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INTRODUCTION: Enkephalins, endogenous opioid peptides, are involved in the regulation of renal function. One derived molecule, proenkephalin A, also known as penKid, has been demonstrated to be a reliable biomarker for kidney function and its plasma concentration correlates with measured glomerular filtration rate. penKid is used for prediction and diagnosis of AKI and need of renal replacement therapy (RRT). penKid has also been used to predict the successful weaning from RRT in patients with AKI. Whether the concentration of penKid is affected or not by RRT is a controversial point and there are no studies describing the kinetics of the molecule in such conditions. The low molecular weight (4.5 kDa) would imply free removal by the glomerulus and the dialysis membranes. During RRT, this reduction could not be detected in clinical practice due to the complex kinetics involving either low dialytic clearance or increased production in response to impaired kidney function. The aim of this study was to determine the sieving coefficient and the diffusive clearance of the penKid molecule in conditions of in vitro continuous veno-venous hemofiltration (CVVH) and continuous veno-venous hemodialysis (CVVHD), respectively, and also the penKid removal ratio in conditions of in vitro hemoadsorption (HA) using a synthetic microporous resin. METHODS: Blood spiked with a lyophilized penKid peptide solved in 20 m
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Adsorption-based extracorporeal therapies have been subject to technical developments and clinical application for close to five decades. More recently, new technological developments in membrane and sorbent manipulation have made it possible to deliver more biocompatible extracorporeal adsorption therapies to patients with a variety of conditions. There are several key rationales based on physicochemical principles and clinical considerations that justify the application and investigation of such therapies as evidenced by multiple ex-vivo, experimental, and clinical observations. Accordingly, unspecific adsorptive extracorporeal therapies have now been applied to the treatment of a wide array of conditions from poisoning to drug overdoses, to inflammatory states and sepsis, and acute or chronic liver and kidney failure. In response to the rapidly expanding knowledge base and increased clinical evidence, we convened an Acute Disease Quality Initiative (ADQI) consensus conference dedicated to such treatment. The data show that hemoadsorption has clinically acceptable short-term biocompatibility and safety, technical feasibility, and experimental demonstration of specified target molecule removal. Pilot studies demonstrate potentially beneficial effects on physiology and larger studies of endotoxin-based hemoadsorption have identified possible target phenotypes for larger randomized controlled trials (RCTs). Moreover, in a variety of endogenous and exogenous intoxications, removal of target molecules has been confirmed in vivo. However, some studies have raised concerns about harm or failed to deliver benefits. Thus, despite many achievements, modern hemoadsorption remains a novel and experimental intervention with limited data, and a large research agenda.
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INTRODUCTION: Per- and polyfluoroalkyl substances (PFAS) are known water pollutants leading to potential public health consequences. High blood levels of PFAS have been associated with several pathological conditions including testicular and kidney cancer. Classic extracorporeal therapies have demonstrated limited efficiency, and new approaches should be explored. In this study, we studied the possible role of hemoadsorption to achieve a fast, safe, and effective removal of PFAS from blood in patients with high blood levels. METHODS: We developed an in vitro model of hemoadsorption to test the potential of PFAS removal by extracorporeal treatment. We recirculated a highly polluted batch of water (4 L) through a sorbent cartridge (Jafron Medical, Zhuhai, China) for 120 min at a flow of 150 mL/min. We collected samples at different time points and analyzed 39 different PFAS compounds. RESULTS: For the PFAS compounds with concentrations significantly above normal, we observed a removal ratio close to 90% already within the first 60 min of circulation leading to almost complete elimination of all pollutants at 120 min. CONCLUSIONS: The in vitro model of hemoadsorption suggests the possible application in vivo of this technique to reduce/normalize the concentrations of PFAS in patients exposed to water or environmental pollution.
