Effect of a nitric oxide donor on maternal hemodynamics in fetal growth restriction

OBJECTIVE

To evaluate the effect on maternal cardiovascular parameters of treatment with a nitric oxide (NO) donor and plasma volume expansion in pregnancies complicated by fetal growth restriction (FGR).

METHODS

Twenty-six pregnant women with a diagnosis of FGR were treated with transdermal patches of a NO donor and plasma volume expansion by co-administration of oral fluids. We compared the treated group to a historical control group of untreated FGR patients. Hemodynamic indices were obtained using the UltraSonic Cardiac Output Monitor system.

RESULTS

At diagnosis, the two groups were similar in terms of maternal and hemodynamic characteristics. In the treated group, we found a significant increase in maternal cardiac output and stroke volume and a decrease in systemic vascular resistance after 2 weeks of therapy. No significant differences were found 2 weeks after diagnosis in the untreated group. The treated group delivered infants with higher birth-weight centile than did the untreated control group.

CONCLUSIONS

The combined therapeutic approach of NO donor administration and plasma volume expansion in FGR apparently improves significantly maternal hemodynamic indices. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

The Influence of HES on the Filtration Properties of Capillary Membrane Plasmaseparation

Plasmaseparation is a treatment under discussion for critically ill patients, especially in sepsis and multiorgan failure. These patients receive a variety of different fluid substitutes, including hydroxyethylstarch (HES). HES is known to influence rheological properties, but nothing is known about the possible interactions between HES and the plamaseparation procedure. We used an in vitro plasmaseparation circuit with heparinized porcine blood. Before priming the system, 2 liters of blood were supplemented by adding 100 ml of either NaCl 0.9% or HES (n=6 in each group). We monitored the transmembrane (TMP) and the filtration pressure (PF) and measured free plasma hemoglobin (free Hb) and platelet counts before and after the two hours plasmaseparation procedure. The final transmembrane pressure was significantly higher with HES substitution. In the HES group we found negative filtration pressures from the very beginning with a significant further decrease toward the end of the experiments. A significant increase in free Hb and decrease in platelet counts were noted only in the HES group. Volume substitution with HES leads to impaired filtration properties and deteriorated hemocompatibility in in vitro plasmaseparation. Further studies have yet to evaluate whether or not the effects described also occur under clinical conditions.

Effect of infusion of equine plasma or 6% hydroxyethyl starch (600/0.75) solution on plasma colloid osmotic pressure in healthy horses

OBJECTIVE To compare the effects of equivalent volumes of equine plasma and 6% hydroxyethyl starch (600/0.75) solution (hetastarch) administered IV on plasma colloid osmotic pressure (pCOP) and commonly monitored clinicopathologic variables in horses. ANIMALS 6 healthy mares. PROCEDURES In a randomized, crossover study, horses were administered hetastarch or plasma (both 10 mL/kg, IV) 18 months apart. The pCOP and variables of interest were measured before (baseline), immediately after, and at intervals up to 96 or 120 hours after infusion. Prothrombin and activated partial thromboplastin times were measured before and at 2 and 8 hours after each infusion. RESULTS Prior to hetastarch and plasma infusions, mean ± SEM pCOP was 19.4 ± 0.5 mm Hg and 19.4 ± 0.8 mm Hg, respectively. In general, hetastarch and plasma infusions comparably increased pCOP from baseline for 48 hours, with maximum increases of 2.0 and 2.3 mm Hg, respectively. Mean Hct and hemoglobin, total protein, and albumin concentrations were decreased for a period of 72, 96, or 120 hours after hetastarch infusion with maximum decrements of 8.8%, 3.2 g/dL, 1.2 g/dL, and 0.6 g/dL, respectively. Plasma infusion decreased (albeit not always significantly) hemoglobin concentration and Hct for 20 and 24 hours (maximum changes of 1.5 g/dL and 6.6%, respectively) and increased total solids concentration (maximum change of 0.6 g/dL) for 48 hours. Platelet count and coagulation times were minimally affected. CONCLUSIONS AND CLINICAL RELEVANCE Overall, the hetastarch and plasma infusions comparably increased pCOP in healthy horses for up to 48 hours. Hetastarch induced greater, more persistent perturbations in clinicopathologic variables.

Emerging hepatic syndromes: pathophysiology, diagnosis and treatment

Liver cirrhosis is a major cause of morbidity and mortality worldwide, mainly due to complications of portal hypertension. In this article, we review the current understanding on the pathophysiology, the diagnostic criteria and the available therapeutic options for patients with emerging hepatic syndromes in cirrhosis, namely the hepatorenal, hepato-adrenal and hepatopulmonary syndrome. The hepatorenal syndrome is a well-recognized complication of advanced cirrhosis and is usually associated with an accelerated course to death unless liver transplantation is performed. The hepatopulmonary syndrome is often missed in the evaluation of patients with cirrhosis; however, early recognition is essential for the efficient management of individual patients. The hepato-adrenal syndrome, although not fully characterized, offers an exciting field for research and potential therapeutic interventions.

Effect of perioperative colloid and crystalloid fluid therapy on coagulation competence, haemorrhage and outcome

BACKGROUND

Haemorrhage follows surgical intervention, but also fluid substitution may affect the blood loss. Here influence of colloids and lactated Ringer's solution (LR) on coagulation competence and haemorrhage is evaluated during cystectomy.

METHODS

A meta-analysis, a prospective observational study and three randomized controlled trials were conducted - 17 patients received HES 130/0.4, 19 patients Dextran 70, 19 patients human albumin, and 54 patients LR - with blinded evaluation of blood loss and outcome while coagulation competence was evaluated by thromboelastography (TEG) and plasma coagulation analyses.

