Journal of Artificial Organs最新文献

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.

Neutrophil extracellular traps (NETs) were detected in blood samples and in cellular deposits of oxygenator membranes during extracorporeal membrane oxygenation (ECMO) therapy and may be responsible for thrombogenesis. The aim was to evaluate the effect of the base material of gas fiber (GF, polymethylpentene) and heat exchange (HE) membranes and different antithrombogenic coatings on isolated granulocytes from healthy volunteers under static culture conditions. Contact of granulocytes with membranes from different ECMO oxygenators (with different surface coatings) and uncoated-GFs allowed detection of adherent cells and NETotic nuclear structures (normal, swollen, ruptured) using nuclear staining. Flow cytometry was used to identify cell activation (CD11b/CD62L, oxidative burst) of non-adherent cells. Uncoated-GFs were used as a reference. Within 3 h, granulocytes adhered to the same extent on all surfaces. In contrast, the ratio of normal to NETotic cells was significantly higher for uncoated-GFs (56-83%) compared to all coated GFs (34-72%) (p < 0.001) with no difference between the coatings. After material contact, non-adherent cells remained vital with unchanged oxidative burst function and the proportion of activated cells remained low. The expression of activation markers was independent of the origin of the GF material. In conclusion, the polymethylpentene surfaces of the GFs already induce NET formation. Antithrombogenic coatings can already reduce the proportion of NETotic nuclei. However, it cannot be ruled out that NET formation can induce thrombotic events. Therefore, new surfaces or coatings are required for future ECMO systems and long-term implantable artificial lungs.

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.

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.

Using autologous orthotopic liver transplantation (AOLT) model in rats, the effect of lipid reactive oxygen species (L-ROS) inhibitor Ferrostain-1 on ferroptosis signal pathway was observed to determine whether ferroptosis occurred in rat liver injury after cold ischemia-reperfusion (I/R). Thirty-two healthy adult SPF male SD rats, 8 ~ 10 weeks old, weight 240 ~ 260 g, were divided into four groups by the method of random number table (n = 8): sham group, I/R group, I/R + Fer-1 group, I/R + DFO group. In the I/R + Fer-1 group, ferristatin-1(5 mg /kg) was intraperitoneally injected 30 min before surgery; in the I/R + DFO group, DFO 100 mg/kg was injected intraperitoneally 1 h before operation and 12 h after operation. Blood samples were taken from the inferior hepatic vena cava 24 h after reperfusion. After anesthesia, the rats were killed and part of their liver tissue was removed. The pathological changes of liver tissue sections were observed under a high-power microscope, and the liver injury was evaluated. Serum malondialdehyde (MDA) and serum levels of ALT, AST and IL-6 were determined by the ELISA method, Reduced glutathione (GSH), glutathione peroxidase 4 (GPX4), MDA, Fe2 + and superoxide dismutase (SOD) were determined in the liver tissue. Compared with the sham group, the serum levels of the IL-6,MDA, AST and ALT in I/R group were obviously higher (P < 0.05); The levels of MDA and Fe²⁺ in liver tissue were significantly increased (P < 0.05).The levels of SOD, GSH and GPX4 in liver tissue were decreased. The levels of serum MDA, IL-6, AST, and ALT in the I/R + Fer-1 and I/R + DFO groups were significantly lower than those in the I/R group at 24 h after reperfusion. In the I/R + Fer-1 group, the level of MDA in liver tissue decreased significantly, while the level of SOD, GSH and GPX4 in intestinal tissue increased (P < 0.05). In The I/R + DFO group, the levels of MDA and Fe²⁺ in liver tissue decreased significantly, while the level of SOD in intestinal tissue increased (P < 0.05). Ferroptosis is involved in pathophysiological process of liver injury after cold ischemia-reperfusion in AOLT rats.

Three-dimensional bioprinting is getting enormous attention among the scientific community for its application in complex regenerative tissue engineering applications. One of the focus areas of 3-D bioprinting is Skin tissue engineering. Skin is the largest external organ and also the outer protective layer is prone to injuries due to accidents, burns, pathologic diseases like diabetes, and immobilization of patients due to other health conditions, etc. The demand for skin tissue and the need for an off-the-shelf skin construct to treat patients is increasing on an alarming basis. Conventional approaches like skin grafting increase morbidity. Other approaches include acellular grafts, where integration with the host tissue is a major concern. The emerging technology of the future is 3D bioprinting, where different biopolymers or hybrid polymers together provide the properties of extracellular matrix (ECM) and tissue microenvironment needed for cellular growth and proliferation. This raises the hope for the possibility of a shelf skin construct, which can be used on demand or even skin can be printed directly on the wound site (in-situ printing) based on the depth and complex structure of the wound site. In the present review article, we have tried to provide an overview of Skin tissue engineering, Conventional advancement in technology, 3D bioprinting and bioprinters for skin 3D printing, different biomaterials for skin 3D bioprinting applications, desirable properties of biomaterials and future challenges.

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.

Left ventricular assist devices (LVADs) are implanted in patients with heart failure to support cardiac circulation. However, no standardized methods have been established for LVAD driveline exit site management for the prevention of infections. Therefore, this study evaluated the efficacy of modified driveline management compared with that of conventional driveline management. We retrospectively assessed the outcomes of 262 patients who underwent continuous-flow LVAD implantation between January 2005 and March 2023 at Osaka University in Japan. In conventional driveline management, an LVAD driveline penetrates the skin along the body surface and is fixed near the penetration site (n = 224). In contrast, in our modified fixation method, the LVAD driveline vertically penetrates the skin to prevent ischemia at the driveline exit site and is fixed at a distant abdominal site to prevent the movement of the driveline exit site due to body movement (n = 38). The rates of freedom from LVAD driveline infection in patients with conventional driveline management were 86, 75, and 63% at 1, 2, and 3 years after LVAD implantation, respectively. The rate of freedom from LVAD driveline infection in patients managed by the modified fixation method was 91% at 1, 2, as well as 3 years after LVAD implantation. The freedom rates from LVAD driveline infection in the patients with modified fixation method was lower than in the patients with the conventional method (p = 0.04). Our study revealed that the modified fixation method may offer the possibility for preventing LVAD driveline infection.

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.