HTK心脏停搏溶液用于心肌保护

德国教授Ｂｒｅｔｓｃｈｎｅｉｄｅｒ基于对自创心脏停搏液的多年研究提出了，高钾应限制在尽可能低的水平，局麻药和葡萄糖基有一定的副作用放度，停搏液的灌注可采用一次高容量冷灌注法，不必格守“按时灌注原则”。ＨＴＫ溶液的最大优点在于心脏停搏和心肌保护的效率高，手术期间不需要其他辅助性心脏保护措施，利于手术操作，从而缩短心肌缺血时间，提高手术成功率。     

心脏停搏液对未成熟心肌的保护作用

使用离体心灌注模型，比较Ｓｔ．ＴｈｏｍａｓＩ号停搏液在１５℃、３０℃时对兔成熟（３～４月）和未成熟（３～４周）心肌的保护效果。１５℃时，两组观察指标无明显差异；３０℃时，未成熟心肌的冠脉流量恢复率较１５℃时明显下降，心肌ＣＫ及ＬＤＨ漏出率、细胞内Ｎａ＋、Ｃａ＋＋含量明显增加（Ｐ＜０．０１）；而成熟心肌与１５℃相比无明显差异。未成熟心肌超微结构１５℃时的病理改变亦较成熟心肌明显。结果显示，Ｓｔ．ＴｈｏｍａｓＩＩ号停搏液对兔未成熟心肌的保护效果不如成熟心肌。     

腺苷心脏停搏液心肌保护效果的研究

腺苷心脏停搏液心肌保护效果的研究王建璞＊王军＊蒋建渝本实验在Ｋ－Ｈ液或ＳｔＴｈｏｍａｓ液的基础上，加入小剂量腺苷，以离体鼠心Ｌａｎｇｅｎｄｏｒｆ灌注模型，研究腺苷心脏停搏液的心肌保护效果。方法实验按四种不同的停搏液成份分为：对照组（Ｃ）：Ｋ－Ｈ液（Ｋ...     

光量子冷血停搏液的心肌保护作用

目的 探讨光量子冷血停搏液的心肌保护效果。方法 建立离体兔心工作模型，将实验动物分为冷晶体停搏液组、冷血停搏液组、光量子冷血停搏液组和温血停搏液组，每组８只。心脏停搏３０分钟，复灌３０分钟。结果 复温复灌１０分钟及３０分钟时，光量子冷血组的冠脉流出量、心肌含水量、心肌内ＡＴＰ和磷酸肌酸（ＣＰ）含量的变化均明显优于冷晶体组和冷血组（Ｐ〈０．０５）。结论 光量子冷血停搏液能够改善心肌本身循环，增加氧的     

HTK心脏停搏溶液用于心肌保护

德国教授Bretschneider基于对自创心脏停搏液的多年研究提出:高钾应限制在尽可能低的水平,局麻药和葡萄糖因有一定的副作用应放弃;停搏液的灌注可采用一次性高容量冷灌注法,不必恪守“按时灌注原则”。HTK溶液的最大优点在于对心脏停搏和心肌保护的效率高,手术期间不需要其他辅助性心脏保护措施,利于手术操作,从而缩短心肌缺血时间,提高手术成功率。     

腺苷停搏液对未成熟心肌的保护作用

目的　探讨腺苷加入停搏液对未成熟心肌的保护作用。方法　 0～ 2d的豚鼠 3 0只 ,随机分为 3组 ,每组 10只。低温组 :局部单纯低温 (15～ 17℃ ) ;Thomas组 :ThomasⅡ号停搏液灌注加低温 ;腺苷组 :腺苷高钾停搏液灌注加低温。平均全心停循环 90min ,再灌注 3 0min。观察诱导心脏停搏时间、冠脉流量恢复率 (CFR)、心肌含水量、超微结构、丙二醛 (MDA )和黄嘌呤氧化酶(XO)的变化。结果　腺苷组诱导心脏停搏时间 (4 .0± 1.1)s较Thomas组 (15 .6± 3 .7)s明显缩短 ;心肌MDA含量 (5 5 .2 6± 3 .3 4)低于Thomas组 (61.49± 3 .70 )和低温组 (64 .92± 3 .2 0 ) ;再灌注末心肌含水量 (77.17± 1.44 ) %少于Thomas组 (79.5 4± 2 .49) %和低温组 (79.48± 1.78) % ;CFR(73 .72± 6.74)高于Thomas组 (67.85± 4.83 )和低温组 (63 .5 5± 4.70 ) ;心肌超微结构改变较轻。 3组间心肌XO差异无显著性 (P >0 .0 5 )。结论　腺苷加入停搏液中对未成熟心肌有保护作用。     