RESULTS

Administration of HES reduced TEG determined "maximal amplitude" (TEG-MA) from 64±6 to 52±7 mm associated with a 2181±1190 mL blood loss. For Dextran values were 65±7 to 49±9 mm and 2339±1471 mL, respectively, for albumin 62±6 to 59±6 mm and 1658±684 mL compared to 65±6 to 64±6 mm and 1559±976 mL with the use of LR. Furthermore, reduced TEG-MA was independently associated with the perioperative blood loss.  A straight postoperative course was seen less often after infusion of synthetic colloids versus albumin/LR (7/36 vs. 31/73), P=0.02.

CONCLUSIONS

Perioperative bleeding is related to administration of Dextran 70 followed by HES 130/0.4 whereas albumin and LR result in a similar low level of haemorrhage. Furthermore, evaluation of coagulation competence by TEG-MA appears superior to plasma coagulation analyses for predicting the perioperative blood loss and supports that haemorrhage depends not only on the surgical intervention but also on the perioperative fluid therapy of apparent consequence for outcome.

Effects of gelatine and medium molecular weight starch as priming fluid in cardiopulmonary bypass - a randomised controlled trial

Perioperative volume replacement after cardiopulmonary bypass is complicated by post-bypass systemic inflammatory process. The aim of this study was to assess the effects of using two different colloid solutions as priming fluids in cardiopulmonary bypass. The study's primary end point was to measure the amount of fluid replacement needed during and post-cardiopulmonary bypass; blood loss, change in blood profile and intraocular pressure were secondary end points, used as measures of plasma oncotic pressures. Patients undergoing coronary artery bypass grafting were recruited. Both patients and surgeons were blinded to receive either Gelofusine® or Voluven® as priming fluids. At fixed intervals during cardiopulmonary bypass, the patients had their intraocular pressures measured. Intra and postoperative fluid replacement was in the form of 4.5% human albumin and the amount was recorded for each subject. The result did not show any significant differences in the amount of fluid needed to be replaced, in blood loss or in blood profile between the two groups. However, it showed an increase in intraocular pressure in both groups once cardiopulmonary bypass commenced. The average intraocular pressure was higher in the Gelofusine ® group compared to the Voluven® group. The significant increase in intraocular pressure measurements in the Gelofusine® group compared to the Voluven® group support the hypothesis that Voluven maintains the plasma oncotic pressure better and reduces fluid shift. Perfusion (2007) 22, 57—62.

Hydroxyethyl Starch Inhibits Intestinal Production of Cytokines and Activation of Transcription Factors in Endotoxaemic Rats

We studied the effect of hydroxyethyl starch (HES) on intestinal production of cytokines and activation of transcription factors in sepsis. Septic rats, induced by intraperitoneal lipopolysaccharide (LPS) (5 mg/kg), were treated with intravenous HES (16 ml/kg) or saline (64 ml/kg). Rat ileal tissues were collected at 2 h, 3 h or 6 h after LPS challenge. Levels of tumour necrosis factor alpha (TNF-α), interleukin (IL) 1β, IL-6, IL-8 and IL-10, cytokine mRNAs, activities of nuclear factor kappa-B (NF-κB) and activator protein-1 (AP-1), and the number of ileal myeloperoxidase (MPO)-positive cells were determined for each group. HES significantly reduced the LPS-induced increase in intestinal levels of TNF-α, IL-1β, IL-6, IL-8 and their corresponding mRNAs. HES also decreased the number of MPO-positive cells induced by LPS and inhibited activation of NF-κB and AP-1. The results suggest that in sepsis, HES may down-regulate intestinal pro-inflammatory cytokine production via suppression of NF-κB and AP-1 activation.

Characterization and physiological effect of tapioca maltodextrin colloid plasma expander in hemorrhagic shock and resuscitation model

Plasma expanders (PEs) are administered fluids to replace blood volume when massive blood loss has occured. Maltodextrin from tapioca starch was selected as a study candidate to prepare a colloid PE due to an uncomplicated production process. The formulations of mixture between tapioca maltodextrin and 0.9 % sodium chloride solution were prepared and then characterized. This was to investigate the effects of a dextrose equivalent (DE) and the concentration on the physical properties. Storage stability of each formulation was also determined and compared with clinically used PE [6 % hydroxyethyl starch (HES), 130/0.4]. The effects on the circulatory system in hamsters with hemorrhagic shock and resuscitation using prepared PE were also investigated. The results showed that low DE value led to high retrogradation, turbidity and viscosity but low colloid osmotic pressure and poor solubility. Among the prepared solutions, tapioca maltodextrin with DE6 at 10 % w/v concentration had comparable properties with 6 % HES 130/0.4. Animals resuscitated with 10 % DE6 PE had improved mean arterial blood pressure similar to those resuscitated with 6 % HES 130/0.4. However, several parameters in animals resuscitated with 10 % DE6 PE were lower than those resuscitated with 6 % HES 130/0.4, i.e., heart rate, functional capillary density. Therefore, if using tapioca maltodextrin for PE, some properties have to be considered and efficiently optimized.

Effects of intraosseous and intravenous administration of Hextend® on time of administration and hemodynamics in a Swine model

INTRODUCTION

The military recommends that a 500 mL bolus of Hextend® be administered via an intravenous (IV) 18-gauge needle or via an intraosseous (IO) needle for patients in hypovolemic shock.

