bluuebunny/crossref_metadata_2025 huggingface dataset:
Sequential Convective Therapies (SCT): A Prospective Study on Feasibility, Safety, Adequacy and Tolerance of On-Line Hemofiltration and Hemodiafiltration in Sequence
Authors: Petras D. , Fortunato A. , Soffiati G. , Brendolan A. , Bonello M. , Crepaldi C. , Ratanarat R. , Campolo G. , Amato M. , Ronco C.
Published: January 2018

Sequential dialysis techniques (i.e pure ultrafiltration followed by dialysis) have been used in the past, due to their capability to remove large volumes of fluids without inducing hemodynamic instability. The disadvantages of inadequate efficiency and lack of technology lead to the decline of such methods. Hemofiltration (HF) and hemodiafiltration (HDF) are recently being utilized in a greater proportion thanks to on-line fluid preparation systems. Each process (HF and HDF) has its own benefits in the removal of small, medium and high-molecular weight substances and in hemodynamic stability. Sequential convective therapies (SCT) such as hemofiltration-hemodiafiltration in sequence (HF-HDF) may combine the benefits and eliminate the disadvantages of each method and should be studied in order to explore their potential application in modern dialysis. Furthermore they can be easily applied nowadays, due to the development of new sophisticated dialysis machines. In order to evaluate the feasibility, safety, efficiency and tolerance of different SCT methods we studied 3 schedules: SCT1: 1h pre-dilution HF followed by 3h of postdilution HDF (in the HF mode we lost 25% of the total fluid that had to be removed). SCT2: 1h pre-dilution HF followed by 3h of post-dilution HDF (in the HF mode we lost 50% of the total fluid that had to be removed). SCT3: 2h pre-dilution HF followed by 2h of post-dilution HDF (in the HF mode we lost 50% of the total fluid that had to be removed). We studied 6 chronic hemodialysis patients using the same machine (AK200 ULTRA), with on-line fluid preparation system and the same type of dialyzer (Polyflux 210). SCT schedules were compared to on-line HF, on-line HDF and high flux dialysis performed with the same dialyzers.

The treatments resulted safe, easy, feasible and well tolerated with an improved hemodynamic response to high volume convective therapies. Adequacy of treatment was satisfactory in all SCT schedules while middle molecular weight solute clearance and removal resulted higher in treatments with higher convective component.

SCT might represent an interesting option for the future especially in patients with hemodynamic instability and requirements for interventions during treatment.
Sleep Disorders in Hemodialyzed Patients – The Role of Comorbidities
Authors: De Santo R.M. , Lucidi F. , Violani C. , Di Iorio B.R.
Published: January 2018

Background

Sleep disorders are very frequent in hemodialyzed patients, but the relationship between these disorders and water withdrawal, urea removal and comorbidities has not been sufficiently clarified.

Methods

The study comprised a group of 88 patients in good nutritional condition, with target hemoglobin concentration, good control of blood pressure and optimal dry weight. After answering a questionnaire (SDQ) based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) patients were assigned to one of 3 groups: those with no disturbances (no. 20), those with subclinical disorders (n. 35) and insomniacs (n. 33). Yearly fluid and urea withdrawal by dialysis and the Charlson Comorbity Index were measured.

Results

Sleep disorders were observed in 77.27% of the patients. There was no difference in body fluid and urea withdrawal between groups. In the group of patients with no sleeping disturbances, the Charlson Comorbidity Index was significantly lower (p<0.001) than in patients with subclinical disorders or insomnia and emerged as a strongly associated with sleep disturbances. The study also attributes a predictive role to age, dialytic age, dialysis shift, antihypertensive drugs. The data indicate that, in evaluating sleeping disorders in patients on maintenance hemodialysis, comorbidities should be assessed.
Deviations of Placement / Function of Permanent Central Vein Catheters for Hemodialysis
Authors: Skandalos I. , Hatzibaloglou A. , Evagelou I. , Ntitsias T. , Samaras A. , Visvardis G. , Mavromatidis K. , Karamoshos K.
Published: January 2018

Fourteen cases of malposition of a permanent central vein catheter for hemodialysis or poor blood flow associated with thrombosed central veins but correct catheter positioning, in 13 patients suffering from end stage renal disease, presented from September 1991 to December 2003 among 385 permanent central vein catheters for hemodialysis (3.6%). There were 8 episodes of catheter tip malplacement in the azygos vein (1 case), hemiazygos vein (1), left internal thoracic (mammalian) vein (1), contralateral innominate vein (5) and 6 cases with correct anatomical catheter tip placement but with blood inflow from the catheter through the collateral vein system because of thrombosis of a major vein trunk (hemiazygos vein system (2), azygos vein (2), ascending lumbar veins (1), or portal vein system (1)). The malposition was diagnosed using roentgenography, with or without contrast, and computer tomography. In 3 cases the catheter was removed, in 5 cases the position was corrected. In the remaining 6 cases its function was maintained using anticoagulation or/and thrombolytic therapy. In conclusion, the placement of a permanent central vein catheter for hemodialysis must be followed by simple or contrast medium x-ray evaluation of its correct position or function. The malposition must be corrected whereas in the case where there is no alternative solution the function of the catheter may be maintained in the incorrect position using a combination of anticoagulation or/and thrombolytic therapy.
Modeling Indicator Dispersion in Extracorporeal Blood Lines
Authors: Schneditz D. , Wimmer J.
Published: January 2018

The measurement of indicators such as saline diluted by blood flow provides important information on transport characteristics during extracorporeal blood treatments. When saline is injected and measured using the extracorporeal system, the effects caused by dispersion within the extracorporeal system have to be taken into consideration in order to adequately identify intracorporeal transport characteristics. It was the aim of this study to quantify the extracorporeal contribution and to obtain a transport function for specified sections of the extracorporeal system.

