Dorsal and Twist. Dorsal interacts with TAF(II)110 and TAF(II)60, while Twist contacts TAF(II)110. The TAF(II):activator interactions mediate simple and synergistic transactivation by Dorsal and Twist in vitro. Mutations in TAF(II)60 or TAF(II)110 alleviate the transcription of Dorsal and Twist target genes. Gene dosage assays imply that an interplay of Dorsal and Twist with TAF(II)110 is critically required for the activation of mesoderm-determining gene expression in the Drosophila embryo. The results provide evidence that TAF(II)-subunits within the TFIID complex play an important role during the molecular events leading to initiation of mesoderm formation in Drosophila.