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Fluorocarbonos , Humanos , Fluorocarbonos/sangue , Poluentes Químicos da Água/sangue , Cinética , Adsorção , Purificação da Água/métodosRESUMO
Cartridges for hemoadsorption containing styrene-divinylbenzene sorbent are used for multiple conditions, such as intoxication. The mass transfer zone comprises the extension along the longitudinal span of the cartridge where adsorption occurs. The aim of this experiment is to evaluate the mass transfer zone for vancomycin in the HA380 cartridge. The experiment was carried out twice. A saline solution with vancomycin passed through a HA380-modified cartridge at 100 ml/min in a single-pass fashion. The cartridge had four openings along its longitudinal dimension, at 3, 6, 9, and 12 cm. In both experiments, the collection of aliquots occurred at minute 4, in the four openings and pre- and post-cartridge, and an additional sample from the effluent bag at the end of each experiment. In the second experiment, an additional sampling of the same six sites occurred at minute 14. The sigmoidal shape of the curve for the mass transfer zone of vancomycin was similar to the theoretical one. In experiment one, at minute 4, vancomycin clearance was 98.75 ml/min. In experiment two, vancomycin clearance at minutes 4 and 14 was 93.76 and 93.20 ml/min, respectively. This implies an adequate and optimal design of the HA380 cartridge.
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Vancomicina , Vancomicina/farmacocinética , Adsorção , Antibacterianos/farmacocinética , Poliestirenos , HumanosRESUMO
INTRODUCTION: Hemadsorption with new sorbent cartridges is an emerging extracorporeal blood purification technique. Flow distribution inside the sorbent is one of the main issues concerning the device's performance and optimal sorbent utilization. In this experiment, we aimed to investigate the efficacy of vibration during adsorption by measuring the removal of vancomycin. METHODS: In this experimental study, 1,000 mL of saline with 10 g of vancomycin was circulated in a closed circuit (set flow of 250 mL/min) simulating a hemadsorption blood run using HA380 minimodule cartridge containing 75 g of wet resin. This vibration model was implemented with a damping head device installed in front of the adsorption cartridge during the experiment. The kinetics of the vancomycin were assessed by removal ratio over 120 min. RESULTS: We found no difference between the two models. Adsorption with and without vibration did not differ significantly for partial reduction ratios, overall amount of adsorbed molecule, or adsorption kinetics. CONCLUSION: The current design and structure of the minimodule cartridge demonstrated no difference in small-middle solute removal. Further improvement with the addition of mechanical vibration to the device was not observed.
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Vancomicina , Vibração , Adsorção , Cinética , Hemoperfusão/métodos , Hemoperfusão/instrumentação , HumanosRESUMO
Acute decompensated heart failure and fluid overload are the most common causes of hospitalization in heart failure patients, and often, they contribute to disease progression. Initial treatment encompasses intravenous diuretics although there might be a percentual of patients refractory to this pharmacological approach. New technologies have been developed to perform extracorporeal ultrafiltration in fluid overloaded patients. Current equipment allows to perform ultrafiltration in most hospital and acute care settings. Extracorporeal ultrafiltration is then prescribed and conducted by specialized teams, and fluid removal is planned to restore a status of hydration close to normal. Recent clinical trials and European and North American practice guidelines suggest that ultrafiltration is indicated for patients with refractory congestion not responding to medical therapy. Close interaction between nephrologists and cardiologists may be the key to a collaborative therapeutic effort in heart failure patients. Further studies are today suggesting that wearable technologies might become available soon to treat patients in ambulatory and de-hospitalized settings. These new technologies may help to cope with the increasing demand for the care of chronic heart failure patients. Herein, we provide a state-of-the-art review on extracorporeal ultrafiltration and describe the steps in the development of a new miniaturized system for ultrafiltration, called AD1 (Artificial Diuresis).
