Search Results (64)

Blood collection tubes are widely used medical devices. Inaccurate citrate anticoagulant concentration can influence the results of coagulation tests. The producer’s expertise and responsibility are considered the quality safeguards. However, the tubes undergo changes during their lifecycle, partly due to storage conditions, and the end user or a third party has no comprehensive insight. A methodology is necessary to reveal the tube’s inherent characteristics. We provide insight into the anionic–cationic composition and pH of anticoagulant solutions in commercial tubes using high-performance ion exchange chromatography on a purified water model, making the anticoagulant volume accuracy assessment possible through a direct dye-dilution method. The results revealed differences between the tubes of two producers, Greiner BIO-ONE (A and A(nr)) and BD (C). Tube C has the most accurate anticoagulant amount. Both brands contain buffered citrate. The method of buffer preparation is not a source of interferant for the spectrometric method of the tubes’ quality evaluation. Acetate, formate, chloride, nitrite, sulfate, oxalate, bromide, and nitrate impurities were determined in anticoagulant solutions, all in tube A and some in the others. Tubes C exhibit the highest contamination with cations. Full article

Background: Regional citrate anticoagulation (RCA) is the recommended first-line strategy for continuous renal replacement therapy (CRRT), yet global implementation remains inconsistent. We reviewed our extensive single-center experience to provide a real-life evaluation of RCA feasibility, limitations, and environmental sustainability. Methods: We retrospectively analyzed RCA treatments performed in our center from 2012 to 2022. Technical performance was assessed by circuit patency and failure timing. Environmental impact was evaluated by simulating filter consumption and hazardous waste production compared to a projected strategy using unfractionated heparin (UFH). Results: RCA utilization grew progressively, reaching 98% of all treatments. The technique showed an 80.2% success rate and a robust safety profile, demonstrating excellent feasibility and efficacy in clinical practice. However, among circuits intended for 72 h survival, over one-third failed prematurely; segmented regression confirmed a critical high-risk period within the first 24 h, with a significantly higher rate of circuit loss compared to the subsequent period (p < 0.05). In our simulation, RCA adoption saved over 1000 filters, preventing the emission of approximately 12 tons of CO₂ equivalent. Conclusions: RCA is a safe, effective, and environmentally appealing method of CRRT. However, significant room for improvement remains; refining the technique to increase circuit success rates is essential to optimize clinical efficiency and further minimize the ecological footprint of acute renal care. Full article

Hemostasis depends on the coordinated interaction between platelets, coagulation factors, endothelium, and shear forces. Current point-of-care (POC) assays evaluate isolated components of haemostasis or operate under nearly static conditions, limiting their ability to reproduce physiological thrombus formation. In this study, we performed the technical validation of Smart Clot, a fully automated, microfluidic POC platform that quantifies platelet aggregation, fibrin formation, and total thrombus growth under controlled arterial shear using unmodified whole blood. Recalcified citrated blood was perfused over collagen at $\dot{\gamma }$_w = 300 s⁻¹. Dual-channel epifluorescence microscopy acquired platelet and fibrin(ogen) signals at 1 frame per second. Integrated Density time-series were fitted with a five-parameter logistic model; first derivatives and their integrals yielded standardized pseudo-volumes for platelets, fibrin(ogen), and total thrombus. Sixty-two healthy donors established reference distributions; one-hundred-thirteen patients on antithrombotic therapy assessed pharmacodynamic sensitivity. Platelet-derived parameters were approximately normally distributed, whereas fibrin(ogen) and total thrombus values followed log-normal patterns. Anticoagulants and antiplatelet agents produced graded, mechanism-consistent inhibition of all thrombus components. Cardiopulmonary bypass samples showed profound but transient suppression of platelet and fibrin activity. Across activity ranges, multiple statistical assessments supported high analytical repeatability. Smart Clot provides rapid, reproducible, flow-aware quantification of platelet–fibrin dynamics, capturing pharmacological modulation and peri-operative impairment with high sensitivity. These results support its potential as a next-generation POC assay for physiological hemostasis assessment. Full article

