急性高容血液稀释在急诊组合组织移植手术中的应用

目的探讨术前急性高容血液稀释（AHH）应用于急诊组合组织移植手术中的可行性。方法选择急诊组合组织移植的手术40例，随机分为术前急性高容血液稀释组（A组）、常规输液组（B组），每组20例。A组术前输入复方乳酸钠林格液8ml／kg，补充术前禁食量和生理需要量，用6％中分子羟乙基淀粉万汶^TM（6％HES130／0．4）15ml／kg行急性高容血液稀释；B组术前只输入复方乳酸钠林格液8ml／kg，术中输液同A组。观察急性高容血液稀释（AHH）前、后，手术完毕各组的心率（HR）、平均动脉压（MAP）、中心静脉压（CVP）、血氧饱和度（SpO2）、凝血功能、血常规、出血量及输血量。结果A组AHH后心率（HR）、脉搏氧饱和度（SpO2）稳定；CVP升高（P〈0．01）；血小板（PC）降低（P〈0．01）；血红蛋白（Hb）、血细胞比容（Hct）下降；APTr升高（P〈0．01），纤维蛋白原（FIB）浓度降低（P〈0．05），血液稀释明显，黏稠度下降，低凝，有利于组织灌注和静脉回流。A组输血1例，B组输血8例，差异有统计学意义。结论术前急性高容血液稀释（AHH）可安全应用于急诊组合组织移植手术，有效减少异体血的输注，明显降低血液黏稠度、降低血小板浓度、延长凝血时间，有利于急诊组合组织灌注和静脉回流。     

急性等容血液稀释对心肌钙蛋白和心肌酶的影响

目的 观察急性等容血液稀释（ANH）对心肌钙蛋白和心肌酶的影响,探讨急性等容血液稀释是否引起心肌损伤。方法 选择ASAⅠ～Ⅱ级,行择期肝切除术或双侧全髋置换术患者29例,随机分为血液稀释组（H组）和对照组（C组）。在麻醉前、输血前、术后4h和术后第一天采静脉血,测定肌酸激酶（CK）、肌酸激酶-MB（CK-MB）与心肌钙蛋白I（CTnI）。结果　（1）在输血前,H组血红蛋白比积（Hct）降低到20.33％±1.91％,C组降低到29.64％±1.78％,两者间差异显著（P<0.01）。（2）组间各相应时段的CK、CK-MB无显著性差异（P>0.05）。两组与基础值比较,CK于术后4h、术后第一天显著升高（P<0.01）;CK-MB于术后第一天显著升高（P<0.01）。（3）组间各相应时段和组内不同时段的Ctnl无显著性变化（P>0.05）;且一直处于低浓度（≤2.3ng·ml-1）结论 心肺等重要器官功能正常的病人,在术中吸入纯氧的条件下,等容血液稀释度Hct在约20％时,不会引起心肌的损伤。     

急性等容血液稀释对靶控输注异丙酚血药浓度及系统性能的影响

目的探讨急性等容血液稀释对靶控输注（TCI）异丙酚血药浓度及系统性能的影响。方法择期骨科手术患者35例,ASAⅠ级或Ⅱ级,随机分为稀释组（n=17）和对照组（n=18）。稀释组在麻醉诱导插管后,实施急性等容血液稀释,达稀释目标（Hct 0．25～0．27）10 min后,TCI异丙酚;对照组不行血液稀释,直接TCI异丙酚。设定血浆靶浓度3μg/ml,TCI异丙酚60 min,间断采血180 min,用气相色谱-质谱法测定异丙酚血药浓度并评价TCI系统的性能。结果稀释组的实测血药浓度低于对照组40．8％～73．1％（P＜0．05）。稀释组TCI系统偏离度、精确度和摆动度分别为-8．83％、22．98％和22．12％。结论急性等容血液稀释降低了异丙酚TCI的实测血药浓度,优化了TCI的系统性能。     