The dispersion of saline following an impulsive input was measured in arterial and venous segments of customary extracorporeal blood lines with different distribution volumes (Vt=23–87 mL) using a range of different blood flows (Qb=200–450 ml/min). The dispersion was analyzed using a modified Gamma distribution function characterized by three parameters n, k, and τ, where n is real, positive, and n 1, where k=Q b/Vt*n2, and where trefers to the indicator appearance time at the sampling site. The parameters n, k, and t were identified by fitting the model function to experimental data.

The value of n was 2.3±0.5 and largely independent of the type of line segment, Qb, or Vt. τ showed a strong dependence on Vt and Qb which was described by τ= Vt/Qb*(n-1)/n.

Thus, with a given n, and when Vt and Qb are known, the transport function for saline in important sections of the extracorporeal circulation can be determined for specific experimental conditions. With this information indicator dilution curves measured in extracorporeal blood lines can be corrected for extracorporeal effects.
Fluid Dynamics Modeling of Particulate Deposition in the Lungs
Authors: Fontana D. , Vanni M. , Baldi G.
Published: January 2018

Detailed knowledge of the transport of air and particles in the human lungs is needed for two reasons: the selection of the right dosage of aerosol drugs used in respiratory therapy and the analysis of the maximum allowable concentration for particulate in air. This work is the first step of a more complex study, purpose of which is to provide some predictive relationships in order to evaluate the depth reached by the particles in the lungs as a function of their size using numerical modeling. In this phase we validated our numerical method, comparing the obtained results with those found in the literature. The Computational Fluid Dynamics code FLUENT 6 with the Eulerian-Lagrangian approach was used to simulate particle trajectories. A model of double bifurcation, based on the morphometric studies by Weibel and Hammersley and Olson, was adopted in order to represent the whole central part of the respiratory system with the same geometry, appropriately scaled down. A method to create a realistic velocity profile at the inlet of the domain was developed, in order to obtain data about particle deposition also reliable about the first bifurcation, unlike previous works.
Renal Recovery after Severe Acute Renal Failure
Authors: Bagshaw S.M. , Mortis G. , Godinez-Luna T. , Doig C.J. , Laupland K.B.
Published: January 2018

Background

There is limited information about renal recovery to independence from renal replacement therapy (RRT) and about factors associated with its occurrence after severe acute renal failure (ARF).

Methods

We conducted a population-based surveillance among all adult residents of the Calgary Health Region surviving ICU admission from May 1, 1999 to April 30, 2002. The primary objective was to determine the rate of and the factors associated with 90-day survival and recovery to independence from RRT in critically ill patients with severe ARF.

Results

At 90 days, 96 patients (40%) were alive. Of these, 72% were RRT independent with most (87%) requiring <4 weeks to recover. Prior to RRT, the median (IQR) serum creatinine and mean (SD) serum urea were 395 (252–517) μmol/L and 29.2 (18) mmol/L, respectively. Oliguria was present in 76%. Intermittent hemodialysis was the initial modality in 46% and continuous renal replacement therapy (CRRT) in 54%. By multivariate analysis, male sex (odds ratio (OR) 7.6, 95% CI, 2.2–27, p=0.01) and a diagnosis of septic shock (OR 3.9, 95% CI 1.02–14.5, p=0.05) were associated with an increased odds of recovery. Conversely, a higher Charlson co-morbidity index score (OR 0.71, 95% CI, 0.6–0.85, p=0.04) and a higher pre-RRT serum creatinine (OR 0.20, 95% CI, 0.05–0.80, p=0.02, p=0.02) were associated with reduced odds of recovery. Chronic kidney disease or the initial modality of RRT were not associated with recovery.

Conclusions

The majority of severe ARF patients who survive their acute illness are independent of RRT by 90 days. Male sex and a diagnosis of septic shock are independently associated with recovery while a greater co-morbidity score and a higher serum creatinine prior to RRT are predictive of non-recovery. (Int J Artif Organs 2006; 29: 1023–30)
Effect of On-Line Hemodiafiltration with Endogenous Reinfusion (HFR) on the Calcium-Phosphorus Metabolism: Medium-Term Effects
Authors: Bolasco P.G. , Ghezzi P.M. , Ferrara R. , Maxia M. , Pinna M. , Logias F. , Cogoni G. , Cadinu F. , Ghisu T. , Contu B. , Casu D. , Passaghe M. , Pilloni A. , Ganadu M. , Gazzanelli L.
Published: January 2018

Aim

The purpose of the study was to examine the effect of hemodiafiltration with endogenous reinfusion (HFR) compared to hemodialysis (HD) on 28 uremic patients with secondary hyperparathyroidism (2HPT) but positively selected for good and stable control of phosphatemia in order to evaluate the independent effects of dialysis treatments on bone turnover metabolism. Methods: The study was divided into 3 periods of observation: a) HD for three months; b) HFR for three months; c) HFR for a further 3 months. We analysed the trend of: whole PTH, 1–84 PTH, 7–84 PTH, alkaline phosphatase and its bone isoenzyme, total and ionised calcium, phosphatemia, dose of phosphate binder agents, β2-microglobulin, CRP. All the variations found were evaluated through mean values ± SD, t-tests, multivariate analysis.

