温血停搏液持续与间断灌注在冠状动脉搭桥术中的比较研究

目的 比较温血持续与间断灌注心脏停搏液在冠状动脉搭桥术中心肌保护效应。方法将30例冠状动脉搭桥手术随机分为温血持续灌注组（n=15）;温血间断灌注组（n=15）,灌注心脏停搏液,在常温体外循环下分别于切皮前、转流60min、停机6、12h采集动脉血,以ELISA法测定血浆心肌肌钙蛋白T（cTnT）浓度。分别取主动脉阻断前、开放后心肌组织,观察三磷酸腺苷（ATP）含量及心肌超微结构。结果 温血间断组 cTnT在停机6h时点比温血持续组有显著性差异（P<0.05）。两组术中60min、停机6hcTnT升高,停机24h逐渐恢复术前水平。两组ATP含量比主动脉阻断前有显著性差异（P<0.05）。温血间断组线粒体计分主动脉阻断开放后比主动脉阻断开放前有显著性差异（P<0.05）,温血持续组略升高（P<0.05）。结论 常温体外循环中温血持续灌注停搏液优于温血间断灌注停搏液的心肌保护作用。     

Warm blood cardioplegia as an adjunct to myocardial preservation during coronary artery bypass grafting

A review of the first 52 consecutive coronary artery bypass surgery patients to receive oxygenated blood cardioplegia, with warm reperfusion cardioplegia ('hot shot'), was undertaken to evaluate its effectiveness in myocardial protection. The chosen parameters of ischaemia were: (i) the occurrence of ventricular fibrillation (VF) on release of the aortic cross-clamp (ACC); (ii) the occurrence of bradycardia due to cardiac conduction defects; (iii) the use of inotropes with or without the use of the intra-aortic balloon pump (IABP); (iv) evidence of myocardial infarction (MI) on the postoperative electrocardiograph (ECG); and (v) peri-operative cardiogenic mortality. Warm induction cardioplegia was cooled after cardiac standstill. Repeat cold cardioplegia was given as required at intervals and warm reperfusion cardioplegia was given prior to release of the ACC. Of the 52 patients studied none developed VF after release of the ACC; one patient with pre-operative complete heart block required temporary cardiac pacing; no patient required inotropes or IABP and there was no postoperative MI or mortality. The warm blood cardioplegia technique has not resulted in any detectable evidence of inadequate myocardial protection. A beneficial effect has been demonstrated by the absence of VF, cardiac conduction defects, myocardial failure, MI and mortality.     

体外循环和非体外循环冠状动脉旁路术围手术期心肌损伤程度的对比研究

目的　对比研究常规体外循环下冠状动脉旁路术 (CCABG)和非体外循环心脏跳动下冠状动脉旁路术 (OPCAB)围手术期心肌肌钙蛋白I(cTnI)动态变化规律 ,以明确心肌损伤的程度。方法　 5 9例不稳定心绞痛患者 ,射血分数 (EF) 0 35～ 0 5 6 ,其中 34例行OPCAB ,患者平均年龄 (5 9 1± 1 7)岁 ,平均搭桥数 1 0～ 5 0支 ,平均 (2 90± 0 8)支 ;2 5例行CCABG ,患者平均年龄 (5 6 5± 1 8)岁。搭桥数 2 0～ 5 0支 ,平均 (3 2± 0 7)支。分别在术前 ,术后第 8、2 4、48、72、96、12 0h时 ,采集患者静脉血标本 ,离心后取血浆测定cTnI值。cTnI的测定采用自动双抗体夹心酶联免疫荧光测定法 ,仪器检测灵敏度cTnI 0 35 μg/L。　 结果　术前 2组患者cTnI差异无显著性意义 (P >0 0 5 )。OPCAB手术组cTnI值在术后观察期内均低于CCABG组 ,差异有显著性意义 (t=1 9432 ,P =0 0 0 7)。全组患者无死亡 ,均痊愈出院。　结论　cTnI是诊断心肌损伤的良好指标。OPCAB手术心肌损伤程度显著低于CCABG手术。     

The insulin cardioplegia trial: myocardial protection for urgent coronary artery bypass grafting