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Insuficiência Cardíaca , Ultrafiltração , Humanos , Insuficiência Cardíaca/terapia , Ultrafiltração/métodos , Ultrafiltração/instrumentação , Miniaturização , Desenho de Equipamento , Hemofiltração/instrumentação , Hemofiltração/métodosRESUMO
BACKGROUND: The level of bacteremia in patients with sepsis and septic shock is a predictor of complications and mortality, regardless of the type of bacteria. Devices for bacteria, endotoxin and cytokines removal by adsorption have been recently developed. Thus, extracorporeal blood purification therapies have been proposed as adjunctive therapy in sepsis in combination with drugs. Some potentially useful drugs, however, are precluded due to their organ or metabolic toxicity. The present study represents a preliminary report on the in vitro effect of a sorbent device (minimodule with HA380 beads, Jafron medical, Zhuhai, China) in which the particles have been functionalized with vancomycin on the surface. The impact of the surface-modified beads on circulating bacteria (Staphylococcus aureus) has been tested in a simulated in vitro circulation. METHODS: In vitro experiments were carried out with 800 mL of blood enriched with S. aureus species. Blood was circulated in the vancomycin-functionalized and non-functionalized mini-module cartridges in hemoadsorption setup (300 mL each) and the bactericidal effect was assessed. Also, 200 mL of blood was used as a control. RESULTS: A significant increase in the time to positivity of blood cultures was observed after 60 min and also after 120 min of therapy with the mini-module functionalized with vancomycin as opposed to the non-functionalized cartridge. CONCLUSIONS: These results suggest a possible way of treating sepsis by using drug- or antibiotic-functionalized cartridges without worrying about pharmacological toxicity. The prolongation of the time to bacterial culture positivity to S. aureus after a passage through a column packed with beads functionalized with vancomycin represents a proof of concept.
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Bacteriemia , Sepse , Humanos , Vancomicina/farmacologia , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Sepse/tratamento farmacológico , Bacteriemia/tratamento farmacológicoRESUMO
Although the precise clinical indication for initiation of PMX-HA is widely debated in the literature, a proper patient selection and timing of treatment delivery might play a critical role in the clinical course of a specific subphenotype of septic shock (endotoxic shock). In light of this view, since 2019, we have introduced in our clinical practice a diagnostic-therapeutic flowchart to select patients that can benefit the most from the treatment proposed. In addition, we reported in this study our experience of PMX-HA in a cohort of critically ill patients admitted to our intensive care unit (ICU). We analyzed a single centre, retrospective, observational web-based database (extracted from the EUPHAS2 registry) of critically ill patients admitted to the ICU between January 2016 and May 2021 who were affected by endotoxic shock. Patients were divided according to the diagnostic-therapeutic flowchart in two groups: Pre-Flowchart (Pre-F) and Post-Flowchart (Post-F). From January 2016 to May 2021, 61 patients were treated with PMX-HA out of 531 patients diagnosed with septic shock and of these, fifty patients (82%) developed AKI during their ICU stay. The most common source of infection was secondary peritonitis (36%), followed by community-acquired pneumonia (29%). Fifty-five (90%) out of 61 patients received a second PMX-HA treatment, with a statistically significant difference between the two groups (78% of the Pre-F vs. 100% of the Post-F group, p = 0.005). In both groups, between T0 and T120, the Endotoxin Activity Assay (EAA) decreased, while the SOFA score, mean arterial pressure (MAP), and Vasoactive Inotropic Score (VIS) improved with no statistically significant difference. Furthermore, when performing a propensity score matching analysis to compare mortality between the two groups, statistically significant lower ICU and 90-day mortalities were observed in the Post-F group [p = 0.016]. Although in this experienced centre data registry, PMX-HA was associated with organ function recovery, hemodynamic improvement, and current EAA level reduction in critically ill patients with endotoxic shock. Following propensity score-matched analysis, ICU mortality and 90-day mortalities were lower in the diagnostic-therapeutic flowchart group when considering two temporal groups based on strict patient selection criteria and timing to achieve PMX. Further Randomised Control Trials focused on centre selection, adequate training and a flowchart of action when assessing extracorporeal blood purification use should be performed.
