A Comprehensive Review of Lemborexant to Treat Insomnia.

Purpose of Review: This is a comprehensive review of the literature regarding Lemborexant for the treatment of insomnia. It covers the background and management of insomnia and then reviews the body of existing evidence evaluating the use of Lemborexant for this purpose. Recent Findings: Insomnia leads to significant decreased in quality of life and economic burden due to decreased workplace performance and increased health care costs. Insomnia manifests as a single common pathway of hyperarousal due to a highly complex network of interactions between activation of the sympathetic system and the endocrine system. Lemborexant is a dual orexin 1/2 antagonist that blocks cortical arousal and promotes sleep state transition. Lemborexant was approved by the FDA in 2019 for use in insomnia. It belongs to a class of orexin neuropeptide inhibitors that is growing in popular clinical application. Summary: Insomnia is a crippling disorder of the sleep wake cycle that drives significant morbidity and mortality in the United States. It carries a high societal and economic toll due to direct and indirect effects to the healthcare system. Lemborexant is a new addition to the orexin antagonist class of drugs that already includes Almorexant and Suvorexant that has superior pharmacokinetic properties. While Lemborexant does have a mild side effect profile, its clinical safety and efficacy make it a promising insomnia drug of the future.

Supporting the right ventricle in postcardiotomy renal dysfunction: A case series.

Postcardiotomy RV dysfunction is an under-recognized cause of acute kidney injury (AKI). Insertion of a percutaneous right ventricular assist device (RVAD) reduces central venous hypertension and congestive nephropathy by augmenting cardiac output. In selected patients, percutaneous RVAD insertion may improve renal function and obviate the need for long-term dialysis.

Adhered ECMO cannula in COVID-19 related severe acute respiratory failure.

BACKGROUND: Crescent cannula adhesion in the setting of COVID-19 respiratory failure requiring extracorporeal membrane oxygenation (ECMO) support is a novel complication. The objective of this case presentation is to highlight this rare complication and to explore potential predisposing factors and our management strategies. CASE PRESENTATION: We present the case of a 25 y.o. patient with COVID-19 respiratory failure requiring ECMO support for 16-days in which a 32 Fr crescent cannula became adherent to the SVC and proximal jugular vein. Attempts to remove the cannula at the bedside failed due to immobility of the cannula. Ultrasound of the right neck was unremarkable, so he was taken to the hybrid OR where both TEE and fluoroscopy were unrevealing. An upper sternotomy was performed, and the superior vena cava and proximal jugular vein were dissected revealing a 2 cm segment of the distal SVC and proximal jugular vein that was densely sclerosed and adherent to the cannula. The vessel was opened across the adherent area at the level of the innominate vein and the cannula was then able to be withdrawn. The patient suffered no ill effects and had an unremarkable recovery to discharge. CONCLUSIONS: To date, there have been no reports of crescent cannula adhesion related complications. In patients with COVID-19 respiratory failure requiring ECMO, clinicians should be aware of widespread hypercoagulability and the potential of unprovoked, localized venous sclerosis and cannula adhesion. We report our technique of decannulation in the setting of cannula adhesion and hope that presentation will shed further light on this complication allowing clinicians to optimize patient care.

Thoracoabdominal Normothermic Regional Perfusion for Cardiac Procurement.

In donation after circulatory death donors, warm ischemia time is a significant threat to successful cardiac transplantation. The ability to perfuse these organs during the minutes after death, until cardiac evaluation is completed to satisfaction, is crucial in limiting total warm ischemic time. Thoracoabdominal normothermic regional perfusion (TANRP) has emerged as a promising strategy for recovering and monitoring these hearts. We propose a series of clinical practice pearls that we follow for all donation after circulatory death procurements to streamline the process of setting up a TANRP circuit and ensuring all team members present at time procurement are familiar with the procedure. Bicaval cannulation is achieved via the abdomen for aortic cannulation, and via the chest for right atrial cannulation, avoiding deairing maneuvers and providing the shortest possible duration from incision to initiation of cardiopulmonary bypass. Here, we describe a series of practice techniques which we have utilized in our early experience with TANRP.