Results

We observed a deceleration in bone turnover characterized by a reduction of the total and bone alkaline phosphatase (IU/mL) from 92.3 ± 82.8 and 35.8 ± 49.8 at the end of HD to 63.4 ± 23.9 and 16.0 ± 8.7 at the end of HFR, respectively, and 1–84 PTH from 317.5 ± 264.6 pg/mL at the end of HD to 287.5 ± 258.9 pg/mL at the end of the 3rd month of HFR. β2-microglobulin was reduced from 32.9 ± 16.1 mg/L at the end of HD to 26.4 ± 8.1 mg/L already at the end of the first three months of HFR. CRP was reduced from 2.5 ± 2.6 mg/dL at the beginning of the study to 1.3 ± 1.7 mg/dL at the end of HFR. There were no differences with regard to: dialytic efficiency, nutritional status, calcemia, phosphatemia (maintained in the K-DOQI range for the entire duration of the study), also thanks to more careful use of phosphate chelating agents.

Conclusion

We are of the opinion that HFR - essentially thanks to the use of ultrapure endogenous infusate - induces a deceleration in bone turnover due to 2PHT. In addition, phosphate substraction in HFR is better compared to HD, thanks to the improvement of the anti-inflammatory conditions by removing the cytokines harmful to bone metabolism and excluding a priori the negative effects related to hyperphosphatemia. (Int J Artif Organs 2006; 29: 1042–52)
Comparison of Specific Adsorbents for Tumor Necrosis Factor-α and Therapeutic Anti-Tumor Necrosis Factor-α Antibodies: An in Vitro Sepsis Model
Authors: Schwanzer-Pfeiffer D. , Mitteregger R. , Rossmanith E. , Falkenhagen D.
Published: January 2018

Background

Tumor necrosis factor alpha (TNF-α), as a key mediator, represents a major point of attack in sepsis. Since it has been shown that systemic anti-TNF-α antibodies do not improve the situation of septic patients, the use of specific adsorption technology in the treatment of sepsis could have beneficial effects.

Methods

Magnetic beads coated with polyclonal or with monoclonal anti-TNF-α antibodies were investigated in vitro in order to analyze their ability to prevent TNF-α induced adhesion of peripheral blood mononuclear cells (PBMCs) at human umbilical vein endothelial cells (HUVECs). Additionally, therapeutical monoclonal anti-TNF-α antibodies were proofed for inhibitory effects of TNF-α mediated activation of HUVECs.

Results

We have shown, in vitro, that beads coated with polyclonal or monoclonal anti-TNF-α antibodies were able to significantly reduce monocyte adhesion. It was possible to decrease monocyte adhesion from nearly 9% to 3% within 2 hours and from 18% to 2% within 6 hours of TNF-α treatment by the simultaneous use of beads coated with polyclonal anti-TNF-α antibodies. Beads coated with monoclonal anti-TNF-α antibodies could even prevent monocyte adhesion within the first 2 hours, and reduced monocyte adhesion to 2% during 6 hours of incubation with TNF-α. On the other hand, application of therapeutic anti-TNF-α antibodies showed no significant difference compared to the measured monocyte adhesion values of activated endothelial cells.

Conclusion

Adsorption techniques using specific adsorbents, possibly used in MDS (Microspheres-Based Detoxification System), are efficient in specific reduction of TNF-α and pathophysiological consequences, since monocyte adhesion at activated HUVECs was shown to be reduced. (Int J Artif Organs 2006; 29: 1140–7)
Tribological Characterization of Surface-Treated Commercially Pure Titanium for Femoral Heads in Total Hip Replacement: A Feasibility Study
Authors: Cotogno G. , Holzwarth U. , Franchi M. , Rivetti S. , Chiesa R.
Published: January 2018

Most noncemented total hip replacements combine a titanium alloy stem, a CoCrMo femoral head and an ultra-high molecular weight polyethylene (UHMWPE) acetabular cup. In spite of its nickel content of up to 1% and the resulting biocompatibility issues in some clinical situations, the higher cost and some difficulties in machining, CoCrMo alloy is preferred to titanium alloys thanks to its outstanding tribological properties, higher hardness and elastic modulus. Nowadays most of the heads of hip prostheses use CoCrMo as bearing material.

