透析液碳酸氢根浓度对透析中血清钾离子浓度的影响

目的 分析使用不同碳酸氢根(HCO3)浓度透析液对慢性维持性血液透析患者透析过程中血清钾离子(K+)浓度下降程度的血液动力学影响.方法 8例稳定血液透析患者进入临床试验,采取双盲、随机、3阶段、交叉对照的设计方案,透析液碳酸氢根浓度制定为:低浓度透析液(LB,27mmol/L)、标准浓度透析液(SB,35 mmol/L)、高浓度透析液(HB,39 mmol/L),每次透析过程血流量均为300 ml/min,透析液流量为500 ml/min,分别在0(基础值)、15、30、60和240 min从透析管路动脉端留取血标本做血液生化检测和血气分析.对血液透析后1 h的血清K+浓度以及通过透析K+的清除量进行检测.每例患者完成3次检测,每次试验检测过程中有1周的实验间期.结果 在低浓度透析液组(LB组),K+浓度从[(5.4±0.26)mmol/L,基础值在15、30、60和240min时分别下降至(4.89±0.25)mmol/L、(4.89±0.22)mmol/L、(4.54±0.25)mmol/L和(4.26±0.44)mmol/L;在标准浓度透析液组(SB组),K+浓度从[(5.38±0.29),基础值]mmo/L在15、30、60和240min时分别下降至(4.89±0.24)mmol/L、(4.43±0.22)mmol/L、(4.08±0.23)mmol/L和(3.90±0.30)mmol/L;在高浓度透析液组(HB组),K+浓度从[(5.38±0.23)mmol/L,基础值在15、30、60和240 min时分别下降至(4.71±0.38)mmol/L、(4.38±0.33)mmol/L、(3.72±0.34)mmol/L和(3.32±0.16)mmol/L,其中高浓度与低浓度和标准浓度(HCO3)在60和240 min时点比较差异有统计学意义(P＜0.05);除了LB组,其他两组中血清K+浓度和HCO3比较差异有统计学意义(P＜0.05);对于LB组、SB组和HB组透析液,血清K+浓度的反弹率分别为(4.0±9.2)%、(5.2±3.2)%、(7.2±3.4)%.每次透析K+的清除量LB组为119.5±22.6(mmol/L)、SB组为85.5±14.9(mmol/L)、HB组为95.6±15.5(mmol/L).结论 高浓度透析液与在透析过程中血清K+的快速清除相关,该清除过程是因为加强了K+从细胞外移至细胞内的过程,而不是通过透析本身对K+的清除.     

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.     

复方醋酸钠在心肺转流心脏瓣膜置换术中对血乳酸和血糖的影响

目的 观察复方醋酸钠溶液在心肺转流(CPB)心脏瓣膜置换术中对血乳酸(Lac)、血糖(Glu)及血钾(K+)浓度的影响.方法 择期行CPB心脏瓣膜置换术患者40例,随机均分为复方乳酸钠组(R组)和复方醋酸钠组(L组).于CPB开始前(T0)、CPB开始后15 min(T1)、升主动脉开放前5 min(T2)、CPB结束前5 min(T3)和关胸后(T4)抽取动脉血或CPB机管路动脉端血液,检测Lac、Glu、K+浓度.结果 L组Lac浓度在T1～T4时均显著低于R组(P＜0.05);L组Glu浓度仅在T1时点明显高于R组(P＜0.05);两组各时点血K+差异无统计学意义.结论 心脏瓣膜置换术中,用复方醋酸钠作CPB晶体稀释液可降低术中Lac浓度的升高.     

