[Study protocol of the VISEP study. Response of the SepNet study group]

Hydroxyeyhyl starch: Controversies revisited

Hydroxyethyl starch (HES) family has been one of the cornerstones in fluid management for over four decades. Recent evidence from clinical studies and meta-analyses has raised few concerns about the safety of these fluids, especially in certain subpopulations of patients. High-quality clinical trials and meta-analyses have emphasized nephrotoxic effects, increased risk of bleeding, and a trend toward higher mortality in these patients after the use of HES solutions. Scientific evidence was derived from international guidelines, aggregated research literature, and opinion-based evidence was obtained from surveys and other activities (e.g., internet postings). On critical analysis of the current data available, it can be summarized that further large scale trials are still indicated before HES can be discarded.

[Limited applications for hydroxyethyl starch : background and alternative concepts]

BACKGROUND

Within the framework of a risk assessment procedure the Committee for Risk Assessment of Pharmacovigilance (PRAC) of the European Medicines Agency (EMA) came to the conclusion that the benefits of hydroxylethyl starch infusion solutions (HES) no longer outweighed the risks and on 14 June 2013 recommended that approval should be suspended. Until the procedure has finally been concluded, which could last several months, the Federal Institute for Drugs and Medical Products (BfArM) has recommended that HES should not be used.

AIM

The aim of this article is to present the data situation in the most objective and compact way and to ultimately give the reader the foundations in order to be able to form a personal opinion. In addition an attempt will be made to describe a concept how infusion therapy can be carried out without using hydroxyethyl starch (HES).

MATERIAL AND METHODS

The background to this decision is given based on a review of the literature and the relevance for intensive care, emergency and perioperative medicine is assessed. Furthermore, a concept of infusion therapy without hydroxyethyl starch is formulated also based on the results of current studies.

RESULTS

For infusion regimens without HES it should be noted that gelatin represents a considerable risk for anaphylactic reactions, that transfer of the new variants of Creutzfeldt-Jacob disease (bovine spongiform encephalopathy BSE) cannot fundamentally be excluded and that some evidence has been found that gelatin can cause kidney injury, probably in a similar way to HES. With respect to the cost-benefit analysis of infusion solutions, blood loss in adults of approximately 1-1.5 l can be substituted by balanced crystalloids (basic therapy 4-5 times compared to the amount of blood lost). For larger blood losses small amounts of hyperoncotic albumin solution (20 %) or alternatively 5 % albumin solution can be used. The 20 % albumin solution seems to have some advantages because it has a higher volume effect (approximately 200 %) and can be more favourable for the fluid balance than 5 % albumin solution. Blood losses greater than 2-3 l normally also require administration of blood products (e.g. fresh frozen plasma FFP and erythrocyte concentrates EC).

CONCLUSIONS

The third generation HES solutions cannot be completely replaced by other colloids and in future crystalloids will more strongly again broadly form the basis for infusion therapy. In this aspect balanced crystalloids have priority with respect to the acid-base equilibrium. The history of HES has impressively shown that infusion therapy must be adjusted on a scientifically founded basis, whether in intensive care medicine, perioperative or emergency medicine. Large prospective studies with clinically relevant endpoints are urgently needed.

Hyperglycemia increases the complicated infection and mortality rates during induction therapy in adult acute leukemia patients

OBJECTIVE

To determine the prevalence of hyperglycemia during induction therapy in adult patients with acute leukemia and its effect on complicated infections and mortality during the first 30 days of treatment.

METHODS

An analysis was performed in a retrospective cohort of 280 adult patients aged 18 to 60 years with previously untreated acute leukemia who received induction chemotherapy from January 2000 to December 2009 at the Hemocentro de Pernambuco (HEMOPE), Brazil. Hyperglycemia was defined as the finding of at least one fasting glucose measurement > 100 mg/dL observed one week prior to induction therapy until 30 days after. The association between hyperglycemia and complicated infections, mortality and complete remission was evaluated using the Chi-square or Fisher's exact tests by the Statistical Package for Social Sciences (SPSS) in the R software package version 2.9.0.

RESULTS

One hundred and eighty-eight patients (67.1%) presented hyperglycemia at some moment during induction therapy. Eighty-two patients (29.3%) developed complicated infections. Infection-related mortality during the neutropenia period was 20.7% (58 patients). Mortality from other causes during the first 30 days after induction was 2.8%. Hyperglycemia increased the risk of complicated infections (OR 3.97; 95% confidence interval: 2.08 - 7.57; p-value < 0.001) and death (OR 3.55; 95% confidence interval: 1.77-7.12; p-value < 0.001) but did not increase the risk of fungal infections or decrease the probability of achieving complete remission.

