婴幼儿体外循环对红细胞内钙离子浓度的影响

目的 通过比较先天性心脏病患儿体外循环(cardiepulmonary bypass,CPB)过程中红细胞内外钙离子浓度的变化,探讨CPB对红细胞形态和功能的影响.方法 分别于CPB前、中、后抽取26例先天性心脏病患儿的中心静脉血检测血浆游离钙离子浓度,同时采用Fluo-3-AM测定红细胞内的钙离子浓度.结果 CPB中血浆钙离子浓度由CPB前的(1.24±0.06)mmol/L降低至(0.99±0.05)mmol/L,CPB后钙离子浓度又恢复至(1.28±0.08)mmol/L;CPB过程中红细胞内钙离子浓度则维持了相对稳定[CPB前(138±72)nmol/L;CPB中(145±70)nmol/L;CPB后(115±83)nmol/L].结论 CPB期间红细胞内钙离子浓度无显著变化.     

心肺转流控制动脉氧分压对心脏瓣膜置换术患者红细胞免疫功能的影响

目的通过观察心肺转流(CPB)中控制动脉氧分压(PaO2)对心脏瓣膜置换术患者红细胞免疫功能及脂质过氧化损伤的影响,探讨其对红细胞的保护作用。方法选择20例择期行心脏瓣膜置换术患者,随机均分为两组,控制PaO2组(Ⅰ组,PaO2100～250mmHg)和高PaO2组(Ⅱ组,PaO2350～450mmHg)。入手术室后行桡动脉、中心静脉穿刺,气管插管全身麻醉后建立CPB,CPB后通过调节吸入氧浓度调节控制PaO2。两组均在麻醉前(T1)、CPB前(T2)、CPB后15min(T3)、主动脉开放15min(T4)、术后24h(T5)抽动脉血分别作酵母菌花环试验、检测红细胞内丙二醛(MDA)含量,血浆游离血红蛋白(PF-Hb)及血浆MDA含量。结果与T1时比较,T3～T5时两组RBC-C3bRR明显降低、RBC-ICRR明显升高(P<0.05);T2～T5时两组PF-Hb明显升高(P<0.05)。与Ⅰ组比较,T4、T5时Ⅱ组RBC-ICRR明显降低(P<0.05);T3～T5时Ⅱ组PF-Hb、红细胞MAD含量和T3、T4时血浆内MAD含量明显升高(P<0.05)。结论 CPB可导致损伤及免疫功能下降,CPB中控制PaO2可减轻红细胞的脂质过氧化损伤,减轻对红细胞的免疫功能的损伤,对CPB中的红细胞有较好的保护作用。     

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。     

新型白细胞滤器LD-1对体外循环中红细胞的保护作用

目的研究一种新型白细胞滤器LD-1在体外循环(CPB)中对红细胞的保护作用。方法将25～30kg蒙古犬12只按随机数字表法分为对照组和LD-1过滤组(LD组),每组6只。对照组不使用白细胞滤器;LD组将白细胞滤器LD-1安装于CPB的静脉回流端,在CPB开始2min后打开滤器,过滤5min。分别于CPB前、CPB10min、40min、75min、停CPB和CPB后2h取静脉血测定白细胞(WBC)数量、血浆丙二醛(MDA)、超氧化物歧化酶(SOD)和游离血红蛋白(FHB)水平,并测定红细胞脆性。结果在CPB中各时间点LD组WBC数量均显著低于CPB前(P<0.01),且明显低于对照组(P<0.05);对照组血浆SOD水平在CPB75min后显著降低,而LD组血浆SOD水平在CPB75min、停CPB及CPB后2h均显著高于对照组(P<0.05,0.01);在CPB后各时间点LD组MDA水平均低于对照组,但无统计学意义;对照组在停CPB和CPB后2h,红细胞开始溶血和完全溶血所需的氯化钠浓度明显高于LD组(P<0.05);CPB后两组血浆FHB浓度均升高(P<0.01),但LD组在CPB40min后各时点均显著低于对照组(P<0.05)。结论新型白细胞滤器LD-1在CPB中能有效去除白细胞,保存血浆的抗氧化能力,抑制氧自由基对红细胞的破坏。     