The present study investigates the effect of various surface treatments and combinations of treatments, such as electrochemical oxidation (anodization), laser surface melting and barrel polishing, on the tribological properties of commercially pure grade 2 titanium. The aim of the study was to characterize surface treatments capable of improving the tribological properties of titanium surface to the same extent as CoCrMo. The tribological properties were characterized by multidirectional pin-on-flat screening wear tests, using UHMWPE pins as bearing surface. The experiments showed the possibility of improving the wear resistance of titanium to the degree of CoCrMo. Although further efforts will be required to optimize the treatments studied, the results are encouraging enough to warrant pursuing this direction of investigation.
Hemolysis Evaluation of Centrifugal Pumps Using Microcapsule Suspension
Authors: Ootaki Y. , Kamohara K. , Horvath D.J. , Massiello A. , Golding L.A.R. , Lukic B. , Weiss W.J. , Maruyama O. , Fukamachi K.
Published: January 2018

Objectives

Bovine and human blood has been widely used for in vitro hemolysis testing to evaluate centrifugal cardiac assist pumps. However, results from such tests are complicated by variations in the susceptibility of individual red blood cells to shear. The objective of this study was to evaluate the use of microcapsule suspension as an alternative to bovine or human blood for hemolysis testing.

Methods

Microcapsule suspensions of 100 μm maximal diameter (average 79.1 μm) with a polyurethane membrane were used. Each microcapsule contained a leuco dye, which was used to measure “hemolysis” in the suspension after exposure to mechanical stress. Six centrifugal pumps were used to measure and compare the hemolysis values of microcapsule suspensions, bovine blood and human blood.

Results

Correlations were significant between the hemolysis values measured using microcapsule suspensions and those using bovine blood (R = 0.965, p = 0.002) and human blood (R = 0.940, p = 0.005).

Conclusions

Microcapsule suspension can be successfully used instead of blood to compare the relative hemolytic performance of centrifugal blood pumps.
Digoxin Transport by Renal Proximal Tubule Cells is Enhanced by Adhesive Synthetic RGD Peptide
Authors: Ijima H. , Kuroda S. , Ono T. , Kawakami K.
Published: January 2018

Introduction

The dialyzer apparatus has been widely used as an artificial kidney in medical treatment. However, side effects such as amyloidosis have occurred during long-term treatment. Therefore, we focused on developing a hybrid artificial kidney with a filtration and reabsorption apparatus, but it was found that cells spread extensively and it is difficult to maintain a uniform monolayer with a regular cell shape on a collagen-coated substrate. The purpose of this study was to improve cell adhesion, uniform stable monolayer formation and active transport function by immobilization of arginine-glycine-aspartic acid (RGD) on the culture substratum.

Materials and Methods

Polycarbonate semipermeable membranes were coated with collagen, fibronectin, laminin and synthetic polypeptide, including RGD (Pronectin F). Cell adhesion and digoxin transport were estimated using a renal proximal tubule cell line that overexpressed the P-glycoprotein gene.

Results and Discussion

Under initial and confluent conditions, immobilized cell density in Pronectin F-coated wells was higher than that under other conditions. Transepithelial electrical resistance and digoxin transport activity on Pronectin F-coated membranes were the highest of all conditions. This might have been caused by uniform cell morphology and high cell density.
In Vitro Evaluation of an Axial Flow Pump: Mock-Pump Interaction and an Approach to Control
Authors: Camus J.M. , Campomar G. , D'Attellis C. , Silvestrini M. , Varela L. , De Forteza E.
Published: January 2018

Continuous flow pump support has emerged as an alternative therapy in patients with congestive heart failure. For long-term applications, it is important to have a control system that changes the pump function according to the physiological conditions of the patient, thereby preventing risk situations. In the early stages of development, the evaluation of control algorithms for artificial blood pumps can be done in vitro using cardiovascular mock systems.

A systemic cardiovascular mock loop was constructed and an axial flow pump was connected to it. The level of pump assistance was estimated using a pulsatility index (IPAo) obtained from the aortic pressure wave. An IPAo proportional-integral control system was implemented and its responses to peripheral resistance and systemic compliance changes were evaluated.

IPAo is an indicator of the assistance level of a continuous flow pump operated at constant speed.

The IPAo control algorithm responds by increasing the pump speed when peripheral resistance or systemic compliance is reduced. Control system operation around an IPAo fixed value provides a safety point for pump operation by maintaining aortic pressure pulsatility and avoiding ventricular suction. In vitro experimental results show that the IPAo can be taken into consideration in multiobjective control algorithm designs.
Nonisothermal Reactors for the Production of Pure Water from Peritoneal Dialysis Waste Waters
Authors: Diano N. , Ettari G. , Grano V. , Gaeta F.S. , Rossi S. , Bencivenga U. , D'Alterio C. , Ruocco G. , Mita L. , Santo De N.G. , Canciglia P. , Mita D.G.
Published: January 2018

The diffusion of peritoneal dialysis (PD) at home is somewhat restricted by the difficulty of transport and storage of a large amount of dialytic solutions. This problem is exacerbated in the case of hemodialysis. With the aim of producing pure water to be used in preparing the solution for peritoneal dialysis, or for hemodialysis in general, as one example, we purified the spent dialysate solution from PD. Experiments were carried out with 24 dialysate solutions taken from 8 patients. Pure water was obtained by means of a thermodialysis process in a hollow fiber reactor operating under nonisothermal conditions. Results show that the yield of the nonisothermal process is dependent on the temperature difference applied across the hydrophobic membranes. The production of pure water per square meter of membrane and per hour was equal to 0.55 or 1.2 or 2.0 liters, with a temperature difference of 11°C or 21°C or 28°C, respectively. These results encourage the use of the thermodialysis process in the production of pure water for clinical uses
Renal Replacement Therapy for Acute Kidney Injury: Let's follow the Evidence
Authors: Ronco C.
Published: January 2018

