International Journal of Artificial Organs最新文献

In vitro hemolysis, assessed through the normalized hemolysis index (NIH) and the modified hemolysis index (MIH), serves as a critical indicator of the hemocompatibility of rotary blood pump designs. Despite the widespread application of the American Society for Testing and Materials (ASTM) standards in conducting in vitro hemolysis testing, the NIH and MIH values for a specific pump can vary considerably across different research centers or even between individual tests. To reduce this variability and facilitate global comparisons of hemolysis levels, this article reviews the underlying theory, existing literature, and empirical knowledge, alongside the practices implemented at the authors' facility. The reviewed factors influencing the variability of the hemolysis index encompass the selection of blood donor species, the source and method of blood withdrawal, blood handling and regulation, the choice of anticoagulants, the configuration of the circulation loop, local flow conditions within the loop, and the measurement of plasma-free hemoglobin. Detailed justifications and recommendations for each factor within a standardized testing framework are provided. The three primary factors that may yield more reliable and universally comparable results include enhancing clinical relevance, minimizing additional blood damage, and preventing blood clot formation. By regulating the associated parameters, it is possible to minimize measurement variance even in the absence of a predictive device.

Objective: This study aimed to investigate the relationship between the changes of serum indoxyl sulfate (IS) concentration, Klotho protein level, and cardiovascular complications in patients with chronic kidney disease (CKD) stage 3-5.

Methods: A total of 108 patients with CKD stage 3-5 were selected. They were divided into three groups: CKD stage 3-4 group, CKD stage 5 non-dialysis group, and CKD stage 5 dialysis group. Echocardiography was used to measure left ventricular diameter (LVD), interventricular septal thickness (IVS), left ventricular posterior wall thickness (LVPW), and calcification.

Results: there was no significant difference in age between the healthy control group and the patients with CKD stage 3-5 (p > 0.05). Compared to healthy controls, serum creatinine, serum phosphorus, iPTH, serum IS, left ventricular diameter, interventricular septum thickness, left ventricular septal wall thickness, and the proportion of valve calcification increased gradually, while serum calcium and Klotho protein decreased The level of serum IS was positively correlated with the level of LVD, IVS, and valve calcification in CKD patients, while the level of serum Klotho protein was negatively correlated with the level of IVS and valve calcification in CKD patients.

Conclusion: In patients with chronic kidney disease (CKD), the incidence of cardiovascular complications is significantly higher than in the general population. The increase of serum IS level and the decrease of serum Klotho protein level are closely related to cardiac injury, it IS suggested that serum IS level and Klotho protein level may be a good index for monitoring cardiovascular injury in CKD patients.

Background: There has been an exponential increase in the utilization of temporary mechanical support devices for bridging Status 2 heart transplant candidates. The aim of our study is to determine outcomes in dual organ heart/kidney recipients for patients bridged with an Impella 5.5 versus IABP.

Methods: We evaluated the UNOS database and analyzed Status 2 patients who underwent dual organ heart/kidney transplantation after being bridged with an Impella 5.5 or IABP from October 2019 (time of Impella 5.5 FDA approval) until March 2024.

Results: A total of 457 patients who underwent Heart/Kidney transplant (HKT) were identified, of which 73% (334/457) were bridged with an IABP and 27% (123/457) with an Impella 5.5. Within the IABP cohort, 37% (122/334) were on dialysis pre-transplant compared to 43% (53/123) in the Impella group (p = 0.409). Patients in the Impella group had worse functional status, liver function, and filling pressures. There was no difference in the need for dialysis post-transplant (32% vs 29%, p = 0.613). Survival at 30, 180, and 360 days and the rates of primary graft dysfunction, acute, and chronic rejection were similar between the two groups.

Conclusion: Both IABP and Impella appear to be safe for bridging dual organ heart and kidney transplant candidates, with comparable post-transplant heart and kidney graft function, complications, and survival up to 2 years. Patients receiving Impella 5.5 appear to be sicker and as a result, this percutaneous temporary mechanical circulatory support device may confer some advantages, especially for patients with dual organ failure who undergo transplantation.

