Journal of Blood Disorders & Transfusion

Abstract

Effects of High Dose Fibrinogen on in vitro Haemodilution with Different Therapeutic Fluids

Eric Lidgard, Attila Frigyesi and Ulf Schött

Background: Therapeutic fluids used in intensive care can have profound effects on coagulation, not only by dilution itself but also by other more complicated interactions. The aim of this in vitro study was to monitor the extent of dilutive coagulopathy induced by the most common therapeutic fluids and to attempt normalization of haemostasis by fibrinogen addition.

Methods: 8 patients were recruited from the intensive care unit. Native whole blood was drawn, diluted by 50% with 9 different fluids, and run through a Sonoclot Analyzer. This was then repeated with high dose fibrinogen (corresponding to an in vivo dose of 8g/70kg) added to the dilutions. The fluids used were Voluven, Venofundin, Volulyte, Tetraspan, Albumin 5%, Macrodex, Gelofusine, Ringer’s acetate and NaCl. This covers the entire spectrum of fluids available in Sweden.

Results: A significant in vitro dilutive response compared to undiluted blood was seen for all synthetic colloid fluids but not for albumin or crystalloids. Dextran and Gelofusine’s impact on coagulation parameters was greater than both NaCl and Ringer’s acetate. The individual patient’s response showed a high variability, which was reflected in high standard deviations. No significant improvement from fibrinogen addition could be seen on Sonoclot parameters.

Conclusion: The dilutive effects of resuscitation fluids at 50% dilution are more severe for synthetic colloids compared to alternative therapies. Fibrinogen addition did not affect the induced coagulopathy as measured by the Sonoclot.