心肺转流不同氧分压对红细胞衰变加速因子的影响

目的 探讨心肺转流(CPB)中不同动脉氧分压(PaO2)对红细胞衰变加速因子(DAF或CD55)的影响.方法 40例心脏病患者随机均分为四组:紫绀型先天性心脏病高氧分压组(A组)及正常氧分压组(B组),非紫绀型心脏病高氧分压组(C组)及正常氧分压组(D组).CPB中,A、C组PaO2控制在300～500 mm Hg,B、D组PaO2控制在100～250 mm Hg.于CPB前(T1)、CPB15 min(T2)、主动脉开放15 min(T3)、术后24 h(T4)采集动脉血,用小鼠抗人CD55 FITC荧光单克隆抗体直接标记,流式细胞仪检测红细胞CD55活性及数量.结果 A组T2、T3时的红细胞CD55活性明显高于T1时(P<0.05).但红细胞CD55数量差异无统计学意义.B、C、D三组各时点红细胞CD55活性及数量差异无统计学意义.结论 CPB中高氧分压可使紫绀型心脏病患者的红细胞CD55活性明显增强,缺氧红细胞可能存在再氧合损伤;控制氧分压对红细胞免疫功能有一定的保护作用.     

库存悬浮红细胞预处理对婴幼儿预充液中血糖、乳酸及钾离子的影响

目的 观察库存悬浮红细胞预处理后对婴幼儿预充液中血糖、乳酸及钾离子浓度的影响,及对婴幼儿生理代谢的影响. 方法 2010年2月至201 1年3月解放军第452医院收治40例先天性心脏病婴幼儿,按预充前是否清洗库存悬浮红细胞,将其分为两组,悬浮红细胞清洗组(清洗组,n=20):男11例,女9例；年龄(17.82±6.11)个月；在体外循环(CPB)中预充前采用血液回收机(cell saver)对库存悬浮红细胞进行清洗预处理；未清洗组(n=20):男6例,女14例；年龄(16.63±4.45)个月；在应用库存悬浮红细胞预充前未经清洗.两组在预充前(清洗组在库存悬浮红细胞清洗前、清洗后)、预充后、CPB前并行期、主动脉阻断后5 min、停机时分别检测血糖、血清乳酸和血钾离子浓度. 结果 清洗组库存悬浮红细胞清洗后血糖、乳酸和钾离子浓度明显低于清洗前(P＜0.05).在CPB各时间点清洗组血糖[主动脉阻断后5min:(4.50±0.65) mmol/L vs.(5.78±0.62)mmol/L,t=5.308,P=0.001]和乳酸浓度[主动脉阻断后5min:(1.86±0.21) mmol/L vs.(2.89±0.45) mmol/L,t=1.504,P=0.001]明显低于未清洗组.除停机时,其余时间点清洗组钾离子浓度明显低于未清洗组[主动脉阻断后5 min:(3.81±0.32) mmol/L vs.(4.44±0.51)mmol/L,F3.588,P=0.011]. 结论 采用血液回收机(cell saver)清洗后的含库存悬浮红细胞预充液中的血糖、乳酸、钾离子浓度明显降低至生理范围内,可显著提高婴幼儿CPB的安全性.     

血小板获得性损害与体外循环出血并发症

许多因素可以引起病人CPB术后出血,大量文献报道CPB过程导致机体出、凝血功能紊乱引起CPB术后出血。本文就CPB过程引起的血小板获得性损害导致CPB术后出血的原因、机制及抑肽酶治疗加以综述。     