BACKGROUND: Small, nonrandomized clinical trials have demonstrated a beneficial effect of solutions containing insulin and glucose on the recovery of myocardial metabolism and ventricular function after cardioplegic arrest and reperfusion. However, no large, blinded, randomized study has yet determined the effects of insulin-enhanced cardioplegia on clinical outcomes after coronary artery bypass grafting. METHODS: The Insulin Cardioplegia Trial was designed to evaluate the clinical impact of insulin-enhanced cardioplegia on patients at high risk undergoing isolated coronary artery bypass grafting for unstable angina. A total of 1127 patients were randomly assigned at operation to receive cardioplegic solution supplemented with 10 IU/L insulin (n = 557) or placebo (n = 570). All personnel with direct patient contact were blinded to randomization group. RESULTS: Overall operative mortality was 2.2%, with no significant differences between groups. The prevalences of postoperative low output syndrome (insulin 10.4%, placebo 9.7%, P =.7) and enzymatic myocardial infarction (insulin 21.0%, placebo 18.8%, P =.3) were not different between groups. The primary composite outcome of low output syndrome and/or enzymatic myocardial infarction revealed no difference between groups (insulin 30.0%, placebo 26.3%, P =.2). CONCLUSIONS: Despite encouraging results from smaller, nonrandomized studies, the Insulin Cardioplegia Trial failed to demonstrate a clinical benefit of insulin-enhanced cardioplegic solution for patients undergoing high-risk isolated coronary artery bypass grafting.     

Effect of cold blood cardioplegia enriched with potassium-magnesium aspartate during coronary artery bypass grafting

AIM: The aim of this investigation is to evaluate the effect of enriched with potassium-magnesium aspartate cold-blood cardioplegia on early reperfusion injury and postoperative arrhythmias in patients with ischemic heart disease undergoing coronary artery bypass grafting (CABG), using measurements of cardiac troponin I (CTnI), hemodynamic indexes and clinical parameters. METHODS: Forty patients with three-vessel coronary artery disease (CAD) and stable angina, receiving first-time elective CABG, were randomly divided into 2 groups: patients in control group (C group n=20) received routine institutional cold blood cardioplegia (4 degrees C) concentration of Mg2+4 mmol/L, Ca2+1.2 mmol/L and K+ 24mmol/L during myocardial arrest. Patients in P group (n=20) received modified cold blood cardioplegia enriched with potassium-magnesium aspartate and maintained concentration of Mg2+10 mmol/L, Ca2+1.2 mmol/L and K+20mmol/L in the final blood cardioplegia solution. Clinical outcomes were observed during operation and postoperatively. Serial venous blood samples for CTnI were obtained before induction, after cardiopulmonary bypass (CPB), and postoperative 6, 24, and 72 hours. Hemodynamic indexes were obtained before and after bypass by the radial catheter and Swan-Ganz catheter. RESULTS: In both groups, there were no differences regarding preoperative parameters. There were no cardiac related deaths in either group. The time required to achieve cardioplegic arrest after cardioplegia administration was significantly shorter in P group (47.5+/-16.3 s) than in C group (62.5+/-17.6 s) (P<0.01). The number of patients showing a return to spontaneous rhythm after clamp off was significantly greater in P group (n=20, 100%) than in C group (n=14, 70%) (P<0.01). Eight patients in C group had atrial fibrillation (AF) compared with two patients in P group (P<0.05) in the early of postoperative period. The level of CTnI increased 6 hours and 12 hours postoperatively, and there was a significant difference between groups (P<0.05). P group also shortened the time of postoperative mechanical ventilation (P<0.05) after surgery. CONCLUSIONS: Cold blood cardioplegia enriched with potassium-magnesium aspartate is beneficial on reducing reperfusion injury.     

Serial assessment of left ventricular performance following coronary artery bypass grafting. Early postoperative results with myocardial protection afforded by multidose hypothermic potassium crystalloid cardioplegia

Forty patients who recently underwent coronary artery bypass graft (CABG) operations had serial hemodynamic and scintigraphic studies. Multidose hypothermic potassium crystalloid cardioplegia was used for myocardial protection and newer techniques in anesthetic management and perioperative patient care were also employed. The method of equilibrium cardiac gated blood pool (GBP) scintigraphy was used to obtain perioperative changes in global ejection fraction (EF) and regional wall motion (RWM). Ninety percent of patients displayed a decrease in EF 2 hours postoperatively when compared to their preoperative values. This change was also associated with a fall in cardiac index (CI) and left ventricular stroke work index (LVSWI). Twenty-four hours postoperatively, EF and CI recovered to preoperative levels, but LVSWI remained depressed. Seven days postoperatively, global EF had improved to a value greater than the preoperative one (50% +/- 3% versus 57% +/- 4%, p < 0.05). Perioperative changes in RWM followed the same pattern as EF, but recovery in this index of regional contractility was faster than EF, since maximal improvement was observed 24 hours postoperatively. Thus transient left ventricular dysfunction is common immediately after CABG, but recent advances in myocardial protection and perioperative management are associated with short-term increases in regional and global left ventricular function documented by noninvasive GBP imaging.     

