Hydroxyethyl starch: safe or not?

Effects of colloid pre-loading on thromboelastography during elective intracranial tumor surgery in pediatric patients: hydroxyethyl starch 130/0.4 versus 5% human albumin

BACKGROUND

Volume replacement therapy with colloid is still worth studying in major pediatric surgery with potential risk of bleeding. This study assessed the effects of 6% hydroxyethyl starch (HES) 130/0.4 and 5% Human Albumin (HA) on coagulation tested by thromboelastography (TEG) during elective intracranial tumor surgery in pediatric patients.

METHODS

In this randomized controlled trial, 60 patients undergoing intracranial tumor resection under general anesthesia were assigned to HES and HA groups (n = 30), and administered preloads of 20 mL · kg^-1 HES 130/0.4 and 5% HA, respectively, prior to dura opening. Primary outcomes were perioperative thromboelastography findings, and hemodynamic and hematological parameters. Blood transfusion, perioperative fluid balance, intracranial pressure, mortality, intensive care unit stay, and hospital stay were also assessed.

RESULTS

TEG parameters did not differ after preloading compared to baseline values in either group, except for a decrease in maximum amplitude immediately after infusion (HES group, 57.6 ± 6.0 mm vs. 50.9 ± 9.2 mm; HA group, 60.1 ± 7.9 mm vs. 56.6 ± 7.1 mm; p < 0.01), which was restored to preoperative levels 1 h after fluid infusion. Total perioperative fluid balance, blood loss or transfusion, intracranial pressure, and hematological and hemodynamic variables were similar between both groups (p > 0.05). Mortality, length of hospital stay, and clinical complications were similar between both groups.

CONCLUSION

These findings suggest that HES and HA might have no significant differences regarding coagulation as assessed by TEG during pediatric intracranial tumor surgery with 20 ml/kg volume pre-loading, which can maintain stable hemodynamics and may represent a new avenue for volume therapy during brain tumor resection in pediatrics.

TRIAL REGISTRATION

ChiCTR-IPR- 16009333 , retrospectively registered October 8, 2016.

Comparing the Effects of 5% Albumin and 6% Hydroxyethyl Starch 130/0.4 (Voluven) on Renal Function as Priming Solutions for Cardiopulmonary Bypass: A Randomized Double Blind Clinical Trial

Background:

The ideal strategy to prime the cardiopulmonary bypass (CPB) circuit in adult cardiac surgery is still a matter of debate.

Objectives:

In this retrospective study, we examined Albumin solution and hydroxyethyl starch (HES) for priming the CPB circuit and evaluated the differences in kidney function and bleeding and coagulation status in the two groups of patients.

Patients and Methods:

Sixty consecutive patients undergoing elective coronary artery bypass grafting were studied. Patients were excluded due to emergency surgery, history of cardiac surgery, history of receiving medication with antiplatelet agents except ASA 80 (mg/day) within the previous five days, preoperative coagulation disorder, left ventricular ejection fraction less than 50%, preoperative renal dysfunction (serum creatinine > 1.4 mg/dL), preoperative hepatic dysfunction (serum aspartate/alanine amino transferase > 60 U/l), preoperative electrolyte imbalance, known hypersensitivity to HES and chronic diuretic therapy. The patients were divided randomly into two groups of HES (n = 30) and Albumin (n = 30). Hemodynamic parameters, serum creatinine concentrations and glomerular filtration rate, PT, PTT and INR were measured. Early bleeding was measured according to the first 24-hour drainage from the tube. Hemodynamics and all laboratory measurements were performed after induction of anesthesia and at the morning of the first, second and third postoperative days in the ICU.

Results:

GFR differences were statistically lower in Albumin group in comparison with Group B at 24, 48 and 72 hours postoperation. Platelet count difference and postoperative bleeding were significantly lower in Albumin group.

Conclusions:

Administration of Albumin compared to HES in patients with a normal renal function results in a lower drop of GFR and platelet count, less bleeding and lower rise of serum creatinine.

