Effects of Acute Normovolemic Hemodilution on Perioperative Coagulation and Fibrinolysis in Elderly Patients Undergoing Hepatic Carcinectomy

Objective To observe the effects of acute normovolemic hemodilution （ANH） on coagulation function and fibrinolysis in elderly patients undergoing hepatic carcinectomy. Methods Thirty elderly patients （aged 60-70 years） with liver cancer （American Society of Anesthesiologists physical status I-II） scheduled for hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group （n= 15） and control group （n= 15）. After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch （HES） （130/0.4）, and basic liquid containing 6% HES and routine Ringer＇s solution, respectively. In all the studied patients, blood samples were drawn at five different time points： before anesthesia induction （T1）, 30 minutes after ANH （T2）, 1 hour after start of operation （T3）, immediately after operation （T4）, and 24 hours after operation （Ts）. Then co- agulation function, soluble fibrin monomer complex （SFMC）, prothrombin fragment （F1＋2）, and platelet membrane glycoprotein （activated GPIIb/GPIIIa and P-selectin） were measured. Results The perioperative blood loss was not significantly different between the two groups （P〉 0.05）. The volume of allogeneic blood transfusion in ANH group was significantly smaller than that in control group （350.5±70.7 mL vs. 457.8±181.3 mL, P〈0.01）. Compared with the data ofT1, prothrombin time （PT） and activated partial thromboplastin time in both groups prolonged significantly after T3 （P〈0.05）, but still within normal range. There were no significant changes in thrombin time and D-dimer between the two groups and between different time points in each group （all P〉0.05）. SFMC and F1 ＋2 increased in both groups, but without statistical significance. P-selectin expression on the platelet surface of ANH group was significantly lowered atT2 andT3 compared with the level atT1 （P〈 0.05）. Compared with control group, P-selectin was sig-nificantly lower in ANH group atT2-T3 （all P〈0.05）. Conclusions In elderly patients undergoing resection of liver cancer, ANH may not hamper fibri- nolvsis and coagulation function. It coukt therefore be safe to largely reduce allogeneic blood transfusion.

Effects of different plasma expanders on rats subjected to severe acute normovolemic hemodilution

Background:Plasma expanders are widely used for acute normovolemic hemodilution(ANH).However,existing studies have not focused on large-volume infusion with colloidal plasma expanders,and there is a lack of studies that compare the effects of different plasma expanders.Methods:The viscosity,hydrodynamic radius(Rh)and colloid osmotic pressure(COP)of plasma expanders were determined by a cone-plate viscometer,Zetasizer and cut-off membrane,respectively.Sixty male rats were randomized into five groups with Gelofusine(Gel),Hydroxyethyl Starch 200/0.5(HES200),Hydroxyethyl Starch 130/0.4(HES130),Hydroxyethyl Starch 40(HES40),and Dextran 40(Dex40),with 12 rats used in each group to build the ANH model.ANH was performed by the withdrawal of blood and simultaneous infusion of plasma expanders.Acid-base,lactate,blood gas and physiological parameters were detected.Results:Gel had a lower intrinsic viscosity than HES200 and HES130(P<0.01),but at a low shear rate in a mixture of colloids,red cells and plasma,Gel had a higher viscosity(P<0.05 or P<0.01,respectively).For hydroxyethyl starch plasma expanders,the COP at a certain concentration decreases from 11.1 mmHg to 6.1 mmHg with the increase of Rh from 10.7 nm to 20.2 nm.A severe ANH model,with the hematocrit of 40%of the baseline level,was established and accompanied by disturbances in acid-base,lactate and blood gas parameters.At the end of ANH and 60 min afterward,the Dex40 group showed a worse outcome in maintaining the acid-base balance and systemic oxygenation compared to the other groups.The systolic blood pressure(SBP),diastolic blood pressure(DBP),and mean arterial pressure(MAP)decreased significantly in all groups at the end of ANH.The DBP and MAP in the Dex40 group further decreased 60 min after the end of ANH.During the process of ANH,the Dex40 group showed a drop and recovery in SBP,DBP and MAP.The DBP and MAP in the HES200 group were significantly higher than those in the other groups at some time points(P<0.05 or P<0.01).Conclusions:Gel had a low intrinsic viscosity but may increase the whole blood viscosity at low shear rates.Rh and COP showed a strong correlation among hydroxyethyl starch plasma expanders.Dex40 showed a worse outcome in maintaining the acid-base balance and systemic oxygenation compared to the other plasma expanders.During the process of ANH,Dex40 displayed a V-shaped recovery pattern for blood pressure,and HES200 had the advantage in sustaining the DBP and MAP at some time points.

Safety and efficacy of acute normovolemic hemodilution during liver surgery: a Meta-analysis

Objective The aim of this study was to evaluate the safety and efficacy of acute normovolemic hemodilution(ANH) during liver surgery.Methods Structured searches of the Pub Med,Chinese Biological Medicine Database,and Cochrane Library electronic databases were performed,followed by a meta-analysis of outcomes,including intraoperative blood transfusion(s),intraoperative bleeding,postoperative hematocrit(Hct) levels,postoperative prothrombin time(PT),and number of patients who underwent transfusions during liver surgery.Results In total,14 eligible studies were included in the meta-analysis,which revealed that ANH for liver resection was associated with a reduction in intraoperative blood transfusions [weighted mean difference(WMD)-1.99;95% confidence interval(CI)-2.82 to -1.16;P<0.00001].The ANH group experienced less intraoperative bleeding(WMD -72.81;95% CI -136.12 to -9.50;P<0.00001) and exhibited a lower postoperative Hct level(WMD -3.38;95% CI -7.14 to -0.67;P<0.00001) than the control group.Moreover,meta-analysis revealed that postoperative prothrombin time was not affected by ANH(WMD -0.02;95% CI -0.18 to -0.32;P=0.65).Finally,the number of patients requiring allogeneic transfusion was significantly smaller in the ANH group than in the control group(odds ratio 0.13;95% CI 0.09 to 0.18;P=0.24).Conclusion Results of the present meta-analysis indicated that ANH can reduce intraoperative bleeding and the need for blood transfusions.In addition,ANH did not negatively affect the coagulation system after surgery;therefore,ANH appears to be safe and effective during liver surgery.

The role of acute normovolemic hemodilution in reducing allogeneic blood transfusion in glioblastoma surgery:a case-control study

Background Acute normovolemic hemodilution(ANH)was first introduced in glioblastoma surgery,and its role in reducing allogeneic blood transfusion was investigated in this study.Methods This study enrolled supratentorial glioblastoma patients who received total resection.In the ANH group,the patients were required to draw blood before the operation,and the blood will be transfused back to the patient during the operation.The association between ANH and clinical features was investigated.Results Sixty supratentorial glioblastoma patients were enrolled in this study,25 patients were allocated in the ANH group,and another 35 patients were included in the control group.ANH dramatically reduced the need for allogeneic blood transfusion(3[12%]vs 12[34.3%],P=0.049),and the blood transfusion per total of patients was dramatically decreased by the application of ANH(0.40±1.15 units vs 1.06±1.59 units,P=0.069).Furthermore,ANH also markedly reduced the requirement of fresh frozen plasma(FFP)transfusion(2[8%]vs 11[31.4%],P=0.030)and the volume of FFP transfusion per total of patients(32.00±114.46 mL vs 115.71±181.00 mL,P=0.033).The complication rate was similar between the two groups.Conclusions ANH was a safe and effective blood conservation technique in glioblastoma surgery.