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Hemoperfusão , Choque Séptico , Humanos , Estado Terminal/terapia , Endotoxinas , Polimixina B/uso terapêutico , Estudos RetrospectivosRESUMO
In order to develop a standardized nomenclature for the mechanisms and materials utilized during extracorporeal blood purification, a consensus expert conference was convened in November 2022. Standardized nomenclature serves as a common language for reporting research findings, new device development, and education. It is also critically important to support patient safety, allow comparisons between techniques, materials, and devices, and be essential for defining and naming innovative technologies and classifying devices for regulatory approval. The multidisciplinary conference developed detailed descriptions of the performance characteristics of devices (membranes, filters, and sorbents), solute and fluid transport mechanisms, flow parameters, and methods of treatment evaluation. In addition, nomenclature for adsorptive blood purification techniques was proposed. This report summarizes these activities and highlights the need for standardization of nomenclature in the future to harmonize research, education, and innovation in extracorporeal blood purification therapies.
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Sepsis is a life-threatening syndrome initiated by a dysregulated host response to infection. Maladaptive inflammatory burst damages host tissues and causes organ dysfunction, the burden of which has been demonstrated as the paramount predictor of worse clinical outcomes. In this setting, septic shock represents the most lethal complication of sepsis and implies profound alterations of both the cardiovascular system and cellular metabolism with consequent high mortality rate. Although an increasing amount of evidence attempts to characterize this clinical condition, the complexity of multiple interconnections between underlying pathophysiological pathways requires further investigations. Accordingly, most therapeutic interventions remain purely supportive and should be integrated in light of the continuous organ cross-talk, in order to match a patient's specific needs. In this context, different organ supports may be combined to replace multiple organ dysfunctions through the application of sequential extracorporeal therapy in sepsis (SETS). In this chapter, we provide an overview of sepsis-induced organ dysfunction, focusing on the pathophysiological pathways that are triggered by endotoxin. Based on the need to apply specific blood purification techniques in specific time windows with different targets, we suggest a sequence of extracorporeal therapies. Accordingly, we reported the hypothesis that sepsis-induced organ dysfunction may benefit the most from SETS. Finally, we point out basic principles of this innovative approach and describe a multifunctional platform that allows SETS, in order to make clinicians aware of this new therapeutic frontier for critically ill patients.
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Sepse , Choque Séptico , Humanos , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/terapia , Sepse/complicações , Sepse/terapia , Choque Séptico/terapia , Estado Terminal/terapia , SíndromeRESUMO
The removal of soluble toxins from blood is necessary in patients with severe kidney failure. The majority of blood purification techniques are based on the use of semipermeable membranes, such as for dialysis treatment. But, whenever there is the need to remove small soluble molecules from blood, the use of such purification techniques may exhibit limited efficiency. This leads to a search for better-performing treatments. Hemoperfusion, given the recent strong advances in the sorption media biocompatibility with plasma (or blood), is considered a promising blood purification technique. This introductive chapter aims at briefly presenting the phenomenology of the adsorption process, also providing some basic elements related to how to use equilibrium load data to define an adsorption isotherm, which can be used to size a hemoperfusion cartridge.
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Hemoperfusão , Diálise Renal , Humanos , Diálise Renal/métodos , Adsorção , Hemoperfusão/métodos , PlasmaRESUMO
INTRODUCTION: Fluid overload and congestion are common features in patients with heart failure and are associated with negative clinical outcomes. Therapies for these conditions are diuretic-centered but frequently fail to achieve patient-adequate hydration status, prompting the use of extracorporeal ultrafiltration. Artificial Diuresis 1 (AD1) is a miniaturized, portable, and wearable system designed to deliver isolated ultrafiltration with the finest degree of simplicity and practicality. METHODS/DESIGN: Single-center, crossover, randomized, open-label pilot study to investigate the safety and the efficacy (concerning ultrafiltration accuracy) of extracorporeal ultrafiltration with the device AD1 in comparison to isolated ultrafiltration with a traditional machine (PrisMaX). Patients with chronic kidney disease stage 5D (on hemodialysis) or intensive care patients presenting acute kidney injury stage 3D (requiring hemodialysis) will carry out a single session of isolated ultrafiltration with each of the machines. The safety primary outcomes will be the occurrence of adverse events. The efficacy primary outcome will be the accuracy of ultrafiltration rate (delivered/prescribed) on each of the devices. CONCLUSION: AD1 is a novel miniaturized device for extracorporeal ultrafiltration. This study will be the first-in-human use of AD1 in patients with fluid overload.
