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Hydroxyethyl Starch (hydroxyethyl + starch)
Selected AbstractsHydroxyethyl starch-induced itch: Relevance of light microscopic analysis of semi-thin sections and electron microscopyJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 3 2007Stefanie Kamann Summary Background: Hydroxyethyl starch (HES) is widely used as a plasma substitute for improving microcirculation. A major side effect of HES is severe pruritus caused by HES deposits in the skin. Since specific changes are difficult to see in paraffin sections, electron microscopy is the golden standard technique in the diagnosis of HES-induced skin disease. Our aim was to compare electron microscopic search for HES deposits with other techniques. Patients and Methods: During the last ten years, we biopsied 21 patients suspected of having HES-induced pruritus. We compared conventional microscopy with hematoxylin & eosin and toluidine blue-stained paraffin sections, toluidine blue-stained glycide ether-embedded, semithin sections and transmission electron microscopy. Results: In 9 patients specific HES deposits could be found by evaluating toluidine blue stained semithin sections by light microscopy alone. In 6 of these cases electron microscopy was also done and confirmed the findings. In contrast, no specific findings due to HES deposits could be detected by conventional histology. Conclusions: If specific HES deposits are found in toluidine blue-stained, glycide ether-embedded semithin sections, electron microscopy is not required. [source] Starch and albumin mixture as replacement fluid in therapeutic plasma exchange is safe and effectiveJOURNAL OF CLINICAL APHERESIS, Issue 5 2008Gladys P. Agreda-Vásquez Abstract Therapeutic plasma exchange (TPE) is an effective treatment in Myasthenia gravis (MG) and Guillain-Barré syndrome (GBS) and 5% human albumin is the replacement fluid of choice; however, it is expensive. More recently, it has been suggested that starch is a safe and cheaper choice to human albumin. Objective: To evaluate our 5-year experience using 3% hydroxyethyl starch (HES) and 5% human albumin mixture, as replacement fluid in TPE for these diseases. Materials and methods: Retrospective study carried out from January 2001 through September 2006. We included those patients with MG and GBS undergoing TPE. We analyzed clinical outcome (CO) and adverse events (AE) and our results were compared with a previous study which included similar patients undergoing TPE using just 5% human albumin. Results: Thirty-one procedures were carried out in 26 patients, a total of 147 TPE sessions. In the group of MG we had 57% complete responses (CR) and 86% overall response (OR) while in the group of GBS we had 40% CR and 60% OR. When we analyzed our CO with the previous study no statistical differences were found. Mean processed plasma volume (PPV) was 4.2 in MG and 5.5 in GBS. Twenty patients had AE, being hypotension and catheter dysfunction the most frequent ones, while tachycardia, hypertension and paresthesias were statistically more frequent in the HES/albumin group. Conclusions: TPE with a mixture of 3% HES and 5% human albumin is as effective and safe as 5% human albumin alone for patients with these diseases. J. Clin. Apheresis, 2008. © 2008 Wiley-Liss, Inc. [source] Hyper osmolality does not modulate natriuretic peptide concentration in patients after coronary artery surgeryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2009E. L. HONKONEN Background: The heart secretes natriuretic peptides (NPs) in response to myocardial stretch. Measuring NP concentrations is a helpful tool in guiding treatment. It has been suggested that sodium ion and hyperosmolality could affect NP excretion. If this is true, peri-operative NP measurements could be inconsistent when hypertonic solutions are used. With different osmolalities but equal volumes of hydroxyethyl starch (HES) , and hypertonic saline (HS) , infusions, this double-blinded study tested the hypothesis that osmolality modulates the excretion of NPs. Methods: Fifty coronary surgery patients were randomized to receive within 30 min 4 ml/kg either HS or HES post-operatively. Samples for analysis of atrial NP (ANP), brain NP (BNP), plasma and urine sodium and osmolality and urine oxygen tension were obtained before and 60 min after starting the infusions and on the first post-operative morning. The haemodynamic parameters were measured at the same time points. Results: Plasma osmolality and sodium increased only in the HS group. Changes in plasma BNP and ANP levels did not differ between the groups (P=0.212 