PURPOSES

The purposes of this study were to compare the time of administration of Hextend and the hemodynamics of IV and IO routes in a Class II hemorrhage swine model.

METHODS

This was an experimental study using 27 swine. After 30% of their blood volume was exsanguinated, 500 mL of Hextend was administered IV or IO, but not to the control group. Hemodynamic data were collected every 2 minutes until administration was complete.

RESULTS

Time for administration was not significant (p=.78). No significant differences existed between the IO and IV groups relative to hemodynamics (p>.05), but both were significantly different than the control group (p<.05).

CONCLUSIONS

The IO route is an effective method of administering Hextend.

Effects of perfluorocarbon emulsion in rheology

AIM

To study effects of a perfluorocarbon emulsion on plasma and whole human blood viscosity in the presence of albumin or modified fluid gelatin.

MATERIAL AND METHODS

We investigated the effects of several PFC concentrations on plasma and whole blood viscosity in the presence of human albumin solution (HAS) or modified fluid gelatine (MFG; Gelofusine) to obtain three PFC emulsion concentrations (4, 8 and 15 g/dL). Three hematocrit levels (Hct) were investigated: 30, 20 and 13%, corresponding to different clinical situations. Plasma and whole blood viscosity was measured at 37 degrees C, using a Couette viscometer for shear rates ranging from 0.2 to128 s(-1).

RESULTS AND DISCUSSION

All PFC concentrations increased plasma and whole blood viscosity for the same Hct. Viscosity values similar to physiological ones were observed at Hct 13%, with MFG - PFC 4, 8 g/dL and HAS - PFC 15 g/dL; at Hct 20%, with MFG - PFC 4g/dL and HAS - PFC 15 g/dL; at Hct 30%, and HAS - PFC 4, 8 g/dL.

CONCLUSIONS

We conclude that this PFC emulsion increases plasma and blood viscosity and that among the three studied volume expanders, the interaction with MFG can result in viscosity values above the physiological one even at low Hct values. Our results suggest that such increased blood viscosity could decrease skeletal muscle oxygen pressure.

[Efficiency of hydroxyethyl starch use for arterial hypotension and shock in early postoperative period]

It is common knowledge that arterial hypotension is a one of most prevalent pathology of early neonatal period and it causes severe neurological complications. Purpose of the prospective randomized open study was to assess the efficacy of HES 130/0.4 (6% Voluven) as a start medicine for arterial hypotension in early neonatal period in comparison with normal saline solution (0.9% NaCl).

MATERIALS AND METHODS

the study was held from January 2010 to September 2011. Newborns of the ICU with arterial hypotension on the first day of life were included into the study. Acute haemorrhage was an exclusion criterion. Routine monitoring of arterial pressure, heart rate and diuresis was carried out in all newborns. pH, pCO2, pO2 blood glucose, lactate and BE levels were measured before and after the treatment. Echocardiography, examination of regional blood flow in anterior cerebral artery, renal artery and mesenteric artery was held HES 130/0.4 (6% Voluven) and saline solution (0.9% NaCl) were used Parameters of haemostasis, biochemical and haematological analysis monitored after the solutions use. Time of arterial pressure normalization and duration of the treatment positive effect were recorded Episodes of hypotension, amount of cardiotonics per day and per 7 days and duration of cardiotonics administration were recorded as well.

RESULTS

6% Voluven infusion both to 0.9% NaCl infusion normalizes the regional circulation. Furthermore it increases the blood pH and diuresis. Lactate level normalization occurred only after 6% Voluven infusion. There was not change of serum sodium level. Liver enzymes, C-protein, prothrombin index were same in both groups of patients. 6% Voluven use in newborns with extremely low birth weight was accompanied with increasing of creatinine level, prolongation of activated partial thromboplastin time and increasing of intraventricular hemorrhage rate. Newborns with weight over 1000 gram did not have these complications. Voluven advantage in comparison with saline solution is a decreasing of cardiotonics administration in patients with weight over 1000 gram.

CONCLUSIONS

6% Voluven is more effective than 0.9% NaCl for increasing of cardiac output, myocardial contractile ability and diuresis, normalization of liquid balance and lactate level, decreasing of cardiotonics amount. 6% Voluven can be recommended for arterial hypotension treatment in newborns with weight over 1000 gram both to normal saline solution especially in case of shock.

Hydroxyethyl starch (HES) versus other fluid therapies: effects on kidney function

BACKGROUND

Hydroxyethyl starches (HES) are synthetic colloids commonly used for fluid resuscitation to replace intravascular volume, yet they have been increasingly associated with adverse effects on kidney function. This is an update of a Cochrane review first published in 2010.

OBJECTIVES

To examine the effects of HES on kidney function compared to other fluid resuscitation therapies in different patient populations.

SEARCH METHODS

We searched the Cochrane Renal Group's specialised register, the Cochrane Central Register of Controlled Trials (CENTRAL, in The Cochrane Library), MEDLINE, EMBASE, MetaRegister and reference lists of articles. The most recent search was completed on November 19, 2012.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs in which HES was compared to an alternate fluid therapy for the prevention or treatment of effective intravascular volume depletion. Primary outcomes were renal replacement therapy (RRT), author-defined kidney failure and acute kidney injury (AKI) as defined by the RIFLE criteria.

DATA COLLECTION AND ANALYSIS

Screening, selection, data extraction and quality assessments for each retrieved article were carried out by two authors using standardised forms. All outcomes were analysed using relative risk (RR) and 95% confidence intervals (95% CI). Authors were contacted when published data were incomplete. Preplanned sensitivity and subgroup analyses were performed after data were analysed with a random-effects model.