体外循环与非体外循环冠状动脉旁路移植术补钾影响因素的比较

目的 探讨常规冠状动脉旁路移植术(CCABG)与非体外循环冠状动脉旁路移植术(OPCABG)围术期钾离子变化特点与补钾影响因素.方法 50例接受CABG患者,分为CCABG组和OPCABG组,每组25例.术中根据血气结果补钾,维持血清钾离子浓度在4.0～5.0mmol/L.记录并比较两组术中及术后液体出入量、补钾量、单位时间补钾量(补钾量/手术时间)、尿钾浓度、尿排钾量(总尿量×平均尿钾浓度)以及心肺转流(CPB)指标,分析两组术中补钾量的独立影响因素.结果 CCABG组术中补钾量及单位时间补钾量均高于OPCABG组,但其CPB前后单位时间补钾量低于OPCABG组(P＜0.05);CCABG组桥血管数、手术时间、术中尿量、尿排钾量及术后24 h补钾量均大于OPCABG组,术中平均尿钾浓度和最低体温低于OPCABG组(P＜0.05).多元线性回归分析显示尿量和入室血钾浓度是OPCABG组术中补钾量的独立影响因素;年龄和CPB转机时间是CCABG组术中补钾量的独立影响因素(P＜0.05).结论 CABG围术期需积极补钾.OPCABG中应根据基础血清钾水平结合尿量尽早开始补钾;CCABG中应根据CPB时间合理补钾.     

缺血预处理与温-冷-温技术在冠状动脉旁路移植术中对心肌的保护作用

目的通过监测血浆肌酸激酶同工酶(CK-MB)、心肌肌钙蛋白I(cTnI) 的水平,评价三种不同的心肌保护方法在冠状动脉旁路移植术(CABG)中的应用. 方法将36例均为稳定型心绞痛、3支血管病变、首次施行CABG患者随机分成3组缺血预处理组、温血组、对照组, 观察临床结果和术后应用血管活性药情况,并于转流前、术毕、术后6～12 、24 、72小时和第6天分别抽静脉血测定 CK-MB、cTnI. 结果缺血预处理组和温血组的自动复跳率均为100%,明显高于对照组(58%); cTnI 和CK-MB的水平从术后6～12小时开始升高(P<0.05),在24小时达到峰值,在术后第6天恢复.与对照组比较缺血预处理组和温血组在术后6～12、24、72小时时cTnI 和CK-MB的水平明显低(P<0.01). 结论多次短时间的缺血预处理和"温-冷-温"技术在低危CABG患者中较常规方法更有利于对缺血心肌的保护.     

Biochemical indicators of myocardial ischaemia during coronary artery bypass grafting

Metabolic indicators of myocardial ischaemia were measured in coronary sinus blood in six patients undergoing coronary artery bypass grafting (CABG). Five arterial and coronary sinus blood samples were taken in each case--one before cardiopulmonary bypass (CPB), and three during and one after CPB. Moderate hypothermia with topical cardiac cooling and cold cardioplegia were used. Myocardial infarction occurred perioperatively in two patients. Myocardial lactate production was not found before CPB in any patient, but it was common during CPB. Adenosine, inosine and hypoxanthine were released into the coronary sinus blood, but their release did not correlate significantly with lactate production. Myocardial noradrenaline production showed positive correlation with lactate levels (p less than 0.05). Release of adrenaline from the myocardium during CABG was also demonstrated. Myocardial catecholamine production was especially seen in the patients with myocardial infarction. Myocardial catecholamine release seemed to be the most sensitive of the studied biochemical indicators of myocardial ischaemia during CABG.     

Normothermic versus hypothermic perfusion during primary coronary artery bypass grafting