硬通道微创技术在抢救外伤性颅内血肿合并脑疝患者中的应用

目的探讨硬通道微创技术在外伤性颅内血肿合并脑疝形成患者术前的应用价值。方法回顾分析2004年1月～2007年6月因外伤引起的急性硬膜外、急性硬膜下血肿合并脑疝71例资料。急救引流＋手术组（n=30）于术前脑疝明确诊断后快速应用硬通道微创技术引流血肿，手术组（n=41）直接手术。2组均常规行血肿清除及去骨瓣减压术，术后治疗方法相同。结果2组年龄、性别、术前格拉斯哥昏迷评分（GCS）、血肿量和部位、中线移位、瞳孔散大等差异无显著性。术后3个月格拉斯哥预后评分（GOS）急救引流＋手术组良好6例、中残13例、重残4例、植物生存2例、死亡5例，手术组分别为5例、8例、12例、7例、9例，2组有显著差异（Z=-2．001，P=0．045）。结论术前及早辅助硬通道微创技术治疗能够改善外伤性颅内血肿合并脑疝患者的预后．可单成为抢救此类病人的常规。     

急性等容血液稀释对血液动力学及氧代谢的影响

目的 研究术前急性等容血液稀释对血液动力学和氧代谢的影响。方法 20例肝癌切除术病人,随杨分为血液稀释组（I组,n=10)和对照组（Ⅱ组,n=10)。I组于全麻后采血,将血红蛋白稀释到80－90g/L,同时输入两倍于采血量的晶胶体溶液。在稀释前后各时点监测血液动力学、氧代谢以及动脉血乳酸等参数。结果 I组于血液稀释后,心脏指数（CI）和每搏指数（SI）维持稳定,氧输送量（DO2）降低（P＜0．01）,但仍高于临界氧输送值。结论 在吸入高浓度氧的情况下,中度血液稀释无明显的心血管代偿反应,不引起氧输送不足。     

急性高容量血液稀释对患者靶控输注异丙酚时镇静深度的影响

目的 观察急性高容量血液稀释（AHH）对患者靶控输注（TCI）异丙酚时镇静深度的影响。方法 择期全麻患者80例，随机分为4组（n=20）：A组、B组、C组气管插管后5min均开始进行急性高容量血液稀释，静脉输注乳酸钠林格氏液8ml／kg，同时30min内静脉输注6％羟乙基淀粉（HES，200／0．5）15ml／kg。B0组为B组的对照组，只静脉输注乳酸钠林格氏液8ml／kg，不进行急性高容量血液稀释。A组、B组、B0组、C组分别以2、4、4、6μg／ml异丙酚效应室靶浓度实施靶控输注至血液稀释结束。监测各组开始血液稀释即刻、5、10、15、20、25、30min时的BIS、AAI、MAP、HR、SpO2及ECG的变化，采集血标本，检测血液稀释前即刻和血液稀释结束时的Hct、Hb。结果 与B0组比较，B组MAP升高，BIS和AAI降低（P〈0．05或P〈0．01），血液稀释结束时Hct、Hb下降（P〈0．01）。随AHH的进行A组和B组MAP逐渐上升，BIS、AAI逐渐下降（P〈0．05或P〈0．01），Bn组和C组的MAP、BIS、AAI无明显变化，4组HR、SpO2差异无统计学意义（P〉0．05）；与血液稀释前即刻比较，A组、B组、C组在血液稀释结束时的Hct、Hb降低（P〈0．01），Bn组无变化（P〉0．05）。结论 患者以异丙酚2、4μg／ml效应室靶浓度靶控输注时，急性高容量血液稀释可加深镇静深度，当效应室靶浓度升为6μg／ml时，对其镇静深度无明显影响。     

急性等容血液稀释在人工关节置换术中的应用

目的评价急性等容血液稀释在人工关节置换术围手术期的治疗效果以及异体血节约程度。方法回顾分析120例初次单侧人工关节置换术患者,对照组60例未进行自体血回输,实验组60例实施自体血回输,对比两组术前以及术后第2天的血红蛋白（Hb）、红细胞压积（Hct）、白蛋白（Alb）水平和术后2 d内录输注红细胞悬液和新鲜冰冻血浆的剂量。结果实验组与对照组在年龄、性别、手术类型间无统计学差异（t年龄=2.123,t性别=2.208,t手术类型=0.138,P均大于0.05）。实验组与对照组的术后Hb、术后Hct、术前Alb间无统计学差异（t术后Hb=-0.233,t术后Hct=0.310,t术前Alb=-1.698,P均大于0.05）。实验组术前Hb（140.58±13.92）g/L、术前Hct（40.43±3.83）高于对照组术前Hb（132.15±14.50）g/L、Hct（37.97±6.19）（t术前Hb=-3.251,t术前Hct=-2.626,P均小于0.05）。实验组术后Alb水平（32.70±2.05）g/L略低于对照组（33.80±3.11）g/L（t术前Alb=-1.698,t术后Alb=2.188,P均小于0.05）。实验组围手术期人均红细胞悬液和新鲜冰冻血浆使用量分别较对照组减少1.77 IU和2.45 IU（P〈0.001）。结论急性等容血液稀释自体血回输治疗在人工关节置换围手术期能够显著降低异体红细胞悬液和新鲜冰冻血浆的用量,同时不影响术后Hb以及Hct的水平。     