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Insuficiência Cardíaca , Falência Renal Crônica , Humanos , Insuficiência Cardíaca/terapia , Falência Renal Crônica/terapia , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal , Ultrafiltração/métodos , Estudos Cross-OverRESUMO
Sepsis is one of the major causes of death worldwide. In its physiopathological process, a broad spectrum of pro and antiinflammatory mediators plays a strategic role, leading to a sepsis induced state of immunoparalysis. The rationale behind the employment of extracorporeal purification techniques as a complement to therapy for sepsis is based on their ability to remove the mediators involved. Until now, attention was focused on the immunomodulation allowed by purification therapies. However, the focus of studies on the application possibilities that these techniques offer as a supplement to antimicrobial therapy and resuscitation of critically ill patients must be extended. In this study, the possible removal by adsorption that the Jafron® HA330 cartridge operates against bacteria (S. aureus) was evaluated in vitro. Subsequently, it was evaluated whether the adsorptive capabilities toward bacteria were maintained by using a cartridge functionalized with Vancomycin and whether the latter maintains its bactericidal activity. This study showed that HA330 reduces the circulating bacterial load, even in the presence of pre-adsorbed Vancomycin. Vancomycin, once adsorbed by the cartridge, does not guarantee its bactericidal activity during the 2-h of hemoperfusion treatment.
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Hemoperfusão , Sepse , Humanos , Vancomicina , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Sepse/tratamento farmacológico , Sepse/microbiologia , Hemoperfusão/métodos , BactériasRESUMO
INTRODUCTION: We have recently developed a new miniaturized device for extracorporeal ultrafiltration (UF) to be used in patients with fluid overload: Artificial Diuresis-1 (AD1) (Medica S.p.A., Medolla, Italy). The device has a reduced priming volume, operates at very low pressures and flow regimes, and is designed to perform extracorporeal UF at bedside. After accurate experiments were carried out in vitro, we report in this paper the results of in vivo UF sessions carried out in selected animals according to veterinary best practice. MATERIALS AND METHODS: The AD1 kit is pre-filled with sterile isotonic solution and operates with a polysulfone mini-filter, MediSulfone (polysulfone at 50,000 Dalton). A collection bag with a volumetric scale is connected to the UF line, and the ultrafiltrate is obtained by gravity based on the height at which the ultrafiltrate collection bag is placed. Animals were prepared and anesthetized. The jugular vein was cannulated with a double-lumen catheter. Three 6-h sessions of UF were scheduled with a target fluid removal of 1,500 mL. Heparin was used as anticoagulant. RESULTS: In all treatments, the target value of UF was obtained in the absence of major clinical or technical problems with a maximum deviation from the scheduled UF rate lower than 10%. The device resulted to be safe, reliable, accurate, and easily usable thanks to a user-friendly interface and its very small dimensions. CONCLUSIONS: This study opens the way for clinical trials in different settings including departments with low intensity of care and even in ambulatory centers or patient's home.