Flatfoot is a very common condition that alters gait mechanics and is usually accompanied by pain. In this current study, two types of custom-made insoles using polyethylene and silicon, respectively, were designed to help alleviate this condition. Such insoles are tested for their functionality using advanced 3D printing and finite element analysis. Tests were conducted at body weights of 60, 80, 100, and 120 kg. Results indicated that silicone insoles outperformed the others by effecting a better redistribution of pressure with higher magnitudes of strain and stress. Specifically, silicon had strain values between 1.44 × 10^-7 and 2.88 × 10^-7, much lower than polyethylene's 5.92 × 10^-5-1.18 × 10^-4. Whereby, silicon would withstand stress levels to about 47,058 Pa, while polyethylene would do so at 31,932 Pa, making it more resilient under higher loads. Further validation through kinematic analysis proved that silicon insoles enhance the symmetry of walk and disperses the concentration of pressures of the feet, therefore providing more comfort and support during locomotion. These results suggest that silicon insoles offer significant benefits for managing flatfoot, paving the way for future innovations in personalized orthopedic footwear.

Background: The concentration of bicarbonate in dialysis fluid (Dbic) that regulates acid-base balance in dialyzed patients is individually adjusted and may be modified during a hemodialysis session. We evaluated the impact of modifications of Dbic on plasma electrolytes.

Methods: Two midweek hemodialysis sessions were monitored in 25 anuric, prevalent hemodialysis patients (67.9 ± 9.3 years old, 32% females). During the first session (treatment A) Dbic was constant at 33.6 ± 1.7 mmol/L, while for the second week (treatment B) it was on average 30.8 ± 2.3 mmol/L for the initial 2 h and 34.0 ± 2.5 mmol/L for the last 2 h.

Results: During treatments A and B plasma bicarbonate (Pbic) increased during the sessions and was lower for treatment B than A at 60 and 120 min of dialysis. Plasma chloride decreased during treatments A and B and was significantly higher at 60 and 120 min of dialysis in treatment B than in treatment A. An increase of plasma calcium was observed during both treatments and it was higher for treatment B than A at 60 and 120 min. A similar profile of plasma sodium and potassium was observed during treatments A and B. The difference in Pbic correlated positively, whereas the differences in plasma chloride and calcium correlated negatively, with the difference in Dbic between treatments B and A.

Conclusion: Modifications of dialysate bicarbonate may influence the concentrations of some other electrolytes in plasma; for each percent of Dbic increase one may expect -0.27 and -0.16% change in plasma chloride and calcium, respectively.

Introduction: Hemodialysis (HD) represents a necessary medical intervention for patients with end stage kidney disease (ESKD) with a high carbon footprint that significantly consumes natural resources (i.e. water). Reduction of dialysate flow rate is one strategy that directly targets water waste during HD.

Methods: A retrospective multicenter, observational study was conducted over 12 months in patients with AKI-D and ESKD to evaluate treatments with mid-range dialysate flow rates set at Qd 300 mL/min (Green HD) using the Tablo^® HD System (Outset Medical) versus flow rates ⩾Qd 500 mL/min (Conventional systems).

Results: One thousand one hundred ninety-five treatments were performed in 433 patients using Green HD (Qd = 300 mL/min, n = 575) and Conventional systems (Qd ⩾500 mL/min, n = 620). Mean Qd for Green HD was 300.0 ± 0.0 and mean Qd for the Conventional systems was 686.6 ± 88.3 mL/min. Mean blood flow rates were significantly lower among patients treated with Green HD. Reductions in TACurea and post dialysis serum potassium were similar between the two groups. Estimates for resource utilization were lower using Green HD compared to Conventional systems.

Conclusion: These findings support that higher dialysate flow rates using Conventional systems yield minimal if any benefit in small solute clearance compared to mid-range flow rates. Green HD using the Tablo^® HD System results in comparable benefits in ESKD patients with significant conservation of water resources.

Background: Quality of life (QoL) serves as a critical metric for evaluating the well-being of individuals undergoing hemodialysis. This study sought to identify the factors that impact QoL in hemodialysis patients using the Kidney Disease Quality of Life-36 (KDQOL-36) questionnaire.

Methods: A cross-sectional study was conducted with 74 hemodialysis patients at our institution between August 2021 and August 2024. Participants completed the KDQOL-36, Hamilton Depression Scale (HAMD-24), and Social Support Rating Scale (SSRS). Demographic and clinical variables were collected. Statistical methods, including descriptive analysis, correlation testing, and multiple regression, were used to determine factors linked to KDQOL-36 outcomes.