连续动脉血乳酸水平与先天性心脏病手术预后的关系

目的探讨连续动脉血乳酸值与先天性心脏病患者体外循环(CPB)手术预后的关系。方法连续选择2006年3～9月接受CPB心内直视手术先天性心脏病患者551例,根据术后恢复情况将其分为死亡组(n=14)和生存组(n=537),再根据术后乳酸变化情况将生存组分为正常恢复组(n=513)和治疗恢复组(n=24,术后乳酸升高经治疗后恢复正常)。于CPB结束后0～1h、1～2h、2～3h、3～6h、6～9h、9～12h、12～18h、18～24h等时间段测定动脉血乳酸值;采用Spearman秩相关分析CPB结束后各时间段血乳酸值与死亡的关系。结果死亡组动脉血乳酸值在CPB结束后0～1h为4.46±2.78mmol/L,在其后各时间段内逐渐上升,至18～24h时达9.65±5.47mmol/L。而术后正常恢复组在CPB结束后0～1h内为2.80±0.90mmol/L,在1～2h内开始下降,至2～3h恢复到2.00mmol/L左右,并维持稳定。治疗恢复组在CPB结束后0～1h内为2.93±0.59mmol/L,并在2～3h持续上升,到9～12h达峰值(6.34±1.85mmol/L)后迅速下降,于18～24h恢复到2.14mmol/L左右。CPB结束后0～1h时间段的血乳酸值与死亡相关性最差(r=0.103,P=0.103),而其后各时间段与死亡事件呈高度的相关性(P=0.000)。结论连续动脉血乳酸测定可以对先天性心脏病患者CPB手术预后作出有效评估,持续血乳酸值上升是预测术后死亡的有效指标。     

含血预充液超滤技术在婴儿心脏手术中的应用

目的探讨体外循环(CPB)手术中含血预充液进行超滤洗涤后是否能使预充液达到生理状态,以及该方法对患者围术期电解质、酸碱平衡和心肺功能的影响。方法选取2009年2月至2009年6月在复旦大学附属儿科医院施行先天性心脏病手术治疗的40例患者,随机分为两组,实验组(n=20):男12例,女8例;年龄131.00±103.00 d,体重4.14±0.96 kg;术前利用CPB管道中血液超滤器对含血预充液进行超滤洗涤20 min。对照组(n=20):男11例,女9例;年龄127.00±88.00 d,体重4.38±1.05 kg;预充液在CPB管道中循环20 min。测定含血预充液洗涤前、后和患者围术期血气分析和电解质等指标;用超声心动图检测心功能指标包括短轴缩短率(FS),射血分数(EF)和心排血量(CO);观察肺功能变化。结果两组患者无死亡,均顺利出院。实验组呼吸机辅助呼吸时间显著短于对照组(2.7±0.3 d vs.4.1±0.4 d,P0.05)。实验组含血预充液经洗涤超滤后的各项指标均达到正常值范围,pH值升高(从6.89±0.22升至7.40±0.57,P=0.001),BE值升高(从-16.12±0.98 mmol/L上升至+0.31±2.40 mmol/L,P=0.000),钾离子浓度降低(从10.33±2.13 mmol/L降至4.27±0.93 mmol/L,P=0.000);白细胞介素-8浓度降低(从78.40±6.10 pg/ml下降至64.30±48.10 pg/ml,P=0.036);缓激肽浓度降低(从5 982±1 353pg/ml下降至531.00±35.00 pg/ml,P=0.031)。实验组FS、EF和CO术后下降幅度均小于对照组,术后4 h实验组CO显著高于对照组(2.77±0.95 L/min vs.1.66±0.75 L/min,P=0.001);术后24 h实验组EF高于对照组(67.44%±6.89%vs.61.17%±9.02%,P=0.003)。术后6 h两组肺泡-动脉血氧分压差(A-aDO2)和呼吸指数(RI)显著上升(P0.05),然后开始逐渐下降恢复至术前水平。实验组趋向于更早开始恢复肺功能。术后48 h,实验组A-aDO2和RI明显低于对照组(P0.05)。结论对含血预充液进行洗涤超滤可使CPB预充液更符合生理状态,减少炎性介质,改善婴幼儿术后心肺功能,这对新生儿和小婴儿进行复杂先天性心脏病手术时显得尤其重要。     

入肝血流阻断对肝切除术后血乳酸水平的影响

目的 分析肝切除术中入肝血流阻断对术后动脉血乳酸水平及pH值的影响.方法 回顾性分析我科2006年1月至2008年12月行肝切除术的68例患者,根据术中是否行人肝血流阻断分为肝门阻断组(20例)、规则半肝切除组(22例)和未阻断肝门组(26例).比较3组患者术后动脉血气、乳酸浓度及肝、肾功能等指标.结果 肝门阻断组和规则半肝切除组患者术后动脉血乳酸浓度明显升高[(5.53±2.31)mmoL/L,(5.62±2.52)mmol/L),与术中未阻断肝门组[(3.37±1.56)mmol/L]比较差异均有统计学意义(P<0.05);半肝切除组HCO3-水平较肝门不阻断组明显降低[(19.68±3.82)mmoL/L vs(21.65±2.48)mmol/L,P<0.05];3组患者术后的pH、肝肾功能等改变无统计学意义.结论 人肝血流阻断可导致肝切除术后动脉血乳酸水平明显增高,术后密切监测乳酸浓度并及时处理,可避免术后高乳酸血症及代谢性酸中毒.     

