International Journal of Artificial Organs最新文献

Peritoneal dialysis (PD) is a life-sustaining treatment for end-stage kidney disease but contributes significantly to environmental degradation due to its reliance on single-use plastics, energy-intensive manufacturing and high-volume transport. Redesigning PD products for sustainability is increasingly important as healthcare systems seek to reduce their carbon footprint. In this study, ten high-use peritoneal dialysis (PD) products were redesigned using life cycle thinking. Interventions included low-carbon transport (electric vans), renewable energy and improved waste treatment (pyrolysis). Life cycle inventories (LCIs) were modelled in Open Life Cycle Assessment (OpenLCA)and modelled using cradle-to-gate carbon footprints (kg CO₂-eq) to compare redesigned and conventional versions. All redesigned products achieved carbon footprint reductions, with eight showing decreases greater than 40%. The automated PD set and 2 L dialysate bag saw reductions of 63% and 54%, respectively (saving 1.15 and 0.86 kg CO2-eq per item). The APD machine achieved the largest percentage reduction at 87%, primarily driven by the elimination of printed packaging and the use of renewable electricity. Key contributors to emissions savings across products included lower-impact transport, sustainable packaging materials and circular waste strategies. Redesigning PD products using sustainable materials and processes can deliver substantial environmental benefits without compromising functionality. These findings support evidence-based pathways for reducing emissions in kidney care through product innovation and procurement reform.

Cholic acid (CA) and indoxyl sulfate (IS) are toxins associated with biliary and renal disease. Protein binding prevents removal by traditional dialysis. Dissolving binding molecules such as albumin in dialysate enables detoxification. We created a benchtop albumin dialysis test platform. We used it to validate a mathematical model of CA/IS removal. Toxin-containing blood analog solution was dialyzed using two dialyzers at five flow rates against albumin dialysate. One condition was used to estimate toxin binding affinity to albumin and the free toxin transmembrane transfer coefficient (K_freeA). Other conditions validated modeling results and revealed the impact of dialysate flow rate and dialyzer properties on detoxification (measured by mass spectrometry). We accurately predicted CA/IS removal. The normalized root mean squared error never exceeds 11.5% of the starting amount. Increasing dialysate side flow rate up to 150 mL/min improved toxin removal. Further increases produced no benefit. K_freeA was independent of flow rate. Our data fits a result from the newly developed AMOR system, in which total bile acids declined with treatment. This model and benchtop setup aim to predict clinical CA/IS clearance and optimize device design for clinical trials. This will mean fewer unsuccessful trials and enable testing of new dialysate formulations.

Background: This study aimed to evaluate the impact of sarcopenia and frailty on the quality of life of older hemodialysis patients.

Methods: Seventy hemodialysis patients aged ⩾60 years were assessed. Daily living activities (Katz Index), depression (Yesavage Scale), frailty (Fried's Criteria), and sarcopenia (EWGSOP2) were evaluated. Quality of life was measured using the KDQOL-36 questionnaire.

Results: The median age was 67 years, and 50% were female. Nineteen patients (27.1%) were partially dependent, 71.4% were pre-frail, and 15.7% were frail. Probable sarcopenia was detected in 77.1%, and sarcopenia in 8.6% of patients. Sarcopenia was associated with older age, higher dependency, depression, lower income, and frailty (p < 0.05). It was also related to the KDQOL-36 physical component (p = 0.031), while frailty correlated with the symptom component (p = 0.047).

Conclusion: Frailty and sarcopenia are common in older hemodialysis patients and adversely affect their quality of life.

Aim: This study aimed to assess the relationship between arteriovenous fistula (AVF) functional status and quality of life and to identify influencing factors.

Method: Data for this cross-sectional study were collected from 221 chronic hemodialysis patients between May and September 2024.

Results: AVF functional status was significantly lower in male patients who had undergone four or more AVF operations, had an AVF at the elbow site, or had two to three temporary catheter insertions. There was a moderate negative correlation between the SF-12 Physical Composite and age and a positive correlation between Kt/V. There was a moderate negative correlation between the SF-12 Physical Composite and AVF-AS. The regression analysis revealed that the blood pump speed, Kt/V, and the SF-12 Physical Composite significantly affected the AVF-AS scores, explaining 21.5% of the total variance.

Conclusion: In our study, we founded that a well-functioning AVF provided adequate dialysis, improving the patients' physical quality of life.