CONCLUSION

This study demonstrates an association between the presence of hyperglycemia and the development of complicated infections and death in adult patients during induction therapy for acute leukemia.

[Volume replacement in intensive care medicine]

Volume substitution represents an essential component of intensive care medicine. The amount of fluid administered, the composition and the timing of volume replacement seem to affect the morbidity and mortality of critically ill patients. Although restrictive volume strategies bear the risk of tissue hypoperfusion and tissue hypoxia in hemodynamically unstable patients liberal strategies favour the development of avoidable hypervolemia with edema and resultant organ dysfunction. However, neither strategy has shown a consistent benefit. In order to account for the heavily varying oxygen demand of critically ill patients, a goal-directed, demand-adapted volume strategy is proposed. Using this strategy, volume replacement should be aligned to the need to restore tissue perfusion and the evidence of volume responsiveness. As the efficiency of volume resuscitation for correction of tissue hypoxia is time-dependent, preload optimization should be completed in the very first hours. Whether colloids or crystalloids are more suitable for this purpose is still controversially discussed. Nevertheless, a temporally limited use of colloids during the initial stage of tissue hypoperfusion appears to represent a strategy which uses the greater volume effect during hypovolemia while minimizing the risks for adverse reactions.

Are renal adverse effects of hydroxyethyl starches merely a consequence of their incorrect use?

BACKGROUND

Clinical studies such as VISEP-study, which show a negative outcome after the administration of hydroxyethyl starch (HES), are often criticized for an "incorrect" use of HES. It is argued that HES used in these studies differed from usual practice and that recommendations for maximal dosage, duration, and creatinine values were ignored, not enough "free water" was provided and more modern HES solutions should have been used. These comments imply that renal adverse events in clinical studies are the consequence of an inappropriate use of HES. We therefore searched for evidence whether these suggested measures are beneficial.

METHODS

Narrative review; post hoc statistical analysis of epidemiologic data from a representative nationwide survey.

RESULTS

It is evident from published clinical studies that the renal risk of HES increases with cumulative dose and rising serum creatinine values, but no safe upper dose limit or creatinine threshold is known. Suggested safety measures were not able to prevent HES-induced renal failure in clinical studies. Published clinical trials with modern HES solutions are not suited to prove its assumed increased safety because of small sample sizes, low cumulative doses, short observation periods, and inadequate control fluids. Use of HES in a clinical study with negative outcomes conformed to clinical practice, indicating the generalizability of study results.

CONCLUSION

There is no evidence for the assumption that HES-associated renal impairment may be avoided by accompanying measures. Because HES use does not improve clinical outcome, the question arises whether it should be used at all in patients at risk.

Early fluid resuscitation with hyperoncotic hydroxyethyl starch 200/0.5 (10%) in severe burn injury

Introduction

Despite large experience in the management of severe burn injury, there are still controversies regarding the best type of fluid resuscitation, especially during the first 24 hours after the trauma. Therefore, our study addressed the question whether hyperoncotic hydroxyethyl starch (HES) 200/0.5 (10%) administered in combination with crystalloids within the first 24 hours after injury is as effective as 'crystalloids only' in severe burn injury patients.

Methods

30 consecutive patients were enrolled to this prospective interventional open label study and assigned either to a traditional 'crystalloids only' or to a 'HES 200/0.5 (10%)' volume resuscitation protocol. Total amount of fluid administration, complications such as pulmonary failure, abdominal compartment syndrome, sepsis, renal failure and overall mortality were assessed. Cox proportional hazard regression analysis was performed for binary outcomes and adjustment for potential confounders was done in the multivariate regression models. For continuous outcome parameters multiple linear regression analysis was used.

Results

Group differences between patients receiving crystalloids only or HES 200/0.5 (10%) were not statistically significant. However, a large effect towards increased overall mortality (adjusted hazard ratio 7.12; P = 0.16) in the HES 200/0.5 (10%) group as compared to the crystalloids only group (43.8% versus 14.3%) was present. Similarly, the incidence of renal failure was 25.0% in the HES 200/0.5 (10%) group versus 7.1% in the crystalloid only group (adjusted hazard ratio 6.16; P = 0.42).

Conclusions

This small study indicates that the application of hyperoncotic HES 200/0.5 (10%) within the first 24 hours after severe burn injury may be associated with fatal outcome and should therefore be used with caution.

Trial registration

NCT01120730.