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Modulation of Early Inflammatory Response by Different Balanced and Non-Balanced Colloids and Crystalloids in a Rodent Model of Endotoxemia  [PDF]
Stefanie Voigtsberger, Martin Urner, Melanie Hasler, Birgit Roth Z'Graggen, Christa Booy, Donat R. Spahn, Beatrice Beck-Schimmer
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0093863
Abstract: The use of hydroxyethyl starch (HES) in sepsis has been shown to increase mortality and acute kidney injury. However, the knowledge of the exact mechanism by which several fluids, especially starch preparations may impair end-organ function particularly in the kidney, is still missing. The aim of this study was to measure the influence of different crystalloid and colloid fluid compositions on the inflammatory response in the kidney, the liver and the lung using a rodent model of acute endotoxemia. Rats were anesthetized and mechanically ventilated. Lipopolysaccharide (5 mg/kg) was administered intravenously. After one hour crystalloids [lactate-buffered (RLac) or acetate-buffered (RAc)] were infused i.v. (30 ml/kg) in all groups. At 2 hours rats either received different crystalloids (75 ml/kg of RLac or RAc) or colloids (25 ml/kg of HES in saline or HES in RAc or gelatin in saline). Expression of messenger RNA for cytokine-induced neutrophil chemoattractant-1 (CINC-1), monocyte chemotactic protein-1 (MCP-1), necrosis factor α (TNFα) and intercellular adhesion molecule 1 (ICAM-1) was assessed in kidney, liver and lung tissue by real-time PCR after 4 hours. The use of acetate-buffered solutions was associated with a significantly higher expression of CINC-1 and TNFα mRNA in the liver, in the kidney and in the lung. Only marginal effects of gelatin and hydroxyethyl starch on mRNA expression of inflammatory mediators were observed. The study provides evidence that the type of buffering agent of different colloidal and crystalloid solutions might be a crucial factor determining the extent of early end-organ inflammatory response in sepsis.
Fluid Replacement in Treatment of Hypovolemia and Shock: Crystalloids and Colloids  [cached]
Fatih Yildiz,Emre Karakoc
Arsiv Kaynak Tarama Dergisi , 2013,
Abstract: Shock is a pathologic state with high mortality rate and characterized by a reduction of systemic tissue perfusion and decresead oxygen delivery. Absolute or relative hypovolemia is a common pathology of most shock types. Correction of hypovolemia might reverse the disturbance and increase the tissue perfusion. Fluid resuscitation with crystalloid and colloid solutions can carry the risk of increasing morbidity and mortality if not used properly. Although crystalloid and colloid solutions are considered to have equal efficacy and safety profile, recent studies showed that this assumption may not be correct. Early and effective management of hypovolemia is the cornerstone of shock resuscitation. Initial management of patients with septic shock and hypovolemia should be done with 30ml/kg of crystalloids. Proper fluid replacement and resuscitation algoritms might increase the survival rate. [Archives Medical Review Journal 2013; 22(3.000): 347-361]
Effects of crystalloids and colloids on liver and intestine microcirculation and function in cecal ligation and puncture induced septic rodents  [cached]
Schick Martin Alexander,Isbary Jobst Tobias,Stueber Tanja,Brugger Juergen
BMC Gastroenterology , 2012, DOI: 10.1186/1471-230x-12-179
Abstract: Background Septic acute liver and intestinal failure is associated with a high mortality. We therefore investigated the influence of volume resuscitation with different crystalloid or colloid solutions on liver and intestine injury and microcirculation in septic rodents. Methods Sepsis was induced by cecal ligation and puncture (CLP) in 77 male rats. Animals were treated with different crystalloids (NaCl 0.9% (NaCl), Ringer’s acetate (RA)) or colloids (Gelafundin 4% (Gel), 6% HES 130/0.4 (HES)). After 24 h animals were re-anesthetized and intestinal (n = 6/group) and liver microcirculation (n = 6/group) were obtained using intravital microscopy, as well as macrohemodynamic parameters were measured. Blood assays and organs were harvested to determine organ function and injury. Results HES improved liver microcirculation, cardiac index and DO2-I, but significantly increased IL-1β, IL-6 and TNF-α levels and resulted in a mortality rate of 33%. Gel infused animals revealed significant reduction of liver and intestine microcirculation with severe side effects on coagulation (significantly increased PTT and INR, decreased haemoglobin and platelet count). Furthermore Gel showed severe hypoglycemia, acidosis and significantly increased ALT and IL-6 with a lethality of 29%. RA exhibited no derangements in liver microcirculation when compared to sham and HES. RA showed no intestinal microcirculation disturbance compared to sham, but significantly improved the number of intestinal capillaries with flow compared to HES. All RA treated animals survided and showed no severe side effects on coagulation, liver, macrohemodynamic or metabolic state. Conclusions Gelatine 4% revealed devastated hepatic and intestinal microcirculation and severe side effects in CLP induced septic rats, whereas the balanced crystalloid solution showed stabilization of macro- and microhemodynamics with improved survival. HES improved liver microcirculation, but exhibited significantly increased pro-inflammatory cytokine levels. Crystalloid infusion revealed best results in mortality and microcirculation, when compared with colloid infusion.