Blood-handling devices are commonly used for blood transportation or regulation, but their specialized flow channel geometries tend to create high-shear-stress flow regimes, which may induce excessive cellular damage risks and energy dissipation. To address this, this study combines computational fluid dynamics and particle image velocimetry experimental methods to establish nozzle reference models with multiple orifice diameter configurations. Based on entropy generation theory and Ω vortex identification methods, the underlying energy dissipation mechanisms and vortex dynamics under distinct high-shear-stress conditions are analyzed. The results indicate that shear flow intensity is highly correlated with energy dissipation due to entropy production. Attenuating turbulence in the flow field simultaneously suppresses shear stress damage and energy loss, while lowering shear flow intensity promotes the decomposition of vortices downstream, broadening their spatial distribution. High flow velocity alone does not directly induce shear stress or entropy-related energy dissipation; rather, an excessively steep velocity gradient is the primary factor affecting flow field safety and efficiency. A 94% rise in velocity gradient results in average increases of 97.6% in shear stress and 99.6% in energy entropy production. During flow regime transition or under pronounced velocity gradients, shear-dominated vortices readily form and generate vortex-like energy dissipation during evolution, which is a key factor exacerbating energy loss in high-shear-stress flow fields. This study elucidates the energy dissipation mechanisms and vortex dynamics in high-shear-stress flow fields of blood-handling devices, providing theoretical and technical support for optimizing flow fields and performance in relevant devices.

Aim: Patients with ESRD who receive dialysis experience a wide range of unpleasant symptoms that have a negative effect on patient prognosis. The aim of this study was to evaluate the relationship between dialysis symptoms, adherence to interdialytic weight gain, fluid control, and associated factors in hemodialysis patients.

Methods: This study was conducted in a descriptive and cross-sectional design. Demographic and clinical characteristics form, mean of interdialytic weight gain last 12 hemodialysis sessions, Fluid Control in Hemodialysis Patients Scale, and Dialysis Symptom Index (DSI) were used to collect data.

Results: Patients with chronic illnesses and unemployment patients experienced higher DSI scores. The literate participants had a significantly higher DSI and lower adequacy of fluid intake. The regression analysis results showed that employment, chronic diseases, dialysis adequacy, and compliance with fluid intake explained 20.3% of the variance and that the model was a significant predictor of the DSI.

Conclusion: Dialysis symptoms were seen prevalently among the patients, and factors such as employment status, chronic disease, dialysis adequacy, and fluid intake compliance affected the DSI. It is important to monitor the fluid volume status and hemodialysis symptoms of hemodialysis patients regularly.

Background: Refractory septic shock (RSS) in children carries high mortality despite advances in critical care. Extracorporeal membrane oxygenation (ECMO) is a rescue therapy when conventional management fails. Evidence from Latin America remains limited, with no detailed reports from Chile.

Methods: We conducted a retrospective single-center study (2009-2024) in a Chilean Pediatric ICU. Patients aged 1 month to 17 years with septic shock unresponsive to maximal conventional therapy were included. We analyzed demographics, illness severity, ECMO modality, complications, and outcomes. Primary endpoint was survival to hospital discharge.

Results: Nine patients received ECMO (median age = 6.3 years). All had RSS, frequently associated with severe ARDS. Configurations included venoarterial (VA; n = 4), venovenous (VV; n = 4), and venoarteriovenous (VAV; n = 1), all via peripheral cannulation. Pre-ECMO median vasoactive-inotropic score was 117, and 78% required renal replacement therapy during ECMO. Overall survival was 55% (5/9). Survivors had longer ECMO runs (median 11 days vs 3 days) and ICU stays (median 63 days vs 5 days). Hemorrhage was the most frequent complication (intracranial n = 3; gastrointestinal n = 1). One survivor developed hemiparesis; no cognitive impairment was observed at 1-year follow-up.

Conclusions: ECMO can be an effective rescue therapy for pediatric RSS, even without central cannulation capability. Distinguishing cardiogenic from vasoplegic phenotypes and identifying severe ARDS guided configuration selection (VA vs VV). These findings highlight the feasibility of peripheral ECMO in carefully selected patients within resource-limited settings, achieving survival comparable to international reports.

Background: Achieving adequate sedation on extracorporeal membrane oxygenation (ECMO) is challenging due to altered pharmacokinetics. Limited data exists on phenobarbital in adult ECMO patients. The aim was to characterize the volume of distribution (Vd) and dosing.

Methods: This single-center retrospective study examined adult ECMO patients who received intravenous phenobarbital and corresponding serum concentrations between January 1, 2017 and March 1, 2024. Phenobarbital levels for analysis were obtained 0.5-4 h after phenobarbital loading dose (LD) and up to 4 h prior to a maintenance dose; this time frame was adjusted to 0.5-1 h if on continuous venovenous hemofiltration (CVVH).

