非体外循环下行双向格林手术(附58例报道)

目的　总结非体外循环下行双向格林手术的体会。方法　 2 0 0 0年 5月至 2 0 0 1年 9月 ,在非体外循环下行双向格林手术 5 8例。年龄 (3 5 4± 1 5 9)岁 ,体重 (13 6± 4 0 )kg。上腔静脉与右心耳插管临时转流 ,自上腔静脉入右房处横断上腔静脉 ,缝闭近心端 ,应用可吸收线端侧吻合远心端与右肺动脉 ,前壁用自体心包片加宽。结果　全组无手术死亡 ,术后并发乳糜胸 4例 ,一过性昏迷 1例。腔静脉阻断 (48± 15 )min ,术前氧饱和度 0 75± 0 0 9,肺动脉压 (12 8± 2 3)mmHg(1mmHg=0 133kPa) ;术毕氧饱和度 0 93± 0 0 5 ,肺动脉压 (16 5± 2 9)mmHg,胸腔及心包引流液 (145± 10 3)ml,呼吸机辅助 (13± 7)h ,住院 (10± 5 )d。结论　非体外循环下行双向格林手术是一种安全、可靠的术式。对于难以解剖根治或一期生理矫治的肺血少的复杂先天性心脏病 ,该术式是一种良好的手术方法。     

Improved outcomes during cardiac surgery: a multifactorial enhancement of cardiopulmonary bypass techniques

Patients presenting for cardiac surgery with cardiopulmonary bypass (CPB) are more likely to have pre-existing comorbidities, which has resulted in a steady increase in the risk associated with CPB. The resulting challenge has mandated the optimization of perfusion care. The purpose of this study was to retrospectively evaluate the impact of a number of simultaneous, evidence based perfusion care changes on patient outcome. After Institutional Review Board approval, two groups of patients were compared. The control group (n = 317) included all patients undergoing CPB in a 12-month period preceding a multifaceted change in perfusion techniques. The treatment group (n = 259) included all patients undergoing CPB in the 12-month period after the changes, which included the incorporation of updated continuous blood gas monitoring, biocompatible circuitry, updated centrifugal blood propulsion, continuous autotransfusion technology, new generation myocardial protection instrumentation, plasmapheresis, topical platelet gel application, excluding hetastarch while increasing the use of albumin, viscoelastographic coagulation monitoring, and implementing a quantitative quality improvement program. After univariate analysis, propensity scoring and multiple conditional logistical regression were used to control for demographic, preoperative, operative, and postoperative parameters. Results of the primary endpoints revealed a lower mortality rate in the treatment group (4% vs. 9% [95% confidence interval 1.33, 7.72], p = 0.009), lower transfusion rate (51% vs. 59% [1.00, 2.11], p = 0.048), and lower complication rate (55% vs. 65% [1.06,2.19], p = 0.025) despite having similar predicted mortality (11 [2,22] vs. 11[3,22], p = NS) and other preoperative and operative parameters. The lower mortality rate was concurrent with a trend towards a lower incidence of complications, consistent with the differences in primary outcomes. In conclusion, the patients treated after the implementation of a multifactorial improvement plan using evidence based changes in CPB care had decreased complication and mortality rates.     

The effect of temperature and aprotinin during cardiopulmonary bypass on three different methods of activated clotting time measurement

The activated clotting time (ACT) is used frequently for monitoring blood anticoagulant response with heparin before, during, and after cardiopulmonary bypass (CPB). Many cardiac procedures involving CPB require reduction of the patient's blood temperature and use of the serine protease inhibitor, aprotinin. Three different methods of ACT measurement were compared to show the effects of different CPB temperatures and the presence of aprotinin. A total of 42 patients were included in the study: 14 received CPB at 28 degrees C, 14 received CPB at 32 degrees C, and 14 normothermic (37 degrees C) CPB. Within each temperature group, seven received aprotinin. The ACT in each group of patients was measured by a celite activator (C-ACT), a kaolin activator (K-ACT), and a celite, kaolin and glass activator (MAX-ACT). All three methods of ACT measurement showed significant increases (p < .05) in clotting times at hypothermic CPB compared with normothermic groups. During heparinization the C-ACT was significantly increased (p < .05) in the presence of aprotinin. Comparability between the 3 ACT measurement methods showed a very high correlation between C-ACT and K-ACT clotting times (R2 = .8962), and slightly lower correlation between MAX-ACT and C-ACT (R2 = .7780), and MAX-ACT and K-ACT (R2 = .7827). All ACT measurements are affected by changes in blood temperature. The C-ACT measurement is prolonged with aprotinin, whereas the MAX-ACT and K-ACT method of measurement in the presence of aprotinin are not significantly altered. It appears that the MAX-ACT produces lower values and may necessitate additional heparin therapy for ACT target values considered safe during CPB. Further study is required from these additional findings.     