腺苷含血心脏停搏液在心瓣膜置换术中对心肌的保护作用

目的 研究含血心脏停搏液中加入外源性腺苷在心瓣膜置换术中对心肌的保护作用. 方法 将32例行心瓣膜置换术患者随机分为两组,腺苷组在含血心脏停搏液中加入外源性腺苷,对照组单用含血心脏停搏液,分别经主动脉根部或切开主动脉经冠状动脉窦直接灌注.于术前、主动脉开放后6 h、24 h、72 h采集患者桡动脉血,监测心肌肌酸激酶同工酶(CK-MB)、肌钙蛋白I(cTnI);观察心脏停搏情况,术后机械辅助通气时间及术后正性肌力药物的应用情况;透射电子显微镜观察心肌超微结构的改变. 结果 两组患者均无死亡.腺苷组诱导心脏停搏时间较对照组短(P=0.021);腺苷组的CK-MB水平在主动脉开放后6 h、24 h,cTnI水平在主动脉开放后6 h、24 h、72 h均较对照组低(P<0.05);两组机械辅助通气时间和术后多巴胺使用剂量差异无统计学意义(P>0.05);腺苷组心肌超微结构心肌损伤较对照组明显减轻. 结论 外源性腺苷加入心脏停搏液中能显著提高对心肌的保护效果.     

吡那地尔介导超极化心脏停搏液对心肌的保护作用

目的：为了提高心脏停搏液的心肌保护作用，探讨含吡那地尔（pinacidil)超极化心脏停搏液对心肌的保护作用。方法：32只新西兰兔根据体外循环中使用不同的心脏停搏液分为对照组和实验组，对照组用St Thomas Ⅱ号心脏停搏液，实验组用含吡那地尔（50μmol/L）的心脏停搏液。两组又根据主动脉阻断后是否再灌注，分别分为两组（对照组A、对照组B、实验组A、实验组B），每组8只兔。对照组A和实验组A在主动脉阻断60分钟后结束实验；对照组B和实验组B于主动脉阻断60分钟、复滞30分钟结束实验。记录心脏电机械停搏时间，复跳时的心律失常情况，测定实验结束时各组心肌三磷酸腺苷（ATP）、总腺苷酸（TAN）、Ca^2 、丙二醛（MDA）含量，对照组B和实验组B血清心肌酶含量，并观察心肌超微结构变化。结果：4组心脏均迅速发生电机械停搏，对照组B、实验组B复跳时均发生心律失常3例，未发生严重心律失常；实验组A和实验组B的ATP、TAN分别高于对照组A和对照组B（P＜0．01），而Ca^2 和MDA分别显著低于对照组A和对照组B（P＜0．05），实验组B心肌酶的漏出量显著低于对照组B（P＜0．01）。实验组B超微结构损伤轻，优于对照组B。结论：含吡那地尔的心脏停搏液对心肌保护的作用优于高K^ 心脏停搏液。     

不同温度下停搏液对成熟与未成熟心肌的保护作用

目的:观察不同温度下停搏液对成熟与未成熟心肌的保护作用.方法:使用Langendorff离体心脏灌注模型,分别比较St.Thomas No Ⅱ停搏液在15℃、30℃时对成年大白兔(3～4月)和幼兔(3～4周)的心肌保护效果.结果:30℃时,未成熟心肌的冠脉流量恢复率与15℃相比明显下降(P<0.01),心肌肌酸激酶(CK)及乳酸脱氢酶(LDH)漏出率、细胞内N_a~ 、C_a~( )含量明显增加(P<0.01);而成熟心肌30℃与15℃相比各指标无明显差异(P>0.05).且未成熟心肌超微结构15℃时的病理改变较成熟心肌明显.结论:St.Thomas No Ⅱ停搏液对兔未成熟心肌的保护效果不如成熟心肌;低温可增强未成熟心肌的保护效果.     

Re-dosing of del Nido cardioplegia in adult cardiac surgery requiring prolonged aortic cross-clamp