Normothermic versus hypothermic cardiopulmonary bypass was evaluated in 1442 consecutive patients undergoing primary coronary artery bypass grafting (CABG). Group 1 (n = 545) were operated on in moderate systemic hypothermia (rectal temperature 28 °C) and group 2 (n = 897) in normothermia (rectal temperature 37 °C). Both groups had cold cardioplegic arrest (10 °C) and local cooling of the heart with slush. Anaesthesia and operative techniques were identical in both groups. The mean age was 60 years; group 2 contained significantly more patients aged >65 years (P<0.05) and had more frequent emergency operations (P<0.001) than group 1. Other preoperative patient characteristics were similar between groups. Aortic cross-clamping time was similar in both groups but cardiopulmonary bypass time was significantly longer in group 1 than in group 2 (97.9(28.8) versus 76.6(26.0) min, P<0.001), Perioperative mortality rate was 3.3% in group 1 and 2.6% in group 2. The incidence of myocardial infarction was significantly higher in group 1 than in group 2 (2.0% versus 0.7%) Perioperative low cardiac output needing inotropic support was similar in both groups, but group 1 patients required more intra-aortic balloon insertions (4.6% versus 2.2%, P<0.05). Lower incidence of postoperative ventricular arrhythmias, shorter intubation time and less transient renal failures were significant in group 2 compared with those in group 1 (P<0.001), while re-exploration of bleeding, wound infections, pulmonary, neurological and gastrointestinal complications did not differ. Blood transfusion was less in group 2 (1.2(1.1) units, P<0.001). On day 1 after surgery, serum creatinine, lactate dehydrogenase and creatine phosphokinase values were increased in both groups but were significantly lower in group 2 (P<0.001). Normothermic cardiopulmonary bypass combined with cold cardioplegic arrest is safe and provides sufficient cardiac and total body protection during primary CABG. Several of the adverse effects of hypothermia can be avoided, such as prolonged cardiopulmonary bypass time and ventilatory support, disturbed haemostasis and transient renal failure.     

Influence of diabetes on mortality and morbidity: off-pump coronary artery bypass grafting versus coronary artery bypass grafting with cardiopulmonary bypass

BACKGROUND: Myocardial revascularization in diabetic patients is challenging with no established optimum treatment strategy. We reviewed our coronary artery bypass grafting experience to determine the impact of eliminating cardiopulmonary bypass on outcomes in diabetic patients relative to nondiabetic patients. METHODS: From January 1995 through December 1999, 9,965 patients, of whom 2,891 (29%) had diabetes, underwent isolated coronary artery bypass grafting. Diabetic and nondiabetic patients were further divided into groups on the basis of cardiopulmonary bypass use. Twelve percent (346 of 2,891) of diabetic patients and 12% (829 of 7,074) of nondiabetic patients underwent coronary artery bypass grafting without cardiopulmonary bypass; the remainder had coronary artery bypass grafting with cardiopulmonary bypass. Nineteen preoperative variables were compared among treatment groups by univariate analysis. RESULTS: Patients undergoing coronary artery bypass grafting without cardiopulmonary bypass compared with those having coronary artery bypass grafting with cardiopulmonary bypass had higher mean predicted mortalities (diabetic, 3.96% versus 3.72%, p = 0.83; nondiabetic, 3.03% versus 2.86%, p = 0.79). In nondiabetic patients, coronary artery bypass grafting without cardiopulmonary bypass provides an actual and risk-adjusted survival advantage over coronary artery bypass grafting with cardiopulmonary bypass (1.81% versus 3.44%, p = 0.0127; risk-adjusted mortality, 1.79% versus 3.61%, p = 0.007). This survival benefit of coronary artery bypass grafting without cardiopulmonary bypass was not seen in diabetic patients (2.89% versus 3.69%, p = 0.452; risk-adjusted mortality, 2.19% versus 2.98%, p = 0.42). Diabetic patients undergoing coronary artery bypass grafting without cardiopulmonary bypass had fewer complications, including decreased blood product use (34.39% versus 58.4%, p = 0.001), and reduced incidence of prolonged ventilation (6.94% versus 12.10%, p = 0.005), atrial fibrillation (15.90% versus 23.26%, p = 0.002), and renal failure requiring dialysis (0.87% versus 2.75%, p = 0.036). CONCLUSIONS: The survival advantage in nondiabetic patients treated with coronary artery bypass grafting without cardiopulmonary bypass is not apparent in diabetic patients. Coronary artery bypass grafting without cardiopulmonary bypass in diabetic patients is nevertheless associated with a significant reduction in morbidity.     

Optimal myocardial protection strategy for coronary artery bypass grafting without cardioplegia: prospective randomised trial

Although hypothermia and ischaemic preconditioning (IP) are independently recognised mechanisms of cardioprotection, interactions between myocardial temperature and preconditioning have not been investigated. Therefore, this study explored the possibility of inducing IP during hypothermia and quantifying its effects at two temperature regimens commonly used in clinical practice. One hundred and four patients undergoing coronary artery bypass grafting (CABG) with intermittent cross-clamping and ventricular fibrillation were randomised to four groups: N=normothermia (36.5+/-0.5 degrees C); NP=normothermia+preconditioning, H=hypothermia (31.5+/-0.5 degrees C), HP=hypothermia+preconditioning. The primary outcome measure was release of cardiac Troponin I (cTnI), measured at 6 time points from pre- to 72 h after the end of CPB. There were no hospital deaths and no significant differences in pre- and intra-operative variables (P>or=0.05). There were significant differences in cTnI release between all groups, as follows: N: 117+/-12 microg/l (P相似文献   

Retrograde continuous warm blood cardioplegia reduces oxidative stress during coronary artery bypass grafting.