Selection of a dialysis modality for critically ill patients with acute kidney injury (AKI) continues to be a controversial topic. Available studies can be divided into: 1) randomized controlled trials assessing the effect of treatment dose on patient outcome; 2) randomized controlled outcome comparisons of CRRT and IRRT; and 3) observational outcome comparisons of CRRT and IRRT Clinical outcome comparisons of CRRT and HD continue to be very problematic. With the availability of the recent CRRT dose/outcome data, the interpretation of CRRT vs HD trial data now becomes nearly impossible because of the low-dose “handicap” that has existed in all of the comparative trials in the CRRT arms. Randomized and observational outcome studies suffer from several methodological problems and a final statement cannot be made. In the end, CRRT and HD are vastly different therapies that are not mutually exclusive but rather are complementary - they provide different options for patients at variable stages of their AKI course. Very preliminary data from SLED studies suggest this therapy also can be part of the continuum of AKI dialytic modalities. However, the lack of any meaningful outcome data for this therapy invalidates any claims of clinical “equivalence” to the other established modalities.
Nanofibrous Poly(ε-Caprolactone)/Poly(Vinyl Alcohol)/Chitosan Hybrid Scaffolds for Bone Tissue Engineering using Mesenchymal Stem Cells
Authors: Mohammadi Y. , Soleimani M. , Fallahi-Sichani M. , Gazme A. , Haddadi-Asl V. , Arefian E. , Kiani J. , Moradi R. , Atashi A. , Ahmadbeigi N.
Published: January 2018

In the present study, based on a biomimetic approach, novel 3D nanofibrous hybrid scaffolds consisting of poly(ε-caprolactone), polyvinyl alcohol), and chitosan were developed via a multi-jet electrospinning method. The influence of chemical, physical, and structural properties of the scaffolds on the differentiation of mesenchymal stem cells into osteoblasts, and the proliferation of the differentiated cells were investigated. Osteogenically induced cultures revealed that cells were well-attached, penetrated into the construct and were uniformly distributed. The expression of early and late phenotypic markers of osteoblastic differentiation was upregulated in the constructs cultured in osteogenic medium.
Continuous Renal Replacement Therapy in Neonates and Young Infants during Extracorporeal Membrane Oxygenation
Authors: Cavagnaro F. , Kattan J. , Godoy L. , González A. , Vogel A. , Rodríguez J. I. , Faunes M. , Fajardo C. , Becker P.
Published: January 2018

Extracorporeal membrane oxygenation (ECMO) is a therapy that ensures adequate tissue oxygen delivery in patients suffering cardiac and/or respiratory failure that are unresponsive to conventional therapy During ECMO, it is common to see a decrease in urine output that may be associated with acute renal failure. In this context, continuous renal replacement therapy (CRRT) should be considered. Our aim is to evaluate a pioneer experience in Latin America, related to the use of CRRT in a group of neonatal-pediatric patients during ECMO. We conducted a retrospective review of patients treated with ECMO at our institution between May 2003 and May 2005. Twelve infants were treated with ECMO, six of them also underwent CRRT. The main reasons for CRRT initiation were fluid overload and progressive azotemia. Observed complications were clots in the filter and excessive ultrafiltration. CRRT was successful in fluid management and solute clearance in all patients. Discharge survival rate was 83%, all of them with normal renal function. Concurrent CRRT with ECMO is technically feasible and efficacious in the management of fluid overload and solute clearance. We report the first experience with these therapies in a Latin American neonatal-pediatric ECMO program associated with the Extracorporeal Life Support Organization.
Extracorporeal Membrane Oxygenation and Extracorporeal Albumin Dialysis in Pediatric Patients with Sepsis and Multi-Organ Dysfunction Syndrome
Authors: Tiruvoipati R. , Moorthy T. , Balasubramanian S.K. , Platt V. , Peek G. J.
Published: January 2018

Extracorporeal membrane oxygenation (ECMO) is used in managing patients with potentially reversible cardio-respiratory failure refractory to conventional methods. Multiorgan dysfunction syndrome (MODS), usually due to sepsis, remains the main cause of mortality in such patients. We report a series of six pediatric patients with sepsis-induced MODS where extracorporeal albumin dialysis (EAD) was used while the patients were on ECMO. The age of the patients ranged between 1 month and 17 years. The mean pediatric index of mortality (PIM) score at admission was 67.5%. All these patients further deteriorated with MODS and EAD was used as rescue therapy. At institution of EAD, 4 patients had dysfunction of 4 organs and 2 patients had dysfunction of 5 organs. The number of EAD cycles ranged between 1 and 3. Three out of the 6 patients (50%) survived to discharge from the intensive care unit and two of the six patients (33%) survived to hospital discharge. According to our previous experience and published results, all these patients would have been expected to die. The present results suggest that EAD may prove to have a role in the treatment of pediatric patients with sepsis-induced MODS. Further research is required to identify the group of patients who would benefit most by EAD as well as understand the clearance of inflammatory mediators and other mechanisms involved with the use of EAD.
Continuous Hemofiltration dose Calculation in a Newborn Patient with Congenital Heart Disease and Preoperative Renal Failure
Authors: Ricci Z. , Polito A. , Giorni C. , Di Chiara L. , Ronco C. , Picardo S.
Published: January 2018

Objective

To report a case of a newborn patient with renal failure due to polycystic kidneys requiring renal replacement therapy, and total anomalous pulmonary venous return requiring major cardiosurgical intervention.

