Fluid therapy and outcome: a prospective observational study in 65 German intensive care units between 2010 and 2011

Colloids Yes or No? - a "Gretchen Question" Answered

Colloid solutions, both natural and synthetic, had been widely accepted as having superior volume expanding effects than crystalloids. Synthetic colloid solutions were previously considered at least as effective as natural colloids, as well as being cheaper and easily available. As a result, synthetic colloids (and HES in particular) were the preferred resuscitation fluid in many countries. In the past decade, several cascading events have called into question their efficacy and revealed their harmful effects. In 2013, the medicines authorities placed substantial restrictions on HES administration in people which has resulted in an overall decrease in their use. Whether natural colloids (such as albumin-containing solutions) should replace synthetic colloids remains inconclusive based on the current evidence. Albumin seems to be safer than synthetic colloids in people, but clear evidence of a positive effect on survival is still lacking. Furthermore, species-specific albumin is not widely available, while xenotransfusions with human serum albumin have known side effects. Veterinary data on the safety and efficacy of synthetic and natural colloids is limited to mostly retrospective evaluations or experimental studies with small numbers of patients (mainly dogs). Large, prospective, randomized, long-term outcome-oriented studies are lacking. This review focuses on advantages and disadvantages of synthetic and natural colloids in veterinary medicine. Adopting human guidelines is weighed against the particularities of our specific patient populations, including the risk-benefit ratio and lack of alternatives available in human medicine.

[Solutions for Fluid Treatment and Outcome - an Update]

Fluid therapy is one of the most frequently used medical interventions with the aim of normalizing the fluid balance. A decisive criterion for the efficiency of fluid or volume replacement is the functionality of the glycocalyx, a thin endothelial glycoprotein layer. Its solidity is an essential factor for fluid exchange and transport from the vascular system to the tissue. The recently described revised Starling principle extends the understanding considerably. From a clinical point of view, fluid treatment should aim for timely euvolemia without inducing relevant side effects. Both crystalloid and natural or synthetic colloidal solutions are available. In the case of crystalloid solutions, the so-called balanced solutions seem to be associated with fewer side effects. If the vascular barrier is intact, colloid solutions have a higher volume effect, but may have significant side effects limiting their use. At least in Europe, some synthetic colloids shall therefore no longer be used in critically ill patients. In contrast, treatment with albumin 20% in hypalbuminemic patients with cardiovascular disease leads to a reduced incidence of acute kidney injury and has also been associated with other clinical benefits. To what extent future, individualized therapeutic approaches employing colloids will influence the outcome is currently speculative.

A Prospective Observational Study of Rational Fluid Therapy in Asian Intensive Care Units: Another Puzzle Piece in Fluid Therapy

Introduction

Fluid therapy in critically ill patients, especially timing and fluid choice, is controversial. Previous randomized trials produced conflicting results. This observational study evaluated the effect of colloid use on 90-day mortality and acute kidney injury (RIFLE F) within the Rational Fluid Therapy in Asia (RaFTA) registry in intensive care units.

Materials and methods

RaFTA is a prospective, observational study in Asian intensive care unit (ICU) patients focusing on fluid therapy and related outcomes. Logistic regression was performed to identify risk factors for increased 90-day mortality and acute kidney injury (AKI).

Results

Twenty-four study centers joined the RaFTA registry and collected 3,187 patient data sets from November 2011 to September 2012. A follow-up was done 90 days after ICU admission. For 90-day mortality, significant risk factors in the overall population were sepsis at admission (OR 2.185 [1.799; 2.654], p < 0.001), cumulative fluid balance (OR 1.032 [1.018; 1.047], p < 0.001), and the use of vasopressors (OR 3.409 [2.694; 4.312], p < 0.001). The use of colloids was associated with a reduced risk of 90-day mortality (OR 0.655 [0.478; 0.900], p = 0.009). The initial colloid dose was not associated with an increased risk for AKI (OR 1.094 [0.754; 1.588], p = 0.635).

Conclusion

RaFTA adds the important finding that colloid use was not associated with increased 90-day mortality or AKI after adjustment for baseline patient condition.

Clinical significance

Early resuscitation with colloids showed potential mortality benefit in the present analysis. Elucidating these findings may be an approach for future research.

How to cite this article

Jacob M, Sahu S, Singh YP, Mehta Y, Yang K-Y, Kuo S-W, et al. A Prospective Observational Study of Rational Fluid Therapy in Asian Intensive Care Units: Another Puzzle Piece in Fluid Therapy. Indian J Crit Care Med 2020;24(11):1028–1036.

Understanding the Harms of HES: A Review of the Evidence to Date

Intravenous (IV) fluid resuscitation is one of the most common interventions in intensive care medicine. Despite clear guidelines, the choice of IV fluid is largely dependent on physician preference instead of high-quality evidence of efficacy and safety. This is particularly the case for synthetic colloids, such as hydroxyethyl starch (HES). The use of HES in critical care has been associated with increased rates of acute kidney injury (AKI), renal replacement therapy and mortality. In light of this, current guidelines and scientific and regulatory bodies do not recommend the use of HES for fluid therapy in critical illness and caution against its use in many other settings. Despite this, HES products are still debated and used. Awareness of the indications, contraindications, doses, benefits and adverse effects for IV fluids, as well as recommendations from scientific and regulatory bodies, is essential to guarantee patients' safety. Poor awareness of optimal IV fluid therapy has recently been revealed in some countries including Turkey. Therefore, we provide a review of fluids used for resuscitation, discuss safety data and adverse effects of HES, such as increased AKI and mortality, and discuss recent updates from scientific and regulatory bodies in order to raise awareness of fluid therapy. We conclude that given the lack of a clear benefit of HES in any clinical setting and the availability of safer alternatives, such as crystalloids and albumin, HES should be avoided.