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Diurese , Ultrafiltração , Humanos , Animais , Ultrafiltração/métodos , Anticoagulantes , ItáliaRESUMO
INTRODUCTION: Sepsis is a frequent complication in critically ill patients. Patients may require control of the source of infection, removal of pathogens and damaged cells, and organ support. Often, these targets can be achieved through the utilization of extracorporeal therapies including hemoperfusion for the adsorption of cytokines and other circulating mediators. On extracorporeal organ support, patients are generally treated with antibiotic therapy, and vancomycin is one of the most commonly used antibiotics. Because of the aspecific nature of adsorption, antibiotics can be removed from the circulation, leading to altered plasma levels and requiring prescription adjustment. The aim was to define the amount of vancomycin adsorbed by a sorbent cartridge (HA380, Jafron, China) during hemoperfusion and to establish possible strategies to maintain an effective plasma level in critically ill patients undergoing extracorporeal therapies. METHODS: In vitro experiments with incremental concentrations of vancomycin in the test solution (500 and 1,000 mL) were carried out in a recirculation circuit until sorbent saturation was observed. A maximum of 10 g of vancomycin were injected and mini-modules containing 25 g of dry resin were utilized. RESULTS: In different experiments with various concentration of vancomycin, a maximum amount of 244 mg/g of sorbent was adsorbed reaching saturation between 60 and 80 min from the beginning of the experiments. The kinetics of adsorption appears to be governed by a Langmuir-like isotherm with maximal removal speed in the early minutes and a plateau after 60 min. DISCUSSION/CONCLUSION: HA380 adsorbs significant amounts of vancomycin. Adjusting the achieved results with the experimental mini-module to a full-scale cartridge, a total of 25 g of antibiotic can be removed. This might have affected outcome results in clinical trials. This suggests prescribing administration to critically ill patients requiring hemoperfusion, immediately after or in the inter-session time window. In case of administration during hemoperfusion, adequate adjustment and plasma level monitoring is strongly recommended.
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Hemoperfusão , Humanos , Hemoperfusão/métodos , Vancomicina , Adsorção , Estado Terminal , AntibacterianosRESUMO
BACKGROUND: Extracorporeal removal of bilirubin in patients with severe liver dysfunction is a key blood purification strategy. We conducted an ex vivo study to assess the quantitative capacity to remove bilirubin from plasma of a novel adsorptive cartridge. METHODS: We studied a downscaled module of the BS330 Plasma Bilirubin Adsorption Column Cartridge (Jafron Biomedical, Zhuhai City, China) to minimize the plasma requirement in an ex vivo circulation using a solution of hyperbilirubinemic plasma. We measured the bilirubin concentration gap (ΔC) between inlet (Cpin) and outlet (Cpout) of the unit and we calculated the removal ratio (RR) as mass adsorbed at different time points. Moreover, we compared the ex vivo model with the bilirubin adsorption kinetics in a patient with acute on chronic liver failure treated with the BS330 cartridge. RESULTS: Bilirubin concentration change across the cartridge at 30 min was 16.5%, and cartridge saturation was reached at 750 min. We used a minimodule downscaled to 1:3 and containing approximately 131 g of BS330 sorbent beads: the device retained 759 mg of bilirubin with a RR of 78.1% and a RR of 42.6% at 120 min. Thus, the adsorption capacity was 5.76 mg of bilirubin per gram of sorbent. Bilirubin adsorption kinetics in our clinical case with a full-scale unit shows a coherent trend with a total bilirubin mass adsorbed after 180 min of 470 mg. DISCUSSION: Our findings provide the first assessment of bilirubin adsorption in an ex vivo model of plasma perfusion and can be used to design interventional studies in humans, providing guidance for an adequate prescription of treatment frequency and duration.
