Acute normovolemic hemodilution: physiology, limitations, and clinical use

Acute normovolemic hemodilution before major surgery is a relatively simple, cheap, and effective tool to avoid or reduce allogeneic blood transfusions. The anesthesiologist, however, must be familiar with the practical aspects of ANH. In addition, knowledge of the physiologic compensatory mechanisms that occur during ANH and their limits are mandatory for the safe use of this blood-saving technique.The decision whether or not to perform ANH and to what level and the concomitant use of other blood-saving techniques must be made on an individual basis, based on the locally present knowledge and training of the involved anesthesia personnel and tailored to the patient’s needs to suit and serve him best.     

术前急性高容血液稀释在脑膜瘤切除术中的应用

目的观察脑膜瘤切除手术患者应用术前急性高容血液稀释(AHH)的临床效果及其对减少输入异体血量的影响。方法择期脑膜瘤切除术患者40例,随机分为I组血液稀释组(n=20)和II组对照组(n=20),两组患者均采用相同的麻醉方法全麻气管插管,I组术前进行高容血液稀释。比较两组患者输异体血量和术后血红蛋白变化。结果血液稀释组12例患者未输异体血,8例输异体血200~400ml,对照组每例患者均需异体血输入,输血量400~800ml,两组患者异体血输入量有显著性差异(P<0.05)。结论急性高容血液稀释可使脑膜瘤切除术患者明显减少异体输血或不输异体血。     

急性等容血液稀释用于子宫颈癌根治术的研究

目的了解急性等容量血液稀释在子宫颈癌根治术中对输异体血量的影响。方法择期子宫颈癌根治术患者16例,采用随机双盲方法分成两组,每组8例,Ⅰ组为对照组,Ⅱ组为血液稀释组,两组患者均采用两点连续硬膜外阻滞。Ⅱ组患者术前进行等容量血液稀释,比较两组患者术中所输异体血量和术后血红蛋白的变化。结果Ⅱ组患者有6例完全避免输异体血,余下2例患者各输异体血400mL,Ⅰ组每例患者均需要输异体血,输血量为400～800mL,显著多于Ⅱ组,两组患者术后血红蛋白、红细胞压积均比术前有所下降,但两组患者同期相比差异无统计学意义,均在安全范围。结论急性等容量血液稀释可使子宫颈癌根治术患者少输或不输异体血。     

万汶用于急性高容血液稀释的临床研究

目的：研究用万汶（第三代6％中分子羟乙基淀粉130／0．4）进行急性高容血液稀释对患者血流动力学、凝血功能、血气、电解质的影响。方法：选择20例ASAⅠ～Ⅱ级的成年患者，于手术开始前30min快速输注万汶1000mL，达到高容量血液稀释。检测稀释前后SBP、DBP、HR、PT、APTT、FIB、pH、PO2、Na^-、K^＊、Cl^-的变化。结果：用万汶进行急性高容血液稀释后循环功能稳定，凝血功能、血气、电解质均无明显变化。结论：用万汶进行急性高容血液稀释安全、有效。     

黄芪注射液加等容血液稀释疗法治疗老年脑梗死血瘀证的临床研究

目的:观察黄芪注射液和等容血液稀释疗法对脑梗死血瘀证的治疗作用.方法:选择64例住院及门诊脑梗死患者,同时符合血瘀证诊断标准,其中男43例,女21例;年龄63～76岁,平均(69.6±4.4)岁.随机分常规治疗组和等容血液稀释疗法加黄芪注射液治疗组,观察两组治疗前后血液流变学指标的变化,并于治疗3周后进行疗效评定.结果:黄芪注射液加等容血液稀释疗法治疗组临床疗效较常规治疗组好,临床总有效率为93.75%比87.50%,有显著性差异(P<0.05);治疗后全血黏度、血细胞比容及纤维蛋白原等指标均有显著的改善(P均<0.05).结论:对血瘀证的老年脑梗死患者采用等容血液稀释疗法加益气中药黄芪注射液治疗,具有较好的降低血黏度、促进血流、减轻临床症状、减轻致残率、提高脑梗死临床疗效的作用.     