MAIN RESULTS

This review included 42 studies (11,399 patients) including 19 studies from the original review (2010), as well as 23 new studies. Fifteen studies were excluded from the original review (nine retracted from publication due to concerns about integrity of data and six lacking individual patient creatinine data for the calculation of RIFLE criteria). Overall, there was a significant increase in the need for RRT in the HES treated individuals compared to individuals treated with other fluid therapies (RR 1.31, 95% CI 1.16 to 1.49; 19 studies, 9857 patients) and the number with author-defined kidney failure (RR 1.59, 95% CI 1.26 to 2.00; 15 studies, 1361 patients). The RR of AKI based on RIFLE-F (failure) criteria also showed an increased risk of AKI in individuals treated with HES products (RR 1.14, 95% CI 1.01 to 1.30; 15 studies, 8402 participants). The risk of meeting urine output and creatinine based RIFLE-R (risk) criteria for AKI was in contrast in favour of HES therapies (RR 0.95, 95% CI 0.91 to 0.99; 20 studies, 8769 patients). However, when RIFLE-R urine output based outcomes were excluded as per study protocol, the direction of AKI risk again favoured the other fluid type, with a non-significant RR of AKI in HES treated patients (RR 1.05, 95% CI 0.97 to 1.14; 8445 patients). A more robust effect was seen for the RIFLE-I (injury) outcome, with a RR of AKI of 1.22 (95% CI 1.08 to 1.37; 8338 patients). No differences between subgroups for the RRT and RIFLE-F based outcomes were seen between sepsis versus non-sepsis patients, high molecular weight (MW) and degree of substitution (DS) versus low MW and DS (≥ 200 kDa and > 0.4 DS versus 130 kDa and 0.4 DS) HES solutions, or high versus low dose treatments (i.e. ≥ 2 L versus < 2 L). There were differences identified between sepsis versus non-sepsis subgroups for the RIFLE-R and RIFLE-I based outcomes only, which may reflect the differing renal response to fluid resuscitation in pre-renal versus sepsis-associated AKI. Overall, methodological quality of the studies was good.

AUTHORS' CONCLUSIONS

The current evidence suggests that all HES products increase the risk in AKI and RRT in all patient populations and a safe volume of any HES solution has yet to be determined. In most clinical situations it is likely that these risks outweigh any benefits, and alternate volume replacement therapies should be used in place of HES products.

[Oxidised dextrans influence on reactive oxygen species generation by murine peritoneal exudate phagocytic cells]

The effects of oxidized dextrans of different molecular weight on reactive oxygen species production and transmembrane mitochondrial potential of macrophages and neutrophils have been studied in vivo and in vitro. Oxidised dextrans demonstrated moderate direct antioxidant ability but induced intracellular oxidative stress through the increase of oxygen radical generation. This effect of the investigated compounds amplifies the cytotoxic and bactericidal potential of phagocytes and can influence isoniazid metabolism, thus increasing its efficiency in therapy of infectious diseases.

[HES 130/0,4/9:1 effect on intracranial pressure, cerebral blood flow, oxygenation and cerebral vasospasm]

The paper contains results of clinical investigation of influence of intravenous infusion of 6% Hydroxyethyl starch 130/0.4/9:1 (Voluven, Fresenius Kabi) on cerebral blood flow, cerebral metabolism and ICP in 7 patients with cerebral angiospasm after subarachnoid hemorrhage. It's shown that such infusion in patients with cerebral vasospasm doesn't lead to ICP elevation but can cause regional volumetric blood flow rising and improving of cerebral metabolism.

Hydroxyethylstarch in cryopreservation - mechanisms, benefits and problems

As the progress of regenerative medicine places ever greater attention on cryopreservation of (stem) cells, tried and tested cryopreservation solutions deserve a second look. This article discusses the use of hydroxyethyl starch (HES) as a cryoprotectant. Charting carefully the recorded uses of HES as a cryoprotectant, in parallel to its further clinical use, indicates that some HES subtypes are a useful supplement to dimethysulfoxide (DMSO) in cryopreservation. However, we suggest that the most common admixture ratio of HES and DMSO in cryoprotectant solutions has been established by historical happenstance and requires further investigation and optimization.

Influence of hydroxyethyl starch (HES) 130/0.4 on hemostasis as measured by viscoelastic device analysis: a systematic review

PURPOSE

Hydroxyethyl starch solutions (HES) are plasma volume expanders which affect hemostasis. Newer HES 130/0.4 is said to be safer. Reevaluation of published evidence is necessary after the recent retraction of studies.

METHODS

Systematic review of studies assessing HES 130/0.4 effects on hemostasis by thrombelastography (TEG, ROTEM) or Sonoclot (SCR) in comparison with crystalloid or albumin control fluids was performed. Only studies which provided statistical comparisons between study fluids were analyzed. Studies were divided into in vitro or in vivo hemodilution studies. We assessed study quality, HES effects which differed significantly from controls, values outside normal range, degree of hemodilution, and cumulative HES dose.

RESULTS

Seventeen in vitro and seven in vivo hemodilution studies were analyzed. Four studies reported quality control measures. Nineteen studies (all 15 ROTEM studies, 3 of 5 in vitro TEG, and 1 of 2 SCR studies) showed a significant hypocoagulatory effect of HES 130/0.4 on clot formation, while clotting time was not uniformly affected. Three in vivo TEG studies with low HES doses or cancer patients found mixed or nonsignificant results. In studies which provided normal ranges (n = 9), more values were outside normal ranges in the HES than in the control groups (87/122 vs. 58/122, p < 0.001). Dose effects were apparent in the in vitro studies, which investigated higher dilutions up to 80%. In vivo studies were fewer and did not investigate doses >40 ml/kg.

