Early postoperative changes with different priming solutions in open-heart surgery

The consequences of substituting dextran 70 (Macrodex) for human plasma in the priming solution were studied during the first 48 hours after open-heart surgery. Twenty patients undergoing elective surgery for coronary artery disease were selected for the study. Clinical, haemodynamic, metabolic and roentgenologic parameters were monitored. No major differences were found between results with use of plasma or dextran (each in 10 patients). The lower pulmonary capillary wedge pressure in the dextran group may indicate better left ventricular performance. As human plasma is a limited resource and is a potential disease transmitter, dextran 70 may with advantage replace human plasma in the priming solution, and at much lower cost.     

Utility of Ringer's acetate solution as an intraoperative fluid during cardiovascular surgery with cardiopulmonary bypass

This study aimed to clarify the difference in the effects of Ringer's acetate (AR) and Ringer's lactate (LR) administration during cardiovascular surgery with cardiopulmonary bypass. We evaluated their effects on intra and postoperative metabolism, liver functions, blood gas and hemodynamic states. Twenty patients were divided into two groups; AR group (n = 10) and LR group (n = 10). Intraoperative serum D-lactate levels in LR group were significantly higher than those in AR group from the beginning of the operation to awakening. Serum acetate levels showed no increase in both groups. The arterial ketone body ratio (AKBR) in AR group was higher than that in LR group, but the difference was not significant. Serum glutamic pyruvic transaminase (GPT) and alkaline phosphatase (ALP) levels in LR group were significantly higher than those in AR group from the induction of the anesthesia. It has been reported that acetate has a greater vasodialatory effect than lactate. However, our findings indicate no significant difference in hemodynamics between the two groups. These results suggest that AR may be more useful than LR during cardiovascular surgery with cardiopulmonary bypass.     

Coronary perfusion and myocardial metabolism during open-heart surgery in man.

Myocardial oxygen consumption and extraction of lactate and free fatty acids (FFA) have been measured in six patients during cardiopulmonary bypass at two coronary flow rates differing by 25 per cent (109 and 148 ml. per minute). Significant differences were found between these flows and between natural and artificial coronary perfusion. This fact indicates the presence of anaerobic metabolism, especially at the lower coronary flow. These findings are discussed in relation to criteria for coronary flow and perfusion pressure during open-heart procedures.     

Duration of cardiopulmonary bypass compared with changes in the plasma protease systems.

Forty patients undergoing elective coronary artery bypass grafting were investigated concerning association between duration of cardiopulmonary bypass (CPB) and changes in the plasma protease systems. Spontaneous enzyme activity, proenzymes and functional inhibition capacities in the fibrinolytic, plasma kallikrein-kinin and coagulation systems were measured before, during and after CPB and in the immediate postoperative period. No clear relationship was revealed between changes in the measured variables and the duration of CPB.     

全麻复合硬膜外麻醉患者林格氏溶液的容量动力学

目的 通过确定全麻复合硬膜外时麻醉林格氏溶液的容量动力学模型参数，评价硬膜外复合全麻对晶体液扩容效应的影响。方法择期行肝癌切除术患者20例，随机分为2组：组Ⅰ麻醉诱导前行扩容治疗，组Ⅱ硬膜外复合全麻诱导后行扩容治疗。扩容采用30ml／kg乳酸钠林格氏溶液（LR）恒速输注，30min内输完，输注LR开始后90min内每5min测定血红蛋白（Hb）及红细胞压积（Hct），并记录总尿量及血液动力学数据。用容量动力学数学模型和物质守恒定律处理数据，获得结果。结果 组Ⅱ容量增加量、容量扩张效率、输注结束时液体保留率均高于组Ⅰ（P〈0．05）。一级容量动力学分析结果：组Ⅰ目标容积（V）和清除率（k1）均大于组Ⅱ（P〈0．05）。二级容量动力学分析结果：组Ⅱ的V1、k1、k1均高于组Ⅱ（P〈0．05）。扩容后组Ⅱ的平均动脉压、中心静脉压、心输出量均小于组Ⅰ（P〈0．05）。结论 全麻复合硬膜外麻醉可提高晶体液的容量扩张效率。     

Changes in red cell deformability associated with anaesthesia and cardiopulmonary bypass in open-heart surgery

Red cell deformability was observed during open-heart surgery in 59 patients. Deformability, assessed with a standard microfiltration method, was expressed as red cell filtration rate (RFR) in microliter/s. The mean preoperative value, 38.9 +/- 1.0 microliter/s, showed a generally falling tendency. The first significant decrease in mean RFR (by 18%) followed induction of general anaesthesia, and the second (by 15%) was seen 60 min after the start of cardiopulmonary bypass (CPB). The major decrease in RFR during CPB was found at the end of bypass, when it was reduced to 62% of the pre-CPB value. The percentage RFR reduction at the end of CPB showed significant correlation with 1) CPB duration (r = 0.49), 2) oxygen flow rate index (OFRI), i.e. flow/min in the bubble oxygenator/m2 bsa (r = 0.38), and 3) blood flow rate index (BFRI), i.e. average volume of blood pumped through the heart-lung machine/min CPB time/m2 bsa (r = 0.51).     

Carbon dioxide in the prevention of air embolism during open-heart surgery

The factors which are important in the design and use of apparatus for the effective displacement of air by carbon dioxide from chest cavities are examined. High levels of carbon dioxide can be achieved by flowing carbon dioxide at a total flow rate of 51./min. into the chest cavity through two nozzles of 0·5 to 1·0 cm. diameter. The effect of factors which might diminish the carbon dioxide levels is examined.     

羟乙基淀粉130/0.4预充液对围体外循环期患儿血管内皮细胞及血管通透性的影响

目的探讨羟乙基淀粉130／0．4预充液对先天性心脏病患儿围体外循环期血管内皮细胞(VEC)及血管通透性的影响。方法择期体外循环(CPB)下行心内直视手术的先天性心脏病患儿40例,ASAⅡ或Ⅲ级,男19例,女21例,年龄5～18岁,随机分为2组(n=20):血浆组(对照组)和羟乙基淀粉130／0．4组(试验组)。对照组预充乳酸林格氏液和血浆,试验组预充乳酸林格氏液和羟乙基淀粉130／0．4。胶体预充液用量18-33 m1·kg-1,晶体:胶体=0．60-0．70。分别于转流前即刻(T1)、转流30min(T2)、转流结束即刻(T3)、转流结束6 h(T4)、术后第1天清晨(T5)检测血浆循环内皮细胞(CEC)数量、内毒素、可溶性细胞间粘附分子-1(sICAM-1)、肿瘤坏死因子-α(TNF-α)及尿微量白蛋白(U-Mal)浓度。结果．T1时两组CEC、内毒素、sICAM-1、TNF-α、U-Mal差异无统计学意义(P>0．05)。CEC:两组T2、T3及T4时较T1增高,T4时试验组低于对照组(P<0．05)。内毒素:两组T2、T3、T4时较T1升高,T3、T4、T5时试验组低于对照组(P<0．05)。sICAM-1:对照组T4、T5时较T1升高,T4时试验组低于对照组(P<0．05)。TNF-α:对照组T3时较T1升高,试验组低于对照组(P<0．05)。U-Mal:两组T4时较T1升高,试验组低于对照组(P<0．05)。结论羟乙基淀粉130／0．4预充液对先天性心脏病患儿围体外循环期VEC及其功能具有保护作用。