Human monocytes and keratinocytes in culture ingest hydroxyethylstarch

The protective effect of hydroxyethyl starch solution on the glycocalyx layer in an acute hemorrhage mouse model

PURPOSE

Fluid therapy focused on glycocalyx (GCX) protection in hemorrhagic shock is a current focus of research. Hydroxyethyl starch (HES) solution is commonly used for fluid resuscitation; however, its effects on the GCX remain unclear. The primary aim of this study was to explore the protective effect of HES130 in maintaining GCX thickness and reducing plasma syndecan-1 expression.

METHODS

An acute hemorrhage murine model with the dorsal skin chambers was used to measure GCX thickness and to evaluate vascular permeability. Groups of mice were treated with normal saline (NS), albumin (NS-A), HES130 (NS-V), or no exsanguination or infusion (C). We measured syndecan-1 plasma concentrations, performed blood gas analysis, and analyzed the 7-day cumulative mortality.

RESULTS

GCX thickness in NS mice was significantly reduced compared to that in group C, but no other groups showed a difference compared to group C. The plasma concentration of syndecan-1 was significantly higher in NS mice than in group C. There were no significant differences in the fluorescence intensity of dextran in the interstitial space. HES70 leakage was suppressed in NS-V mice compared to those in other groups. HES70 was localized to the inner vessel wall in C, NS, and NS-A mice, but not in group NS-V. Blood gas analysis indicated that pH and lactate showed the greatest improvements in NS-V mice. The 7-day cumulative mortality rate was the highest in group NS.

CONCLUSION

Resuscitation with HES130 protected the GCX and suppressed vascular permeability of HES70 during early stages of acute massive hemorrhage.

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.

Giving long-persistent starch as volume replacement can cause pruritus after cardiac surgery

We reviewed the prevalence and severity of pruritus in 85 patients after cardiac surgery. EloHAES, a long-lasting hydroxyethylated starch, was given to 59 of these patients. None of the patients who did not receive EloHAES developed pruritus, compared with 22% of those who did (P = 0.007). The timing of onset, duration and severity of the pruritus are similar to those found previously for other hydroxyethylated starches, and the cause of this pruritus is likely to be similar. Hydroxyethyl starch can cause long-term pruritus.

The pharmacokinetics of acetyl starch as a plasma volume expander in patients undergoing elective surgery

Acetyl starch (ACS) is a new synthetic colloid solution for plasma volume expansion and is now undergoing phase 2 clinical trials. We compared the pharmacokinetics of ACS with those of hydroxyethyl starch (HES) in 32 patients (ASA physical status I and II) undergoing elective surgery. In this randomized, double-blind trial, patients received either 15 mL/kg ACS 6% (average molecular weight [Mw] 200,000/molar substitution [MS] 0.5) or HES 6% (Mw 200,000/MS 0.5) i.v. up to a maximal dose of 1000 mL. Plasma colloid concentrations were measured by repetitive arterial blood sampling over 24.5 h. Plasma colloid concentrations were detected using a high-pressure liquid chromatography controlled enzymatic test. Standard pharmacokinetics were calculated, including initial half-life (t(1/2init)), i.e., the time required for a 50% decline of the maximal plasma colloid concentration at the end of drug infusion. Whereas HES was eliminated by second-order kinetics, ACS followed first-order characteristics. In the first hours after i.v. administration, t(1/2init) and clearances were similar in both groups. However, the terminal half-life of HES was significantly longer than that of ACS (9.29 +/- 1.43 h vs 4.37 +/- 1.06 h). After 16.5 and 24.5 h, ACS showed significantly lower plasma concentrations than HES, which indicates that the final degradation of ACS by esterases and amylase was significantly more rapid. ACS might be an alternative plasma volume expander, which avoids the accumulation of persisting macromolecules.

IMPLICATIONS

We studied the pharmacokinetics of acetyl starch, a newly developed colloid solution for plasma volume substitution, compared with hydroxyethyl starch in 32 surgical patients undergoing elective major general surgical procedures. In contrast to hydroxyethyl starch, this new agent undergoes rapid and nearly complete enzymatic degradation.

Efficacy of pentastarch in granulocyte collection by centrifugal leukapheresis

The efficacy of 6% hydroxyethyl starch (hetastarch, HS) in enhancing granulocyte harvest by centrifugal leukapheresis has been described by a simple equation which predicts the granulocyte collection efficiency (GCE) based on an intrinsic donor variable, the erythrocyte sedimentation rate (ESR): GCE(%) = 1.3 ESR (mm/hr) + 45. Ten percent low molecular weight hydroxyethyl starch (pentastarch, PS) has been reported to be as effective as HS with potentially fewer adverse donor reactions (ADR). The derivation of an analogous equation for PS under conditions previously reported for HS may quantify PS efficacy and allow comparison to HS. We prospectively measured the in vitro and the in vivo effects of PS on the donor ESR in 53 granulocyte collections from 44 donors using the model CS-3000 Plus blood cell separator (CS). We then correlated the findings with the GCE of each procedure and derived an equation which expresses GCE in terms of baseline donor ESR. The in vitro addition of PS increased the donor ESR 2.4-fold, but its administration to a donor during a collection procedure did not appreciably change the ESR. Higher baseline donor ESR was more likely to result in more efficient cell collections: GCE (%) = 0.8 ESR (mm/hr) + 20; (r = 0.37). For granulocyte harvests using the CS and PS as the sedimenting agent 1) baseline donor ESR affects granulocyte harvests, but the poor correlation does not allow an accurate prediction of GCE and cell yield from the baseline donor ESR; 2) in comparison with HS (results from a previous study), PS may be less effective in vitro and not effective in vivo in elevating ESR, and may be less effective in enhancing granulocyte harvest; and 3) the parameters (slope, y-intercept, correlation coefficient) which define the linear relationship between baseline donor ESR and GCE may serve collectively as a quantitative measure of the effectiveness of different hydroxyethyl starch agents in enhancing granulocyte harvests. These parameters may be helpful in rapidly assessing the clinical efficacy of new, potentially useful hydroxyethyl starch agents prior to initiating a randomized, controlled clinical trial.

Successful treatment of hydroxyethyl starch-induced pruritus with topical capsaicin

We report a case of recalcitrant pruritus after infusion therapy with hydroxyethyl starch (HES) for sudden deafness. The diagnosis was confirmed by detection of typical HES storage vacuoles within dermal macrophages and perineural cells. Treatment with antihistamines and antipruritic agents, UVB irradiation, and neuroleptic drugs, was ineffective. Topical capsaicin (0.05%) twice daily produced excellent symptomatic relief, without side-effects.