Prevention of Hypotension During Spinal Anesthesia: Comparison Between Preanesthetic Administration of Colloids, Crystalloids, and No Prehydration
G?nül ?lmez,M. Hadi ?ztekin
Dicle Medical Journal , 2006,
Abstract: The practice of routinely prehydrating patients for prevention of spinal anesthesia-induced hypotension has been challenged recently. The type of the solution (colloid or crystalloid) for using routine prehydration is also controversial.We compared the incidence of hypotension and vasopressor therapy during spinal anesthesia without prehydration or prehydration with crystalloid and colloid solutions in elective orthopedic surgery.Sixty ASA grade I or II patients were enrolled in the study. They were randomized to receive 500 mL 6% HES, 500 mL modified gelatin, or 1000 mL lactated ringer’s solution over 10 min prior to spinal anesthesia. Control group did not have prehydration. Hypotension was defined as a 30 % decrease of systolic blood pressure from baseline or systolic pressure detected <90 mmHg and was treated with ephedrine 5 mg boluses. Hemodynamic measurements after spinal anesthesia remained stable in prehydration groups than control. The incidence of hypotension and total dose of ephedrine use were significantly lower in colloid groups than control. Our study show that, prehydration is valuable for prevention of spinal anesthesia induced hypotension. Moreover, colloid solutions are more effective than crystalloids for minimizing the hemodynamic responses to spinal anesthesia.
Pro/con clinical debate: Hydroxyethylstarches should be avoided in septic patients
Frédérique Schortgen, Laurent Brochard, Ellen Burnham, Greg S Martin
Critical Care , 2003, DOI: 10.1186/cc1885
Abstract: A septic patient is in your intensive care unit and you are concerned that he is behind on his intravascular volume. For a variety of reasons you have decided you would like to give him intravenous colloids. The only colloid available in your intensive care unit is hydroxyethylstarch.Frédérique Schortgen and Laurent BrochardCapillary leakage during sepsis is a reason for recommending the use of macromolecules that could preserve the colloid osmotic pressure (COP). The high cost of albumin has facilitated the widespread use of hydroxyethylstarches (HES). Outcome studies on sepsis are scarce, and the reasons why we should use HES remain speculative or based on short-term physiological data. The reason why we should avoid HES is much better documented. We will briefly describe how uncertain are the clinical benefits of these products and, by contrast, how strong is the evidence for numerous adverse effects.Both crystalloids and colloids have a similar ability to achieve sufficient volume loading when the volume administered takes into account the capacity of the solution to remain in the intravascular space [1]. To achieve an equivalent plasma volume expansion, a fourfold greater volume of crystalloid may be needed in comparison with 5% albumin [1].Maintaining COP by administration of HES could, in theory, reduce pulmonary oedema. One study including septic patients found a higher incidence of pulmonary oedema after crystalloids than after HES [2]. Most clinical results have been disappointing, however, and a meta-analysis showed that pulmonary oedema occurrence is similar with colloids or crystalloids [3]. Indeed, in the context of a free course of macromolecules across a damaged alveolocapillary membrane, the Starling equation indicates that colloidal forces can no longer stop fluid shift.An attractive, although unproven, pharmacological effect of HES comes from experimental studies suggesting that HES could improve microcirculation [4]. Clinical studies were again d
Comparison of the hemodynamic effects of crystalloids and colloids in patients undergoing coronary artery bypass grefting surgery with the minimally invasive cardiac output monitoring system (Flotrac-Vigileo)  [PDF]
Halil ?eting?k,Hüseyin Uzuna?a?,Bedih Balkan,Dilek Altun
Medical Journal of Bakirk?y , 2012,
Abstract: Objective: The aim of this prospective randomized clinical trial is comparison of crystalloids and colloids's hemodynamic effects in patients undergoing elective coronary artery bypass grefting surgery with arterial pressure waveform analysis. Material and Methods: The thirty patients undergoing elective coronary arter bypass surgery were divided into two groups: crystalloid (0.9% isotonic) and 50% crystalloid (0.9% isotonic) + 50% colloid (HES 6%). FloTrac Sensor and Vigileo Monitor was attached to the arterial line. The hemodynamic parameters were recorded regarding systolic arterial pressure (SAP), diastolic arterial pressure (DAP), heart rate (HR), cardiac output (CO), stroke volume (SV), stroke volume variation (SVV). Results: There was no statistically significant difference between the two groups ragarding mean average of cardiac output and stroke volume before the induction, after the induction, after the skin incision, after the sternotomy, before the canulation, after the canulation, on-pump, after the cross clemp, after the bypass and after the chest closure (p>0.05). Only after the skin closure, the mean cardiac output and stroke volume increased in crystaloid-colloid groups compared to crystaloid group (p=0.01). Conclusion: There was no significant clinical difference between the two groups for the hemodynamic parameters in patients undergoing coronary artery bypass grefting surgery.