Setting

Pediatric cardiosurgery operatory room and pediatric cardiologic intensive care. Patient: A 6-day-old newborn child weighing 3.1 kg.

Results

Renal function (creatinine value and urine output) was monitored during the course of the operation and intraoperative renal replacement therapy was not initiated. Serum creatinine concentration decreased from 4.4 to 3 mg/dL at cardiopulmonary bypass (CPB) start and to 1.5 at the end of surgery: the creatinine decrease was provided by the dilutional effect of CPB priming and the infusion of fresh blood from transfusions together with an adequate filtration rate (800 m/L in about 120 minutes). After the operation, extracorporeal membrane oxygenation (ECMO) for ventricular dysfunction and continuous hemofiltration for anuria refractory to medical therapy were prescribed. The hemofiltration machine was set in parallel with the ECMO machine at a blood flow rate of 60 ml/min and a predilution replacement solution infusion of 600 ml/h (4.5 ml/min of creatinine clearance once adjusted on extracorporeal circuits; 3000 mL/m2 hemofiltration): after a single hemofiltration session lasting 96 hours, serum creatinine reached optimal steady state levels around 0.5 mg/dL on postoperative day 2 and 3.

Conclusion

Administration of intraoperative continuous hemofiltration is not mandatory in the case of a 3-kg newborn patient with established renal failure needing major cardiosurgery: hemodilution secondary to CPB, transfusion of hemoderivates, and optimal UF rate appear to be effective methods for achieving solute removal. If postoperative continuous hemofiltration is started, however, a “dialytic dose” of 4.5 ml/min allows an adequate creatinine clearance, quick achievement of a steady state of serum creatinine concentration and an eventual acceptable rate of inflammatory mediator removal.
A Pilot Randomized Controlled Crossover Study Comparing Regional Heparinization to Regional Citrate Anticoagulation for Continuous Venovenous Hemofiltration
Authors: Fealy N. , Baldwin I. , Johnstone M. , Egi M. , Bellomo R.
Published: January 2018

Objective

To evaluate the efficacy and safety of a regional heparinization and a regional citrate method of anticoagulation in CVVH.

Design

Randomized controlled cross-over study

Subjects

Ten critically ill patients with acute renal failure

Setting

ICU of tertiary hospital

Intervention

CVVH was performed with pre-filter fluid replacement at 2000ml/h and a blood flow rate of 150ml/min. Regional heparinization was by the administration of heparin pre-filter at 1500IU/h and protamine post-filter at 15mg/h. Regional citrate anticoagulation was by means of a citrate-based replacement fluid (14 mmol/L) administered pre-dilution.

Results

We studied nine males and one female. The mean age and APACHE II score were 70.5 and 17 respectively. Median circuit life was 13 hours (IQR 9.28) for the regional heparinization method compared to 17 hours (IQR 12,19.5) for the regional citrate method (p=0.77). There were no episodes of bleeding in either group.

Conclusion

Regional heparinization and regional citrate anticoagulation achieve similar circuit life in critically ill patients receiving CVVH.
Evaluation of the Polyflux® 6H Dialyzer in Pediatric Patients Receiving Maintenance Hemodialysis
Authors: Goldstein S. L. , Allsteadt A. , Beck W. , Nilsson L.-G.
Published: January 2018

Hemodialysis remains the only life sustaining maintenance renal replacement therapy option for children who cannot undergo expeditious renal transplantation or who are not medical candidates for peritoneal dialysis. Provision of maintenance hemodialysis to small children entails many challenges, which arise from the limited choices for appropriately sized disposable dialysis treatment components. The dialysis extracorporeal circuit volume, comprised of the blood tubing and dialyzer, should be low enough to prevent hypotension and prevent the need for repeated blood transfusions. We performed a market acceptance evaluation of the Polyflux® 6H dialyzer (0.6 m2 membrane surface area; Gambro® Renal Products, Lakewood, Colorado) in six pediatric patients (3 male, 3 female, mean weight 24.4+6.5 kg, mean age 10.3+3.8 yrs). We found that the Polyflux® 6H Dialyzer provided a trend for improved clearance compared to Fresenius F3 and F4 dialyzers. We found that the Polyflux® 6H Dialyzer provided adequate clearance for children up to 24 kg in size and is a suitable dialyzer choice for patients 13 to 26 kg in size.
A New Method to Evaluate Patient Characteristic Response to Ultrafiltration during Hemodialysis
Authors: Casagrande G. , Teatini U. , Romei Longhena G. , Miglietta F. , Fumero R. , Costantino M.L.
Published: January 2018

Background.

Several factors are involved in the pathogenesis of dialysis discomfort interfering with optimal fluid removal and reducing the efficacy of the treatment; the most important one is a decrease in blood volume caused by an imbalance between ultrafiltration (UF) and plasma refilling (PR) rates.

Objectives.

This study is aimed at devising a method to tailor the dialysis therapy to each individual patient, by analyzing the relationship between PR and UF during the sessions in stable patients and widening the knowledge of fluid exchanges during the treatment.