Background: The accurate detection of remifentanil and sufentanil in biological samples is challenged by their rapid metabolism and instability, complicating clinical and forensic toxicology analysis. This study aimed to evaluate the stability of remifentanil, sufentanil, and their primary metabolites—remifentanil acid and norsufentanil—in human whole blood and urine. Methods: A high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) method was developed and validated for simultaneous quantification, demonstrating satisfactory linearity (0.10–200 ng/mL, r² > 0.99), detection limits (0.01–0.20 ng/mL), and recovery rates (85.06–119.42%). Stability was assessed under varying temperatures (4 °C, −20 °C, −80 °C) and anticoagulant conditions (EDTA-K₂, sodium heparin, sodium citrate) over 35 days. Results: Remifentanil exhibited significant instability in whole blood, degrading over 50% within 6 h at 4 °C, whereas stability was markedly improved at −80 °C and in sodium citrate-containing samples. Remifentanil acid remained stable for up to 35 days at −80 °C. Sufentanil was generally more stable, particularly at −80 °C in both blood and urine, while norsufentanil remained stable for 7 days at −20 °C in citrate-anticoagulated blood but degraded rapidly at 4 °C. These findings support specific recommendations for sample preservation, including storage at −80 °C and the use of sodium citrate as an anticoagulant, to enhance detection reliability in toxicological and pharmacokinetic studies. Full article

Critically ill patients receiving continuous renal replacement therapy (CRRT) face distinct nutritional challenges requiring specialized parenteral nutrition (PN) strategies. This review synthesizes current evidence with clinical expertise to provide a comprehensive nutritional framework for this population. Key findings reveal that CRRT significantly impacts nutrient homeostasis through daily losses of amino acids (14–22 g), water-soluble vitamins, and trace elements via the extracorporeal circuit. Results from observational studies demonstrate that higher protein targets (1.8–2.5 g/kg/day) are necessary to achieve positive nitrogen balance, while energy prescriptions must subtract “hidden” calories from citrate anticoagulation (3–4 kcal/mmol) and propofol (1.1 kcal/mL). Clinical outcome data, though primarily observational, indicate that achieving nutritional adequacy correlates with reduced ICU stays (average reduction 2.1–3.4 days), shorter mechanical ventilation duration, and improved functional recovery. Evidence supports that early PN prescription when indicated, coupled with systematic consideration of therapy modality, extracorporeal losses, oral intake capacity, and mobilization status, optimizes nutritional support. We conclude that successful implementation requires: (1) dynamic adjustment based on CRRT parameters, (2) integration with enteral nutrition when feasible, (3) regular metabolic monitoring, (4) multidisciplinary collaboration, and (5) structured protocols. Future research using point-of-care analysis and AI-driven support systems is needed to establish evidence-based guidelines in this specialized population. Full article

Introduction: TPE (therapeutic plasma exchange) has proven to be an extremely effective treatment for a range of conditions, especially over the past 20 years. Anticoagulation with heparin is currently the accepted recommendation for therapeutic plasma exchange sessions. However, the hypercoagulable state and hyperviscosity in some patients requiring TPE present a challenge, particularly during the first session, due to an increased risk of circuit clotting. Citrate anticoagulation has been proposed for extracorporeal therapies such as hemodiafiltration where heparin is contraindicated. Nevertheless, citrate anticoagulation is still generally avoided in patients undergoing TPE. Materials and Methods: A total of 26 patients underwent 52 TPE sessions using citrate. Fifteen patients received citrate from the beginning of therapy, accounting for 29 sessions, and eleven patients were switched to citrate after initially starting with heparin, when an imminent risk of circuit clotting quickly became evident—23 sessions in total. The imminent risk of circuit clotting was assessed by a continuous and accelerated increase in transmembrane pressure despite heparin anticoagulation. The effectiveness of citrate anticoagulation and its safety for patients were evaluated. Results: Of the 23 sessions where there was a risk of circuit clotting, citrate was added on top of heparin in those sessions; 21 sessions were successfully completed. It can be said that the kits were saved in these cases. Among the 29 TPE sessions that used citrate from the start, 27 were completed successfully, even though the patients were considered to have a hypercoagulable status. No cases of citrate toxicity were identified. Conclusions: TPE with citrate is a safe option for patients. It can preserve TPE kits from the beginning or during treatment in patients with hypercoagulability. Citrate can be also be used when heparin is contraindicated or ineffective. Full article

