# In vivo effects of balanced, low molecular 6% and 10% hydroxyethyl starch compared with crystalloid volume replacement on the coagulation system in major pancreatic surgery—a sub-analysis of a prospective double-blinded, randomized controlled trial

## TL;DR

This study compares the effects of hydroxyethyl starch solutions and crystalloids on blood clotting during major pancreatic surgery, finding temporary changes in clotting factors with HES.

## Contribution

The study provides new insights into the transient impact of low-molecular HES on coagulation during major surgery.

## Key findings

- Fibrinogen levels decreased significantly in all groups at the end of surgery, most notably in HES groups.
- MCF FIBTEM values dropped in HES groups but returned to baseline by the first postoperative day.
- No differences in blood loss or transfusion requirements were observed between groups.

## Abstract

The outcome of patients undergoing major surgery treated with HES for hemodynamic optimization is unclear. This post-hoc analysis of a randomized clinical pilot trial investigated the impact of low-molecular balanced HES solutions on the coagulation system, blood loss and transfusion requirements.

The Trial was registered: EudraCT 2008-004175-22 and ethical approval was provided by the ethics committee of Berlin. Patients were randomized into three groups receiving either a 10% HES 130/0.42 solution, a 6% HES 130/0.42 solution or a crystalloid following a goal-directed hemodynamic algorithm. Endpoints were parameters of standard and viscoelastic coagulation laboratory, blood loss and transfusion requirements at baseline, at the end of surgery (EOS) and the first postoperative day (POD 1).

Fifty-two patients were included in the analysis (HES 10% (n = 15), HES 6% (n = 17) and crystalloid (n = 20)). Fibrinogen decreased in all groups at EOS (HES 10% 338 [298;378] to 192 [163;234] mg dl-1, p<0.01, HES 6% 385 [302;442] to 174 [163;224] mg dl-1, p<0.01, crystalloids 408 [325;458] to 313 [248;370] mg dl-1, p = 0.01). MCF FIBTEM was decreased for both HES groups at EOS (HES 10%: 20.5 [16.0;24.8] to 6.5 [5.0;10.8] mm, p = <0.01; HES 6% 27.0 [18.8;35.2] to 7.0 [5.0;19.0] mm, p = <0.01). These changes did not persist on POD 1 for HES 10% (rise to 16.0 [13.0;24.0] mm, p = 0.88). Blood loss was not different in the groups nor transfusion requirements.

Our data suggest a stronger but transient effect of balanced, low-molecular HES on the coagulation system. Despite the decline of the use of artificial colloids in clinical practice, these results may help to inform clinicians who use HES solutions.