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.     

不同体位对经尿道前列腺等离子双极电切术患者术中冲洗液吸收的影响

目的:观察头低足高截石体位(LP)对接受经尿道前列腺等离子双极电切术(PKRP)患者术中冲洗液吸收的影响。方法:80例BPH患者,择期在腰硬联合麻醉下行PKRP术,随机分为两组,每组40例:0°LP组,常规截石体位,手术床保持水平;-10°LP组,常规截石体位,手术床头低足高倾斜10°。采用含1%乙醇的生理盐水溶液作为术中冲洗液。手术开始即刻,以及随后每10 min应用数字乙醇检测仪对患者呼出气中乙醇浓度进行测试并记录。同时记录两组手术时间,手术期间静脉输注晶体及胶体液量和切除前列腺组织的重量。监测并记录患者的平均动脉血压(MAP)和心率(HR),比较两组患者手术开始前5 min,开始后30 min,手术结束时的MAP和HR。通过动脉血气分析,测定手术开始前、开始后1 h动脉血Na^+、K^+、Cl^-、Ca^2+浓度。结果:两组患者年龄、身高、体重、前列腺体积等无显著差异,术中各时间点MAP和HR亦无显著差异。与术前5 min相比,0°LP组患者手术开始后1 h测得K^+及Ca^2+浓度显著低于术前水平[K^+:(3.49±0.33)mmol/L vs(3.64±0.29)mmol/L,P=0.002;Ca^2+:(1.13±0.04)mmol/L vs(1.16±003)mmol/L,P=0.001],Cl-浓度显著高于术前水平[(108.7±2.3)mmol/L vs(106.9±2.2)mmol/L,P=0.006],而Na^+浓度无明显变化[(139.4±1.6)mmol/L vs(139.7±1.5)mmol/L,P=0.231]。-10°LP组患者Ca^2+浓度低于术前[(1.13±0.04)mmol/L vs(1.14±0.04)mmol/L,P=0.016],Na^+[(140.0±2.0)mmol/L vs(140.3±1.8)mmol/L,P=0.156]、K+[(3.47±0.34)mmol/L vs(3.49±0.36)mmol/L,P=0.506]及Cl^-[(109.1±2.5)mmol/L vs(108.2±2.6)mmol/L,P=0.071]浓度均无明显变化。0°LP组有6例患者(15%),-10°LP组有4例(10%)患者术中冲洗液吸收量>1500 ml,两组比较无统计学差异。结论:头低足高倾斜10°截石位,显著减轻PKRP手术导致的K^+降低,Cl^-升高,但不影响其他电解质变化。     

库存红细胞清洗在新生儿及小婴儿体外循环手术中的应用

Objective Priming blood in cardiopulmonary circuit is necessary for neonates and small infants. However, high concentration of potassium and lactate in pecked red blood cells transfused during cardiopulmonary bypass may have detrimental effects on meonstea and infants undergoing cardiac surgery. This study is to cornice the effects of trasfusing washed end unwashed peeked red blood cells for cardiopulmonary circuit on serum potassium and lactate concentrations preoperatively. Methods 30 neonates and small infants with complex congenitai heart disease undergoing open heart surgery were divided into 2 groups randomly. Unwashed group (n = 15) received unwashed pecked red blood cells and washed group (n=15) received packed red blood cells washed in a cell saver (Medtronic Autolog). Potasium and lactate concertrations were compared before, during and after bypass. Resuils Wash-packed red blood cells reduced donor blood [K+] from (19.3±0.9)mmd/L to (1.1 +0.3) mmol/L, and lactate from 15 mmo/L to (7.8±1.2) mmol/L (P<0.001). The [K+]in the prime solution was significantly higher [(9.0±0.5) mmol/L vs. (2.6±0.1) mmol/L, P<0.001] in umwashed group than that of washed group, so did the lactate [(9.5±2.6) mmol/L vs. (4.7±1.1) mmol/L, P相似文献   

