Prolonged Bleeding Times and Hypofibrinogenemia in Dogs After Infusion of Hydroxyethyl Starch and Dextran

Dogs bled 25 ml/kg were infused intravenously with 25 ml/kg of 6% solutions of hydroxyethyl starch (HES), medium molecular weight (75,000) dextran, or Tyrode's saline solution. Bleeding times from ear punctures with BD Microlances were significantly prolonged to a similar extent after HES and dextran infusion during periods of observation of up to 10 hours; the increment in bleeding times was less after saline infusion. Paw puncture bleeding times also increased after HES and dextran, but decreased after administration of saline. Ratios of fibrinogen to total plasma protein concentrations decreased to 93 ± S.E. 4% of preinfusion ratios after HES, but decreased more significantly to 81 ± 4% and 78 ± 4% after dextran and Tyrode's saline infusion.