羟乙基淀粉急性扩容性血液稀释对凝血功能的影响

目的比较6%羟乙基淀粉130/0.4和6%羟乙基淀粉200/0.5急性扩容性血液稀释时对神经外科手术患者凝血功能的影响。方法选择行择期神经外科手术的患者40例,随机分为6%羟乙基淀粉200/0.5组（H组,n=20）和6%羟乙基淀粉130/0.4组（V组,n=20）,于麻醉诱导后以500ml/30min的速度输注6%羟乙基淀粉130/0.4或6%羟乙基淀粉200/0.51500ml行急性扩容性血液稀释。于血液稀释前（T0）、输液1000m（lT1）、1500m（lT2）和血液稀释后30-60min（T3）时,取股静脉血监测凝血功能变化,包括激活凝血活酶时间（ACT）、凝血速（CR）、凝血达峰时间（TP）和血小板功能（PF）。结果在血液稀释过程中,两组血液稀释后ACT较稀释前显著缩短（P〈0.05）,H组在输液T1、T2和T3缩短幅度分别为18%、27%和20%,V组分别为16%、25%和21%,组间比较,差异无统计学意义（P〉0.05）。两组CR均下降,和稀释前比较,差异有统计学意义P〈0.05）,H组各时间点分别下降17%、37%和33%,V组分别下降18%、30%和27%。组间比较,差异无统计学意义（P〉0.05）。PF在稀释过程中V组下降幅度明显小于H组（P〈0.05）。TP在两组之间比较,V组延长幅度较小,两组之间在T2比较,差异有统计学意义（P〈0.05）。结论神经外科患者应用羟乙基淀粉溶液行急性扩容性血液稀释时,6%羟乙基淀粉130/0.4对于凝血功能的影响明显小于6%羟乙基淀粉200/0.5,临床使用更为安全。     

血液稀释用于围术期血液保护

围术期血液稀释可以有效地维持术中循环功能稳定,优化血液流变状态,改善微循环灌注,提高患者对失血的耐受性,减少异体输血量,降低输血引起的输血反应及感染血源性传染病的概率。合理的血液稀释对凝血曲线和凝血功能影响小,不干扰组织氧代谢水平,对脏器功能无明显不良影响。这一血液保护技术疗效确切,效果好,费用合理,值得推广。     

急性高容量血液稀释的临床应用

近年来,随着对血液保护的越发重视,血液稀释技术在临床的应用也越来越广泛,急性高容量血液稀释作为血液保护的一种新措施具有与急性等容性血液稀释同样的扩容效应,它减少术中失血,并具有操作简单、节约时间及费用、减少血液污染机会等优点。但在临床实际应用中仍有一些顾虑,如肺水肿的发生、机体氧代谢、凝血功能障碍、联合控制性降压的安全性等,本文就这些比较关注的问题予以综述。     

Acute normovolemic hemodilution, intraoperative cell salvage and PulseCO hemodynamic monitoring in a Jehovah's Witness with placenta percreta

A Jehovah’s Witness who had had four previous cesarean deliveries was referred to our institution for management of a complete placenta previa at 34 weeks of gestation. A subsequent ultrasound scan was suggestive of placenta percreta with bladder involvement. After erythropoietin and iron supplementation, cesarean hysterectomy was performed. Using PulseCO technology for continuous hemodynamic monitoring, preoperative acute normovolemic hemodilution and intraoperative cell salvage were used resulting in a successful cesarean hysterectomy with a 5500-mL estimated blood loss. The PulseCO system provides continuous, real-time hemodynamic data by applying pulse power analysis to the arterial pressure waveform. A bolus of oxytocin given after delivery produced profound hypotension, the hemodynamics of which were elucidated with the PulseCO system. To our knowledge, the combined use of acute normovolemic hemodilution, intraoperative cell salvage and PulseCO hemodynamic monitoring for cesarean hysterectomy has not been reported previously. These techniques may be particularly useful in managing patients who refuse blood products and/or in whom the baseline hemoglobin is suboptimal.