International Journal of Artificial Organs最新文献

Introduction: We aimed to investigate the impact of preoperative Arterial Stiffness Index (ASI) values on primary graft patency following peripheral arterial bypass surgery.

Methods: This retrospective cohort study included 92 patients who underwent femoro-popliteal bypass surgery between January 2019 and November 2024. Preoperative ASI values were measured using the Vasolab 5000 device. Patients were divided into two groups based on an ASI cut-off value of 10.0. Primary graft patency rates, Kaplan-Meier survival analysis, and multivariate Cox regression were performed to assess the relationship between ASI and graft outcomes.

Results: Patients with ASI >10.0 exhibited significantly lower 12-month primary graft patency rates compared to those with ASI ⩽10.0 (61.9% vs 88.0%, p = 0.008). Multivariate Cox regression analysis identified high ASI as an independent predictor of graft failure (HR: 2.15; 95% CI: 1.15-4.03; p = 0.016), along with diabetes mellitus and the use of synthetic graft material.

Conclusion: Preoperative ASI values are independently associated with primary graft patency after peripheral arterial bypass surgery. Arterial stiffness assessment may serve as a useful non-invasive tool for risk stratification in vascular surgery candidates.

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.

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.

This case describes an 82-year-old male patient presenting with persistent upper abdominal colic, diagnosed as severe acute pancreatitis. The patient then suffered a cytokine storm, as well as renal dysfunction. Therefore, the patient underwent two sessions of coupled plasma filtration adsorption (CPFA) therapy utilising the CA330 cytokine adsorption cartridge as the adsorbent. The first CPFA session lasted 8 h, followed by a 4-h interval (during which continuous veno-venous haemodialysis therapy was provided), and the second 8-h CPFA session started. Due to family requests and comprehensive consideration by the medical team, the second CPFA session was extended to 20 h. Ultimately, the patient was weaned off blood purification therapy (43 h after its initiation). The study demonstrated a significant reduction in cytokine levels as the course of treatment increased. However, beyond a specific threshold, cytokine adsorption may reach saturation. The medicinal applications of CPFA (particularly CA330) deserve more investigation.

Perforation on tympanic membrane could decrease the hearing ability. In some cases, myringoplasty should be performed. Myringoplasty requires material as patch to cover tympanic membrane's hole. This study is aimed to create innovation based on chitosan-collagen with glycerol plasticizers as scaffold patch for tympanic membrane perforation. The sample preparation method included mixing various concentrations of chitosan-collagen with the ratio of 1:0; 9:1; 8:2; 7:3 and 0.5 ml of glycerol for each sample variation. The characterization included FTIR test, morphological test, sound transmission class test, tensile strength test, degradation test, swelling test, and antibacterial test. The functional group test showed that in the sample variations 9:1; 8:2; 7:3 there was an absorption at the wave number 2347 cm^-1 which showed deformation of the NH group. Morphological analysis showed that as the collagen concentration increased, the microstructure exhibited more pronounced fine wrinkles. The sound transmission class test showed all sample variations did not reduce the sound so the scaffold patch transmitted sound properly. Tensile strength test showed the sample with the variation of 8:2 had the greatest strength value (8.02 MPa) but still below the value of tympanic membrane tensile strength ±20 MPa. The degradation test showed the samples were able to survive during the tympanic membrane healing process for approximately one until 2 months. The optimization of plasticizer amount need to be adjusted in order to increase tensile strength. The presence of free hydrophilic groups (group COOH, NH2, and -OH) cause the sample to have hydrophilic properties so that it is easily degraded and undergoes swelling. In antibacterial assay, the inhibition zone was not formed because chitosan could not diffuse through the agar.

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.