Pro/con debate: Should synthetic colloids be used in patients with septic shock?
James Downar, Stephen E Lapinsky
Critical Care , 2009, DOI: 10.1186/cc7147
Abstract: 'Until further data are available, synthetic colloids should not be used in critically ill patients with sepsis.'Colloid solutions are commonly used to replenish or maintain intravascular volume status in a variety of clinical settings. Human albumin is a natural and relatively safe colloid [1] but its high cost has driven a search for safe synthetic alternatives. Three types of synthetic colloids are currently used worldwide: (a) hydroxyethyl starches (HESs), (b) gelatins, and (c) dextrans.HESs are modified natural polymers of amylopectin. HES solutions are distinguished by (a) their molecular weight (MW), (b) their molar substitution ratio, and (c) their C2/C6 substitution ratio. These characteristics determine the rate of metabolism of the HES molecules, which in turn affects both the half-life and the side effects of the solution.The average MW of the HES molecules in the solution (measured in kilodaltons) is inversely correlated with colloidal activity because HES solutions are supplied in weight-based concentrations (usually 6% or 10%). Low-MW solutions contain more molecules of HES for a given concentration and thus have a higher oncotic pressure, but they have a shorter half-life in vivo because they are more quickly broken down by serum amylase to 50-kDa molecules that can be excreted in the urine. Solutions are typically divided into three weight categories: high MW (approximately 450 kDa) (for example, Hespan?), medium MW (200 to 260 kDa) (for example, HemoHES? and Pentaspan?), and low MW (70 to 130 kDa) (for example, Voluven?).To slow metabolism by amylase, HES molecules have hydroxyethyl radical groups substituted onto individual glucose units. The degree of hydroxyethyl substitution is expressed by the molar substitution ratio, which is simply a ratio of the number of substituted glucose molecules to the total number of glucose molecules. Highly substituted HES solutions have a ratio of 0.6 to 0.7 and are metabolized slowly. Less substituted HES soluti
The promise of next generation colloids
Ben C Creagh-Brown, Timothy W Evans
Critical Care , 2008, DOI: 10.1186/cc6892
Abstract: In the previous issue of Critical Care, Martini and colleagues [1] assessed the effects of haemodilution with either polyethylene glycol (PEG)ylated albumin or a commercially available hydroxyethyl starch-based colloid in a hamster haemorrhage model. The aim of perioperative haemodilution, also termed acute normovolaemic hemodilution (ANH), is to reduce loss of red blood cells during elective surgery. It involves the collection of several units of blood from the patient before the operation and substitution of an equivalent volume of plasma expander. Although surgical blood loss remains unchanged, the lost blood contains relatively fewer red blood cells and clotting factors. The patient's blood is returned to them once haemostasis is achieved. Some regard ANH to be an underused technique that can significantly reduce exposure to allogeneic blood [2]. The oncotic and molecular properties of the various plasma substitutes employed in ANH determine how effectively normovolaemia is maintained. Fluid resuscitation using colloids typically requires one-quarter to one-half the infusion volume of crystalloids [3]. Whether the advantages of colloid use in elective surgery apply equally to the critically ill, and in all such populations, is less certain. Thus, on the basis of a prospectively defined subset of trauma patients in one large-scale clinical trial of albumin versus crystalloid resuscitation [4], the former was associated with an increased risk for death. By contrast, in post hoc analysis, patients with sepsis might have benefited from albumin.The microcirculation is the primary site for gas and nutrient exchange. Perturbations in capillary perfusion may have more adverse prognostic significance [5] than traditional markers of oxygen utilization, and are implicated in the pathogenesis of organ failure in human sepsis [6]. The physicochemical attributes of the colloids determine their nononcotic effects, which include alterations in microvascular perfusion and integr
Albumin and artificial colloids in fluid management: where does the clinical evidence of their utility stand?