改良超滤对婴幼儿心内直视术后血液流变学的影响

目的评估改良超滤(MU F)对婴幼儿心内直视术后血液流变学的影响。方法选取需行手术治疗、体重<10kg的室间隔缺损(V SD)合并肺动脉高压(PH)患者22例,按住院号的奇、偶数分为对照组(10例,尾数为奇数者)和实验组(12例,尾数为偶数者)。对照组体外循环(CPB)结束后不行MU F,实验组于CPB停机后行MU F,超滤时间10~15m in,超滤流量10~15m l/m in.kg。分别于术前、CPB停机时、CPB后15m in/MU F结束时、术后2h和24h 5个时间点采集桡动脉血2.5m l,采用M DK-3200双通道全自动血液流变测试分析仪检测血液流变学相关指标的变化。结果实验组MU F结束时血红蛋白、红细胞压积、红细胞计数、屈服应力、血浆粘度、全血高切粘度、全血中切粘度、全血低切粘度、全血高切还原粘度、全血中切还原粘度、全血低切还原粘度和卡松粘度均较对照组CPB后15m in明显升高(P<0.05);红细胞变形指数、红细胞聚集指数各时间点两组间比较差异均无统计学意义(P>0.05)。结论使用MU F可明显提高CPB后患者的血红蛋白、红细胞压积、红细胞计数,婴幼儿CPB后采用MU F,其血液粘度高于未行MU F患者。     

平衡超滤法与改良超滤法的应用比较

目的　比较平衡超滤法和改良超滤法在小儿心肺转流术 (CPB)中使用的效果。　方法　 40例先天性心脏病患者 ,随机分成两组 :平衡超滤组 (BU F组 )和改良超滤组 (MU F组 ) ,分别在整个 CPB期间和停 CPB后进行超滤。结果　 BUF组在 CPB中滤出液体 815 .0± 30 0 .9ml,MU F组滤出液体 394.4± 81.4ml;BUF组在 CPB过程中炎症因子的浓度无明显变化 ,而 MUF组则有上升趋势 ,CPB结束时 BUF组炎症因子浓度明显低于 MUF组 (P<0 .0 5 ) ;MUF组进行超滤时 ,红细胞压积明显提高 ,炎症因子浓度有所上升。　结论　平衡超滤法能在 CPB中维持较低的体内炎症介质浓度 ,改良超滤法可以在术后迅速浓缩血液 ,但对降低炎症介质的浓度影响较小。     

丙泊酚对心肺转流下心内直视手术患儿红细胞膜ATP酶的影响

目的 观察不同剂量丙泊酚对心肺转流（CPB）下心内直视手术患儿红细胞脂质过氧化反应及红细胞膜ATP酶活性的影响。方法 60例于CPB下行房（室）间隔缺损修补术的先天性心脏病患儿,随机均分为小剂量丙泊酚组（LP组）、大剂量丙泊酚组（HP组）和对照组（C组）。LP组给予丙泊酚3mg·kg^1·h^-1泵入,HP组给予丙泊酚8mg·kg^-1·h^-1泵入。分别于CPB前（T1）、CPB10min（T2）、主动脉开放10min（Ts）、20min（Tt）、术毕（Ts）、术后24h（Ts）抽取动脉血,测定血浆脂质过氧化物（LPO）、血浆丙二醛（MDA）、红细胞LPO、红细胞MDA水平和红细胞超氧化物歧化酶（SOD）、红细胞膜NatKtATP酶及Ca^2＋Mg^2＋-ATP酶活性。结果各组CPB后血浆LPO、MDA和红细胞LPO、MDA水平较CPB前明显升高（P〈0．05）,主动脉开放后红细胞SOD、Na^＋-KtATP酶、Ca^2＋Mg^2＋-ATP酶活性明显降低（P〈0．05）。HP组各时点血浆LPO、MDA和红细胞LP0、MDA水平较C组低（P〈0．05）,红细胞s0D、Na^＋-K^＋-ATP酶、Ca^2＋Mg^2＋-ATP酶活性较C组高（P〈0．05）,LP组与C组比较差异无统计学意义。结论 CPB期间,大剂量丙泊酚通过减轻红细胞脂质过氧化反应,对小儿红细胞膜ATP酶起到一定的保护作用。     

Cardiopulmonary bypass in humans--jejunal mucosal perfusion increases in parallel with well-maintained microvascular hematocrit