库存红细胞清洗在新生儿及小婴儿体外循环手术中的应用

Objective Priming blood in cardiopulmonary circuit is necessary for neonates and small infants. However, high concentration of potassium and lactate in pecked red blood cells transfused during cardiopulmonary bypass may have detrimental effects on meonstea and infants undergoing cardiac surgery. This study is to cornice the effects of trasfusing washed end unwashed peeked red blood cells for cardiopulmonary circuit on serum potassium and lactate concentrations preoperatively. Methods 30 neonates and small infants with complex congenitai heart disease undergoing open heart surgery were divided into 2 groups randomly. Unwashed group (n = 15) received unwashed pecked red blood cells and washed group (n=15) received packed red blood cells washed in a cell saver (Medtronic Autolog). Potasium and lactate concertrations were compared before, during and after bypass. Resuils Wash-packed red blood cells reduced donor blood [K+] from (19.3±0.9)mmd/L to (1.1 +0.3) mmol/L, and lactate from 15 mmo/L to (7.8±1.2) mmol/L (P<0.001). The [K+]in the prime solution was significantly higher [(9.0±0.5) mmol/L vs. (2.6±0.1) mmol/L, P<0.001] in umwashed group than that of washed group, so did the lactate [(9.5±2.6) mmol/L vs. (4.7±1.1) mmol/L, P相似文献   

Washing of irradiated red blood cells prevents hyperkalaemia during cardiopulmonary bypass in neonates and infants undergoing surgery for complex congenital heart disease.

OBJECTIVE: High concentrations of potassium and lactate in irradiated red cells transfused during cardiopulmonary bypass may have detrimental effects on infants and neonates undergoing cardiac surgery. The effects of receiving washed and unwashed irradiated red cells from the cardiopulmonary circuit on serum potassium and lactate concentrations were compared. METHODS: The study population included neonates and infants undergoing heart surgery for complex congenital heart disease. A control group (n=11) received unwashed irradiated red cells and the study group (n=11) received irradiated red cells washed in a cell saver (Dideco Electa) using 900ml of 0.9% saline prior to pump priming. Potassium and lactate concentrations were compared before, during and after bypass. RESULTS: Washing irradiated red cells reduced donor blood [potassium] from>20 to 0.8+/-0.1mmol/l, and [lactate] from 13.7+/-0.5 to 5.0+/-0.3mmol/l (p<0.001). The resulting prime had significantly lower [potassium] and [lactate] than the unwashed group (potassium 2.6+/-0.1 vs 8.1+/-0.4mmol/l, p<0.001; lactate 2.6+/-0.2 vs 4.6+/-0.3mmol/l, p<0.001). Peak [potassium] in the unwashed group occurred 3 minutes after going on bypass (4.9+/-0.3mmol/l) and during rewarming (4.9+/-0.4mmol/l). These were significantly higher than the washed group (3.1+/-0.1, p<0.001 and 3.0+/-0.1mmol/l, p<0.001). The [potassium] was greater than 6.0mmol/l for 4 out of these 11 unwashed patients compared with none of the washed group. Immediately post-bypass the washed group had significantly lower serum [potassium] (3.2+/-0.1 vs 4.2+/-0.2mmol/l, p=0.002). There was no significant difference in [lactate] between groups during and after cardiopulmonary bypass. CONCLUSIONS: The washing of irradiated red cells reduces potassium and lactate loads and prevents hyperkalaemia during cardiopulmonary bypass. The washing of irradiated red cells should be considered in neonates and infants undergoing cardiac surgery for complex congenital heart disease.     

The effects of venous cannulation technique and cardioplegia type on plasma potassium concentration and arterial blood pressure during cardiopulmonary bypass.