Methods.

Thirty stable patients undergoing maintenance hemodialysis were enrolled. Three dialysis sessions were monitored for each patient; systemic pressure, blood composition, blood volume % variation, weight loss and conductivity were recorded repeatedly. A Plasma Refilling Index (PRI), defined and calculated by means of parameters measured throughout the dialysis, was introduced as a novel instrument to study plasma refilling phenomena.

Results.

The PRI provides understanding of patient response (in terms of plasma refilling) to the set UF. In the monitored sessions, the PRI trend is found to be characteristic of each patient; a PRI course that is at variance with the characteristic trend is a signal of inadequate or unusual dialysis scheduling. Moreover, statistical analysis highlights two different PRI trends during the first hour and during the rest of the treatment, suggesting the presence of different treatment phases.

Conclusion.

The main advantage of the PRI index is that it is non-invasive peculiar to each patient and easy to compute in a dialysis routine based on online data recorded by the monitor. A deviation from the characteristic trend may be a warning for the clinician. The analysis of the PRI trend also suggests how to modulate UF as a function of interstitial to intravascular fluid removal balance during dialysis.
The use of Peritoneal Mesothelium as a Potential Source of Adult Stem Cells
Authors: Gotloib L. , Gotloib L.C. , Khrizman V.
Published: January 2018

At the dawn of the 21st century, classical curative medicine is being challenged by the fact that efforts to fight and prevent not a few diseases, are in many circumstances, beyond the power of the pharmacological armamentarium of the medical profession. On the other hand, replacement of lost function by mechanical or biophysical devices, or even by organ transplantation, prolongs life but generally derives in new and, at times, unsolvable problems.

Regenerative therapy using stem cells began a revolutionary trend that may well change both the therapeutic approach to not a few of the diseases resulting from failing organs, as well as the fate and quality of life of millions of patients.

The presence of pluripotent mesenchymal cells in the mesothelial monolayer as well as in the submesothelial connective tissue raises the possibility of using the peritoneal mesothelium in regenerative therapies. This perception of the problem is also based on observations made in humans as well as in laboratory animals showing bone, bone marrow, cartilaginous tissue, glomerular-like structures and creation of blood conducts, pathological situations (mesothelioma, sclerosing peritonitis), or after in vivo or ex vivo experimental interventions. The main concept emerging from this information is that peritoneal mesothelial cells are endowed with such a degree of plasticity that, if placed in the appropriate micro-environment, they have a remarkable potential to generate other mesenchymal-derived cell lines.

Intensive research is required to define the best environmental conditions to take advantage of this plasticity and make the peritoneal mesothelium an actual option to be applied in regenerative medicine.
Mesothelial Cell Transplantation in Myocardial Infarction
Authors: Elmadbouh I. , Michel J.-B. , Chachques J.C.
Published: January 2018

Mesothelial cells (MCs) are accessible in human patients by excision and digestion of epiploon or from peritoneal fluid or lavage. MCs are easy to culture to obtain large quantities in vitro and they can be genetically modified with interesting therapeutic genes. The important potential of MCs in tissue engineering has been shown during epiplooplasty to different organs and also in creating artificial blood conduits. MC of epicardium is probably the precursor of coronary arteries during embryogenesis. MCs secrete a broad spectrum of angiogenic cytokines, growth factors and extracellular matrix, which could be useful for repairing damaged tissues. MCs are transitional mesodermal-derived cells and considered as progenitor stem cell, have similar morphological and functional properties with endothelial cells and conserve properties of transdifferentiation. MC therapy in myocardial infarction induced neoangiogenesis in infarcted scar and preserved heart function. In conclusion, a potential therapeutic strategy would be to implant or re-implant genetically modified MCs in post-infarction injury to enhance tissue repair and healing. Imparting therapeutic target genes such as angiogenic genes would also be useful for inducing neovascularization.
Effect of Two-Hour Daily Hemodialysis and Sham Dialysis on Breath Isoprene Exhalation
Authors: Capodicasa E. , Brunori F. , De Medio G.E. , Pelli M. A. , Vecchi L. , Buoncristiani U.
Published: January 2018

Background

Isoprene, a volatile hydrocarbon produced by the human organism, is currently being extensively investigated because the mechanisms underlying its endogenous origin are unknown and because experiments suggest it is toxic and cancerogenous. Previous reports of increases in breath isoprene concentrations during 4-hour, thrice-weekly hemodialysis, but not during continuous ambulatorial peritoneal dialysis, prompted us to assess the behavior of isoprene in another dialytic modality, i.e., short daily hemodialysis (short DHD). Furthermore, in order to determine whether removal of solutes and/or contact of blood with the dialytic membrane influenced the metabolism of isoprene, we performed a sham short hemodialysis session in a subgroup of 8 patients (sham short HD), i.e., with blood flowing through a dialyzer but without dialysate and ultrafiltration.

Methods

The present study evaluates the effects of a two-hour short DHD and a two-hour session of sham HD on isoprene breath levels, as determined by gas chromatography before, during and after sessions. Parallel analyses of ambient air and monitoring of blood pressure and heart rate were performed.

Results

Both short DHD and sham DHD induced an increase in breath isoprene exhalation in all patients without being associated with significant hemodynamic variations.