and 0.356). There were no correlations between NP levels and osmolality or sodium at any time point. In the HS group, urine volume was higher (3295 vs. 2644 ml; P<0.05) and the need for furosemide treatment was less (0.4 vs. 3.8 mg; P<0.01) than in the HES group. Conclusions: The absence of effects of plasma sodium content or hyperosmolality on NP release validates the value of NPs as a biomarker in peri-operative patients. [source] Equal effects of gelatin and hydroxyethyl starch (6% HES 130/0.42) on modified thrombelastography in childrenACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2009W. A. OSTHAUS Background: Artificial colloids are frequently used to prevent or treat circulatory failure due to hypovolaemia. Whereas gelatin has been shown not to affect coagulation besides its haemodilutional effect, hydroxyethyl starches (HES) have additional negative effects on haemostasis. The third-generation HES solutions have been developed to minimise these effects. We therefore conducted a prospective, randomised study, to verify the hypothesis that a 6% HES 130/0.42/6 : 1 and a 4% gelatin infusion influences modified thrombelastography (TEM) parameters in children in the same manner and to the same extent. Methods: A total of 50 paediatric patients aged 0,12 years scheduled for surgery were assigned to receive either 10 ml/kg HES 130/0.42 or gelatin. Blood gas analysis, haemodynamic parameters and TEM measurements were performed before and after colloid administration. Results: Patient characteristics, indications/surgical procedures and the main results obtained from blood gas analysis were comparable between the two groups. After administration of either gelatin or HES, all TEM parameters, except for clotting time, indicated impaired coagulation whereas the mean values of all TEM parameters remained within the normal ranges. Comparing the gelatin and HES 130/0.42/6 : 1 groups, none of the measured TEM parameters was found to show between-group differences at baseline or after colloid infusion. Conclusion: In conclusion, we could demonstrate that the investigational product, HES 130/0.42/6 : 1 solution, administered at a dosage of 10 ml/kg to children, had comparable effects on coagulation monitored with TEM as a gelatin solution. Perioperative administration of HES 130/0.42/6 : 1 does not alter coagulation to an extent above and beyond the effect of haemodilution. [source] Fluid therapy in acute myocardial infarction: evaluation of predictors of volume responsivenessACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2009J. SNYGG Background: Static vascular filling pressures suffer from poor predictive power in identifying the volume-responsive heart. The use of dynamic arterial pressure variables, including pulse pressure variation (PPV) has instead been suggested to guide volume therapy. The aim of the present study was to evaluate the performance of several clinically applicable haemodynamic parameters to predict volume responsiveness in a pig closed chest model of acute left ventricular myocardial infarction. Methods: Fifteen anaesthetized, mechanically ventilated pigs were studied following acute left myocardial infarction by temporary coronary occlusion. Animals were instrumented to monitor central venous (CVP) and pulmonary artery occlusion (PAOP) pressures and arterial systolic variations (SPV) and PPV. Cardiac output (CO) was measured using the pulmonary artery catheter and by using the PiCCO® monitor also giving stroke volume variation (SVV). Variations in the velocity time integral by pulsed-wave Doppler echocardiography were determined in the left (,VTILV) and right (,VTIRV) ventricular outflow tracts. Consecutive boluses of 4 ml/kg hydroxyethyl starch were administered and volume responsiveness was defined as a 10% increase in CO. Results: Receiver,operator characteristics (ROC) demonstrated the largest area under the curve for ,VTIRV [0.81 (0.70,0.93)] followed by PPV [0.76 (0.64,0.88)] [mean (and 95% CI)]. SPV, ,VTILV and SVV did not change significantly during volume loading. CVP and PAOP increased but did not demonstrate significant ROC. Conclusion: PPV may be used to predict the response to volume administration in the setting of acute left ventricular myocardial infarction. [source] Characterization of amorphous solids with weak glass transitions using high ramp rate differential scanning calorimetryJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2008Derrick S. Katayama Abstract Measurement of the glass transition temperature (Tg) of proteins and other high molecular weight polymers in the amorphous state is often difficult, since