The cannulation method and cardioplegia solution used during cardiopulmonary bypass (CPB) may both influence plasma potassium concentrations ([K+]) and mean arterial blood pressure (MAP). Bi-caval or right atrial cannulation methods are routinely used in conjunction with crystalloid or blood cardioplegia. We investigated the influence of cannulation method and cardioplegia solutions on plasma [K+] and MAP during cardiopulmonary bypass. Sixty consecutive patients undergoing elective coronary artery bypass grafting (CABG) using CPB were studied. They were randomly divided into three groups of 20 patients. Patients in Group A underwent bi-caval venous cannulation and received crystalloid cardioplegia. Group B patients underwent right atrial cannulation and received crystalloid cardioplegia. Group C patients underwent right atrial cannulation and received blood cardioplegia. In each case. cardioplegia was administered antegrade via the aortic root. Plasma [K+], MAP. and hemoglobin concentration (Hb) were measured over an 8-min period following cardioplegia administration (pilot studies indicated pressure changes occuring post cardioplegia administration up to this time). The combination of bi-caval cannulation and crystalloid cardioplegia (Group A) was associated with the least increase in plasma [K+] and no decrease in MAP. The maximum [K+] for this Group was 4.2 mmol/L (4.6% increase). The minimum mean pressure was 57 mmHg (13.6% increase). Both right atrial cannulation groups (B and C) showed a large rise in plasma [K+] and a decrease in MAP. Group B maximum [K+] was 5.2 mmol/L (27.5% increase). Group C was also 5.2 mmol/L (26.0% increase). Group C showed the largest pressure decrease, the minimum mean pressure was 45 mmHg (21.3% decrease). The Group B minimum mean pressure was 45 mmHg (8.7% decrease). Our results show that patients undergoing CPB operations who are deemed to be at increased risk of suffering adverse effects from hypotensive episodes may benefit from bicaval cannulation and caval snaring, in preference to right atrial cannulation. Crystalloid cardioplegia may be preferable to blood cardioplegia in these cases to maintain the MAP.     

Outcome with high blood lactate levels during cardiopulmonary bypass in adult cardiac operation

Background. High blood lactate levels during cardiopulmonary bypass (CPB) are associated with tissue hypoperfusion and may contribute to postoperative complications or death. The objective of this study was to determine an association between blood lactate levels during CPB and perioperative morbidity and mortality.

Methods. We reviewed 1,376 patients who underwent cardiac operation with CPB. Patients with abnormal preoperative blood lactate levels were excluded (n = 101). Blood lactate concentration during CPB, clinical data, and perioperative events were recorded.

Results. Peak blood lactate levels of 4.0 mmol/L or higher during CPB were present in 227 patients (18.0%). Postoperative mortality was higher in this group than in the patients who had peak blood lactate levels of less than 4.0 mmol/L during CPB (11.0% versus 1.4%; p < 0.001, relative risk [RR] = 9.0). Postoperative hemodynamic instability occurred in 29.5% of patients with elevated levels of lactate during CPB compared with 10.9% of patients with lower lactate levels (p < 0.001, RR = 3.4). Overall, major postoperative complications occurred in 43.2% and 21.8% of patients in each group, respectively (p < 0.001, RR = 2.7). Logistic regression analysis revealed that peak blood lactate levels of 4.0 mmol/L or higher during CPB were strongly associated with postoperative mortality (p = 0.0001) and morbidity (p = 0.013).

Conclusions. Blood lactate concentration of 4.0 mmol/L or higher during CPB identifies a subgroup of patients with increased risk of postoperative morbidity and mortality.     

Myocardial preservation during coronary surgery with and without cardiopulmonary bypass

BACKGROUND: There is increased interest in coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB), although the preservation of the myocardium under such circumstances has not been properly investigated. The aim of this randomized study was to compare the changes in myocardial metabolism during CABG with and without CPB. METHODS: Myocardial energy metabolism and tissue injury during CABG was monitored in a series of 22 patients (11 with and 11 without CPB). RESULTS: The maximum myocardial lactate production was significantly higher (p = 0.02) in the group operated with CPB (0.56 mmol/L) than without it (0.17 mmol/L). A similar phenomenon was seen in the transcardiac pH differences (0.085 and 0.034 with and without CPB, p = 0.007). The postoperative peak values of creatine kinase-MB mass (15.1 vs 6.3 microg/L) and troponin I (13.8 vs 5.2 microg/L) were significantly higher (p < 0.001 and p = 0.008) with than without CPB. CONCLUSIONS: CABG on a beating heart is associated with better myocardial energy preservation and less myocardial damage compared with conventional CABG with CPB and intermittent antegrade mild hypothermic blood cardioplegia.     