CONCLUSIONS

HES 130/0.4 administration results in a weaker and smaller clot. Until results from well-designed clinical trials are available, safer fluids should be chosen for patients with impaired coagulation.

Effects on cardiac function of a novel low viscosity plasma expander based on polyethylene glycol conjugated albumin

BACKGROUND

Plasma expanders have become increasingly advantageous when compared to blood transfusion, due to their long shelf-life and cost-effectiveness. A new generation of plasma expander based on polyethylene glycol (PEG) conjugated to human serum albumin (PEG-HSA) has shown positive microvascular effects during extreme hemodilution and fluid resuscitation from severe hemorrhagic shock. PEG conjugation increases uniformly albumin molecular weight (MW) and colloidal osmotic pressure, with minor effects on viscosity.

METHODS

This study was designed to test the hypothesis that PEG-HSA improves and maintains cardiac function during anemic condition, independently of its lower viscosity, compared to plasma expanders with higher viscosity. To accomplish this objective, we compared PEG-HSA to colloids of different MWs and viscosities, dextran 70 kDa (moderate viscosity plasma expander, MVPE) and dextran 2000 kDa (high viscosity plasma expander, HVPE). Cardiac function was analyzed using indices derived from left ventricular pressure volume, and were assessed using a miniaturized conductance catheter, in two experimental models: 1) hemodilution and 2) resuscitation from hemorrhagic shock.

RESULTS

After hemodilution, PEG-HSA increased cardiac output compared to MVPE through the entire observation period, and HVPE increased stroke work compared to MVPE. After resuscitation, PEG-HSA increased stroke work compared to HVPE through the entire observation period. In both experimental protocols, cardiac functional changes induced by PEG-HSA were sustained over the observation time.

CONCLUSION

PEG-HSA, a low viscosity plasma expander, had beneficial effects on cardiac function when compared to conventional colloidal plasma expanders with higher viscosities. Maintenance of homeostasis during hemodilution and resuscitation from hemorrhagic shock using PEG-HSA will lead to a significant decrease of the use of blood, thus alleviating in part, forecasted blood shortages, and significantly reducing morbidity and mortality associated with the use of blood in transfusion medicine.

Hydroxyethyl starches and dextran during hip replacement surgery: effects on blood volume and coagulation

BACKGROUND

Colloid fluids influence the coagulation system by diluting the plasma and, potentially, by exerting other effects that are unique for each fluid product. We hypothesised that changes in the coagulation measured at the end of surgery would be mainly governed by differences in half-life between the colloid fluids.

METHODS

Eighty-four patients were randomised to receive one of four colloids: HES 130/0.42/6:1 (Venofundin(®)), 130/0.4/9:1 (Voluven(®)), 200/0.5/5:1 (Haes-steril(®)) and 6% dextran 70 (Macrodex(®)). Blood samples were taken just before and after a preoperative 500 ml bolus, and also after subsequent elective hip replacement surgery. Volume expansion was estimated from the blood dilution and coagulation assessed by ROTEM, activated partial thromboplastin time, prothrombin international normalised ratio (PT-INR), D-dimer and thrombin-antithrombin complex (TAT).

RESULTS

The blood volume expansion amounted to approximately 600 ml for all four colloids directly after infusion. Voluven(®) and Haes-steril(®) prolonged the aPT time and Venofundin(®) increased TAT. Although all colloids increased PT-INR and D-dimer, the ROTEM analyses showed that they consistently shortened the clotting time and weakened the clot strength. These effects were mainly unchanged after surgery, during which the haemorrhage averaged 500-600 ml. Macrodex(®) produced a stronger volume support at the end of the surgery (91% of infused volume; P<0.001) than the three starch solutions (42-60%).

CONCLUSIONS

All tested colloid fluids induced a mild hypercoagulable state with faster clotting, but with weaker clot strength. The additive influence of surgery was relatively small, and postoperative changes in coagulation were mainly due to differences in the half-life of each colloid.

Should albumin be used in all patients with spontaneous bacterial peritonitis?

Patients with cirrhosis who develop spontaneous bacterial peritonitis (SBP) have been reported to experience a high incidence of renal impairment and mortality. Renal dysfunction is possibly related to altered systemic hemodynamics that leads to decreased effective arterial blood volume. Albumin, a plasma volume expander, has been investigated to determine whether it plays a role in patients with SBP. The current literature suggests that albumin can reduce renal impairment and mortality in high-risk SBP patients, defined as patients with a serum bilirubin level of greater than 68.4 μmol⁄L, a blood urea nitrogen level of greater than 10.7 mmol⁄L or a serum creatinine level greater than 88.4 μmol⁄L. The rationale for albumin and other volume expanders in SBP is discussed, accompanied by a review of the current literature.

Maize- or potato-derived hydroxyethyl starches: is there any thromboelastometric difference?

BACKGROUND

Hydroxyethyl starches (HES) could differ with regard to the origin, and the influence on the coagulation of the raw material is unknown. This study compared the effects of a new potato-derived HES with a maize-derived HES and two crystalloid solutions.

METHODS

Whole blood from 10 healthy individuals was diluted by 20% and 40% using either non-balanced potato-derived HES 130/0.42/6:1, non-balanced maize-derived HES 130/0.4/9:1, isotonic saline or Ringer's lactate solution. Samples were analysed by thromboelastometry ROTEM(®) : Coagulation was initiated by acid ellagic [intrinsic thromboelastometry (INTEM)] or tissue factor (extrinsic thromboelastometry) with and without cytochalasin to determine the functional component of fibrinogen [cytochalasin-d-modified thromboelastometry (FIBTEM)]. Platelet count and fibrinogen activity were measured.