Rupture of extra-corporeal circuit tubing during cardiopulmonary bypass

Roller pumps are widely used for cardiopulmonary bypass in developing nations by virtue of proven safety during several years of institutional use and cost effectiveness. However, careful adjustment of roller occlusion is needed because they are known to cause spallation, tubing wear, and the occasional incident of rupture of tubing in the extracorporeal circuit. Rupture of polyvinylchloride tubing in the pump raceway during repair of a ventricular septal defect in a 4-year-old child is discussed. The event was managed by exclusion and replacement of the defective tubing during a short period of arrest. Use of an inappropriate boot pump and failure to detect its inclusion in the bypass circuit was a significant departure from protocol. However, because occlusion settings and duration of perfusion were within acceptable limits, a manufacturing flaw could also have contributed to tubing failure, and the event may or may not have been averted by the use of larger tubing. In conclusion, this incident reiterates the need for adherence to established protocol during assembly of the pump and draws attention to the fact that tubing integrity is not a guarantee and vigilance is warranted to handle its failure.     

心肺转流心脏手术用乌司他丁对肾功能的影响

目的研究乌司他丁对心肺转流（CPB）心脏手术患者。肾功能的影响。方法30例拟行心脏瓣膜置换手术患者,分为两组,每组各15例。对照组未用药（C组）,实验组乌司他丁（U组）。实验组（U组）给予乌司他丁2万U／kg,体外循环前静脉滴入1／3量,体外循环机内预充1／3量,开放升主动脉后给予1／3量。术后第1、2、3天分别静脉输注乌司他丁0．5万U/kg,对照组（C组）给予等量生理盐水。分别于术前（T0）、术后1d（T1）、3d（T3）、5d（T5）、7d（T7）检测血清尿素氮（BUN）、血清肌酐（Cr）、血清β2-微球蛋白（β2-MG）、尿视黄醇结合蛋白（RBP）、尿β2-微球蛋白（β2-MG）的含量。结果①BUN、Cr：C组术后T1和T3显著高于术前及U组同一时点值（P〈0．05）;②血清β2-MG：C组术后仅T1、T3明显高于术前及U组同一时点值（P〈0．05）;③尿RBP：C组术后各时点值及U组T1、T3值明显高于术前值（P〈0．01）,两组术后各时点比较,U组明显低于C组（P〈0．01）;④尿β2-MG：C组术后各时点值显著高于术前值（P〈0．01）,U组T1、T3明显高于术前值（P〈0．05）,两组间术后各同一时点值比较有统计学差异（P〈0．01）。结论乌司他丁对心肺转流（CPB）心脏手术后患者。肾功能有一定保护作用。     

Isoflurane and hypothermic cardiopulmonary bypass: vasodilation without metabolic effects

During cardiopulmonary bypass, isoflurane may have beneficial effects on systemic oxygen uptake and vascular resistance. For this reason, the effects of isoflurane during low-flow (1.6 L/min/m2), hypothermic (27 degrees to 29 degrees C) cardiopulmonary bypass on systemic hemodynamics and oxygen uptake were studied in 20 patients in a cross-over experiment. Mean arterial and central venous pressures were measured during two consecutive periods of 10 minutes' duration. Blood samples were aspirated at the end of each period from the arterial and venous lines and analyzed for oxygen content. The concentration of isoflurane in the arterial samples was also determined. Systemic oxygen uptake and vascular resistance were calculated. Isoflurane had no significant effect on systemic oxygen uptake. Significant inverse relationships between blood isoflurane concentration and both mean arterial pressure and systemic vascular resistance were found. It is concluded that isoflurane is a vasodilator under the abnormal conditions of hypothermic cardiopulmonary bypass, but has no effect on systemic oxygen uptake.     