Open in a separate window OBJECTIVESFew data exist on the use of del Nido cardioplegia in adults, specifically during operations requiring prolonged aortic cross-clamp. In this pilot study, we evaluate outcomes of patients undergoing surgery with cross-clamp time >3 h based on re-dosing strategy, using either full dose (FD; 1:4 blood to crystalloid ratio) or dilute (4:1 blood to crystalloid ratio) solution.METHODSConsecutive adult patients (>18 years) undergoing cardiac surgery from 2012 to 2018 with cross-clamp time >3 h were reviewed. Patients were excluded if del Nido cardioplegia was not used. Patients were categorized into FD or dilute groups based on re-dosing solution. Propensity score matching was used to control for baseline differences between groups. The primary endpoint was in-hospital mortality. Other outcomes examined included: postoperative mechanical support, arrhythmia, stroke, dialysis and cardiac function.RESULTSIncluded for analysis were 173 patients (115 male) with median age of 63.8 (interquartile range 53.9–73.1). Major comorbidities included diabetes (45), cerebrovascular disease (34), hypertension (131), atrial fibrillation (52) and previous cardiac surgery (83). There were 108 patients (62%) who received FD re-dosing, while 65 (38%) received dilute. A greater proportion of patients in the dilute group received retrograde delivery, for both induction (32/108 vs 39/65, P < 0.001) and re-dose (50/108 vs 53/65, P < 0.001). After propensity score matching, in-hospital mortality was not different between groups (6/48 vs 1/48, P = 0.131). There were no differences in rates of postoperative mechanical circulatory support, stroke, left ventricular ejection fraction or right ventricle dysfunction.CONCLUSIONSDel Nido cardioplegia has been used in complex cardiac surgery requiring prolonged cross-clamp. Re-dosing can be performed with either FD or dilute del Nido solution with no statistical difference in outcomes.     

Continuous monitoring of myocardial acid–base status during intermittent warm blood cardioplegia

Objective: Intermittent warm blood cardioplegia (IWBC) is a well-established technique for myocardial protection during cardiac operations. According to standardized protocols, IWBC administration is currently performed every 15–20 min regardless of any individual variable and in the absence of any instrumental monitoring. We devised a new system for continuous measurement of the acid–base status of coronary sinus blood for on-line evaluation of myocardial oxygenation during IWBC. Methods: In 19 patients undergoing cardiac surgery for coronary artery bypass graft and/or valve surgery and receiving IWBC (34–37°C) by antegrade induction (3 min) and retrograde or antegrade maintenance (2 min) every 15 min, continuous monitoring of myocardial oxygenation and acid/base status was performed by means of a multiparameter PO₂, PCO₂, pH, and temperature sensor (Paratrend7 ®, Philips Medical System) inserted into the coronary sinus. Results: Mean cross-clamping time was 76±26 min; ischemic time was 13±0.2 min. pH decline was not linear, showing an initial fast decline, a point of flexus, and a progressive slow decline. After every ischemic period, the pH adaptation curve showed a complex pattern reaching step-by-step lower minimum levels (7.28±0.14 during the first ischemic period, to 7.16±0.19 during the third ischemic period – P=0.003). PO₂ decreased rapidly at 90% in 5.0±1.2 min after every reperfusion. During ischemia, PCO₂ increased steadily at 1.6±0.1 mmHg per minute, with progressively incomplete removal after successive reperfusion, and progressive increase of maximal level (42±12 mmHg during the first ischemic period, to 53±23 mmHg during the third ischemic period – P=0.05). Conclusions: Myocardial oxygen, carbon dioxide, and pH show marked changes after repeated IWBC. Myocardial ischemia is not completely reversed by standardized reperfusions, as reflected by steady deterioration of PCO₂ and pH after each reperfusion. Progressive increase of reperfusion durations or direct monitoring of myocardial oxygenation could be advisable in cases of prolonged cross-clamping time.     

冷血心肌麻痹液温度对肌浆网Ca2+摄取和释放的影响

评价冷血心肌麻痹液（ＣＢＣ）温度对肌浆网（ＳＲ）Ｃａ２＋摄取和释放的影响。方法测定ＣＢＣ不同温度停搏１２０分钟和再灌注后心肌匀浆ＳＲ４５Ｃａ２＋摄取及钉红阻滞ＳＲＣａ２＋释放通道后ＳＲ４５Ｃａ２＋摄取的变化。结果停搏期１６℃和２０℃ＳＲ　４５Ｃａ２＋摄取降幅分别为１７．０９％和２１．１６％（Ｐ＜０．０５）;停搏期４、８、１２℃、再灌注后各组ＳＲ　４５Ｃａ２＋摄取与对照组差异均无显著意义（Ｐ＞０．０５）。ＳＲＣａ２＋释放通道阻滞后各组停搏和再灌注后ＳＲ摄４５Ｃａ２＋增幅差异无显著意义（Ｐ＞０．０５）。结论ＣＢＣ温度不同所表现的保护效果差异与ＳＲＣａ２＋摄入受损有关,ＳＲＣａ２＋释放不受影响。     

Reinfusion potassium blood cardioplegia versus cold blood reinfusion alone in elective revascularization

The purpose of this study was to determine if the addition of potassium to reinfusion cold blood cardioplegia (CBC) offers an advantage over cold blood alone. Forty patients matched for age, left ventricular function, extent of coronary disease and number of vessels bypassed were prospectively randomized. Each patient received an initial dose of CB C (10 cc/kg) with potassium. Group I patients (n=23) received subsequent infusions of CBC (5 cc/kg) containing potassium while Group II patients (n=17) received cold blood only. The cross-clamp time, mean infusate volume and temperature were not significantly different in the two groups. Following reperfusion, the cardiac index and the CPK isoenzyme release at 0.5, 1, 8, and 12 h after cross-clamp release were not significantly different between the groups. The postoperative appearance of new Q-waves, inotropic agent requirement, and reversal of the lactate dehydrogenase (LDH) isoenzyme ratio were also not significantly different in the two groups. The study demonstrated that following initial arrest with potassium, cold blood is equally as effective as potassium blood cardioplegia in protecting the ischemic myocardium.     