急性高容量血液稀释对血液流变特性影响的临床研究

目的 观察急性高容量血液稀释（AHH）后血液流变学特性的变化。为临床合理应用血浆代用品提供研究依据。方法 60例骨科手术患者随机分为三组，每组20例，按20ml/kg的扩容量分别输注6%羟乙基淀粉，复方氯化钠和4%琥珀酰明胶，达到高容量血液稀释，检测稀释前后全血粘度，血浆粘度，Hct，红细胞聚集指数，红细胞变形指数。结果 （1）AHH后循环功能稳定，围术期异体血输入量胶体液组明显少于晶体液组。（2）AHH后全血粘度，Hct明显降低，红细胞聚集指数降低，红细胞变形指数6%羟乙基淀粉组升高。结论 术前AHH可以有效地维持术中循环功能稳定，优化血液流变状态，利于微循环灌注，提高患者对失血的耐受性。减少异体血输入量，胶体溶液优于晶体溶液。     

6%羟乙基淀粉急性高容性血液稀释在儿科病人的应用

目的研究6%羟乙基淀粉用于婴幼儿和儿童对于血液流变学、血小板功能和凝血功能等的影响.方法20例手术病人按年龄分为婴幼儿组（Ⅰ组,〈3岁,n=9）和儿童组（C组,3～12岁,n=11）,术前用6%羟乙基淀粉10 ml/kg行高容性血液稀释,输液前后分别抽取颈静脉血测定血液流变学、血小板功能和凝血功能,比较各组输液前后以及两组之间的变化.结果两组病人输液后全血低切、中切和高切粘度均显著下降（P〈0.01）,但血浆粘度无显著改变;两组病人血细胞比容、纤维蛋白原在输液后均显著下降（P〈0.01）;红细胞聚集指数、刚性指数、变形指数在输液前后无显著变化;与输液前比较,输液后红细胞电泳指数显著增加（P〈0.05）;两组病人血沉、血小板计数和血小板聚集率、部分凝血活酶时间在输液后无显著变化;C组病人输液后凝血酶原时间显著延长.两组间各项指标相同时点比较虽有一定变化,但无显著性差异（P＞0.05）.结论6%羟乙基淀粉用于1～12岁儿科病人进行术前急性高容性血液稀释,能改善血液流变性,稳定血液动力学,但对凝血功能无影响,不增加出血倾向.     

不同程度急性等容量血液稀释对兔小肠粘膜的影响

目的 探讨常温下不同程度急性等容量血液稀释(ANH)对家兔小肠粘膜的影响.方法 选择健康成年家兔32只,体重2.0～2.5 kg,随机分为4组(n=8),对照组(C组)不行血液稀释;其余3组血液稀释的目标Hct分别为24%(H1组)、18%(H2组)和12%(H3组).经股动脉放血:H1组、H2组、H3 组所需放血量=2×体重×每公斤体重所含体液量×(初始Hct-目标Hct)/(初始Hct+目标Hct),股静脉经30 min输入等容量6%羟乙基淀粉200/0.5行ANH.于ANH前(T0)及ANH后8 h(T1)时采集肠系膜上静脉血样0.5 ml,采用酶联免疫吸附法测定血浆TNF-α浓度.于T1时取小肠粘膜组织,观察病理学结果.结果 与T0时比较,T1时H2组、H3组肠系膜上静脉血浆TNF-α浓度升高(P＜0.01),H1组差异无统计学意义(P＞0.05).与C组比较,H2组和H3组肠系膜上静脉血浆TNF-α浓度升高(P＜0.01),H1组差异无统计学意义(P＞0.05).H1组小肠粘膜未见明显损伤,H2组轻度损伤,H3组损伤严重.结论 6%羟乙基淀粉200/0.5行ANH,当Hct为24%时,对家兔小肠粘膜无明显影响;当Hct≤18%时,可诱发小肠粘膜损伤.     

