Haes steril

The animals were randomly divided into 5 groups (12 rats for each group), as follows: 1) Gel group, 4% Succinylated Gel (Gelofusine®, B. Braun, Shenyang, China); 2) HES200 group, 6% HES 200/0.5 (HAES-steril®, Fresenius-Kabi, Bad Homburg, Germany); 3) HES130 group, 6% HES 130/0.4 (Voluven®, Fresenius-Kabi, Bad Homburg, Germany); 4) HES40 group, 6% HES40 (Shandong Qidu Pharmaceutical Co. China); and 5) Dex40 group, 6% Dextran 40 (Shandong Qidu Pharmaceutical Co. China). Each injection contained NaCl solution (0.9%).

Fresh blood samples were obtained from the right femoral arterial catheter using heparin-treated tubes (15 U/mL). The rat blood was centrifuged for 5 min at 1,500 × g and adjusted to a hematocrit of 40% by adding or removing autologous plasma. To represent the clinically relevant colloid plasma peak levels reported in the literatures [9 (link),17 (link),18 (link)], the well-distributed erythrocyte samples were subsequently diluted with 6% HES 130/0.4 (HES 130) (Voluven®, Fresenius-Kabi, Bad Homburg, Germany), 6% HES 200/0.5 (HES 200) (HAES-steril®, Fresenius-Kabi, Beijing, China), 4% succinylated gelatin (GEL, 30 kDa) (Gelofusine®, B. Braun, Shenyang, China), or LR (Juneng, Siping, China); the volume ratios of blood with the test solutions are 5:1 and 3:1. The control group consisted of the erythrocyte suspension without dilution.
All samples were incubated for 15 min at 37°C, and then, blood samples were adjusted to a hematocrit of 40% before measuring the hemorheological parameters. The plasma was obtained using centrifugation to detect the viscosity. All rheological measurements were carried out at a temperature of 37°C, which are in accordance with the international guidelines for the measurement of hemorheological parameters [19 (link)].