体外循环心脏直视手术中红细胞携氧能力的临床观察

目的　观察体外循环 (CPB)心脏直视手术中红细胞携氧能力的变化。方法　观察 1 5例择期心脏手术病人的红细胞形态、P5 0和红细胞内 2 ,3 二磷酸甘油酸 (2 ,3 DPG)的含量在围转流期的变化。结果　红细胞在CPB期间发生畸形变 ;红细胞内 2 ,3 DPG的浓度在CPB结束时较术前明显增加[(7 82± 1 5 5 ) μmol/ml对 (6 39± 1 2 7) μmol/ml,P <0 0 5 ];P5 0在转流前后无明显变化。 结论　尽管红细胞的形态在CPB期间有所改变 ,但其携氧能力变化不明显。     

体外循环中不同条件对乳酸脱氢酶活性和乳酸代谢影响的临床观察

CPB 手术病人16例,转流时间在90min 以内8例为 A 组,转流时间在90min 以上8例为 B组。观察了 CPB 中灌注流量、MAP、血液稀释度、温度对 LDH 活性和乳酸含量变化的影响。结果表明:转流后 10min、开放主动脉后2min、停 CPB 后2min 时 LDH 活性和乳酸含量均明显高于转流前,转流、阻断循环时间长者明显高于短者。     

浅低温体外循环冠脉搭桥手术中病人脑氧合的变化

心肺转流(CPB)体外循环心脏手术病人,术后中枢神经系统并发症高达2%～5%,其发生与脑栓塞及脑氧合失调有关。颈静脉球血氧饱和度可反映脑代谢的变化,常作为一种检测脑氧合平衡的指标[1]。因此我们观察了浅低温CPB冠脉搭桥手术中SjvO2及相关指标的变化,以探讨脑氧合的变化规律。1     

血管紧张素Ⅱ受体A1166C基因多态性对体外循环中血压的影响

目的 研究血管紧张素Ⅱ1型受体(AT1R)基因多态性对体外循环(CPB)术中转流平稳期病人动脉血压的影响。方法 详细记录82例病人CPB转流平稳期的平均动脉压(MAP)，放免法测定所有病人CPB前和CPB中血浆血管紧张素Ⅱ的浓度，用PCR-RFLP方法检测其ATIR基因型，根据突变与否分为突变组与正常组。结果 突变组7例，正常组75例。突变组病人观察期内MAP的平均值(MMAP)、最小值(Mini)和扩血管药的用量与正常组相比差异有显著性，其与血浆中血管紧张素Ⅱ的浓度无关。结论 AT1R基因多态性对CPB转流平稳期血压状态有明显影响，可能是CPB中某些情况下循环高灌注和CPB预后不良的原因之一。     

低温体外循环期间酸碱平衡的维持

心肺转流、中度低温是目前心脏手术最通用的方法。体外循环期间体内酸碱平衡的维持是保护心、脑的重要措施之一。为减轻降温及转流过程的酸中毒,我们对16例心脏直视术病人转机开始后静滴碱性药物目行血气监测,并对碱性药物应用的剂量、时间、方法等问题加以探讨。资料及方法一、一般资料 16例心脏直视术,女10例,男6例,年龄18～52岁,体重43～62kg。风心病瓣膜置换术     

体外循环期间尼莫地平对脑糖代谢的影响

目的　研究体外循环 ( CPB)中尼莫地平对脑糖代谢的影响。方法　选择 3 1例心脏直视手术病人 ,随机分为对照组 11例 ,观察组 2 0例。尼莫地平 4 0μg· kg- 1 于 CPB始缓慢注入体外循环机中 ,测定不同时期两组病人的动脉、颈内静脉上球部的血糖、丙酮酸、乳酸和乳酸脱氢酶 ( L DH) ,计算出脑糖摄取 GL U( a- v)、乳酸净剩余 ( L v- a)值。结果　 CPB过程中两组动脉、颈内静脉上球部的血糖、丙酮酸、乳酸和 L DH均进行性升高 ,两组 GL U( a- v)均低于 CPB前 ,但观察组明显高于对照组 ,两组L v- a无显著差异。结论　 CPB中尼莫地平明显提高脑糖利用 ,产生较多的能量以维持脑细胞功能的正常     

