Journal of Artificial Organs最新文献

Cardiac surgery patients are potentially exposed to an acute inflammatory host response with a huge release of both pro- and anti-inflammatory cytokines both through intrinsic (e.g., tissue damage, endothelial injury) and extrinsic (e.g., anesthesia, extracorporeal circuits) mechanisms. Current standard of care therapy includes several invasive supportive treatments such as mechanical ventilation, continuous renal replacement therapy, ECMO, and/or cardiopulmonary bypass which may be responsible for an important inflammatory response. The inflammatory cytokine levels and hemodynamic status following these artificial treatments along with the current standard therapy are not always well controlled and may lead to worsened acute clinical conditions with prolonged in-hospital length of stay and increased mortality. In these settings, the administration of hemadsorption therapy with CytoSorb® has been supported by the successful results in several clinical studies as it has shown improvement of both the inflammatory profile and the hemodynamic vascular status of the patients. Therefore, in this narrative review, we summarized and discussed the current scientific literature on the role of CytoSorb^® treatment in case of cardiac surgery. According to the current evidences, the raised inflammatory levels and both inotropic and vasopressor requests in cardiac surgery patients need more tailored therapies and, in this contest, the hemadsorption with CytoSorb^® could play a pivotal role, especially on heart transplant patients. Furthermore, CytoSorb is currently the only hemadsorption sorbent authorized and efficiently applied for removing anticoagulant agents such as ticagrelor or rivaroxaban in patients undergoing cardiac surgery, to reduce perioperative bleeding complications and should be considered in high-risk patients.

The use of veno-venous extracorporeal membrane oxygenation (VV-ECMO) has become increasingly prevalent, particularly in respiratory disease pandemics such as H1N1-influenza and SARS-CoV-2. This surge has emphasized the importance of clear therapy recommendations, improved accessibility to ECMO technology, established ECMO teams, and structured networks to ensure access to specialized care throughout the course of the disease for patients with severe ARDS. Although the initiation criteria for VV-ECMO are well defined, treatment strategies while on ECMO regarding e.g., ventilator management or ECMO weaning strategies remain variable and with lack of consensus. NAVA (Neurally Adjusted Ventilatory Assist), as an assisted mechanical ventilation modality, offers real-time electromyographic feedback, which has been shown to enhance prolonged weaning processes from mechanical ventilation. We present a case of penetrating thoracic trauma complicated by ARDS, successfully managed with VV-ECMO. NAVA was employed to monitor and facilitate ECMO. This approach integrates ECMO weaning with ventilation settings, considering both gas exchange lung function, such as carbon dioxide removal, and respiratory mechanics in the form of neuromuscular coupling. This is a new approach to VV-ECMO weaning. More research is planned to validate the efficacy of this method in conjunction with additional parameters, such as diaphragm activity evaluated sonographically in a randomized design. This case underscores the potential of NAVA in VV-ECMO weaning, offering a promising avenue for optimizing patient care and outcomes.

This study clarifies the reagent preparation and administration conditions that lead to precipitation when nafamostat mesylate salt (NM) solution is mixed with dialysate. The objective is to elucidate the mechanism of precipitation. It was observed that the Carbostar^® dialysate forms a precipitate immediately after mixing with the NM solution, whereas Kindaly^® and Subpac^® dialysates form a precipitate after approximately 30 min. This variance is attributed to the pH adjusters used: citric acid for Carbostar^®, acetic acid for Kindaly^®, and hydrochloric acid for Subpac^®. As trivalent negative ions, citrate ions promote faster precipitation compared to acetic acid and hydrochloric acid, which are monovalent ions. Nafamostat acetate and nafamostat chloride salts are soluble, while nafamostat citrate is poorly soluble, leading to differences in precipitation timing. The bicarbonate ion's pK_a value is 6.1, meaning precipitation does not occur if the pH is lowered below 6.1 using acetic acid or hydrogen chloride as pH adjusters. The solubility product of nafamostat bicarbonate is 8.1 × 10^-7 (mol/L)³, making precipitation inevitable under dialysis conditions ([nafamostat²⁺] = 5 mg/mL (9.2 mM), [HCO₃^-] = 35 mM). The primary precipitate component is nafamostat bicarbonate salt. Although NM is initially water-soluble, it undergoes chemical transformation into a poorly soluble salt through ion exchange from mesylate ions to bicarbonate ions within the dialysate, resulting in precipitation. Based on these findings, we propose conditions to avoid precipitation.

