The Influence of Two Different Hydroxyethyl Starch Solutions (6% HES 130/0.4 and 200/0.5) on Blood Viscosity

Abstract

We performed the current study to investigate the influence of 2 different hydroxyethyl starch (HES) solutions, the novel medium molecular weight HES 130/0.4 (6%) and HES 200/0.5 (6%), on plasma and whole blood viscosity in vitro and ex vivo in patients with severe head injury. For the in vitro experiments, blood was incubated with increasing concentrations (0%-50% vol/vol plasma) of either 6% HES 130/0.4 or 6% HES 200/0.5 solution. Plasma viscosity and whole blood viscosity (hematocrit [Hct] 45%) at high (94.5 s(-1)) and low (0.1 s(-1)) shear rates were determined. Both HES solutions increased plasma viscosity, but HES 130/0.4 to a lesser extent than HES 200/0.5. Whole blood viscosity was significantly less with HES 130/0.4 than with HES 200/0.5 at concentrations of 37.5% and larger. In the ex vivo study on 31 patients with severe cranio-cerebral trauma treated randomly with either HES 130/0.4 or HES 200/0.5 over several days, frozen plasma samples were thawed and plasma viscosity was determined. Blood was reconstituted with normal erythrocytes (0, Rh neg, Hct 45%) for whole blood viscosity measurements. In both groups plasma and blood viscosity tended to increase over time without statistical significance. Although the prominent effects found in vitro are not in keeping with the ex vivo data, they are likely to reflect the true clinical situation during repetitive, large-dose HES administration. We therefore conclude that HES 130/0.4 may have hemorheological advantages over conventional HES 200/0.5 when used in large quantities.

L’hydroxyéthylamidon 130/0,4 atténue les dommages hépatiques précoces causés par les lésions d’ischémie/reperfusion

“…[14][15][16][17][18][24][25][26][27][28][29] We shared the commonly held perception that both volume effect and molecule characteristics are among the most important factors in organ protection; however, the current study demonstrated that the HES molecule plays a role in hepatoprotection against reperfusion injury. The infused volume of HES solution (13 mLÁkg -1 ) adjusted to the weight of the rats was within the doses reported for volume repletion in clinical studies.…”

“…There is evidence of a better safety profile with HES 130/04 compared with the older colloids, and it is often preferred over pure crystalloid regimens because of its prolonged intravascular half-life and positive impact on blood rheology and tissue oxygenation. [24][25][26][27][28][29] Moreover, Lang et al 18 showed a significant attenuation of inflammatory markers, such as interleukins 6 and 8 and soluble Fig. 1 Alanine aminotransferase (ALT) levels in animals that were subjected to one hour of 70% warm ischemia and two hours of reperfusion and in sham-operated controls.…”

Effect of High- and Low-molecular-weight Low-substituted Hydroxyethyl Starch on Blood Coagulation during Acute Normovolemic Hemodilution in Pigs

“…However, no significant differences after hemodilution with HES 650/0.42 as compared with HES 130/0.42 have been observed by relating the decrease in hemoglobin concentration to the measured HES in vivo molecular weights ( fig. 6F) 26,27 The predominant rheologic effect of colloids consists in the reduction of whole blood viscosity proportional to the magnitude of their plasma volume expansion. 27 Plasma viscosity, however, is determined principally by the number and physical properties of dissolved macromolecules.…”

“…6F) 26,27 The predominant rheologic effect of colloids consists in the reduction of whole blood viscosity proportional to the magnitude of their plasma volume expansion. 27 Plasma viscosity, however, is determined principally by the number and physical properties of dissolved macromolecules. 27 Accordingly, progressive acute normovolemic hemodilution with HES 650/0.42 and HES 130/0.42, respectively, leads to improved rheologic conditions by demonstrating a significant decrease of whole blood viscosity (24%) as well as a strong downward trend of plasma viscosity (6%) (figs.…”

Colloid solutions: a clinical update

“…It has also been shown experimentally that pulmonary capillary leakage is prevented to a greater extent by HES than by gelatin [70]. Improvement of microcirculation [71] and decrease of plasma viscosity by HES but not by gelatin [72] may also be translated into good tissue oxygenation not seen during the administration of Ringer's lactate alone [73,74] (Fig. 2).…”