Assessment of coagulation with 6% hydroxyethyl starch 130/0.4 in cesarean section

BACKGROUND

Third-generation hydroxyethyl starch (HES) solutions have been developed to minimize negative effects on hemostasis. In normal pregnancy, the coagulation activity increases, reaching a maximum around term. This study examined the effects of hemodilution with HES 130/0.4 (6%) on blood coagulation in parturients in vivo and in vitro.

METHODS

Forty parturients scheduled for cesarean sections were assigned randomly to receive either 500 or 1,000 ml of HES 130/0.4 (6%). Rotation thromboelastometry (ROTEM®) measurements were performed before and after administering HES 130/0.4 (6%). In addition, blood samples obtained from 20 randomly selected parturients were diluted 10% to 40% using HES 130/0.4 (6%), and ROTEM® measurements were performed before and after dilution. The changes from baseline and the effects of dilution were analyzed by ROTEM® parameters.

RESULTS

Infusions of 500 or 1,000 ml of HES 130/0.4 (6%) in the parturients altered the clot formation time, α angle, and maximal clot firmness, although all remained within normal ranges. HES 130/0.4 (6%) affected in vitro blood coagulation in parturients' blood containing 10, 20, 30, and 40% HES. The clotting time was prolonged at each dilution percentage, but remained within the normal range. Other parameters showed an impairment of the coagulation system.

CONCLUSIONS

Blood coagulation in parturients may be compromised at high dilution ratios of HES 130/0.4 (6%) to blood. Nevertheless, the infusion of 1,000 ml of HES 130/0.4 (6%) in normal parturients did not significantly affect blood coagulation.

Influence of colloid infusion on coagulation during off-pump coronary artery bypass grafting

This study was conducted to determine the influence of colloid infusion on coagulation in patients undergoing off-pump coronary artery bypass grafting (OP-CABG). Thirty patients undergoing elective OP-CABG received medium molecular weight hydroxyethyl starch group I (MMW-HES 200/0.5), low molecular weight hydroxyethyl starch group II (LMW-HES 130/0.4) or gelatin group III (GEL) in a prospective randomized trial. Blood samples were assessed for hemoglobin (Hb), activated coagulation time (ACT), prothrombin time (PT), activated partial thromboplastin time (aPPT), platelet count, fibrinogen and von Willebrand factor (vWF) at specified intervals. Total volume of the colloid infused and postoperative chest-time drainage was also measured. There was a significant decrease in Hb, platelet count, fibrinogen levels in all these groups, which did not warrant blood transfusion. After the colloid infusion, vWF decreased significantly to 67% from baseline in group I as compared to 85 and 79% in group II and group III, respectively. vWF levels remained lower than the baseline value in the first 24 hours in group I, whereas this factor level increased above the baseline values in groups II and III, 6 hours postoperatively. Postoperative chest tube drainage in 24 hours was significantly higher in group I (856 ± 131 ml) as compared to group II (550 ± 124 ml) and group III (582 ± 159 ml). LMW-HES 130/0.4 was superior to MMW-HES 200/0.5 and gelatin in patients undergoing OP-CABG, in terms of better preservation of coagulation associated with enhanced volume effect.

[Hydroxyethylstarch (HES)]

Adequate volume replacement therapy is a mainstay of managing the critically ill. The ideal kind of volume replacement in this situation still remains a challenge. In spite of an immense number of contributions to this problem there is still no definite answer. The ideal volume replacement strategy should not only aim at maintaining stable systemic hemodynamics, organ perfusion and microcirculation should be guaranteed or even improved as well. Due to its excellent efficacy, hydroxyethylstarch (HES) preparations are widely used to treat hypovolemia. The different physico-chemical properties of the available HES solutions, however, should be taken into account. Anphylactoid reactions as well as negative effects on coagulation, kidney/liver function and on the immune system are frequently used arguments against the administration of HES, but they can virtually be neglected when using modern HES preparations to correct hypovolemia. There are, however, still open questions concerning the use of HES in children, pregnant patients, patients with altered kidney function and in burn patients.