Central vein stenosis (CVS) is a complication primarily affecting chronic hemodialysis patients, frequently resulting in vascular access dysfunction and decreased dialysis efficacy. While CVS has a variable mortality rate, its impact on dialysis access is profound, including arm edema, facial swelling, and venous hypertension. We describe the prevalence, clinical presentation, and treatment outcomes of CVS for vascular access in hemodialysis patients. We conducted a prospective observational study from July 2023 to June 2024, on patients undergoing maintenance hemodialysis (MHD) at a tertiary care center in South India who had CVS detected by CT Venography. Demographic information, comorbidity, access type, stenosis location, clinical presentation, treatment, and outcome data were collected and analyzed. Of the 152 patients on MHD, 20 (13.1%) had CVS. Of them, 7 patients were on tunneled catheter and 13 were on AVF. Arm edema (47%) was the most common symptom, followed by face swelling (29%) and prolonged bleeding (11%) from arteriovenous fistula post dialysis. The brachiocephalic vein (BCV) was the most common site of stenosis in 65% of patients. Angioplasty was performed in (N = 9) nine patients with a primary success rate of 66% and a six-month patency of 44.4%. In the remaining eleven (N = 11) four patients (20%) transitioned to CAPD, three (15%) had new access of which two had femoral catheter inserted and other one had new AVF creation done and two (10%) continued dialysis via same access. Mortality occurred in two patients (10%) due to pulmonary edema. The Prevalence of CVS in our study population was 13.1%. Six-month primary patency rate among those who underwent intervention was 44.4%. Vascular access had to be terminated in 55%.

Cardiac xenotransplantation utilizing genetically modified pigs presents a promising avenue for treating end-stage heart failure, a leading cause of mortality worldwide. This paper delineates the current landscape of heart failure treatment in Japan, emphasizing the limitations of existing therapies such as heart transplantation and implantable left ventricular assist devices. It discusses the history and advancements in the development of genetically modified pigs for xenotransplantation, highlighting recent breakthroughs and challenges. The manuscript also addresses the specific challenges facing the implementation of xenotransplantation in Japan, including the selection of suitable genetically modified pigs, ensuring organ safety, patient selection criteria, transplantation protocols, and immunosuppression strategies. Drawing from international experiences and ongoing research efforts, the paper emphasizes the potential of xenotransplantation while acknowledging the hurdles that must be overcome for widespread clinical adoption.

Extracorporeal membrane oxygenation (ECMO) is an established technique for managing severe cardiorespiratory failure. However, it is invasive and requires profound analgo-sedation during initiation and often throughout the therapy. Managing sedation in venovenous (VV) ECMO patients is particularly challenging due to the impact of ECMO circuits on pharmacokinetics and specific patient requirements. This can lead to unpredictable sedative effects and require multiple drugs at higher doses. Additionally, sedation is usually managed with traditional scoring methods, which are subjective and invalid during neuromuscular blockade. These uncertainties may impact outcomes. Recent clinical practice increasingly focuses on reducing sedation to enable earlier physiotherapy and mobilisation, particularly in patients awaiting transplants or receiving mechanical circulatory support. In this context, processed electroencephalogram-based (pEEG) sedation monitoring might be promising, having shown benefits in general anaesthesia and intensive care. However, the technology has limitations, and its benefits in ECMO practice have yet to be formally evaluated. This review provides insights into the challenges of ECMO sedation, including pharmacokinetics, unique ECMO requirements, and the implications of inadequate sedation scores. Finally, it includes a brief overview of the practicality and limitations of pEEG monitoring during VV-ECMO, highlighting a significant research gap.