Sarcoplasmic Reticulum from Horse Gluteal Muscle Is Poised for Enhanced Calcium Transport.

We have analyzed the enzymatic activity of the sarcoplasmic reticulum (SR) Ca2+-transporting ATPase (SERCA) from the horse gluteal muscle. Horses are bred for peak athletic performance yet exhibit a high incidence of exertional rhabdomyolysis, with elevated levels of cytosolic Ca2+ proposed as a correlative linkage. We recently reported an improved protocol for isolating SR vesicles from horse muscle; these horse SR vesicles contain an abundant level of SERCA and only trace-levels of sarcolipin (SLN), the inhibitory peptide subunit of SERCA in mammalian fast-twitch skeletal muscle. Here, we report that the in vitro Ca2+ transport rate of horse SR vesicles is 2.3 ± 0.7-fold greater than rabbit SR vesicles, which express close to equimolar levels of SERCA and SLN. This suggests that horse myofibers exhibit an enhanced SR Ca2+ transport rate and increased luminal Ca2+ stores in vivo. Using the densitometry of Coomassie-stained SDS-PAGE gels, we determined that horse SR vesicles express an abundant level of the luminal SR Ca2+ storage protein calsequestrin (CASQ), with a CASQ-to-SERCA ratio about double that in rabbit SR vesicles. Thus, we propose that SR Ca2+ cycling in horse myofibers is enhanced by a reduced SLN inhibition of SERCA and by an abundant expression of CASQ. Together, these results suggest that horse muscle contractility and susceptibility to exertional rhabdomyolysis are promoted by enhanced SR Ca2+ uptake and luminal Ca2+ storage.

Acquired tracheomalacia due to aortic aneurysm managed with venopulmonary extracorporeal membrane oxygenation for perioperative support.

Extracorporeal membrane oxygenation (ECMO) has diverse applications. In the present report, we have described a case of tracheomalacia from a thoracic aortic aneurysm causing respiratory failure. Total arch replacement with reverse frozen elephant trunk grafting was performed. Perioperative ECMO support was accomplished with venopulmonary artery ECMO. This strategy allowed for preoperative oxygenation support, venous drainage during cardiopulmonary bypass, and postoperative support without cannula exchanges. Our patient required ECMO support for 12 days postoperatively. We have illustrated a unique case of acquired tracheomalacia but also an ECMO cannulation strategy allowing for preoperative oxygenation, seamless transition to cardiopulmonary bypass, and postoperative support.

Purification of sarcoplasmic reticulum vesicles from horse gluteal muscle.

We have analyzed protein expression and enzyme activity of the sarcoplasmic reticulum Ca2+-transporting ATPase (SERCA) in horse gluteal muscle. Horses exhibit a high incidence of recurrent exertional rhabdomyolysis, with myosolic Ca2+ proposed, but yet to be established, as the underlying cause. To better assess Ca2+ regulatory mechanisms, we developed an improved protocol for isolating sarcoplasmic reticulum (SR) vesicles from horse skeletal muscle, based on mechanical homogenization and optimized parameters for differential centrifugation. Immunoblotting identified the peak subcellular fraction containing the SERCA1 protein (fast-twitch isoform). Gel analysis using the Stains-all dye demonstrated that calsequestrin (CASQ) and phospholipids are highly enriched in the SERCA-containing subcellular fraction isolated from horse gluteus. Immunoblotting also demonstrated that these horse SR vesicles show low content of glycogen phosphorylase (GP), which is likely an abundant contaminating protein of traditional horse SR preps. The maximal Ca2+-activated ATPase activity (Vmax) of SERCA in horse SR vesicles isolated using this protocol is 5‒25-fold greater than previously-reported SERCA activity in SR preps from horse skeletal muscle. We propose that this new protocol for isolating SR vesicles will be useful for determining enzymatic parameters of horse SERCA with high fidelity, plus assessing regulatory effect of SERCA peptide subunit(s) expressed in horse muscle.