Effect of cardiopulmonary bypass on pulmonary clearance of adrenomedullin in humans

BACKGROUND: Adrenomedullin is a potent vasodilatory peptide and its plasma concentration increases after cardiopulmonary bypass. We analyzed the contribution of the lung to the disposition of adrenomedullin before and after cardiopulmonary bypass in humans. METHODS: Thirty-five patients undergoing cardiac surgery with cardiopulmonary bypass were studied. Bloods were sampled from the pulmonary artery and left atrium at the following times: prior to systemic heparinization, during pulmonary reperfusion and after cardiopulmonary bypass. Plasma concentrations of total and mature adrenomedullin were measured using an immunoradiometric assay kit specific for human adrenomedullin. Intermediate adrenomedullin was calculated as the difference between total adrenomedullin and mature adrenomedullin. RESULTS: Before cardiopulmonary bypass, mature and intermediate adrenomedullin concentrations were reduced by the pulmonary circulation by approximately 30% and 20%, respectively. However, these effects were not observed during pulmonary reperfusion. Mature, but not intermediate, adrenomedullin was reduced after cardiopulmonary bypass. Furthermore, pulmonary clearance quantity of mature adrenomedullin was significantly enhanced after cardiopulmonary bypass. CONCLUSION: These results indicate that cardiopulmonary bypass temporally impairs the pulmonary clearance of mature and intermediate adrenomedullin, but clearance of mature, not intermediate adrenomedullin is enhanced after cardiopulmonary bypass.     

A pulsatile pump for cardiopulmonary bypass and its clinical use

A pulsatile pump driven by a coil spring, which was designed and constructed by us, is described in this report. It consists of two main parts, a disposable blood chamber and a driving section. The blood chamber has two leaflet valves and a piston, which is covered with two bellofram rolling diaphragms and moves into the housing to draw in and eject the blood. The driving section consists of three cams, an electric motor and a coil spring. The ejection force is wholly produced by the compressed coil spring and is transmitted to the piston in the blood chamber by a rod. This pump allows the ejection pressure, the beat rates, and the stroke volume all to be changed independently. The performance of the pump was tested by using a circulation model where the beat rate was adjusted from 30 to 250 bpm. The output subsequently increased from 0.81/min to 5.71/min and the stroke volume, from 20.4 ml to 36.7 ml. This new pump has been used for clinical cardiopulmonary bypasses in 24 patients of open heart surgery and the pressure traces during perfusion resembled those of the patients’ own hearts.     

Indications and problems of coronary artery bypass grafting without cardiopulmonary bypass

As an alternative method of myocardial protection and to obviate the inherent risks of cardiopulmonary bypass (CPB), we have been performing coronary artery bypass grafting (CABG) without CPB in carefully selected patients. Since the first such operation was successfully performed in Junuary 1995 on a patient with angina pectoris and lung cancer, four other patients have subsequently undergone this technique. This series of 5 patients, being 1 man and 4 women ranging in age from 68 to 80 years, is presented in this report. The reasons for the selection of this procedure were concomitant diseases including lung cancer, a calcified aorta, and myocardial infarction. The mean time of ischemia for each anastomosis was 15.3 ± 5.3min, and the maximum cardiac muscle creatine phosphokinase (CPK-MB) was less than 14 unit/l postoperatively. None of the patients required ventilatory support for longer than 24h postoperatively, and oral intake was started within 24h after extubation in all patients. Postoperative angiography confirmed graft patency and none of the patients developed any ischemic symptoms. All the patients were discharged between 1 and 2 months postoperatively. Thus, the off-pump technique is useful when concomitant diseases are present and will become an alternative method of treatment for coronary artery disease in selected patients.     