Results: Sixteen venovenous ECMO patients with 18 LD and 70 phenobarbital concentrations were evaluated. The median LD was 1225 mg (796.3-1437.8); 15 mg/kg (8.8-16.2) total body weight (TBW). The median total Vd was 67.7 L (46.8-80.8), 0.94 L/kg (0.72-1.22) ideal body weight (IBW), and 0.71 L/kg (0.67-0.82) TBW. Weight-based LD and concentration demonstrated a stronger correlation for TBW (r = 0.93, p < 0.001) versus IBW (r = 0.64, p = 0.003). Comparing BMI <30 and BMI ⩾30 kg/m² patients there was a difference in total Vd (p = 0.02) and IBW-normalized Vd (p = 0.006), but no difference in TBW-normalized Vd (p = 0.31). The median maintenance dose was 2.4 mg/kg/day (1.7-2.7) TBW; CVVH patients required 11.7 mg/kg/day TBW. Phenobarbital concentration change was <3% after ECMO decannulation.

Conclusion: In adult ECMO patients, phenobarbital's Vd normalized to TBW, was consistent with critically ill non-ECMO patients. Obesity affected Vd, CVVH influenced maintenance dosing, but ECMO decannulation did not impact phenobarbital concentrations.

Background: Decannulation from veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is frequently associated with the clinical onset of systemic inflammatory response syndrome (SIRS). However, the cytokine profile underlying this response remains unclear. This study aimed to determine whether pro-inflammatory cytokine levels change in patients with SIRS following VA-ECMO decannulation.

Methods: We conducted a prospective observational pre-post study at a single tertiary academic center. Thirty consecutive adult patients who developed clinical SIRS within 24 h of successful VA-ECMO decannulation were included. Plasma concentrations of interleukin (IL)-1α, IL-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) were measured at four time points: 1 h before, and 1, 12, and 24 h after decannulation. Repeated measures analysis of variance (ANOVA) was used to evaluate temporal changes in cytokine levels.

Results: Of 110 screened VA-ECMO patients, 30 (27.3%) met the inclusion criteria. The mean age was 48.8 ± 10.9 years. Baseline cytokine levels prior to decannulation were as follows: IL-1α 6.68 ± 10.99 pg/mL, IL-1β 0.28 ± 0.21 pg/mL, IL-6 18.21 ± 55.76 pg/mL, and TNF-α 5.62 ± 5.89 pg/mL. No significant changes were observed in IL-1α, IL-1β, or IL-6 levels across all time points. TNF-α showed a statistically significant decline at 24 h post-decannulation (4.15 ± 4.65 pg/mL) compared to baseline (p = 0.044).

Conclusions: In patients developing SIRS following VA-ECMO decannulation, plasma levels of key pro-inflammatory cytokines remained largely unchanged over a 24-h period. These findings suggest that the clinical manifestations of SIRS in this context may not be directly driven by traditional pro-inflammatory cytokine surges, warranting further investigation into alternative inflammatory mediators or mechanisms.Registered in clinical trials registry:NCT04678518, MRC-01-20-155.

Rotary blood pumps (RBPs), used as Ventricular assist devices (VADs), feature a suspended impeller (rotor) within a housing (stator). Titanium alloys are mostly used for those parts, but their limited wear resistance in critical contact areas, leading to scratches and promoting thrombus formation. Therefore, hard material coatings (HMCs) can be applied to increase wear resistance and bonding agents ensure stable coatings on the bulk material. Still, coating damage may occur and expose the material to blood, requiring hemocompatibility assessment. Therefore, their hemocompatibility must be evaluated as well as that of the HMCs. Platelet adhesion as thrombus formation indicator was investigated using an in vitro flow chamber and fluorescence microscopy for the following materials: Silicon diamond-like carbon (SiDLC), titanium nitride with and without droplets (TiN_D, TiN), bonding agents chrome (Cr), chrome nitride (CrN), uncoated Ti6Al4V (Ti), and aluminum (Alu) as positive control. CFD simulations determined wall shear rates, averaging 5730.5 1/s on the evaluated area. The normalized percentage of the covered surface (NCSA) area was statistically evaluated (p-values, Wilcoxon effect size). NCSA analysis showed that Alu had the highest value (8.7), significantly exceeding CrN and SiDLC (both 0.3, p < 0.05). Cr (3.6) exhibited significantly more platelets than CrN with a medium effect compared to CrN, Ti (0.2), TiN (0.3), and SiDLC, and a weak effect compared to TiN_D (0.4) and Alu. No significant differences were observed among HMCs, Ti, and CrN. This study highlights Cr's elevated thrombogenicity, whereas the other surfaces (except Alu) showed hemocompatibility comparable to Ti, supporting their use in VADs.