Myocardial oxidative stress during retrograde continuous blood cardioplegia (RCBC) was evaluated in 22 patients undergoing elective aortocoronary bypass surgery. The patients were divided into two groups: Group C (n=11) received cold RCBC, and Group W (n=11) received warm RCBC. Myocardial oxidative stress was assessed by measuring the release of oxidized glutathione (GSSG), malondialdehyde (MDA), and myeloperoxidase (MPO) in the coronary sinus plasma before aortic clamping, at 1, 5, and 10 minutes after unclamping. Both the hemodynamic recovery and the creatine kinase MB (CKMB) activity were measured perioperatively until 24 hours after unclamping. In Group C, a significant coronary sinus release of GSSG was found in the early reperfusion period in comparison to Group W. No significant difference in the release of MDA nor MPO was noted in the two groups. The recoveries in the left and right ventricular functions, and the peak CK-MB activity were similar in both groups. In conclusion, warm blood cardioplegia is thus considered to protect the myocardium from ischemia-reperfusion injury better than cold blood cardioplegia under retrograde continuous perfusion.     

Propofol attenuates myocardial lipid peroxidation during coronary artery bypass grafting surgery

Background. Propofol can scavenge free radicals because it hasa chemical structure similar to antioxidants. Methods. We examined if free radical scavenging occurs withpropofol during CABG operations. We studied 24 patients undergoingCABG surgery for triple vessel disease, randomized into twogroups. After induction of anaesthesia with fentanyl 10 µgkg^–1 and midazolam 0.1 mg kg^–1, patients in thefentanyl group (n=14) received fentanyl infusion 10–30µg kg^–1 h^–1 and patients in the propofol group(n=10) received propofol infusion 3–6 mg kg^–1 h^–1for maintenance of anaesthesia. Atrial tissue biopsies weretaken during cannulation for bypass, 45 min after cross-clampinsertion, 5 min after unclamping, and in the decannulationperiod. Lipid peroxidation was assessed by measurement of thiobarbituricacid reactive substances (TBARS) in the atrial tissue samples. Results. Lipid peroxidation in the propofol group was less thanin the fentanyl group (P<0.05) in all sampling periods. Lipidperoxidation in the fentanyl group increased significantly duringcardiopulmonary bypass (CPB) (P<0.05), but no increase wasfound in the propofol group (P>0.05). Conclusion. In clinical doses, propofol strongly attenuateslipid peroxidation during CABG surgery. Br J Anaesth 2002; 89: 242–6     

Cold blood cardioplegia versus cold crystalloid cardioplegia: a prospective randomized study of 1440 patients undergoing coronary artery bypass grafting

OBJECTIVES: A large number of experimental studies have indicated that blood cardioplegia might be superior to crystalloid cardioplegia for myocardial protection during ischemic arrest. However, no prospectively randomized studies of large patient series have been undertaken to prove potential differences in clinical course. METHODS: Over a 52-month period, all patients undergoing on-pump coronary artery bypass operated on by 2 surgeons were prospectively randomized to receive either cold crystalloid cardioplegia (group C) or cold blood cardioplegia (group B) during aortic crossclamping. RESULTS: Altogether, 1440 patients aged 37 to 89 years (median, 66 years) entered the study (group C, n = 719; group B, n = 721). The groups were comparable in all major demographic, preoperative, and operative variables. The clinical course turned out to be nearly identical for both groups. No statistically significant differences were seen concerning spontaneous sinus rhythm after aortic declamping, use of inotropic drugs or intra-aortic balloon pumping, postoperative ventilatory support, bleeding and rate of allogeneic blood transfusions, perioperative myocardial infarction, episodes of atrial fibrillation, stroke or minor neurologic dysfunction, renal function, infections, physical rehabilitation, or mortality. Also, in subgroups of patients at higher operative risk (female sex, age >70 years, unstable angina, diabetes, emergency operation, ejection fraction <0.50, crossclamping time >50 minutes, and EuroSCORE >4), no statistically significant differences could be demonstrated between the groups. CONCLUSIONS: There were no significant differences whether myocardial protection was performed with cold blood cardioplegia or cold crystalloid cardioplegia during aortic crossclamping in patients undergoing coronary artery bypass grafting. The extra costs related to blood cardioplegia might be saved.