Cell population data (CPD) parameters generated by Sysmex XN-series analysers are promising biomarkers for a variety of disease states. Routine use of CPD parameters, however, will require extensive evaluation of potential pre-analytical variables that may affect reliability. At present, no information on the comparability of CPD parameters generated using different blood collection tubes is available. In this preliminary study, we evaluated the impact of four commonly used blood collection tubes—dipotassium (K₂) EDTA, tripotassium (K₃) EDTA, trisodium citrate, and lithium heparin—on the generation of CPD parameters in whole blood from a cohort of 10 healthy donors. We also evaluated the stability of the CPD parameters generated at 4 h post-collection. Statistically significant differences in the CPD were observed across all blood collection tubes: whole blood anticoagulated with K₃EDTA induced minimal biases and was comparable to whole blood anticoagulated with K₂EDTA at collection; however, whole blood anticoagulated with citrate and heparin were associated with more substantial and more widespread biases in several parameters with potential clinical relevance. Notably, the biases observed in whole blood anticoagulated with K₃EDTA increased in both number and magnitude at 4 h post-collection, whilst the CPD parameters generated with whole blood anticoagulated with K₂EDTA remained stable. Although further confirmatory investigations are required, these findings highlight the importance of anticoagulant selection, as well as the need for further pre-analytical research, to support the integration of CPD parameters generated by Sysmex XN-series analysers into routine diagnostic workflows. Full article

This review examines the clinical data and basic science research to evaluate the potential of the Selective Cytopheretic Device (SCD) in mitigating Extracorporeal Membrane Oxygenation (ECMO)-associated inflammation. In brief, SCD is an immunomodulatory device used within extracorporeal blood circuits along with the use of citrate anticoagulation. SCD has been shown to be a novel, first-in-its-class device (being marketed as QUELimmune by SeaStar Medical), which is capable of the autologous processing of hyper-inflamed leukocytes to reduce systemic inflammation. Strong preclinical data gathered for SCD in the context of both Cardio-Pulmonary Bypass (CPB) as well as ECMO set the stage for SCD to be used in these life support circuits. ECMO played a crucial role during the COVID-19 pandemic, during a time period when SCD therapy was being evaluated in clinical trials, generating initial clinical data in this setting. SCD has also been utilized in the setting of pediatric acute kidney injury (AKI) and multiorgan dysfunction (MOD), where ECMO can be common. Full article

This review highlights recent insights into the pathophysiology and therapeutic strategies for improving biocompatibility in hemodialysis. Hemodialysis activates the innate immune system, particularly the complement cascade and neutrophils, leading to acute microinflammation. Interleukin-8 (IL-8), which increases during dialysis, promotes neutrophil chemotaxis and neutrophil extracellular trap (NET) formation, triggering myeloperoxidase (MPO) release and oxidative stress. Neutrophil accumulation in atherosclerotic plaques exacerbates vascular inflammation through IL-6 upregulation. Elevated levels of IL-8, MPO, and NET-related biomarkers are associated with increased all-cause and cardiovascular mortality in dialysis patients. Strategies to mitigate these effects include the use of advanced membrane materials (e.g., AN69, vitamin E-coated, polymethyl methacrylate), novel dialysis modalities (e.g., high-volume online hemodiafiltration, cool dialysate, hydrogen-enriched dialysate), and citrate-based anticoagulation. These approaches aim to suppress complement activation, reduce oxidative stress, and limit neutrophil-induced damage. Enhancing biocompatibility is crucial for reducing cardiovascular complications and improving outcomes in dialysis patients. Suppressing the innate immune response during dialysis may become a future cornerstone in extracorporeal blood purification therapy. Full article

