【作者】 梁淑娟；

【导师】 马虹；

【作者基本信息】 中国医科大学 ， 麻醉学， 2004， 硕士

【摘要】 前言 输血可能会引起感染、过敏、免疫力降低等各种并发症，减少术中输血是当前亟待解决的问题。急性等容血液稀释（acute normovolemic hemodilution，ANH）已被证实能有效地减少术中失血，但它费时费力，且有感染的危险。急性高容血液稀释（acute hypervolemic hemodilution，AHH）是指在术前输注一定量的晶体或胶体液而不采集自体血，术中出血量用等量的胶体液来补充，尿液和术野蒸发的水分均用等量的晶体液来补充，从而使血容量始终保持于术前高容状态。一种常用的稀释方法是在术前以50ml·min^-1的速度按15ml·kg^-1输入胶体液，使病人Hct降低，为避免高血容量所致的不良血流动力学效应，常采用吸入麻醉药、椎管内阻滞、血管扩张剂进行控制性降压（controlled hypotention，CH）来预防。AHH复合CH能够减少手术出血，降低异体输血率已得到国内外许多学者的认可，但AHH复合CH对组织器官氧供需平衡和组织灌注方面的影响报导较少。乳酸、混合静脉血氧饱和度（SvO₂）、氧摄取率（ERO₂）等是衡量全身组织器官氧供需平衡的可靠指标。本研究通过观察AHH与CH联合应用时血流动力学的变化，以及对血气、乳酸、离子和氧供需平衡的影响，评估联合应用的有效性和安全性。 实验材料 1．仪器：Detex．Omeda110麻醉机（美国）；惠普多功能监护仪（美国）；贝朗输液泵（德国）；Bayer血气电解质分析仪（美国）；强生全自动化学分析仪250型（美国）。 2．药品：6％羟乙基淀粉（贺斯，德国费森尤斯公司生产）；异氟醚（亚培制药）；硝普钠（北京，双鹤药业）。 实验方法 （一）病例选择 选择中国医科大学第一临床学院骨外科病人铭例，户‘SA分级I一n级，预行出血较多的择期手术，手术种类包括全镜关节置换术、胸椎和腰椎手术、骸臼骨折和股骨骨折内固定术等。术前无心、肝、肾等重要器官的功能障碍，无高血压和心肺疾病及血液系统疾病，血红蛋白（姚）>129·L!一’红细胞压积（Hct）>35%。将病人随机分为4组，每组12例。A组为对照组，B组为单纯控制性降压组，C组为单纯急性高容血液稀释组，D组为高容血液稀释复合控制性降压组。 （二）麻醉方法 所有病人术前30分安定10mg日服，阿托品仓，smg肌，注。静注咪哇安定0 .04mg·kg一’、芬太尼4ug。峪一‘、‘异丙酚1.5一2鸣·鳅一’、维库澳铰0，.1 mg·kg一‘后行气管内插管控制呼吸，」设置呼吸参数为:潮气量8一1o碰·kg一‘，呼吸次数12次/min。维库漠按间断静注维持肌松，异氟醚1一3%及NZO/O:按1:1吸人维持麻醉。麻醉诱导后行右颈内静脉穿刺置管人右心房，行挠动脉穿刺置管，留置尿管。术中四组病人均以.8一10司·kg一’·h一’的速度持续输注乳酸钠林格氏液，输人等量的胶体来补充失血量，等量的乳酸钠林格氏液来补充尿量，Hb<759·L一’时开始输血。 （三）稀释和降压 ·在麻醉插管后，C、D两组病人以50耐·n‘n一，的速度输注6%经乙基淀粉巧耐·kg一’，B、D组在开皮后约2o分钟左右（显露翁关节、卜椎体、骨折部位时）开始缓慢降压，持续静脉输注硝普钠（。，1一209·kg一’·min一’），术中根据降压目标调整硝普钠的用量，手术关键步骤结束时停止降压。 （四）观测指标 1.连续监测SBP、DBP、MAP’、HR、ECG、孙仇、Cvp和每小时尿量。 2.分别于插管后稀释前（T0）、稀释后即刻（T，）、.稀释后1小时（TZ）、术后即刻（毛）、术后24小时（几）分别采集混合静脉血和动脉血，，测定各时点的动脉血气包括Hb、Hct、动脉血氧含量（Ca仇）和离子，、乳酸，混合静脉血氧饱和度（S亏02）、血氧含量（C亏O:），计算动静脉血氧含量差C:(a一动q二caOZ一C、02和氧摄取率ERO:=（Ca02一价Olz）/C豆0乏。 3.记录术中失血量（根据吸引器中血量和估计纱布血量计算）、输液量和输血量。 （五）统计学处理， 所有数据用均数加减标准差（又士s）表示，组内比较用!t检验，组间比较用方差分析和q检验，P<0 .05为有显著性差异。实验结果 B、D组又时MAP明显低于术前;B组降压后HR显著增块;C、D组稀释后CVP显著增高，D组在降压期间CVP有所下降。B、D组术中失血量与A组比明显减少，C、D组术中的尿量明显多于A、B组。四组病人术后的Hb和Hct均明显低于术前，术后24小时D组Hb和Hct明显高于A组。四组病人术中pH值、乳酸、K‘、Na令、所心2、ERO:无显著差异。讨论 控制性降压用来减少术中失血已应用多年，单独应用时可能因血流缓慢而引起重要组织器官灌注不足，从而可导致脏器损伤。急性高容血液稀释与控制性降压联合应用可以取长补短，但实施的最大顾虑是容量过负荷有造成肺水肿的危险，以及是否会引起组织器官缺血缺氧。 AHH后容量负荷增高导致CVP的增高，增加了病人容量负荷过重的危险，用硝普钠扩血管后能够减轻容量负担过重，四组病人术后均无肺水肿和心衰等并发症的发生。此外，D组病人在整个术中除控制性降压时外，很少发生MAP和HR的骤然变化。因此，从维持血流动力学稳定上看，D组明显优于B、C组。 在手术更多还原