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Bilirrubina , Hemoperfusão , Humanos , Adsorção , Cinética , HiperbilirrubinemiaRESUMO
INTRODUCTION: At the time of renal replacement therapy, approximately 20% of critically ill patients have septic shock. In this study, medium cutoff (MCO) continuous venovenous hemodialysis (CVVHD) was compared to high-flux membrane continuous venovenous hemodiafiltration (CVVHDF) in terms of hemodynamic improvement, efficiency, middle molecule removal, and inflammatory system activation. METHODS: This is a monocenter crossover randomized study. Between December 31, 2017, and December 31, 2019, 20 patients with septic shock and stage 3 acute kidney injury (AKI) admitted to 2 Italian ICUs were enrolled. All patients underwent CVVHD with Ultraflux® EMiC®2 and CVVHDF with AV1000S® without washout. Each treatment lasted 24 h. RESULTS: Compared to AV1000S®-CVVHDF, EMIC®2-CVVHD normalized cardiac index (ß = -0.64; p = 0.02) and heart rate (ß = 5.72; p = 0.01). Interleukin-8 and myeloperoxidase removal were greater with AV1000S®-CVVHDF than with EMiC®2-CVVHD (ß = 0.35; p < 0.001; ß = 0.43; p = 0.03, respectively). Leukocytosis improved over 24 h in EMiC®2-CVVHD-treated patients (ß = 4.13; p = 0.03), whereas procalcitonin levels decreased regardless of the modality (ß = 0.89; p = 0.01) over a 48-h treatment period. Reduction rates, instantaneous plasmatic clearance of urea, creatinine, and ß2-microglobulin were similar across modalities. ß2-Microglobulin removal efficacy was greater in the EMiC®2 group (ß = 0-2.88; p = 0.002), while albumin levels did not differ. Albumin was undetectable in the effluent in both treatments. DISCUSSION: In patients with septic shock and severe AKI, the efficacy of uremic toxin removal was comparable between MCO-CVVHD and CVVHDF. Further, MCO-CVVHD was associated with improved hemodynamics. Fraction of filtration and transmembrane pressure reduction and the maintenance of equal efficacy might be the key features of CVVHD with MCO membranes in critically ill patients.
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Injúria Renal Aguda , Terapia de Substituição Renal Contínua , Hemodiafiltração , Choque Séptico , Humanos , Choque Séptico/terapia , Choque Séptico/etiologia , Estado Terminal , Diálise Renal , Injúria Renal Aguda/terapia , Albuminas , Hemodiafiltração/efeitos adversosRESUMO
INTRODUCTION: Medium cutoff (MCO) membranes represent an interesting innovation in the field of hemodialysis. Given the correlation between large (PM >25 kDa) middle molecules (LMM) and clinical outcomes, the possibility to broaden the spectrum of solutes removed in hemodialysis with MCO membranes introduces a new perspective for end-stage kidney disease patients. Due to low diffusion coefficients of LMM, the use of convection is required to maximize extracorporeal clearance. High convective rates are achieved with high-flux membranes in hemodiafiltration, a technique not available in the US. In case of the MCO membrane, remarkable clearances of LMM are achieved combining the permeability of the membrane with a significant amount of internal convection. The mechanism of filtration-backfiltration inside the dialyzer enables effective removal of LMM in a technique called expanded hemodialysis (HDx). Given such theoretical explanation, it is important to demonstrate the blood and ultrafiltration rheology inside the MCO dialyzer. METHOD: This study for the first time describes flow dynamic parameters and internal cross-filtration, thanks to specific radiology and nuclear imaging techniques. RESULTS: Flow dynamic analysis of the blood and dialysate compartment confirms excellent distribution of velocities and an excellent matching of blood and dialysate. Average blood flow velocity allows for wall shear rates adequate to avoid protein stagnation at the blood membrane interface and increase in blood viscosity. Cross-filtration analysis demonstrates a remarkable filtration/backfiltration flux reaching values >30 mL/min at a blood flow of 300 mL/min and zero net filtration. CONCLUSION: The MCO dialyzer Theranova 400 appears to have a design optimized to perform expanded hemodialysis (HDx).