瑞芬太尼对体外循环患者体循环阻力的影响

Objective To investigate the mechanism by which remifentanil decreases blood pressure during cardiopulmonary bypass (CPB).Methode Twenty-six ASA Ⅱ or Ⅲ patients (NYHA's classification grade Ⅱ or Ⅲ ) of both sexes and aged 20-55 years were randomized to receive remifentanil (group R, n = 13) or normal saline (group C, n = 13). Remifentanil 10 μg/kg or equal volume of normal saline was administered via a venous reservoir when cardiac arrest was induced with cardioplegic solution. The flow rate resistance (SVR) were measured and arterial blood samples were taken for determination of plasma concentrations of histamine,nitric oxide (NO) and 6-keta-prostaglandin F1α(PGF1α) before T0 and at 5, 10, 15 min (T5.10.15) after remifentanil administration.Results Remifentanil administration was associated with a significant decrease in MAP and SVR at T5 and T10 as compared with the baseline values at T0 ( P ＜ 0.05); whereas in control group, MAP and SVR were significantly increased at T5, T10 and T15 as compared with the baseline values at T0 . There were no significant differences in plasma histamine, NO and PGF1α concentrations between the two groups.Conclusion Remifentanil reduces SVR and causes a decrease in BP but without altering plasma concentrations of histamine, NO or PGl2.     

双向Glenn分流术治疗儿童复杂紫绀型先天性心脏病

目的总结双向Glenn(BDG)分流术在治疗儿童复杂紫绀型先天性心脏病(先心病)的经验和体会。方法 1999年1月至2004年10月,对155例具有Fontan术高危因素的复杂先心病作BDG术。高危因素包括:年龄<2岁,左和(或)右肺动脉狭窄,平均肺动脉压升高,房室瓣反流及体静脉或(和)肺静脉异位回流等。术前诊断包括单心室(53例)、右室双出口(44例)、完全性大动脉转位(9例)、纠正性大动脉转位(4例)、三尖瓣闭锁(9例)、肺动脉闭锁伴室间隔完整(11例)、肺动脉闭锁伴室间隔缺损(17 例)、上下心室(7例)和法洛四联症伴完全性房室间隔缺损(1例)。其中56例为内脏异位综合征(HS) (36．1％)。130例和25例分别在体外循环和非体外循环下手术。手术类型包括单侧BDG术(84例),双侧BDG术(52例),下腔静脉-肺动脉外管道BDG术(4例),半Fontan术(13例),右半Fontan术十左BDG 术(2例)。其他手术包括完全性肺静脉(TAPVC)(8例)和部分性肺静脉(3例)异位回流纠治术,房室瓣修复术(12例),肺动脉重建术(26例)。结果术后早期平均动脉氧饱和度由术前0．75±0．07升高至 0．86±0．05。手术早期病死率1．9％(3/155例)。结论 BDG分流术可广泛应用于小儿复杂紫绀型先心病,尤适宜于无法行双室修复术,而又存在Fontan术高危因素病儿。HS手术时,术前诊断有无TAPVC十分重要,在作BDG术同时应行TAPVC纠治术。保留肺动脉前向性血流指征为BDG术后PaO2<30 mm Hg,SaO2<0．75,如SaO2>0．85则部分关闭肺动脉干。就医较晚的10岁以上病儿,行下腔静脉-肺动脉外管道BDG术不失为有效治疗方法。     

Evidence of systemic cytokine release in patients undergoing cardiopulmonary bypass

Cardiopulmonary bypass (CPB) causes a systemic inflammatory response syndrome (SIRS), which can progress to an acute lung inflammation known as postperfusion syndrome. We developed a two-phase hypothesis: first, that SIRS, as indicated by elevated cytokines post-CPB, would be correlated with postoperative pulmonary dysfunction (Phase I), and second, that the cytokine interleukin-6 (IL-6) is predominantly released from the heart in CPB patients (Phase II). Blood samples were collected from patients undergoing CPB for elective cardiac surgery. In seven patients (Phase I), arterial samples were drawn before, during (5 minutes and 60 minutes), and after CPB. In 14 patients (Phase II), samples were collected from the coronary sinus, superior vena cava, and a systemic artery at the times indicated previously. Samples were analyzed with enzyme-linked immunosorbent assay: IL-1, IL-6, IL-8, IL-10, and tumor necrosis factor-alpha were assessed in Phase I and IL-6 assessed in Phase II. In Phase I, IL-6, IL-8, and IL-10 were elevated after CPB, but only IL-6 concentrations correlated with lung function. In summary, Phase I data demonstrate that increased IL-6 levels at the end of CPB correlate with reduced lung function postoperatively. In Phase II, IL-6 elevation was similar at all sample sites suggesting that the heart is not the major source of IL-6 production. We suggest that IL-6 be implemented as a prognostic measure in patient care, and that patients with elevated IL-6 after CPB be targeted for more aggressive anti-inflammatory therapy to protect lung function.