【Abstract】 IntroductionThe risk of associated with transfusion of homologous blood have provided the impetus for the development of techniques to minimize transfusion. Acute no-movolemic hemodilution (ANH) is a effective stalegy to decrease blood loss which has been estahlisted. But this technique requires a certain amount of extra time and effort,and it increase the dangers of infection. Therefore simplified the technique of AMH( acute normovolemic hemodilution) by hemodilution our patient with hydroxyethylstarch or crystalloid preoperatively without removing there autologous blood, resulting in acute hypervolemic hemodilution ( AHH). In the surgery, colloid solution was infusion ire a volume equal to blood loss. Loss of fluid from the open surgery field and the urine output was replaced by an equal volume of Ringer’s lactate. One of hemodilution method is transfused 15ml/kg hydroxyethistarch at the rate of 50ml/min before surgery. To prevent the hemo-dynamic effects of a large mtr&vascular volume ,we often used inhaled anesthetic , spinal or epidural block and vasodilator to induce controlled hypotension (CH). AHH combined with CH can decrease blood loss and the homologous blood transfusion has been demonstrated. But effect of AHH combined with CH on the balance of oxygen supply and need of tissues is still not clear. Lactate, mixed venous blood saturation ( SvO2 ) and oxygen extraction ratio ( ERO2 ) are the reliable variables to reflect the systemic oxygenation. Our study observe the hymodynamics when AHH combined with CH is performed in the sugery, measure the lactate,K+ ,Na+ ,Ca2+ and other variables of oxygen supply and need, to evaluate the safty and effectiveness of the combined application.Materialsinstrument: Belong intravenous infusion pump (German) ; Datex - Omeda 110 anesthesia machine ( USA); Hp monitor ( USA) ; Bayer blood gas analysis machine( USA) ; Qiangsheng auto chemical analysis machine 250(USA).medicine: 6% hydroxyethylstareh(HES, German); Isofliurane (USA,Ya-Pei) ; Nitroprusside (Beijing).MethodsPatient: we studied 48 patients from surgery of orthopedic department, ASA I - II , undergoing elective operation of hip replacement , spine surgery and femor fracture fixation, estimate the blood loss is about 1000ml. They have no cardiac, pulmonary ,hepatic and renal insufficiency,no hypertension or disease of system of hematologic, Hb > 12g/L and Hct > 35%. These 48 cases were divided into four groups of twelve randomly. A ,control group; B, controlled hypertension group; C , acute hypervolemic hemodilution group and D, AHH combined with CH group.Anesthesia method: all patient were given vallum 10mg ., po. and .atropine 0. 5mg,im. 30 minutes before operation. Induced by fentanyl 4ug/kg, midazo-lam 0. 4mg/kg, propofol 1.5 - ling/kg, vecuronium 0.1mg/kg, After trachea intubation the patient were ventilated mechanically with inspiration of Isoflurane (1 -3% ) and N2O/O, 1 ;1. Respiration rate was 12 bpm, tidal volume was 8 - 10ral/kg, vecuronium was intermittent iv. In the operation, right jungular venous puncture was used for monitor and taking; blood sample, radial artery was cannulated, Fury catheter was inserted for urine output, Ringer’s lactate 8 -10 ml/kg was infusion in all patients and loss of fluid and urine output was replaced by a equal volume of Ringers, colloid solution infused in a volume equal to blood loss. When Hb <75g/L, blood transfusion started.After intubation, the patient of group C and D infused 15ml/kg HES at the rate of 50ml/min, Group B and D induced hypotension by nitroprusside at 0.1- 2ug/min gradually reduce mean arterial blood pressure ( MAP) to decrease 30% of the baseline at the time of about 20 minutes after incision, when the sur-gon finished the major step, discontinued infusion.Index measurement:Monitor SBP, DBP, MAP, HR, SPO2, CVP, ECG, and urine output per hour continuously. At the time of before hemodilution(T0) , after hemodilution ( T1) , 1 h after hemodilution ( T2 ) , at the end of operation ( T3 ) , and 24 h after operation (更多还原