两种自体输血方式在中央性前置胎盘孕妇中应用的安全性分析

目的探讨储存式自体输血和急性等容稀释式自体输血在中央性前置胎盘孕妇剖宫产术中应用的安全性及临床疗效。方法选择2013年1月至2016年9月在我院因中央性前置胎盘拟行剖宫产术的60例患者为研究对象。采用随机数字表的方法平均分为两组:A组为储存式自体输血组,B组为急性等容稀释式自体输血组。观察两组患者自体输血采血前后及手术后的血红蛋白(Hb)、血细胞比容(Hct)、血小板计数(PLT)、术中出血量、输血量、新生儿Apgar评分及Hb水平、输血不良反应等。结果两组患者出血量及输血量比较无显著性差异(P0.05)。两组患者采血前后及手术后的Hb、Hct、PLT比较亦无显著性差异(P0.05)。两组新生儿1分钟Apgar评分及Hb水平比较无显著性差异(P0.05)。两组患者中输注自体血的患者均未发生输血不良反应,术后恢复良好;输注异体血的患者中,B组仅有1例出现发热、皮疹,未出现严重不良反应。结论储存式自体输血和急性等容稀释性自体输血在应用安全性上无明显差异。在基层医院临床工作中,针对中央性前置胎盘患者,由于剖宫产输血率高,可以在综合评估患者具体情况后,对必要的患者选择自体输血。     

Splanchnic perfusion during controlled hypotension combined with acute hypervolemic hemodilution: a comparison with combination of acute normovolemic hemodilution-gastric intramucosal pH study

STUDY OBJECTIVE: To evaluate the effect of controlled hypotension combined with acute hypervolemic or normovolemic hemodilution on the splanchnic perfusion in the clinical setting. DESIGN: Randomized, prospective study. SETTING: Inpatient surgery at Nagasaki Rosai Hospital. PATIENTS: 28 ASA physical status I and II patients scheduled for total hip arthroplasty.Interventions: Patients were randomly divided into two groups. Group A (n = 14) received controlled hypotension with acute normovolemic hemodilution (ANH). Group B (n = 14) received controlled hypotension with acute hypervolemic hemodilution (HHD). ANH was produced by drawing approximately 1000 mL of blood and replacing it with the same amount of 6% hydroxyethyl starch solution (HES). HHD was produced by preoperative infusion of 1000 mL of 6% HES without removing blood. The final hematocrit values were 24+/-2% (mean +/- SD) in Group A and 25+/-3% in Group B. Controlled hypotension was induced with prostaglandin E1 (PGE1) to maintain mean arterial blood pressure at 55 mmHg for 80 minutes. MEASUREMENTS: Measurements included the gastric pH (pHi), the arterial blood pH (pHa), and plasma lactate. These indices were measured before hemodilution, after hemodilution, 80 minutes after starting hypotension, 60 minutes after recovery from hypotension, and on the first postoperative day. The value of pHi was measured by tonometric method. MAIN RESULTS: The pHa and lactate values showed no change in either group A or group B throughout the time course. Gastric pHi values in group A showed a significant decrease from 7.424+/-0.033 to 7.335+/-0.038 (p<0.05) after hemodilution, whereas it showed no further decrease at 80 minutes after starting hypotension and 60 minutes after recovery from hypotension. The pHi values in group B showed no significant decrease after hemodilution and no further change at 80 minutes after starting hypotension. CONCLUSIONS: HHD does not impair splanchnic perfusion, whereas ANH might cause impairment. Controlled hypotension with prostaglandin E1 would not impair splanchnic perfusion in combination with either HHD or ANH.     

