The effect of tetrastarch on the endothelial glycocalyx layer in early hemorrhagic shock using fluorescence intravital microscopy: a mouse model

PURPOSE

To investigate vascular endothelial dysfunction based on glycocalyx impairment in massive hemorrhage and to evaluate fluid therapy.

METHODS

In this randomized controlled animal study, we withdrew 1.5 mL blood and administered 1.5 mL resuscitation fluid. Mice were divided into six groups according to the infusion type and administration timing: NS-NS (normal saline), NS-HES ([hydroxyethyl starch]130), HES-NS, NS-ALB (albumin), ALB-NS, and C (control) groups.

RESULTS

The glycocalyx index (GCXI) of a 40-μm artery was significantly larger in group C than in other groups (P < 0.01). Similarly, the GCXI for a 60-μm artery was significantly higher in group C than in NS-NS (P ≤ 0.05), NS-HES (P ≤ 0.01), and NS-ALB groups (P ≤ 0.05). The plasma syndecan-1 concentration, at 7.70 ± 5.71 ng/mL, was significantly lower in group C than in group NS-NS (P ≤ 0.01). The tetramethylrhodamine-labeled dextran (TMR-DEX40) fluorescence intensity in ALB-NS and HES-NS groups and the fluorescein isothiocyanate-labeled hydroxyethyl starch (FITC-HES130) fluorescence intensity in NS-HES and HES-NS groups were not significantly different from those of group C at any time point. FITC-HES130 was localized on the inner vessel wall in groups without HES130 infusion but uniformly distributed in HES130-treated groups in intravital microscopy. FITC-FITC-HES130 was localized remarkably in the inner vessel walls in group HES-NS in electron microscopy.

CONCLUSIONS

In an acute massive hemorrhage mouse model, initial fluid resuscitation therapy with saline administration impaired glycocalyx and increased vascular permeability. Prior colloid-fluid administration prevented the progression of glycocalyx damage and improve prognosis. Prior HES130 administration may protect endothelial cell function.

Fluid resuscitation after severe trauma injury : U-shaped associations between tetrastarch dose and survival time or frequency of acute kidney failure

BACKGROUND

Using tetrastarch for fluid resuscitation after a severe trauma injury may increase risks of death and acute kidney injury. The importance of tetrastarch dose, however, is unknown.

METHODS

A retrospective observational study was performed in two trauma centres using data on type and amount of fluids (balanced crystalloids or tetrastarch) used for pre- and acute in-hospital shock management. We evaluate independent associations between the relative and absolute volumes of tetrastarch and 90-day survival time or the frequency of severe acute kidney failure (AKF).

RESULTS

We studied 271 patients who had sustained a severe blunt trauma injury (average predicted mortality according to the Revised Injury Severity Classification Score (RISC) 15.1 ± 1.4% [mean, standard deviation]), and who had required more than 2 days of intensive care therapy. In all, 75.3% of patients had received tetrastarch with a crystalloid/colloid ratio of 2.93 ± 2.60. The 90-day mortality was 11.1%, and 7.8% of the patients developed severe AKF. After adjusting for confounders, we found a U-shaped, nonlinear association between absolute or relative volumes of tetrastarch and survival time (p = 0.003 and 0.025, respectively). Optimal relative volumes of tetrastarch approximately ranged from 20 to 30% of total fluids. Giving less than about 1000 ml, or more than about 2000 ml tetrastarch was significantly associated with an increased risk of developing severe AKF (p = 0.023).

CONCLUSIONS

There was a complex U‑shaped association between the tetrastarch dose and morbidity/mortality of patients after a severe trauma injury. The optimal crystalloid/tetrastarch ratio for acute shock management appears to range from about 2.5 to 4.0.

Effect of synthetic colloid administration on coagulation in healthy dogs and dogs with systemic inflammation

Background

Synthetic colloids are often used during fluid resuscitation and affect coagulation.

Objective

To compare the effects of an isotonic crystalloid and synthetic colloid on coagulation in healthy dogs and dogs with systemic inflammation.

Animals

Sixteen adult purpose‐bred Beagles.

Methods

Randomized, placebo‐controlled, blinded study. Dogs were randomized into one of two groups receiving fluid resuscitation with either 40 mL/kg IV 0.9% NaCl or tetrastarch after administration of lipopolysaccharide or an equal volume of placebo. After a 14‐day washout period, the study was repeated such that dogs received the opposite treatment (LPS or placebo) but the same resuscitation fluid. Blood samples were collected at 0, 1, 2, 4, and 24 hours for measurement of coagulation variables.

Results

Administration of either fluid to healthy dogs and dogs with systemic inflammation resulted in similar increases in prothrombin time and activated clotting time. In comparison to saline administration, tetrastarch administration resulted in significantly decreased R (P = .017) in healthy dogs, as well as significantly increased activated partial thromboplastin time (P ≤ .016), CL30% (P ≤ .016), and K (P < .001) and significantly decreased platelet count (P = .019), α (P ≤ .001), MA (P < .001), and von Willebrand factor antigen (P < .001) and collagen binding activity (P ≤ .003) in both healthy dogs and dogs with systemic inflammation.

Conclusions and Clinical Importance

Tetrastarch bolus administration to dogs with systemic inflammation resulted in a transient hypocoagulability characterized by a prolonged activated partial thromboplastin time, decreased clot formation speed and clot strength, and acquired type 1 von Willebrand disease.

Are all colloids same? How to select the right colloid?

SUMMARY

The administration of intravenous fluids is one of the most common and universal interventions in medicine. Colloids are an alternative to the frequently used crystalloids, with highly variable use depending on a myriad of clinical variables. A colloid is defined as a high molecular weight (MW) substance that largely remains in the intravascular compartment, thereby generating an oncotic pressure. Colloids are considered to have a greater intravascular persistence when compared to crystalloids. All colloids, however, are clearly not the same. Differences in the physicochemical properties, pharmacokinetics and safety profile exist amongst various colloids. This review explores the different types of colloids, with their properties and usefulness as well as adverse effects. While all the available colloids are reviewed briefly (e.g., albumin, gelatin, dextran) with respect to their pharmacology, indications, advantages and disadvantages, particular emphasis is laid on the hydroxyethyl starches (HES) because of their rising prominence. It is shown that HES differ widely in their physicochemical and pharmacokinetic properties, composition, usefulness, and especially in their adverse effect profiles. The third generation HES (tetrastarches), in particular, seem to offer a unique combination of safety and efficacy. Several issues related to this are discussed in detail. This review of the available clinical data demonstrates that HES should not be regarded as one homogenous group, and data for one product should not be automatically extrapolated to another. Thus, among the synthetic colloids, the tetrastarches appear to offer the best currently available compromise between efficacy, safety profile, and cost. They also appear to be the best suited for use in the intensive care setting. Finally, balanced (rather than saline-based) HES solutions appear promising as a plasma-adapted volume replacement strategy and may further refine the ongoing quest of finding the ideal fluid therapy.