RESULTS

No effect of raw material was found as no difference was detected among the HES solutions. Whatever the solution, progressive haemodilution impaired haemostasis in a dose-dependant manner: For INTEM, the clot formation time was increased up to 308% and the maximum clot firmness (MCF) was decreased down to 49%. As dilution increased, initiation of coagulation was also impaired. Thromboelastometric alterations were more severe with HES than with crystalloids, especially regarding fibrin polymerization explorations: MCF of FIBTEM was considerably reduced from 12[10-14] to 2[2-3] mm (P<0.05). Fibrinogen activity and platelet count were reduced by dilution in a dose-dependant manner and decreased similarly in all groups.

CONCLUSION

Maize- and potato-derived HES have similar effects on coagulation. Both the starch preparations tested lead to more severe haemostatic defects than crystalloids, and impairment of fibrin polymerization appears to be a leading determinant of this coagulopathy.

[Comparative evaluation of the hemodynamic effect of 6% hydroxyethyl starch 130/0.42 solution versus 4% modified liquid gelatin solution in cardiosurgical patients]

The study included 20 patients who underwent a 6% HES 130/0.42 (venofundin, B-Braun) infusion test. A 4% MLG (gelofusine, B-Braun) infusion test was carried out in 16 patients. The baseline hemodynamic parameters did not differ before infusion of the compared solutions. In the HES 130 group, the mean cardiac index (CI) increase of 23% was observed in 9 cases; its reduction was seen in 7 cases. In the MLG group, the mean CI increase of 26% was noted in 14 patients and its decrease was in 10. With increased CI in response to the venofundin test infusion, there were statistically significant increases in central blood volume (CBV) by 14.6%, global end-diastolic volume (GEDV) by 13%, right atrial pressure (RAP) by 50%, and pulmonary artery wedge pressure (PAWP) by 35.5%. In the increased CI group, gelofusine caused statistically significant increases in CBV by 19%, GEDV by 7%, RAP by 33%, and PAWP by 29%. When CI was decreased in the use of MLG, there were statistically significant increases in CBV by 20%, GEDV by 17%, RAP by 49%, and PAWP by 20.5%. HES 130/0.4 resulted in increases in CBV by 18%, GEDV by 16.6%, RAP by 80%, and PAWP by 43%. 6% HES 130/0.42 and 4% MLG in doses of 500 ml had a similar hemodynamic effect in the infusion test during 30 min. Volume load with the test colloid solutions allows the functional reserves of the cardiovascular system to be estimated in cardiosurgical patients. Inotropic drugs are indicated for patients with lower cardiac output and infusion therapy is performed in those with considerably increased CI.

[Advantages of application of hydroxyethylstarch of the III generation during the operations with epidural anesthesia]

Infusion of 1000 ml of 6% hydroxyethylstarch (HES) of the third generation 130/0.42 or crystalloid solutions was conducted to patients before performance of operation on abdominal cavity organs using epidural anesthesia. While HES application the average arterial pressure after induction into anesthesia was less pronounced and concentration of C-reactive protein on the third postoperative day was lesser. It is concluded, that HES 130/0.42 secures the hemodynamic indices stability and reduction of systemic inflammatory reaction severity in the patients and do not influence hemostasis and renal function.

Effect of TachoSil in a coagulopathic pig model with blunt liver injuries

OBJECTIVE

In this study, we investigated the efficacy of a fibrinogen/thrombin-coated collagen patch (TachoSil) to terminate severe bleeding in a coagulopathic pig model with blunt liver injury.

METHODS

Following surgical preparation, which included splenectomy and cystotomy, coagulopathy was induced by exchanging 80% of the animal's blood volume with hydroxyethylstarch 130/0.4 and lactated Ringer's solution. Subsequently, a grade III liver injury was induced by a force of 238 ± 19 Newton and free bleeding was allowed for 30 s. Animals were randomly assigned to receive either a placebo patch (cotton patch) (control group, n = 7) or a fibrinogen/thrombin patch (FT patch group, n = 7), which was positioned 30 s after injury on the inflicted area. Coagulation parameters, hemodynamic variables, as well as treatment were monitored for 2 h post-injury and patch placement. Histology was obtained to evaluate the equality of liver injury and to show the morphology of the FT patch.

RESULTS

Hemostasis after hemodilution was severely impaired. Blood loss after trauma was significantly diminished in the FT patch group (419 mL ± 90 mL) compared with the control group (1775 mL ± 358 mL) (P < 0.001). All animals treated with the FT patch survived, whereas 100% of the control group died before reaching the end of the observation period (P < 0.001). Gross sectioning and histology showed an equal degree of injury with a tight adherence of the FT patch.

CONCLUSION

TachoSil under severe coagulopathy effectively controlled bleeding and successfully prevented hemorrhagic death.

Hydroxyethyl starch 130/0.4 attenuates early hepatic damage in ischemia/reperfusion injury

PURPOSE

Ischemia/reperfusion injury (IRI) remains a clinical challenge. We tested the hypothesis that fluid therapy using hydroxyethyl starch (HES) 130/0.4 during the early phase of IRI in rat liver decreases markers of hepatic injury.