地氟醚与七氟醚对颅脑肿瘤手术患者血糖和乳酸的影响

目的研究地氟醚与七氟醚对颅脑肿瘤手术患者血糖和乳酸的影响。方法选择择期行颅脑肿瘤切除的患者64例,年龄21～62岁,ASA分级Ⅰ～Ⅱ级,体质指数20～25 kg/m2,采用随机数字表法分为地氟醚组(Group Des,n=30)与七氟醚组(Group Sevo,n=34),分别采用地氟醚、七氟醚吸入麻醉。分别于手术前(T0)、手术1小时(T1)、手术2小时(T2)、手术结束(T3)取动脉血1 m L,检测血糖和乳酸水平。结果两组患者血糖均升高,在四个不同时间点的比较差异有统计学意义(P0.01);各组在各时间点的比较无统计学意义(P0.05)。两组患者乳酸无明显升高,在各时间点的比较无统计学意义(P0.05);各组在各时间点的比较无统计学意义(P0.05)。结论地氟醚与七氟醚麻醉均增加颅脑肿瘤患者血糖水平。     

Effectiveness of acute normovolemic hemodilution to minimize allogeneic blood transfusion in major liver resections

BACKGROUND: Liver resection is a major operation for which, even with the improvements in surgical and anesthetic techniques, the reported rate of blood transfusion was rarely less than 30%. About 60% of transfused patients require only 1 or 2 units of blood, a blood requirement that may be accommodated by the use of acute normovolemic hemodilution (ANH). METHODS: The efficacy, hemodynamic effects, and safety of ANH were investigated in a randomized, active-control study in patients with American Society of Anesthesiologists status I-II who were undergoing major liver resection with fentanyl-nitrous oxide-isoflurane anesthesia. Patients were randomized to the ANH (n = 39) or control group (n = 39). Patients in the ANH group underwent hemodilution to a target hematocrit of 24%. The indication for blood transfusion was standardized. In both groups transfusion was started at a hematocrit of 20%. The primary efficacy endpoint was the avoidance of allogeneic blood transfusion in the intraoperative period and first 72 h after surgery. Various laboratory and hemodynamic parameters as well as postoperative morbidity were monitored to define the safety of ANH in this patient population. RESULTS: During the perioperative period, 14 control patients (36%) received at least one unit of allogeneic blood compared with 4 patients (10%) in the ANH group ( < 0.05). The hemodilution process was not associated with significant changes in patients' hemodynamics. Morbidity was similar between the control and the ANH groups. Postoperative hematocrit levels and biochemical liver, renal, and standard coagulation test results were similar in both groups. CONCLUSIONS: Acute normovolemic hemodilution in patients with American Society of Anesthesiologists status I-II undergoing major liver resection may allow a significant number of patients to avoid exposure to allogeneic blood.     

不同消化道重建方式对胃癌合并2型糖尿病患者血糖的影响

目的探讨胃癌合并2型糖尿病患者行不同消化道重建手术方式对血糖的影响。方法回顾性分析我院2010年1月~2012年12月收治的53例远端胃癌合并2型糖尿病患者的临床资料,根据消化道重建方式分为两组:Ⅰ组25例,采用BillrothⅠ式手术行消化道重建;Ⅱ组28例,采用BillrothⅡ式手术行消化道重建。比较两组术后血糖的变化及疗效。结果Ⅰ组术后空腹血糖(FBG)、OGTT 2h血糖(2h PBG)、糖化血红蛋白(Hb A1c)及空腹C肽与术前比较均无明显变化(均P0.05),Ⅱ组术后FBG、2h PBG及Hb A1c较术前明显降低(均P0.05),空腹C肽较术前明显升高(P0.05)。两组患者术后FBG、2h PBG、Hb A1c及空腹C肽等指标比较均具有统计学差异(均P0.05)。Ⅰ组临床有效率为20%,Ⅱ组为92.9%,组间比较差异具有统计学意义(χ2=28.876,P0.01)。结论 BillrothⅡ式消化道重建方式对于胃癌合并2型糖尿病患者具有一定的血糖控制作用。     

Influence of normovolemic hemodilution on the respiratory and circulatory systems]

We studied respiratory and circulatory kinetics of normovolemic hemodilution in adult mongrel dogs. The dogs were divided into two groups; Dextran-40 (group A) and SALIN-HES (group B). No difference in PaO2 and PaCO2 was noted between the two groups. MPA and CI during normovolemic hemodilution were higher in group A than in group B. However, MPA, Qs/Qt and ETVI during normovolemic hemodilution were largely influenced in group A. L/P during normovolemic hemodilution was more influenced in group B than in group A. The compensatory effect with increase of the cardiac output during normovolemic hemodilution was noted until S3 (Hct = 10%), but it was not noted at S4 (Hct = 5%) and S5 (just before death). SvO2 is the most sensitive index indicating the risk of normovolemic hemodilution.     