BACKGROUND: An imbalance between splanchnic oxygen supply and demand occurs during cardiopulmonary bypass (CPB) in man, which might disrupt the intestinal mucosal barrier function. The aim of the present study was to evaluate the effects of mild hypothermic CPB on intestinal mucosal perfusion in man undergoing cardiac surgery. Additionally we aimed to identify variables, which independently could predict changes of intestinal mucosal microcirculatory variables during CPB. METHODS: Jejunal mucosal perfusion (JMP), jejunal mucosal hematocrit (JMHt), red blood cell (RBC) velocity and arteriolar vasomotion using endoluminal jejunal laser Doppler flow metry were studied in eight cardiac surgical patients before and during CPB at a temperature of 34 degrees C. RESULTS: Cardiopulmonary bypass and the accompanied hemodilution (25-30%) induced a 44% increase in JMP (P < 0.05) and a 42% increase in RBC velocity (P < 0.01), with no change in JMHt. The oscillation amplitude of JMP, at a fundamental frequency of 2.8 cycles min(-1), increased with 175% (P < 0.05) during CPB. Splanchnic oxygen extraction increased by 64% during CPB (P < 0.05). Stepwise multiple regression analysis identified systemic hematocrit, arterial O2 and CO2 tension and splanchnic oxygen extraction as independent predictors of RBC velocity during CPB (R2=0.63, P < 0.001). The oscillation amplitude of JMP was predicted by RBC velocity and splanchnic oxygen extraction (R2= 0.68, P <0.0001). CONCLUSIONS: The increase in RBC velocity and enhanced arteriolar vasomotion, as well as maintained jejunal mucosal hematocrit, are microcirculatory, compensatory mechanisms for the splanchic oxygen supply/demand mismatch seen during cardiopulmonary bypass in humans.     

A comparative study of prostacyclin infusion given before and during cardiopulmonary bypass to assess the first pass effect of the circuit on platelet number and function

Platelet damage during cardiopulmonary bypass (CPB), although proportional to the duration of bypass, may result in significant dysfunction after the initial contact with an extracorporeal circuit, the so-called 'first pass' phenomenon. The platelet sparing effect of prostacyclin (PGI2) infusion was studied in a double-blind randomized trial on male patients undergoing coronary artery bypass grafts to assess the effect of the 'first pass' through the CPB circuit. Prostacyclin infusion was begun before the onset of CPB or during CPB in two groups which were compared to a placebo control group. A standardized anaesthetic, surgical and perfusion technique were used. Preoperatively and during surgery at pre-set intervals, whole blood platelet aggregation was studied using ADP and collagen agonists. Platelet numbers and function measured by ADP aggregation were conserved in the two PGI2 groups. There was no significant difference between the treated groups. We conclude, therefore, that the initial contact of platelets with the CPB circuit, in the absence of PGI2 did not irreversibly affect platelet function. In addition, the hypotensive action of PGI2 was easier to control once on bypass. It may therefore be preferable to delay PGI2 infusion until CPB has been established.     

Sevoflurane but not propofol preserves myocardial function in coronary surgery patients

BACKGROUND: Sevoflurane has been shown to protect against myocardial ischemia and reperfusion injury in animals. The present study investigated whether these effects were clinically relevant and would protect left ventricular (LV) function during coronary surgery. METHODS: Twenty coronary surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhalational anesthesia with sevoflurane. Except for this, anesthetic and surgical management was the same in all patients. A high-fidelity pressure catheter was positioned in the left ventricle and the left atrium. LV response to increased cardiac load, obtained by leg elevation, was assessed before and after cardiopulmonary bypass (CPB). Effects on contraction were evaluated by analysis of changes in dP/dt(max). Effects on relaxation were assessed by analysis of the load dependence of myocardial relaxation (R = slope of the relation between time constant tau of isovolumic relaxation and end-systolic pressure). Postoperative concentrations of cardiac troponin I were followed during 36 h. RESULTS: Before CPB, leg elevation slightly increased dP/dt(max) in the sevoflurane group (5 +/- 3%), whereas it remained unchanged in the propofol group (1 +/- 6%). After CPB, leg elevation resulted in a decrease in dP/dt(max) in the propofol group (-5 +/- 4%), whereas the response in the sevoflurane group was comparable to the response before CPB (5 +/- 4%). Load dependence of LV pressure fall (R) was similar in both groups before CPB. After CPB, R was increased in the propofol group but not in the sevoflurane group. Troponin I concentrations were significantly lower in the sevoflurane than in the propofol group. CONCLUSIONS: Sevoflurane preserved LV function after CPB with less evidence of myocardial damage in the first 36 h postoperatively. These data suggest a cardioprotective effect of sevoflurane during coronary artery surgery.     