METHODS

We induced liver IRI in three groups of rats anesthetized with ketamine and chlorpromazine by means of 60 min of segmental hepatic ischemia followed by 120 min of reperfusion. At the onset of reperfusion, Group 1 (IRI + HES; n = 12) was given 13 mL.kg(-1) of HES; Group 2 (IRI + HS; n = 12) received the same volume of 7.5% saline (HS), and Group 3 (IRI-only; n = 12) received no fluid. Three other groups of 12 animals each were sham-operated and received the same fluid as the test groups. We euthanized the animals after three hours, drew blood for alanine aminotransferase (ALT) quantification, and took ischemic liver samples for histomorphological study.

RESULTS

Serum ALT activity was greater in all of the IRI groups than in the sham-operated animals. The ALT activity was 1,081 +/- 575 IU.L(-1) in IRI + HES Group 1; 2,363 +/- 1,839 IU.L(-1) in IRI + HS Group 2; and 2,866 +/- 2,491 IU.L(-1) in IRI-only Group 3. There was a statistically significant difference between the IRI + HES and the IRI-only groups (P = 0.001), but not between the IRI + HS and the IRI-only groups (P > 0.05). Likewise, histological scores were greater in all IRI groups compared with the sham-operated animals. Scores were higher in the IRI-only group (median 3.5) than in the groups receiving fluid (IRI + HES median 2; IRI + HS median 3). The difference between IRI + HES and IRI-only was statistically significant (P = 0.008) but not so between IRI + HS and IRI-only (P > 0.05).

CONCLUSIONS

Giving HES 130/0.4 attenuates rat liver IRI compared with no fluid, while giving HS does not. This suggests a role for HES in hepatoprotection associated with liver IRI.

Hydroxyethyl starch 130/0.4 exerts its anti-inflammatory effect in endotoxemic rats by inhibiting the TLR4/NF-kappaB signaling pathway

Previous studies demonstrated that hydroxyethyl starch (HES) down-regulates the inflammatory response, but the mechanism is controversial. The present study measured the effects of HES130/0.4 on plasma proinflammatory cytokines levels and the Toll-like receptor-4 (TLR4)/nuclear factor-kappa B (NF-kappaB) signaling pathway in lipopolysaccharide (LPS)-treated rats. Endotoxemia was induced in rats by injection of LPS (5 mg/kg, via tail vein) and the rats were infused with different doses of HES130/0.4 (7.5, 15, or 30 ml/kg, via jugular vein). At 2 hr after the injection of LPS, plasma and peripheral monocytes were collected to determine tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta concentrations (enzyme-linked immunosorbent assay), NF-kappaB activities (electrophoretic mobility shift assay), TLR4 mRNA expression (reverse transcription-polymerase chain reaction), and TLR4 protein levels (Western blotting). The infusion of HES130/0.4 in endotoxemic rats, especially 15 ml/kg, significantly reduced the release of plasma TNF-alpha and IL-1beta, which was consistent with the observed inhibitory effects of HES130/0.4 on NF-kappaB activation, TLR4 mRNA expression, and TLR4 protein level in monocytes. Thus, HES130/0.4 evidently exerts its anti-inflammatory effect in endotoxemic rats by inhibiting the TLR4/NF-kappaB signaling pathway, which suggests that HES130/0.4 may useful for treating early Gram-negative sepsis.

The renal effect of replacement fluids in controlled severe hemorrhagic shock: an experimental study

BACKGROUND

This experimental study examined the effects of resuscitation with Ringer's lactate (RL), 6% hydroxyethyl starch (130/0.4-HES), and the combination of RL and HES on renal function in hemorrhagic shock (HS).

METHODS

Twenty-four male New Zealand white rabbits weighing 2198-3435 g were divided at random into four groups. HS was constituted by maintaining the mean arterial blood pressure at 30 mmHg and blood lactate at >4 mM/L. Subsequently, Group 1 (control) was not resuscitated, while the study rabbits' resuscitation was initiated with RL (Group 2), HES (Group 3), or the combination of RL and HES (Group 4).

RESULTS

In all groups, the serum creatinine and blood urea nitrogen (BUN) levels were observed to be within normal limits, while the lactate dehydrogenase and alpha-1 microglobulin levels statistically significantly increased when time points were compared with beginning values (p<0.05). Furthermore, cystatin-C levels were observed to be increased after the HS (p<0.05), but returned to the normal level after resuscitation in all the study groups. Interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha levels were increased in all the rabbits after HS (p<0.05), and there were no significant differences among the study groups after resuscitation (p>0.05). There were no differences in the histological imaging between the groups (p>0.05).

CONCLUSION

The 6% HES (130/0.4) did not have any harmful effects on the kidney when it was used alone or in combination with crystalloid for resuscitation of HS in rabbits.