Effect of hydroxyethyl starch infusion on colloid oncotic pressure in hypoproteinemic horses

OBJECTIVE

To determine the effect of hydroxyethyl starch (HES) on colloid oncotic pressure (pi) during fluid resuscitation of hypoproteinemic horses and to evaluate the clinical usefulness of direct and indirect methods for determination of pi before and after infusion of a synthetic colloid.

DESIGN

Prospective clinical study.

ANIMALS

11 hypoproteinemic horses.

PROCEDURE

Horses received IV infusions of 8 to 10 ml of a 6% solution of HES/kg (3.6 to 4.5 ml/lb) of body weight during fluid resuscitation. Blood samples were obtained for determination of plasma measured colloid oncotic pressure (pi meas) and plasma total protein and albumin (A) concentrations. Plasma globulin concentration (G) was calculated as the difference between plasma total protein and albumin concentrations. Calculated values for colloid oncotic pressure (piA + G) were determined by use of a predictive nomogram previously developed for horses.

RESULTS

There was no significant difference between the means of pi meas and piA + G at the beginning of HES infusion. After HES infusion, the mean of pi meas was increased significantly from baseline for 6 hours. Mean plasma total protein and albumin concentrations and piA + G were decreased significantly from baseline for 24 hours. Differences between mean pi meas and piA + G after HES infusion were significant for 24 hours.

CONCLUSIONS AND CLINICAL RELEVANCE

There was good agreement between plasma pi meas and piA + G in blood samples obtained from hypoproteinemic horses immediately before infusion of HES. Use of a predictive nomogram did not, however, account for the oncotic effect of HES. Results of comparison of pi meas to piA + G after HES infusion suggest that a significant oncotic effect was maintained for 24 hours in the study horses.

Hypertonic-hyperoncotic saline differentially affects healthy and glutamate-injured primary rat hippocampal neurons and cerebral astrocytes

Hypertonic-hyperoncotic saline solutions (HHS) have been used for small-volume resuscitation and to treat intracranial hypertension and cerebral edema in neurocritical care. Little is known on the response of brain cells to direct exposure in HHS, which may occur in blood-brain barrier disruption. We studied the effects of HHS on healthy and glutamate-injured brain cells in vitro. To model a hypertonic-hyperoncotic environment, rat hippocampal neurons and cerebral astrocytes were exposed to hypertonic saline and hydroxyethyl starch (HES) added to medium for 15 minutes (final osmolarity: 350 mOsm/L in the neuronal, 373 mOsm/L in the glial medium; 2.5 mg/mL HES in both media). To simulate excitotoxicity, cells were exposed to 100 microM glutamate for 8 minutes before exposure to HHS. Cell viability was analyzed by morphology and vital dye staining; intracellular water space (WS) and glucose use were measured by scintillation spectrometry using 3-O-methyl[14C]-D-glucose and [3H]2-deoxy-D-glucose ([3H]2-DG). After 24 hours, exposure to HHS added to medium caused a 30% reduction in viability of healthy neurons (P < .05), but did not exacerbate the glutamate-induced 50% decrease in neuronal survival. One hundred percent astrocyte viability remained unchanged. The WS of astrocytes and surviving neurons was negligibly altered. Exposure to HHS added to medium caused a 35% reduction in [3H]2-DG in healthy and glutamate-injured neurons (P < .05), but did not affect [3H]2-DG in astrocytes. Our data show that HHS may potentially injure hippocampal neurons. Preserved WS values imply that live cells maintained volume regulation capabilities, indicating a lack of dehydration 24 hours after exposure to HHS. Impaired glucose use predisposes neurons to disturbed metabolism, which may influence neuronal outcome after brain injury.