This review traces the evolution of centrifugal blood pumps in mechanical circulatory support (MCS) systems. Initially met with concerns over blood damage and thrombus formation, centrifugal pumps have become crucial components in ventricular assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) due to their simplified drive mechanisms and adaptability. This paper outlines three generations of centrifugal pump development: first-generation pumps with sealing components, second-generation pumps utilizing pivot bearings, and third-generation pumps employing contactless bearings. Each iteration addressed previous limitations, particularly regarding thrombus formation and durability. Current regulatory challenges surrounding the duration of pump use in MCS are examined, highlighting the discrepancy between approved usage times and clinical needs. This paper notes ongoing efforts to extend approved use periods, citing examples of pumps cleared for extended use in various jurisdictions. This historical perspective provides insights into the technological advancements that have enhanced the safety, efficacy, and durability of centrifugal blood pumps in MCS applications.

Abel JJ, Rowntree LG and Turner BB (Baltimore Trio) proposed the concept of vividiffusion and developed a vividiffusion apparatus in 1912. In a 1914 paper, they laid out the most important rule of device design. We named this rule an ART law taken from the initials of the Baltimore Trio. The ART law means that a blood purification device with a shape that can secure as large a dialysis membrane area as possible for as small a volume of blood filling as possible will achieve high dialysis performance. Rather than using 8 mm inner diameter collodion tubes in the original vividiffusion apparatus, the solution to the device shape that fits this rule is to hold down the tube from both top and bottom to make it as flat as possible, or if it is a flat membrane, to bring two flat membranes as close together as possible, and in the case of tubes and hollow fibers, to make their inner diameter as small as possible of approximately 200 μm. In other words, the dialysis performance is greatly improved by narrowing the blood flow path. This is exactly the ART law, predicting the shape of today's blood purification devices.

We tested the hypothesis that disseminated intravascular coagulation (DIC) predicts a poor prognosis in patients with out-of-hospital cardiac arrest (OHCA) treated with veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Fifty-seven patients with cardiogenic OHCA who immediately underwent VA-ECMO upon admission to the emergency department were divided into 27 non-DIC and 30 DIC patients. DIC scores were calculated on admission and 24 h later (day 1). The primary outcome measure was the all-cause in-hospital mortality. The basic characteristics did not differ between the two groups; however, patients with DIC showed higher in-hospital mortality rates. Receiver operating characteristic curve analysis showed a moderate predictive ability of DIC scores on day 1 for in-hospital mortality. A lower probability of survival was observed in patients with DIC. The adjusted odds ratio for DIC on day 1 of in-hospital death was 5.67, confirmed by the adjusted hazard ratio of 3.472. The results indicate an association between DIC diagnosis 24 h following VA-ECMO induction for OHCA and poor outcome in these patients.

This study aimed to evaluate the prognostic significance of the levels of admission hematocrit (HCT) and the changes in the initial blood urea nitrogen (BUN) levels in predicting the efficacy of blood purification (BP) therapy in ameliorating severe acute pancreatitis (SAP) patients at admission. A retrospective study was conducted on 139 SAP patients from the People's Hospital of Guangxi Zhuang Autonomous Region from 2013 to 2022 and the data retrieved from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database for 346 SAP patients. The patients were stratified based on their HCT0 levels at admission; HCT < 44% (n = 93) and HCT ≥ 44% (n = 46) and ΔBUN levels within the first 24 h post-admission; ΔBUN ≤ 0 (n = 78) and ΔBUN > 0 (n = 61). Propensity score matching (PSM) was performed on factors such as age and gender to control for differences among the strata. The clinical outcomes of the patients receiving or not receiving BP therapy were compared based on the mentioned criteria. Patients with HCT0 ≥ 44%, who were treated with BP showed no significant difference in the 28-day mortality. However, a significant increase in hospital expenses and prolonged ICU stays was observed (P < 0.05). Conversely, patients with ΔBUN ≤ 0 who received BP therapy demonstrated relatively high 28-day mortality rates, prolonged ICU stays, increased hospital expenses, and low SOFA scores (P < 0.05). The analyses of MIMIC-IV database data corroborated these findings. The predictive efficacy of BP therapy in SAP patients was significantly influenced by the changes in BUN levels at 24 h post-admission compared to the initial levels of HCT on admission. Selecting SAP patients suitable for BP treatment should be based on the changes in BUN levels to enhance effective therapeutic outcomes.