Transfusion free surgery: single institution experience of 27 consecutive liver transplants in Jehovah's Witnesses

BACKGROUND: Despite the risks associated with transfusion, the medical community continues to view blood as a safe and abundant product. In this article, we provide an effective strategy to accomplish orthotopic liver transplantation without transfusion. STUDY DESIGN: From June 1999 through July 2004, 27 liver transplantations were performed in Jehovah's Witness patients at the USC-University Hospital (24 adults, 3 children). Nineteen of these were living donor (LD) and eight were deceased donor (DD) liver transplants. Preoperative blood augmentation with erythropoietin and iron was achieved. At induction, all LD and six of eight DD recipients underwent acute normovolemic hemodilution (ANH), and the operation was conducted under conditions of moderate anemia. Cell scavenging techniques were used. Acute normovolemic hemodilution and salvaged blood were returned as needed during bleeding or on completion of transplantation. RESULTS: The preoperative liver disease severity score was higher in the deceased donor group. We had 100% graft and patient survivals in the LD group, and 75% in the DD recipients. Two DD recipients died. The remaining are all alive and well, with a mean followup of 965 days (range 266 to 1,979 days) in the LD group and 624 days (range 119 to 1,132 days) in the DD group. CONCLUSIONS: Preoperative blood augmentation and acute normovolemic hemodilution provide a safe cushion against operative blood loss. Elective living donor liver transplantation allows full implementation of a transfusion-free strategy in the setting of early hepatic failure, portal hypertension, and anemia. This feat is an important step toward global standardization of transfusion-free surgical practice and an important response to widespread blood shortages and transfusion risks.     

血液稀释对控制性降压下血清胱抑素C的影响

目的探讨急性等容性血液稀释对控制性降压期间血清胱抑素（Cys-C）的影响。方法选择40例择期脊柱手术病人,随机分为4组,对照组、控制性降压组、血液稀释组和血液稀释联合控制性降压组,每组10例。用0.01%硝普钠进行控制性降压,将MAP维持在60～70mmHg;通过静脉采血和输液进行血液稀释,将Hct降至25%～30%;测定Cys-C含量。结果控制性降压组Cys-C含量明显升高（P〈0.05）。结论单纯控制性低血压可使肾小球滤过率（GFR）降低,而联用血液稀释则对肾功能有保护作用。     

Effect of high- and low-molecular-weight low-substituted hydroxyethyl starch on blood coagulation during acute normovolemic hemodilution in pigs

BACKGROUND: Hydroxyethyl starches (HES) with lower impact on blood coagulation but longer intravascular persistence are of clinical interest. The current study aimed to investigate in vivo the isolated effect of molecular weight on blood coagulation during progressive acute normovolemic hemodilution. METHODS: Twenty-four pigs were normovolemically hemodiluted up to a total exchange of 50 ml . kg . body weight of HES 650/0.42 or HES 130/0.42. Serial blood sampling was performed to measure HES plasma concentration and to assess blood coagulation. Concentration-effect relations were analyzed by linear regression, followed by the Student t test on regression parameters. RESULTS: Blood coagulation was increasingly compromised toward hypocoagulability by acute normovolemic hemodilution with both treatments (P < 0.01). Significantly greater impact on activated partial thromboplastin time (P = 0.04) and significantly stronger decrease of maximal amplitude (P = 0.04), angle alpha (P = 0.02), and coagulation index (P = 0.02) was seen after acute normovolemic hemodilution with HES 650/0.42 as compared with HES 130/0.42. Except for factor VIII (P = 0.04), no significant differences between both treatments were observed when relating antihemostatic effects to HES plasma concentrations (P > 0.05). A significantly lesser decrease of hemoglobin concentration has been found with HES 650/0.42 as compared with HES 130/0.42 (P < 0.01) in relation to HES plasma concentrations. CONCLUSION: High-molecular-weight HES (650/0.42) shows a moderately greater antihemostatic effect than low-molecular-weight HES (130/0.42) during acute normovolemic hemodilution. However, similar effects on hemostasis were observed with both treatments when observed antihemostatic effects were related to measured HES plasma concentrations. In addition, HES 650/0.42 may have a lower efficacy in immediately restoring plasma volume.