Combined cardioplegia delivery offers no advantage over antegradecardioplegia administration in coronary surgical patients with a preserved left ventricular function

The effects of antegrade and of combined antegrade and retrograde cardioplegia were compared in 101 patients undergoing elective coronary artery surgery. The patients were randomly allocated to two groups. antegrade cardioplegia was administered in 53 patients and combined cardioplegia in 43 patients. The patients of the two groups were similar in age, sex and left ventricular ejection fraction. Aortic clamping time and the number of coronary bypasses were equal in the groups. The ventricular septal temperature was measured continuously during cardioplegia administration, after each distal anastomosis accomplished, and continuously after aortic declamping. Serum CK-MB activities were serially measured for up to 3 days postoperatively. Electrocardiograms (ECG) were taken preoperatively, as well as on the first, second and eighth postoperative days. The left ventricular function was evaluated with a volume load test preoperatively and on the first postoperative morning. The two groups were similar with respect to myocardial cooling, response to volume loading, the number of patients with perioperative myocardial infarctions, cardiac arrhythmias or atrioventricular conduction blocks and clinical outcome. However, the CK-MB activities were lower in the antegrade group suggesting better myocardial protection in an unselected group of patients undergoing coronary artery bypass grafting.     

冷血停搏液对法洛四联症婴幼儿心肌代谢的影响

目的：通过临床应用，评价冷血停搏液对未成熟心肌代谢的影响。方法：50例行择期法洛四联症根治术病儿随机分为2组，对照组用10℃改良St.Thomas 1停搏液（CCP），试验组用冷血停搏液（BCP），阻断升主动脉前，开放升主动脉1，3，10min分别由冠状静脉窦和动脉同时取血测定血气，电解质，乳酸，丙二醛（MDA）等含量。结果：再灌注后BCP组心肌氧提取率，乳酸摄取率恢复较快（P＜0．05），再灌注各时点两组均出现钾离子释放和MDA升高；再灌注后BCP组钙离子摄取较低（P＜0．05），结论：冷血停搏液对再灌注后的离子平衡，氧化谢，糖代谢恢复优于冷晶体停搏液。     

Comparison of single- and multi-dose crystalloid cardioplegia to protect the immature myocardium

The primary objective of this study was to compare the protective effects of single-dose and multi-dose St. Thomas' Hospital cardioplegic solution number 1 in the ischemic and reperfused neonatal rabbit heart. In addition, the effect of including bicarbonate (a component of St. Thomas' Hospital cardioplegic solution number 2) was also studied. Hearts (n=8 per group) were excised from rabbits (7–10 days old) and aerobically perfused in the working mode with crystalloid media for 20 min (37°C). After assessing cardiac function, the hearts were arrested by an infusion of cold cardioplegic solution (2 min at 15°C with or without the addition of bicarbonate (10 mmol). The hearts were then subjected to 6 h of hypothermic ischemia (15°C and, during this period, some hearts received multiple infusions (2 min/h at 15°C) of cardioplegic solution. All hearts were reperfused for 35 min (15 min Langendorff plus 20 min working), cardiac function was then re-assessed and expressed as a percent of the preischemic value. The coronary effluent, collected during the first 15 min of reperfusion, was assayed for creatine kinase activity. At the end of the reperfusion period, the hearts were freeze clamped and taken for metabolic analysis. With multi-dose cardioplegia (without bicarbonate) the postischemic recovery of cardiac output was 67.0±6.5% and with single-dose the value was 39.3±10.0% (NS). The same pattern of postischemic recovery (that varied between 30% and 60%) for aortic flow, stroke volume and stroke work was observed with both multi-dose and single-dose infusion. The inclusion of bicarbonate in the cardioplegic solution did not significantly alter the recovery of cardiac output with single-dose (51.7±8.9% vs 39.3±10.0%) or multi-dose infusion (60.6±7.6% vs 67.0±6.5%). Creatine kinase leakage was similar in all groups, as was the myocardial high energy phosphate content. In conclusion, in the neonatal rabbit heart, multi-dose St. Thomas' Hospital cardioplegia affords similar protection to single-dose administration and this was not modified by the addition of bicarbonate.