Changes of lactate levels during cardiopulmonary bypass in patients undergoing cardiac transplantation: possible early marker of morbidity and mortality

Objectives

High levels of lactate are associated with tissue hypoperfusion during cardiac surgery resulting in postoperative morbidity and mortality among patients undergoing cardiopulmonary bypass (CBP). Our goal was to evaluate the change in lactate levels during CBP for their possible predictive value for complications after heart transplant surgery.

Materials and Methods

From January to December 2010 we studied lactate levels in 16 heart transplant patients. Arterial blood samples were collected before, during, and after cardiopulmonary bypass on admission to the intensive care unit (ICU). Lactate levels were measured using the cobas B221 (Roche Diagnostic). The neurological, lung, and kidney complications were associated with mortality within 30 days.

Results

One patient displayed lactate levels > 2 mmol/L before bypass while 4 (25%) showed levels > 4 mmol/L during CPB. Lactate values higher than or equal to 4 mmol/L on ICU admission occurred in nine patients (56%). Postoperative mortality was higher among the group with levels above below 4 mmol/L on ICU admission (18.7% vs 6.2%). Neurological complications were observed in 22% of patients with elevated levels as opposed to none of the patients with levels below 4 mmol/L. Pulmonary complications were noted in 22% of patients with high lactate values versus 0% among the other group.

Conclusion

Hyperlactemia above certain levels occurring during CPB serve as a biomarker to identify early postoperative morbidity and mortality.     

The efficacy of low prime volume completely closed cardiopulmonary bypass in coronary artery revascularization.

PURPOSE: This study was conducted to evaluate and demonstrate the efficacy of low prime volume completely closed cardiopulmonary bypass (LPVP) in arrested coronary artery bypass grafting (CABG). We improved the percutaneous cardiopulmonary support (PCPS) circuit to reduce the deleterious effects of cardiopulmonary bypass (CPB). METHODS: Between April 1999 and May 2003, among 228 isolated CABG procedures, 47 procedures using LPVP (group L) and 86 procedures using standard prime volume open CPB (group S) were compared. The LPVP priming volume was 590 mL; the circuit was completely closed with a soft reservoir. Cardiac arrest was obtained by warm blood cardioplegia. RESULTS: The following average values were obtained: packed red blood cell transfusions, 0.88 +/- 1.4 U (group L) vs. 2.1 +/- 2.5 U (group S); intraoperative lowest hematocrit value, 28.7 +/- 4.6% (group L) vs. 22.4 +/- 3.3% (group S); blood loss over first 24 hours, 439 +/- 242 mL (group L) vs. 599 +/- 409 mL (group S); ventilation time, 5.1 +/- 3.1 hours (group L) vs. 10.4 +/- 14.9 hours (group S). CONCLUSION: Compared to standard prime volume open CPB, LPVP resulted in fewer deleterious operative effects. Less blood loss, fewer blood transfusions, and earlier patient recovery was noted with LPVP. Thus, LPVP is a very efficient form of CPB.     

The effect of hematocrit on cerebral blood flow velocity in neonates and infants undergoing deep hypothermic cardiopulmonary bypass.

Varying degrees of hemodilution are used during deep hypothermic cardiopulmonary bypass. However, the optimal hematocrit (Hct) level to ensure adequate oxygen delivery without impairing microcirculatory flow is not known. In this prospective, randomized study, cerebral blood flow velocity in the middle cerebral artery was measured using transcranial Doppler sonography in 35 neonates and infants undergoing surgery with deep hypothermic cardiopulmonary bypass. Patients were randomized to low Hct (aiming for 20%) or high Hct (aiming for 30%) during cooling on cardiopulmonary bypass (CPB). Systolic (V(s)), mean (Vm), and diastolic (Vd) cerebral blood flow velocity, as well as pulsatility index (PI = [V(s) - Vd]/Vm) and resistance index (RI = [V(s) - Vd]/V(s)) were recorded at six time points: postinduction, at cannulation, after 10 min cooling on CPB, rewarmed to 35 degrees C on CPB, immediately off CPB, and at skin closure. Vm was significantly lower in the high Hct group compared with that in the low Hct group during cooling (P < 0.01). Postinduction, the high Hct group demonstrated significantly lower Vd immediately off CPB (P < 0.01) and significantly lower Vm and V(s) at skin closure (P < 0.001). We conclude that there is an inverse relation between hematocrit and cerebral blood flow velocity during deep hypothermic cardiopulmonary bypass in neonates and infants. Implications: There is an inverse relation between hematocrit and cerebral blood flow velocity during deep hypothermic cardiopulmonary bypass in neonates and infants. Further studies correlating Hct and cerebral blood flow velocity with cerebral metabolic rate and neurologic outcome are necessary to determine the optimal Hct during deep hypothermic cardiopulmonary bypass.     