Johan AB Groeneveld
Critical Care , 2000, DOI: 10.1186/cc965
Abstract: The long-standing controversy regarding the optimal role of colloids in fluid resuscitation shows little sign of abating. Indeed, two recent meta-analyses have reintensified the debate [1,2]. Although investigations related to this issue have spanned four decades, many questions remain unresolved. Yet this area of clinical investigation remains highly active, and some of the most recent data on potential advantages of colloid administration have provided important new insight [3].Given the continuing accumulation of relevant clinical data, it is pertinent to ask what conclusions can now be drawn regarding the appropriate role of both natural and artificial colloids. What are the most useful endpoints for evaluating the effects of administered fluids? From the clinical standpoint, how important is COP? How similar are natural and artificial colloids in their properties? Is there conclusive evidence of differences in patient outcomes with colloids versus crystalloids? In what clinical situations might colloids offer advantages over crystalloids? These are the primary issues that this review is intended to address.Hypovolaemia is very difficult to detect at the bedside [4]. Neither hypotension nor severe tachycardia may be apparent. Stroke volume may be declining; however, this decline may go undetected unless measurements are made of this parameter. What, then, is the optimal set of fluid resuscitation endpoints that should be monitored to promote favourable patient outcomes? The definitive answer is not yet at hand. Oliguria, generally regarded as an adverse finding, might in one scenario prompt the administration of fluid. As a result, increases might be achieved in blood pressure, oxygen delivery to the tissues and, perhaps, associated oxygen consumption. These changes may be associated with increased preload recruitable stroke work, resulting in decreased lactate levels. The tonometric PCO2 gradient could also provide a useful measure of regional perfusion adequac
Fluid management and risk factors for renal dysfunction in patients with severe sepsis and/or septic shock
Laurent Muller, Samir Jaber, Nicolas Molinari, Laurent Favier, Jér?me Larché, Gilles Motte, Sonia Lazarovici, Luc Jacques, Sandrine Alonso, Marc Leone, Jean Constantin, Bernard Allaouchiche, Carey Suehs, Jean-Yves Lefrant, the AzuRéa Group
Critical Care , 2012, DOI: 10.1186/cc11213
Abstract: Among the 435 patients in a multicenter study of patients with severe sepsis and septic shock in 15 Southern French ICUs, 388 patients surviving after 24 hour, without a history of renal failure were included. Factors associated with renal dysfunction and RRT were isolated using a multivariate analysis with logistic regression.Renal dysfunction was reported in 117 (33%) patients. Ninety patients required RRT. Among study participants, 379 (98%) were administered fluids in the first 24 hours of management: HES 130/0.4 only (n = 39), crystalloids only (n = 63), or both HES 130/0.4 and crystalloids (n = 276). RRT was independently associated with the need for vasopressors and the baseline value of serum creatinine in the first 24 hours. Multivariate analysis indicated that male gender, SAPS II score, being a surgical patient, lack of decrease in SOFA score during the first 24 hours, and the interventional period of the study were independently associated with renal dysfunction. Mortality increased in the presence of renal dysfunction (48% versus 24%, P < 0.01).Despite being used in more than 80% of patients with severe sepsis and/or septic shock, the administration of HES 130/0.4 in the first 24 hours of management was not associated with the occurrence of renal dysfunction.In patients with severe sepsis and septic shock, acute renal failure (ARF) is an independent factor for mortality [1,2]. In the last decade, significant efforts were made to standardize the treatment of septic shock [3,4]. One of the most important recommendations is volume expansion that could also prevent ARF [5,6]. However, the type of fluid, especially the use of colloids, for volume expansion in septic shock remains a matter of debate [7-11]. Indeed, despite a larger plasma volume expansion power [12-14], the use of hydroxyethylstarch (HES) is not related to better outcomes when compared to isotonic crystalloids. In addition, use of HES has been associated with the development of an impaired re
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