Conclusion

These findings suggest that the increase in breath isoprene after a session of hemodialysis is neither a reaction to mevalonate depletion nor to metabolic variations induced by the depurative effect, because these changes do not occur during sham HD. It is not related to hemodynamic changes because none were observed in this experimental model. The isoprene increase seems to be of metabolic origin and appears to be connected in some way with the extracorporeal circuit. These interesting findings provide a further impulse to study the biosynthetic pathways involved and to investigate the medical and biological significance of isoprene in humans. (Int J Artif Organs 2007; 30: 583–8)
Performance Study on Newly Developed Impellers for a Left Ventricular Assist Device
Authors: Hsu C-H.
Published: January 2018

Our research develops a performance study on newly developed impellers for a left ventricular assist device. In order to analyze the hemodynamic characteristics of blood flow through the ventricular assist device, the CFX-TASCflow software is adopted to investigate the flow-field characteristics. The numerical results provide not only the flow characteristics for the overall field, but also the data of relationship for flow rate and pressure head. In the conceptual design process, hemodynamic study for an initial impeller design is presented first and a geometry change is recommended. Two design models are developed and the associated flow rate and pressure head performances are evaluated as well. According to design criteria, the most efficient design is the one with a smooth flow passage and with a low possibility for vortex generation. We suggest the superior design be chosen for further in vitro testing and be prepared for the new design generation. It has been shown that the design can provide a flow rate of 3.0 l/min with a pressure head of 127.09 mmHg. Both the flow rate and pressure head can meet requirements for the left ventricular assist device to work normally. (Int J Artif Organs 2007; 30: 594–603)
Bacterial Communications in Implant Infections: A Target for an Intelligence War
Authors: Costerton J.W. , Montanaro L. , Arciola C.r.
Published: January 2018

The status of population density is communicated among bacteria by specific secreted molecules, called pheromones or autoinducers, and the control mechanism is called “quorum-sensing”. Quorum-sensing systems regulate the expression of a panel of genes, allowing bacteria to adapt to modified environmental conditions at a high density of population.

The two known different quorum systems are described as the LuxR-LuxI system in gram-negative bacteria, which uses an N-acyl-homoserine lactone (AHL) as signal, and the agr system in gram-positive bacteria, which uses a peptide-tiolactone as signal and the RNAIII as effector molecules. Both in gram-negative and in gram-positive bacteria, quorum-sensing systems regulate the expression of adhesion mechanisms (biofilm and adhesins) and virulence factors (toxins and exoenzymes) depending on population cell density.

In gram-negative Pseudomonas aeruginosa, analogs of signaling molecules such as furanone analogs, are effective in attenuating bacterial virulence and controlling bacterial infections. In gram-positive Staphylococcus aureus, the quorum-sensing RNAIII-inhibiting peptide (RIP), tested in vitro and in animal infection models, has been proved to inhibit virulence and prevent infections. Attenuation of bacterial virulence by quorum-sensing inhibitors, rather than by bactericidal or bacteriostatic drugs, is a highly attractive concept because these antibacterial agents are less likely to induce the development of bacterial resistance.
Peritoneal Dialysis-Related Peritonitis: Can We Predict It?
Authors: Chow K. M. , Li P. K.-T.
Published: January 2018

Peritonitis complicating peritoneal dialysis represents a major cause of technique failure, hospitalization, and increased mortality. Peritonitis tends to be recurrent and clustered within particular patients at risk. The aim of this review is to evaluate the potential predictive factors for development of peritoneal dialysis-associated peritonitis based on currently available evidence. Risk factors were divided into medical and non-medical ones, and characterized by a schema of fixed versus modifiable factors. A new direction in the landscape change of the risk factors of peritonitis appears to focus on psychosocial aspects and patient training. Identification of these factors have important clinical implications because of the hitherto lack of well-established strategies to prevent peritonitis complicating peritoneal dialysis. It is hoped that better understanding of the risk factors will allow us to take tangible steps toward minimizing the infectious burden from the Achilles' heel of peritoneal dialysis.
Antimicrobial Coating of Devices for Prevention of Infection: Principles and Protection
Authors: Darouiche R. O.
Published: January 2018

Device-associated infections are responsible for about half of nosocomial infections and can cause major medical and economical sequelae. Despite adherence to basic infection control measures, which constitute the mainstay for preventing infection, infections associated with certain devices continue to exist at unacceptably high rates. Potentially-preventive, antimicrobial-utilizing strategies include systemic antibiotic prophylaxis and local administration of antimicrobial agents (antibiotics or antiseptics), which includes antimicrobial irrigation of the surgical field, placement of antimicrobial carriers, antiseptic cleansing of the skin, dipping of surgical implants in antimicrobial solutions, and inserting antimicrobial-coated implants. Since bacterial colonization of the indwelling device is a prelude to infection, prevention of device colonization may lead to a lower rate of clinical infection. Different approaches for antimicrobial coating of devices have been variably successful in preventing device-associated infections. Optimal characteristics of antimicrobial coating can help predict the likelihood and degree of clinical protection against infection. This review addresses the impact of device-related infection, antimicrobial-utilizing approaches for preventing infection, clinical protection afforded by different types of antimicrobial coating, characteristics that predict the ability of antimicrobial coating of devices to prevent clinical infection, and future directions of antimicrobial coating.