Red blood cell age, pyruvate kinase activity, and insulin receptors. Evidence that monocytes and RBCs may behave differently

Data emerging from insulin receptor studies performed on red blood cells (RBCs) and monocytes from the same subject are not always in agreement; dichotomy might occur since variations in mean RBC age are not taken into account or because insulin receptors on the two cell types behave differently. In the present investigation RBCs from normal male subjects were separated into five populations of different mean age by means of centrifugation of RBCs on a discontinuous gradient of buffered Percoll for 10 min at 1000 X g. Insulin binding varied significantly depending upon the RBC population tested and was closely correlated to the activity of pyruvate kinase (r2 = 0.86), a well-known marker of RBC age. These data suggested that pyruvate kinase assay might be helpful in studies of RBCs. To confirm this hypothesis, RBCs from 10 normal male subjects and 13 male patients with hemolytic anemia were studied; insulin binding was correlated to pyruvate kinase activity. By adjusting insulin binding to 2 X 10(9) RBCs/ml the range of data was abnormally high, but it became acceptable after adjusting insulin binding to pyruvate kinase activity (0.75 U/2 X 10(9) RBCs). The overall data indicated that insulin binding was highly correlated to pyruvate kinase activity (r2 = 0.82) but only slightly to reticulocyte number (r2 = 0.56) since not only reticulocytes but also erythrocytes lose receptors during maturation. Pyruvate kinase activity was measured in RBCs from normal men and from normally menstruating women at the seventh and twenty-fourth days of the cycle; results demonstrated that adjustment of data, according to mean RBC age, broadens dichotomy of monocyte and RBC data.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pyruvate prevents poly-ADP ribose polymerase (PARP) activation,oxidative damage,and pyruvate dehydrogenase deactivation during hemorrhagic shock in swine

The inadequate availability of fuel substrates and sharp decline in cellular ATP have been implicated in a cascade of events associated with cell death and organ failure during hemorrhagic shock (HS). In this in vivo swine model of severe prolonged HS, the effect of exogenous pyruvate administration on various markers of cell damage in brain and liver was examined. Thirty minutes after the start of controlled arterial hemorrhage, 30% sodium pyruvate, 10% saline, or 0.9% saline was administered via jugular vein. Four hours after the initiation of hemorrhage, tissue samples from brain and liver were obtained and examined for the cellular and molecular markers of cellular damage. Results of our study suggest that pyruvate prevents loss of total NAD content, cleavage of poly-ADP ribose polymerase (PARP), and inhibits lipid peroxidation in both the brain and liver of swine during prolonged severe HS. We conclude that there are multiple mechanisms by which pyruvate can possibly prevent cell damage caused during HS.     

心脏手术围术期红细胞内三磷酸腺苷含量变化

目的对体外循环心脏手术患者术中及术后３天红细胞（ｒｅｄｂｌｏｏｄｃｅｌ，ＲＢＣ）内三磷酸腺苷（ａｄｅｎｏｓｉｎｅｔｒｉｐｈｏｓｐｈａｔｅ，ＡＴＰ）含量进行动态观察。方法１５例心脏手术患者分别于麻醉诱导前、锯胸骨、体外心肺转流建立、主动脉阻断５分钟、转流结束、手术结束、术后第１天、术后第２天和术后第３天９个时间点取动脉血，测定ＲＢＣ内ＡＴＰ含量。结果手术期间ＲＢＣ内ＡＴＰ含量呈升高趋势，于手术结束达最高点，术后３天明显下降。结论麻醉、体外循环及手术对ＲＢＣ能量代谢具有一定影响     