Results: The average age of participants was 57.59 ± 13.61 years, with a median dialysis duration of 36.0 (12.0-76.5) months. The subscale scores on the KDQOL-36 were as follows: Symptoms/Problems List (S): median 78.1 (IQR = 65.6-87.5), Effects of Kidney Disease (E): median 59.4 (IQR = 43.8-71.9), Burden of Kidney Disease (B): median 43.8 (IQR = 31.3-62.5), SF-12 Physical Component Summary (PCS): mean 41.35 ± 8.49, and SF-12 Mental Component Summary (MCS): mean 46.73 ± 11.66. Regression analysis identified age, dialysis duration, hemoglobin levels, depression severity, and social support as key predictors of QoL across the KDQOL-36 subscales.

Conclusion: Several factors contribute to the QoL of hemodialysis patients. Interventions addressing modifiable factors such as anemia, depression, and social support enhancement could potentially improve the overall QoL for this patient group.

Microbubbles (MBs) of air occur in the hemodialysis (HD) extracorporeal circuit and may enter the bloodlines of the patient. The aim of the present study was to investigate possible sites of contamination. Seventeen patients performed 20 HD (Baxter AK200S n = 5 and Artis n = 15) and 930 ultrasound measurements of MBs/min (Hatteland CMD10 device). Detection ranges were diameters between 2.5 and 50 µm. Hemodiafiltration with postdilution (HDF-post) was performed in 14 dialyses, predilution (HDF-pre) in 1 dialysis, and HD using hemocontrol (HDhc) in 5 dialyses. Measurement points were M1-after the blood access, M2-before the dialyzer, M3-after the dialyzer, and M4-after the venous chamber. At each point, 10 measures of MBs were performed. MB contamination of the blood was larger at all points when the access was an arteriovenous fistula compared to a central dialysis catheter (p < 0.001). MB levels with the AK200 versus the Artis were lower at M1, higher at M2 (p ⩽ 0.005), and were similar at M3 and M4. HDF-pre had fewer MBs than HDF-post, whereas HDhc had more MBs than HDF-post (p < 0.001). An increase of MBs was seen at M2 during an internal "Autotest." No air alarms were induced during dialyses. MBs were detected in the extra corporeal circuit at all points investigated. The venous chambers used did not significantly reduce contamination. The detected MBs did not induce air alarms when the blood returned to the patient.

There is a growing recognition of the significance of the mental and emotional readiness of patients prior to undergoing heart surgery. Self Determination Theory, a part of Positive Psychology delves into the realms of happiness, drive, and satisfaction in life. This theory highlights the importance of autonomy, competence, and relatedness as fundamental basic psychological needs necessary for attaining life satisfaction, motivation, and psychological well-being. To examine these aspects in this study, it is assessed the levels of basic psychological needs, motivation levels, and levels of psychological energy of patients undergoing heart surgery. Basic Psychological Needs Scale, Motivation Scale, and Psychological Energy Scale are used for data collection. Through an analysis involving independent samples t-tests on 55 patients, the research findings revealed these psychological outcomes associated with heart surgery. Following heart surgery, participants showed decreases in their levels of psychological needs satisfaction, motivation, and psychological energy.

We evaluated the viability of Vero and the osteogenic differentiation potential of mesenchymal stem cells (MSCs) cells cultured on alpha-TCP-RL, SiTCP-RL, and SiTCP-RC bioceramic scaffolds. Viability of Vero cells and MSCs were evaluated by the MTT assay. The morphological pattern of the two cell types was analyzed by SEM. The functional activity of MSCs was evaluated by a cytochemical assay and osteogenic differentiation by Alizarin red staining and ALP activity. In the MTT assay, Vero cells showed high activity in the extract cytotoxicity test but low activity in the direct contact test. SEM morphological analysis showed the spread of cells with irregular and flattened morphology on the different substrates. We found a smaller number of MSCs than Vero cells on the ceramics. The cytochemical analysis revealed MSCs indicating high functional activity. We observed signs of osteogenic differentiation of MSCs by quantification of ALP activity and formation of mineralized organic matrix.