hiPSC-derived blood–brain barrier (BBB) models are valuable for pharmacological and physiological studies, yet their translational potential is limited due to insufficient cell phenotypes and the neglection of the complex environment of the BBB. This study evaluates the plasma compatibility with hiPSC-derived microvascular endothelial-like cells to enhance the translational potential of in vitro BBB models. Therefore, plasma samples (sodium/lithium heparin, citrate, EDTA) and serum from healthy donors were tested on hiPSC-derived microvascular endothelial-like cells at concentrations of 100%, 75%, and 50%. After 24 h, cell viability parameters were assessed. The impact of heparin-anticoagulated plasmas was further evaluated regarding barrier function and endothelial phenotype of differentiated endothelial-like cells. Finally, sodium-heparin plasma was tested in an isogenic triple-culture BBB model with continuous TEER measurements for 72 h. Only the application of heparin-anticoagulated plasmas did not significantly alter viability parameters compared to medium. Furthermore, heparin plasmas improved barrier function without increasing cell density and induced a von Willebrand factor signal. Finally, continuous TEER measurements of the triple-culture model confirmed the positive impact of sodium-heparin plasma on barrier function. Consequently, heparin-anticoagulated plasmas were proven to be compatible with hiPSC-derived microvascular endothelial-like cells. Thereby, the translational potential of BBB models can be substantially improved in the future. Full article

Cell-free DNA (cfDNA) analysis is a pivotal tool in non-invasive diagnostics, including cancer monitoring and prenatal testing. However, the preanalytical phase, particularly the choice of anticoagulant, significantly impacts cfDNA integrity and yield. This study aims to compare cfDNA yield, stability, and DNase activity in plasma-citrate and plasma-heparin, using plasma-EDTA and serum as established controls, to explore more deeply the impact of blood DNAse activity on cfDNA in these specimens. Blood samples from 15 healthy volunteers were collected in four types of tubes (citrate, heparin, EDTA, and serum). cfDNA was extracted and quantified using qPCR, and endogenous DNase activity was assessed through hydrolysis probe assays. Samples were incubated at 37 °C for 24 h to evaluate cfDNA degradation rates. Heparin-plasma exhibited the highest DNase activity, with baseline cfDNA levels intermediate—higher than EDTA but lower than serum—leading to substantial cfDNA degradation (85.3%). Combined with its known PCR inhibition, this renders heparin-plasma unsuitable for cfDNA analysis. Citrate-plasma, with baseline cfDNA levels similar to EDTA, showed partial DNase inhibition, resulting in intermediate cfDNA degradation (13.3%), a limitation that diminishes its viability compared to EDTA-plasma. Serum, with the highest baseline cfDNA levels, exhibited high DNase activity and significant cfDNA degradation (55.6%), making it unsuitable for cfDNA preservation. EDTA-plasma demonstrated complete DNase inhibition and minimal cfDNA degradation (8%), confirming it as the most suitable specimen for cfDNA analysis. These findings emphasize the importance of anticoagulant selection, highlighting critical limitations of heparin-plasma and citrate-plasma while reinforcing EDTA-plasma as the gold standard for preserving cfDNA integrity in diagnostic applications. Full article

Background: Aortic valve calcification results from degenerative processes associated with several pathologies. These processes are influenced by age, chronic inflammation, and high concentrations of phosphate ions in the plasma, which contribute to induce mineralization in the aortic valve and deterioration of cardiovascular health. Environmental factors, such as wood smoke that emits harmful and carcinogenic pollutants, carbon monoxide (CO), and nitrogen oxide (NO_x), as well as other reactive compounds may also be implicated. The purpose of this research was to study the impact of wood smoke on specific aortic valve characteristics, including lesion size and percentage of mineralization, in patients with aortic valve stenosis (AS). Methods: This observational study included 65 patients who underwent primary valve replacement surgery at the National Institute of Cardiology, 11 of whom were exposed to wood smoke. For each patient, approximately 0.5 cm of aortic valve tissue was collected along with a blood sample anticoagulated with sodium citrate. The valves were analyzed using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS). Since extracellular microvesicles (MVs) may induce epigenetic changes in target cells by transferring their cargo, we also analyzed their mineral content. Results: Individuals exposed to wood smoke exhibit more extensive lesion (835 µm²) characteristics compared to those with no exposure (407.5 µm²). Interestingly, FESEM images of MVs showed the presence of minerals on their surface, thus providing evidence on their possible role in the pathophysiology of mineralization. Conclusions: Our study uniquely demonstrates imaging-based evidence of structural damage and mineralization in aortic valve tissue, with chronic wood smoke exposure emerging as a significant causative factor. Full article