双歧三联活菌预处理对体外循环后大鼠肠黏膜屏障功能的影响

目的 探讨双歧三联活菌预处理对体外循环(CPB)后大鼠小肠黏膜屏障功能的影响.方法 成年雄性SD大鼠24只,体重350～450 g,随机分为3组(n=8):假手术组(S组)、CPB组和双歧三联活菌预处理组(P组).CPB开始前7 d,P组每天用双歧三联活菌2 ml(含活菌数1×10~7 CFO)灌胃,S组和CPB组用生理盐水2 ml灌胃.第8天进行CPB 60 min.CPB结束后2 h时处死大鼠,抽取门静脉血,采用分光光度法测定血浆二胺氧化酶活性和D-乳酸浓度,鲎试验偶氮显色法测定内毒素浓度,放免法测定血浆TNF-α和IL-6的浓度.取腔静脉血,肝、肺、肾组织及肠系膜淋巴结,分别接种于血平皿上培养,24 h后鉴定细菌生长情况及细菌种类,光镜下观察小肠上皮组织病理学.结果 与S组相比,CPB组和P组血浆D-乳酸、内毒素、TNF-α和IL-6的浓度、二胺氧化酶活性及细菌易位率升高(P<0.05);与CPB组相比,P组上述各指标降低(P<0.05).病理结果显示P组小肠上皮组织损伤程度较CPB组明显减轻.结论 双歧三联活菌预处理可在一定程度上抑制炎性反应,保护CPB后大鼠小肠黏膜屏障功能.     

Thromboxane A2 receptor blockade improves contractile function following cardiopulmonary bypass in dogs and pigs.

Thromboxane A2/prostaglandin endoperoxide (TP) receptor antagonists have been reported to decrease the extent of myocardial damage after coronary ligation. The purpose of this study was to determine if the TP antagonist SQ 30,741 can protect myocardial tissue during cardiac arrest and cardiopulmonary bypass (CPB) in dogs and pigs. In the first part of the study, anesthetized dogs were subjected to normothermic CPB (37.5 degrees C) at a flow rate of 2 liters/m2/min. Dogs were treated with either 5 mg/kg + 5 mg/kg/hr SQ 30,741 or vehicle starting before CPB. The aorta was cross-clamped for 25 min and then released to allow reperfusion. In another study, pigs had hypothermic (28 degrees C) CPB but with arrest for 1 hr. Myocardial recovery was assessed by segment shortening as determined by sonomicrometry. Canine hearts treated with SQ 30,741 had a significantly improved reperfusion contractile function such that at 60 min postreperfusion, segmental shortening returned to 96% of pre-bypass levels vs 70% in vehicle-treated controls (P less than 0.05). In pigs, 70% of vehicle-treated pigs could not be weaned off CPB and died. All six pigs treated with SQ 30,741 survived. SQ 30,741 prevented platelet loss in dogs, but did not in pigs. Thus, SQ 30,741 significantly improved reperfusion function in hearts subjected to CPB.     

毛细血管渗漏综合征中内皮祖细胞的作用

体外循环后毛细血管渗漏综合征的血管修复对该病的恢复起到至关重要的作用。外周血中存在着能分化为血管内皮细胞的内皮祖细胞,能够促进损伤血管修复和生后血管再生。血浆中的血管内皮生长因子（VEGF）、促红细胞生成素（EPO）等因子通过刺激血管内皮祖细胞的动员、迁移、黏附和分化,促进血管修复和再生。现对体外循环后血管内皮祖细胞的数量和功能情况及其与血浆相关因子的相互作用进行综述,旨在为毛细血管渗漏综合征的治疗和预防提供新的思路.     

围体外循环期红细胞免疫功能的变化

观察先心病病儿在围体外循环期红细胞膜表面补体Ｃ３ｂ受体和膜流动性的变化。方法：随机选择２０例病儿在７个不同时点中心静脉取血，ＥＬＩＳＡ法测定ＲＢＣ－ＣＲ１表达量，荧光偏振法测ＲＢＣ膜流动性，生化法测全血ＧＳＨ－Ｐｘ和ＲＢＣ－ＧＳＨ含量。