Acute hypervolemic hemodilution for reducing perioperative blood use

Objective To study the feasibility of preoperative acute hypervolemic hemodilution for decreasing perioperative blood use. Methods Thirty two patients(ASAI-II) undergoing spinal surgery were randomized into AHH group and control group. After anesthesia 6% HES(200/0.5) was given through internal jugular vein for AHH. The blood volume was increased by about 25%. During the operation, blood loss was replaced by HES in equal volume. Blood was transfused when the Hct dropped below 25%. The HR, MAP, CVP, SPO2, Hb, Hct., Plt, FIB, APTT, PT, amount of blood loss, blood transfused and urine output, volume of drainage 24h after operation and VAS score (0 means no effect, 10 means maximal effect) were observed before AHH, at the end of AHH, at the end of operation, and 24h after the operation. Blood volume expansion was calculated. Results (1) HR increased significantly in both groups(P0.01)). In AHH group the MAP and CVP increased by 11% and 88% respectively at the end of AHH. (2) The amount of blood transfusion in AHH group was (447±209)ml, significantly less than control group of(832±311)ml. Twenty-five percent of patients in study group were transfused, compared to 44% in the control. But the difference was not statistically significant. (3)Hb and Hct decreased at all time points in two groups. (4)In AHH group both Plt and FIB decreased at the end of AHH, and end of operation, but Plt increased at 24h after operation(P0.01). In the control group both Plt and FIB increased significantly at 24hs after operation(P0.01). APTT and PT prolonged significantly but still were in normal range in AHH group. As for VAS score there was no difference between two groups . Conclusion Using AHH to reduce red blood cells loss and the amount of transfusion was feasible, also it had little influence on the circulation and blood coagulation functions.