the transition is extremely weak, that is, the ,Cp at the glass transition temperature is small. For example, little is known about the solid-state properties of hydroxyethyl starch (HES), which is beginning to become more commonly evaluated as a bulking agent in pharmaceutical products. For weak thermal events, such as the change in heat capacity at the Tg of a pure protein or large synthetic polymer, increased heating rate should produce greater sensitivity in terms of heat flow. Recent innovations in rapid scanning technology for differential scanning calorimetry (DSC) allow measurements on materials where the thermal events are difficult to detect by conventional DSC. In the current study, measurements of the Tg of proteins in the solid state, amorphous pharmaceutical excipients which have small ,Cp at the glass transition temperature, and bacterial spores, have all been made using high ramp rate DSC, providing information on materials that was inaccessible using conventional DSC methods. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:1013,1024, 2008 [source] Effects of annealing lyophilized and spray-lyophilized formulations of recombinant human interferon-,JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 4 2003Serena D. Webb Abstract The purpose of this study was to examine the effects of adsorption of recombinant human interferon-, (rhIFN-,) on ice surfaces and subsequent drying during processing by spray-lyophilization and lyophilization. Ice/liquid interfacial areas were manipulated by the freezing method as well as by the addition of an annealing step during lyophilization; that is, rhIFN-, adsorption was modified by the addition of nonionic surfactants. rhIFN-, was lyophilized or spray-lyophilized at a concentration of 1 mg/mL in 5% sucrose, 5% hydroxyethyl starch (HES),±,0.03% polysorbate 20 in 140 mM KCl, and 10 mM potassium phosphate, pH 7.5. After the samples were frozen, half were annealed on the lyophilizer shelf. Recovery of soluble protein was measured at intermediate points during processing. On drying, the secondary structure of rhIFN-, was determined by second-derivative infrared (IR) spectroscopy, specific surface areas (SSAs) were measured, scanning electron micrographs (SEM) were taken, and dissolution times were recorded. Adsorption of rhIFN-, to ice/liquid interfaces alone was not responsible for aggregation. Rather, drying was necessary to cause aggregation in lyophilized sucrose formulations. Addition of an annealing step to the lyophilization cycle resulted in more native-like secondary protein structure in the dried solid, eliminated cracking of the dried cakes, and suppressed both the formation of air/liquid interfaces and rhIFN-, aggregation on reconstitution. © 2003 Wiley-Liss, Inc. and the American pharmaceutical Association J Pharm Sci 92:715,729, 2003 [source] Fluid challenge in patients at risk for fluid loading-induced pulmonary edemaACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2004M. Matejovic Background:, This study evaluated the effects of protocol-guided fluid loading on extravascular lung water (EVLW) and hemodynamics in a group of patients at high risk for volume expansion-induced pulmonary and systemic edema. Methods:, Nine acutely admitted septic patients with acute lung injury (ALI) were prospectively studied. In addition to sepsis and ALI, the following criteria indicating increased risk for edema formation had to be fulfilled: increased vascular permeability defined as microalbuminuria greater than fivefold normal and hypoalbuminemia <30 g l,1. Two hundred-ml boluses of a 10% hydroxyethyl starch (HES) was titrated to obtain best filling pressure/stroke volume relation. Extravascular lung water and intrathoracic blood volume (ITBV) were measured using a transpulmonary double-indicator dilution technique. Baseline data were compared with data at the end of fluid loading and 3 h postchallenge. Results:, At study entry the mean EVLW was 13 ml kg,1, and the mean EVLW/ITBV ratio (indicator of pulmonary permeability) was 0.72 (normal range 0.20,0.30). To attain optimal preload/stroke volume relation 633 ± 240 ml of HES was needed. Fluid loading significantly increased preload (CVP, PAOP and ITBV), and stroke volume. Effective pulmonary capillary pressure (Pcap) rose only slightly. As a result, the Pcap,PAOP gradient decreased. Despite increased cardiac output, EVLW did not change by plasma expansion. Conclusion:, In this selected group of at-risk patients, the optimization of cardiac output guided by the concept of best individual filling pressure/stroke volume relationship did not worsen