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Hemodiafiltração , Falência Renal Crônica , Rins Artificiais , Soluções para Diálise , Humanos , Membranas Artificiais , Diálise Renal/métodosRESUMO
Sepsis-induced acute kidney injury (AKI) is a frequent complication in critically ill patients, refractory to conventional treatments. Aberrant activation of innate immune system may affect organ damage with poor prognosis for septic patients. Here, we investigated the efficacy of polymethyl methacrylate membrane (PMMA)-based continuous hemofiltration (CVVH) in modulating systemic and tissue immune activation in a swine model of LPS-induced AKI. After 3 h from LPS infusion, animals underwent to PMMA-CVVH or polysulfone (PS)-CVVH. Renal deposition of terminal complement mediator C5b-9 and of Pentraxin-3 (PTX3) deposits were evaluated on biopsies whereas systemic Complement activation was assessed by ELISA assay. Gene expression profile was performed from isolated peripheral blood mononuclear cells (PBMC) by microarrays and the results validated by Real-time PCR. Endotoxemic pigs presented oliguric AKI with increased tubulo-interstitial infiltrate, extensive collagen deposition, and glomerular thrombi; local PTX-3 and C5b-9 renal deposits and increased serum activation of classical and alternative Complement pathways were found in endotoxemic animals. PMMA-CVVH treatment significantly reduced tissue and systemic Complement activation limiting renal damage and fibrosis. By microarray analysis, we identified 711 and 913 differentially expressed genes with a fold change >2 and a false discovery rate <0.05 in endotoxemic pigs and PMMA-CVVH treated-animals, respectively. The most modulated genes were Granzyme B, Complement Factor B, Complement Component 4 Binding Protein Alpha, IL-12, and SERPINB-1 that were closely related to sepsis-induced immunological process. Our data suggest that PMMA-based CVVH can efficiently modulate immunological dysfunction in LPS-induced AKI.
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Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Ativação do Complemento/efeitos dos fármacos , Hemofiltração , Lipopolissacarídeos/efeitos adversos , Polimetil Metacrilato/administração & dosagem , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/mortalidade , Animais , Biomarcadores , Proteína C-Reativa/genética , Proteína C-Reativa/metabolismo , Modelos Animais de Doenças , Fibrose , Expressão Gênica , Hemofiltração/efeitos adversos , Hemofiltração/métodos , Humanos , Imuno-Histoquímica , Mediadores da Inflamação , Testes de Função Renal , Diálise Renal , Sepse/complicações , Componente Amiloide P Sérico/genética , Componente Amiloide P Sérico/metabolismo , Suínos , Resultado do TratamentoRESUMO
INTRODUCTION: A critical point for using blood purification during sepsis may be the potential interaction with antimicrobial therapy, the mainstay of sepsis treatment. The aim of our study was to investigate the vancomycin removal during hemoperfusion (HP) using HA380 cartridge. METHODS: This is an experimental study, in which 500 mL of solution was circulated in a closed-circuit (blood flow of 250 mL/min) simulating HP ran using HA380. Vancomycin was added to reach a through concentration or a very high concentration to evaluate the removal ratio (RR) during 120 min of HP. Comparison between blood-crystalloid solution and balanced solution was performed by using Kruskal-Wallis test. The kinetics of vancomycin removal and the adsorption isotherm were evaluated. RESULTS: We found a complete removal of vancomycin at baseline through concentration of 23.0 ± 7.4 mg/L. Using extremely high concentration (baseline 777.0 ± 62.2 mg/L), RR was 90.1 ± 0.6% at 5 min and 99.2 ± 0.6% at 120 min. No difference in terms of RR was found between blood-crystalloid mixture and balanced solution. The kinetics of the vancomycin reduction followed an exponential decay. Repeated boluses (total amount of 2,000 mg) resulted in cumulative adsorption of 1,919.4 mg with RR of 96.6 ± 1.4%, regardless of the amount injected (100 vs. 500 mg). Vancomycin adsorption onto HA380 followed the Langmuir isotherm model. CONCLUSIONS: A considerable amount of vancomycin was rapidly removed during in vitro HP with HA380. Clinical studies are needed to determine whether this may lead to underdosing. Drug therapeutic monitoring is highly recommended when using HA380 for blood purification in patients receiving vancomycin.