在深低温停循环中小预充量体外循环的脑保护效果

目的 观察在深低温停循环中小预充量体外循环的脑保护效果.方法 将实验动物分为假手术组(S组)、小预充量组(L组)、大预充量组(H组),建立联合脑微透析和体外循环(CPB)的动物模型.实验中进行微透析取样和生理指标监测,结束后取脑组织作组织学检测,用高效液相色谱法和CMA600分析仪检测微透析样品.结果 实验中,H组所用多巴胺和碳酸氢钠的量高于L组[(2.07±0.63)mg＞(1.12±0.47)mg;(14±3)ml＞(7±3)ml,P＜0.05].检测显示,H组的乳酸/葡萄糖和乳酸/丙酮酸比值在体外循环后高于L组(12.63±0.44＞3.71±1.31;13.14±1.37＞3.82±1.41,P＜0.05);H组的谷氨酸水平在实验后期高于L组(6.02±0.65＞2.21±0.72,P＜0.05);H组脑组织损伤程度明显重于L组.结论 深低温停循环时,与大预充量比较小预充量体外循环有显著的脑保护作用.     

含乌司他丁低温肺保护液在法洛四联症体外循环术中的应用

目的 探讨含乌司他丁(UTI)的低温肺保护液对婴幼儿法洛四联症体外循环肺内炎性反应的保护作用.方法 30例行法洛四联症(TOF)根治术病婴,随机分为肺保护组和对照组,各15例.术前有感染征象(白细胞>12×109/L、体温>38℃,C-反应蛋白>8 mg/L)、有过敏史者除外.肺保护组心脏停跳同时肺动脉灌注低温肺保护液,对照组常规行TOF根治术.围术期监测血浆肿瘤坏死因子(TNF-α)、中性粒细胞CD11b的表达和髓过氧化物酶(MPO),同时监测血气、肺功能及临床指标.结果 血清TNF-α水平肺保护组较对照组低,关胸后0、3 h差异有统计学意义,(11.15±2.47)pg/ml对(14.21±5.55)pg/ml、(12.01±2.69)pg/ml对(15.94±4.86)pg/ml.肺保护组新鲜全血中性粒细胞表面的CD11b平均荧光强度(MFI)水平关胸后3、6 h显著低于对照组,(126.23±36.05)对(156.98±48.34)、(137.27±38.85)对(173.27±67.43).肺保护组MPO水平关胸后3、6、24 h显著低于对照组,(156.52±17.57)U/L对(178.45±35.68)U/L、(178.28±23.63)U/L对(224.66±49.66)U/L、(130.52±57.50)U/L对(96.50±14.49)U/L.肺保护组呼吸机辅助时间明显较对照组短,(17.60±6.39)h对(23.70±8.51)h.肺保护组肺泡-动脉氧阶差(A-aDO2)在关胸后3、6 h显著低于对照组(120.92±33.08)mm Hg(1 mm Hg=0.133 kPa)对(145.52±39.38)mm Hg、(74.76±40.16)mm Hg对(112.50±44.16)mm Hg.肺动态顺应性(Cdyn)在关胸后3、6 h肺保护组显著高于对照组(0.59±0.11)ml·cmH2O-1·kg-1对(0.46±0.17)ml·cmH2O-1·kg-1、(0.67±0.09)ml·cmH2O-1·kg-1对(0.53±0.18)ml·cmH2O-1·kg-1.结论 肺动脉灌注含乌司他丁的低温肺保护液明显减轻体外循环术后肺的炎性反应,具有肺保护作用.