permeability pulmonary edema. [source] Rapid screening of polysaccharide-based plasma volume expanders dextran and hydroxyethyl starch in human urine by liquid chromatography,tandem mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 7 2008Sven Guddat Abstract The increasing number of samples and target substances in doping control requires continuously improved screening methods, combining high-throughput analysis, simplified sample preparation, robustness and reliability. Hence, a rapid screening procedure based on liquid chromatography,electrospray ionization,tandem mass spectrometry with in-source collision-induced dissociation was developed. The detection of the polysaccharide-based plasma volume expanders dextran and hydroxyethyl starch (HES) in human urine was established without further sample preparation. The in-source fragmentation strategy of the approach represented a valuable tool in the analysis of the polysaccharide-based compounds, allowing the use of tandem mass spectrometry. After direct injection of urine specimens, analytes were chromatographically separated on a monolithic reverse-phase column and detected via multiple reaction monitoring of diagnostic ions at detection limits of 10 µg/mL for HES and 30 µg/mL for dextran. Validation was performed regarding the parameters specificity, linearity, precision (8,18%) and accuracy (77,105%) and the method was applied to the investigation of approximately 400 doping control samples and seven dextran and two hydroxyethyl starch post-administration samples. The approach demonstrated its capability as a rapid screening tool for the detection of dextran and hydroxyethyl starch and represents an alternative to existing screening procedures since time consuming hydrolysis or derivatization steps were omitted. Copyright © 2008 John Wiley & Sons, Ltd. [source] Normovolemia defined according to cardiac stroke volume in healthy supine humansCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 5 2010Morten Bundgaard-Nielsen Summary Background:, Both hypovolemia and a fluid overload are detrimental for outcome in surgical patients but the effort to establish normovolemia is hampered by the lack of an operational clinical definition. Manipulating the central blood volume on a tilt table demonstrates that the flat part of the Frank-Starling curve is reached when subjects are supine and that finding may be applicable for a clinical definition of normovolemia. However, it is unknown whether stroke volume (SV) responds to an increase in preload induced by fluid administration. Methods:, In 20 healthy subjects (23 ± 2 years, mean ± SD), SV was measured by esophageal Doppler before and after fluid administration to evaluate whether SV increases in healthy, non-fasting, supine subjects. Two hundred millilitres of a synthetic colloid (hydroxyethyl starch, HES 130/0·4) was provided and repeated if a ,10% increment in SV was obtained. Results:, None of the subjects increased SV ,10% following fluid administration but there was a minor increase in mean arterial pressure (92 ± 15 to 93 ± 12 mmHg, P = 0·01), while heart rate (HR) (66 ± 12 beats min,1; P = 0·32), cardiac output (4·8 ± 1·1 l min,1; P = 0·25) and the length of the systole corrected to a HR of 60 beats/min (corrected flow time; 344 ± 24 ms; P = 0·31) did not change. Conclusion:, Supporting the proposed definition of normovolemia, non-fasting, supine, healthy subjects are provided with a preload to the heart that does not limit SV suggesting that the upper flat part of the Frank-Starling relationship is reached. [source] Equal effects of gelatin and hydroxyethyl starch (6% HES 130/0.42) on modified thrombelastography in childrenACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2009W. A. OSTHAUS Background: Artificial colloids are frequently used to prevent or treat circulatory failure due to hypovolaemia. Whereas gelatin has been shown not to affect coagulation besides its haemodilutional effect, hydroxyethyl starches (HES) have additional negative effects on haemostasis. The third-generation HES solutions have been developed to minimise these effects. We therefore conducted a prospective, randomised study, to verify the hypothesis that a 6% HES 130/0.42/6 : 1 and a 4% gelatin infusion influences modified thrombelastography (TEM) parameters in children in the same manner and to the same extent. Methods: A total of 50 paediatric patients aged 0,12 years scheduled for surgery were assigned to receive either 10 ml/kg HES 130/0.42 or gelatin. Blood gas analysis, haemodynamic parameters and TEM measurements were performed before and after colloid administration. Results: Patient characteristics, indications/surgical procedures and the main results obtained from blood gas analysis were comparable between the two groups. After administration of either gelatin or HES, all TEM parameters, except for clotting time, indicated impaired coagulation whereas the mean values of all TEM parameters remained within the normal ranges. Comparing the gelatin and HES 130/0.42/6 : 1 groups, none of the measured TEM parameters was found to show between-group differences at baseline or after colloid infusion. Conclusion: In conclusion, we could demonstrate that the investigational product, HES 130/0.42/6 : 1 solution, administered at a dosage of 10 ml/kg to children, had comparable effects on coagulation monitored with TEM as a gelatin solution. Perioperative administration of HES 130/0.42/6 : 1 does not alter coagulation to an extent above and beyond the effect of haemodilution. [source] Haemodilution induced by hydroxyethyl starches 130/0.4 is similar in septic and non-septic patientsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2008P. MEYER Background: Fluid therapy induces haemodilution related to plasma volume expansion. The aim of our study was to compare haemodilution after a single hydroxyethyl starches (HES) 130/0.4 infusion in two groups of patients, one with and one without sepsis. We hypothesized that a single HES challenge would induce similar sustained haemodilution in both groups. Methods: In this prospective preliminary study, patients predicted to require a single further volume-expander infusion were included immediately before receiving 500 ml of 6% HES 130/0.4 over a 15-min period. No additional fluid was administered over the next 8 h. Haematocrit, and serum albumin and protein were determined immediately before HES infusion then after 1, 2, 3, 4, and 8 h. Results: Twelve patients were included in each group. In both groups, all three haemodilution markers had significantly lower values after 1 h than at baseline. None of the values after 1 and 3 h differed significantly between the two groups. Neither did any of the other study variables show significant differences between the groups with and without sepsis. Conclusion: We found that a starch-based compound was as effective in inducing haemodilution in patients with sepsis as in controls without sepsis, suggesting that HES may remain within the intravascular space even in patients with sepsis. Haemodilution parameters such as haematocrit, serum albumin and serum protein are useful for assessing the duration of plasma volume expansion induced by fluid therapy in critically ill patients. [source] Colloids decrease clot propagation and strength: role of factor XIII-fibrin polymer and thrombin,fibrinogen interactionsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 8 2005V. G. Nielsen Colloid-mediated hypocoagulability is clinically important, but the mechanisms responsible for coagulopathy have been incompletely defined. Thus, my goal was to elucidate how colloids decrease plasma coagulation function. Plasma was diluted 0% or 40% with 0.9% NaCl, three different hydroxyethyl starches (HES, mean molecular weight 450, 220 or 130 kDa), or 5% human albumin. Samples (n = 6 per condition) were activated with celite, and diluted samples had either no additions or addition of fibrinogen (FI), thrombin (FIIa) or activated Factor XIII (FXIIIa) to restore protein function to prediluted values. Thrombelastographic variables measured included clot propagation (angle, ,), and clot strength (amplitude, A; or shear elastic modulus, G). Dilution with 0.9% NaCl significantly decreased ,, A and G -values compared to undiluted samples. Supplementation with FI, but not FIIa or FXIIIa, resulted in 0.9% NaCl-diluted thrombelastographic variable values not different from those of undiluted samples. FI supplementation of HES 450, HES 220, HES 130 and albumin-diluted samples only partially restored ,, A and G -values compared to undiluted samples. FIIa addition only improved clot propagation and strength in albumin-diluted samples. FXIIIa supplementation improved propagation in samples diluted with HES 450, HES 220 and albumin, and clot strength improved in HES 450 and albumin-diluted plasma. Considered as a whole, these data support compromise of FIIa-FI and FXIIIa , fibrin polymer interactions as the mechanisms by which colloids compromise plasma coagulation. Investigation to determine if clinical enhancement of FXIII activity and/or FI concentration (e.g. fresh-frozen plasma, cryoprecipitate) can attenuate colloid-mediated decreases in hemostasis is warranted. [source] | |||||||||||||