7262例体外循环管理经验总结

目的总结体外循环(CPB)管理的经验及教训,为更安全的CPB方式提供参考。方法回顾性分析我院1964年2月~2004年12月施行的CPB心内直视手术7 262例患者的临床资料,并对硬件设备、转流技术、灌注师经验、术中监测及心肌保护等方面进行分析,其中3 748例患者采用心脏不停跳CPB。结果全组死亡248例,总死亡率3.4%(248/7 262)。1964年2月~1983年12月施行CPB手术464例,死亡52例,死亡率11.2%;1984年1月~1996年12月施行CPB手术1 709例,死亡78例,死亡率4.6%;1997年1月~2004年12月施行CPB手术5 089例,死亡118例,死亡率2.3%;1997年3月~2004年12月,对3 748例患者采用心脏不停跳CPB,手术顺利,未发生与CPB相关的并发症及死亡。结论灌注师的经验和硬件设备的完善、使用高质量的人工心肺机和氧合器、多种转流技术的应用、完善的监测系统等可明显提高CPB的安全性。心脏不停跳下CPB是安全且易于管理的一种方式。     

止血芳酸对体外循环中血栓素A2、前列腺环素的影响

目的 通过观察止血芳酸（PAMBA）对体外循环（CPB）心脏手术中血栓素A2（TXA2）、前列腺环素（PGI2）对影响，探讨其对CPB中血小板功能的保护作用。方法 40例择期CPB心脏手术病人，随机分为两组（每组20例），观察组（A组）于CPB前、CPB预充液中以及鱼精蛋白中和后10min，经中心静脉分别给予PAMBA250mg；对照组（B组）分别给予等容量的生理盐水。分别在切皮前、CPB开始后30min、CPB停机及手术结束时检测血小板计数，采用ELISA法测定血浆TXB2和6－keto-PGF1α的浓度。结果 CPB前两组血小板计数无明显差异。转流后两组各时点和基础值相比显著下降（P＜0.01)，但A组和B组相比血小板计数降低程度明显减轻（P＜0.05)；B组TXB2明显升高，6-keto-PGF1α与转流前比较有所升高，TXB2／6-keto-PGF1α比值明显升高；观察组TXB2的增加及TXB2／6-keto-PGF1α比值明显低于对照组（P＜0.01)，而6-keto-PGF1α的增加则明显高于对照组（P＜0.05)。结论 CPB前和CPB中给予PAMBA有利于维持TXA2和PGI2在体内的平衡，从而在一定程度上保护了血小板的功能，显著减少了CPB和术后非外科性出血。     

体外循环期间脑氧供需情况的观察

目的与方法 :通过对 2 0例心脏瓣膜置换术患者在体外循环心肺转流 (CPB)手术中行动脉和颈内静脉血气监测 ,以了解CPB期间脑氧供需情况。结果 :(1)降温期颈内静脉血氧饱和度 (SjvO2 )和脑血流量 /脑氧耗代谢比(CBF/CMRO2 )明显增加 ,由 6 6 2 4%± 10 32 % ,17 91± 3 0 4增至 93 81± 3 86 % ;139 2 8± 13 2 5。 (2 )复温期SjvO2和CBF/CMRO2 明显回落 ,分别降至 70 2 3%± 6 2 9% ,2 1 44± 9 6 8。 (3)CBF/CMRO2 与鼻咽部温度 (NPT)呈负相关 ,r =- 0 789。结论 :CPB中降温期可产生灌注过剩 ,复温过程可出现脑灌注不足     

体外循环对血管内皮细胞损伤/活化的临床研究

目的 研究体外循环（ＣＰＢ）对全身性血管内皮细胞（ＶＥＣ）的急性损伤／活化。方法２６例心血管择期手术病人,分为两组,１４例先心病心内畸形矫治术患者为Ｉ期,１２例心脏瓣膜替换术患者为Ⅱ组。于术前、转流前、转流后３０ｍｉｎ、停转流、手术结束、术后１ｄ和术后３ｄ采血动态监测两组病人循环内皮细胞（ＣＥＣ）、血浆血栓调节蛋白（ＴＭ）和冯维尔布兰德因子（ｖＷＦ）的变化。结果 两组病人血ＣＦＣ、血浆ＴＭ和ｖＷＦ     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.