Comparison of Treatment Modalities for Hemorrhagic Shock

Allogeneic blood resuscitation is the treatment of choice for hemorrhagic shock. When blood is unavailable, plasma expanders, including crystalloids, colloids, and blood substitutes, may be used. Another treatment modality is vasopressin, a vasoconstrictor administered to redistribute blood flow, increase venous return, and maintain adequate cardiac output. While much information exists on systemic function and oxygenation characteristics following treatment with these resuscitants, data on their effects on the microcirculation and correlation of real-time microvascular changes with changes in systemic function and oxygenation in the same animal are lacking. In this study, real-time microvascular changes during hemorrhagic shock treatment were correlated with systemic function and oxygenation changes in a canine hemorrhagic shock model (50-55% total blood loss with a MAP of 45-50 mmHg as a clinical criterion). Following splenectomy and hemorrhage, the dogs were assigned to five resuscitation groups: autologous/shed blood, hemoglobin-based oxygen carrier/Oxyglobin, crystalloid/saline, colloid/Hespan (6% hetastarch), and vasopressin. Systemic function and oxygenation changes were continuously monitored and periodically measured (during various phases of the study) using standard operating room protocols. Computer-assisted intravital video-microscopy was used to objectively analyze and quantify real-time microvascular changes (diameter, red-cell velocity) in the conjunctival microcirculation. Measurements were made during pre-hemorrhagic (baseline), post-hemorrhagic (pre-resuscitation), and post-resuscitation phases of the study. Pre-hemorrhagic microvascular variables were similar in all dogs (venular diameter = 42+/-4 microm, red-cell velocity = 0.55+/-0.5 mm/sec). All dogs showed significant (P < 0.05) post-hemorrhagic microvascular changes: approximately 20% decrease in venular diameter and approximately 30% increase in red-cell velocity, indicative of sympathetic effects arising from substantial blood loss. Microvascular changes correlated with post-hemorrhagic systemic function and oxygenation changes. All resuscitation modalities except vasopressin restored microvascular and systemic function changes close to pre-hemorrhagic values. However, only autologous blood restored oxygenation changes to pre-hemorrhagic levels. Vasopressin treatment resulted in further decreases in venular diameter (approximately 50%) as well as red-cell velocity (approximately 70%) without improving cardiac output. Our results suggested that volume replenishment - not oxygen-carrying capability - played an important role in pre-hospital/en route treatment for hemorrhagic shock. Vasopressin treatment resulted in inadvertent detrimental outcome without the intended benefit.

Increased Sympathetic Activity Present in Early Hypertensive Pregnancy is Not Lowered by Plasma Volume Expansion

OBJECTIVE

To evaluate whether sympathetic activity is increased in early-onset hypertensive pregnancy and whether this can be influenced by management with plasma volume expansion.

METHODS

The study group consisted of 74 subjects, of which 37 had early-onset hypertensive disorders of pregnancy (preeclampsia or gestational hypertension with fetal growth restriction), who were included at 24 to 34 weeks in a randomized controlled trial of management with (n = 18) or without (n = 19) plasma volume expansion. Heart rate and blood pressure variabilities, LF/HF ratio for heart rate, baroreflex sensitivity, and phase difference at low frequency (LF approximately 0.1 Hz) were calculated by spectral analysis from continuous heart rate and blood pressure recordings of the finger pulse wave (Portaprestrade mark, TNO). Measurements were performed at inclusion, after 20 to 40 hours and after 65 to 100 hours. The control group consisted of 29 women with a normal pregnancy and 8 women who had late-onset preeclampsia after 34 weeks. Controls were measured at 32 weeks. All controls had a normal blood pressures at that time.

RESULTS

LF variability of heart rate and blood pressure were significantly higher and baroreflex sensitivity was significantly lower in early-onset patients compared with normal controls. A significant trend towards higher LF variability of blood pressure and lower baroreflex sensitivity was found from normal controls to late-onset controls to early-onset patients. Parameters of sympathetic activity were not influenced by plasma volume expansion.

CONCLUSION

Sympathetic activity was increased in early-onset hypertensive pregnancy. However, this was not affected by management with plasma volume expansion, suggesting that hypovolaemia in preeclampsia is a secondary phenomenon.

[Tactics of infusion therapy in the acute period of intracranial hemorrhages]

The paper deals with the determination of infusion therapy tactics in critically ill patients with intracranial hemorrhages on the basis of invasive measurements of systemic hemodynamics. The routine hemodynamic parameters (blood and central venous pressures, heart rate) are noted to fail to assess the volemic status of the patients in full. Unlike the use of colloidal solutions, infusion therapy with physiological sodium chloride is not shown to correct systemic hemodynamics. It has been ascertained that in acute intracranial hemorrhages, infusion therapy with crystalloidal solutions leads to impaired pulmonary gas exchange and increased pulmonary extravascular fluid and the use of a combination of crystalloidal solutions and a colloidal agent in a 1:1 ratio can correct the volemic status of the patients and is not followed by lung dysfunctions.

[Effect of the combined hypertonic colloidal solution HyperHeas on hemodynamic and oxygen transport parameters, intracranial pressure, and cerebral oxygenation]

The paper gives the results of a clinical study of the effect of the new combined hypertonic colloidal and hypertonic solution HyperHaes (Frezenius-Cabi) on the parameters of systemic hemodynamics (invasive evaluation by means of a Swan-Ganz catheter), systemic oxygen transport, intracranial pressure (ICP) (lumbar spinal fluid pressure), and cerebral oximetry (INVOS 5100) in neurosurgical patients. The paradoxical effect was found as acute blood pressure lowering and elevated ICP on the beginning of solution infusion (the vasodilator effect of a distinctly hyperosmolar agent). In all other respects, HyperHaes is an ideal agent for volumetric compensation in neurosurgical patients.

[Using solutions of hydroxyethyl starch (6% HES 200/0.5 (refortan) and 6% HES 130/0.4 (voluven)) in neuroanesthesiology]

The paper provides the results of a complex experimental and clinical study of the effects of infusion solutions of hydroxyethyl starch (HES 200/0.5--Refortan and HES 130/0.4--Voluven) on hemostatic and systemic hemodynamic parameters in patients operated on for neurosurgical pathology of the brain. The HES solutions are shown to have a more pronounced volemic effect and a slightly higher hypocoagulation effect on the hemostatic system (as compared with physiological solution); the latter does not, however, achieve its clinical value with the used doses of the solutions.