Extracellular nanoparticles (EPs) are a subject of increasing interest for their biological role as mediators in cell–cell communication; however, their harvesting and assessment from bodily fluids are challenging, as processing can significantly affect samples. With the aim of minimizing processing artifacts, we assessed the number density (n) and hydrodynamic diameter (D_h) of EPs directly in diluted plasma and blood using the following recently developed technique: interferometric light microscopy (ILM). We analyzed 613 blood and plasma samples from human patients with inflammatory bowel disease (IBD), collected in trisodium citrate and ethylenediaminetetraacetic acid (EDTA) anticoagulants, and 163 blood and plasma samples from canine patients with brachycephalic obstructive airway syndrome (BOAS). We found a highly statistically significant correlation between n in the plasma and n in the blood only in the human (i.e., but not canine) blood samples, between the samples with trisodium citrate and EDTA, and between the respective D_h for both species (all p < 10⁻³). In the human plasma, the average <D_h> was 139 ± 31 nm; in the human blood, <D_h> was 158 ± 11 nm; in the canine plasma, <D_h> was 155 ± 32 nm; and in the canine blood, <D_h> was 171 ± 33 nm. The differences within species were statistically significant (p < 10⁻²), with sufficient statistical power (P > 0.8). For <n>, we found no statistically significant differences between the human plasma and blood samples or between the samples with trisodium citrate and EDTA. Our results prove that measuring n and D_h of EPs in minimally processed fresh blood and in diluted fresh plasma by means of ILM is feasible for large populations of samples. Full article

Background: The International Normalized Ratio (INR) monitors anticoagulant treatment but relies on laboratory-based services. This could limit access to rapid monitoring and increase the diagnostic delay, both of which may be addressed by point-of-care testing (POCT). This study investigated the LumiraDx POC platform for INR monitoring. Methods: INR was measured on recalcified residual venous (n = 94) specimens from Chris Hani Baragwanath Hospital and capillary blood specimens (n = 254) from consenting enrolled participants at Charlotte Maxeke Johannesburg Academic Hospital Anticoagulation clinic, Johannesburg, South Africa. Standard-of-care (SOC) INR was measured on sodium-citrated venous blood using the Sysmex-CS2500 platform (Siemens Healthcare) and Neoplastin-R (Roche Diagnostics and Diagnostica Stago, Paris, France) within 2 h post-venipuncture. Within run, precision was measured using 2 LumiraDx control levels. The statistical agreement of paired INR measurements was also stratified by dosing decision. Results: The precision was within the manufacturer’s claim for controls (level 1%CV: 3.63, level 2%CV: 2.24). Accuracy analysis showed a moderate overall agreement compared to the SOC INR results with a correlation coefficient of 0.94 (95% Cl, (0.9267 to 0.9497)). The overall precision (ρ > 0.9) and accuracy (C_b = 0.9842) were good with an absolute bias of 0.07. The 95% confidence intervals for the slope and intercept did not include 1.00 and 0.00, respectively; however, the total calculated error was within the minimal acceptable limits. Conclusion: The LumiraDx INR Test showed a good performance compared to laboratory-based testing and provided opportunity for rapid and patient-centric care. Owing to an increasing positive bias for INR > 3.5, confirmation with laboratory INR measurements may be required. Full article

We developed the LabVIEW-based virtual instruments (VIs) to bridge a gap in commercial software and to enable systematic peak-overlapping studies to recognise the concentration levels enabling reliable simultaneous determination of major and minor constituents in samples with wide concentration proportions. The VIs were applied to a case study of the ion chromatographic determination of potassium as minor and sodium as a major ion with an IonPac CS12A column and 50 μL injection loop. Two successive studies based on multilevel two-factorial response surface experimental designs, (1) a model peak-overlapping study based on single-ion injections, and (2) an accuracy and precision study, provided guidelines for real sample analyses. By adjusting sample dilutions so that the sodium mass concentration was set to 340 mg/L, the simultaneous determination of potassium in the presence of sodium was possible in samples with sodium over potassium concentration ratios between 14 and 341. The relative expanded uncertainty associated with potassium ion determination was between 0.52 and 4.4%, and the relative bias was between −3.8 and 1.9%. We analysed Ringer’s physiologic solutions, standard sea, trisodium citrate anticoagulant, and buffered citrate anticoagulant solutions. We confirmed that the VI-supported peak-overlapping studies contributed to the quality of results by enabling the evidence-based choices of concentration levels adjusted by a dilution. Full article