Waschke K, Krieter H, Albrecht D M, van Ackern K, Kuschinsky W
Institut für Anästhesiologie und Operative Intensivmedizin, Fakultät für Klinische Medizin Mannheim, Universität Heidelberg.
Anaesthesist. 1993 Feb;42(2):90-5.
The use of modified haemoglobin solutions as blood substitutes has been investigated extensively during the past decades. Ultrapurified, polymerised bovine haemoglobin (upbHb) is a promising new substance in this respect. It was the aim of the present investigation to study the cardiovascular and respiratory effects of massive blood replacement with upbHb in a new model of conscious rats with continuous haemodynamic monitoring. METHODS. The right femoral artery and vein of 13 male Sprague-Dawley rats were catheterised during halothane-N2O-O2 anaesthesia. A thermistor catheter was placed in the descending aorta via the left femoral artery for measuring cardiac output by the thermodilution method. After recovery from anaesthesia blood replacement was achieved by arterial blood withdrawal and simultaneous venous infusion of upbHb in equal amounts. The haematocrit was lowered to < 3% and the animals were then left undisturbed in a rat restrainer while breathing room air. RESULTS. The animals showed no signs of disturbed behaviour patterns, distress, or adverse reactions. There were no significant changes in cardiac index and oxygen delivery during the investigation period of 4 h. A marked increase in mean arterial pressure (MABP) and systemic vascular resistance (SVR) of 30% was observed while stroke volume remained unchanged. Blood gases, acid-base status, and plasma glucose showed no major changes. Plasma oncotic pressure increased during the investigation period. CONCLUSIONS. The results indicate that there is adequate oxygenation and sufficient systemic oxygen delivery in conscious and drug-free rats after isovolaemic haemodilution with upbHb to a final haematocrit of < 3%. In contrast to previous haemodilution studies, which have tested non-oxygen-carrying solutions, no changes in cardiac index were observed. The cause of the increase in MAP and SVR remains to be established.
在过去几十年中，人们对使用改良血红蛋白溶液作为血液替代品进行了广泛研究。超纯聚合牛血红蛋白（upbHb）在这方面是一种很有前景的新物质。本研究的目的是在一种新的清醒大鼠模型中，通过连续血流动力学监测，研究用upbHb进行大量血液置换对心血管和呼吸系统的影响。方法。在氟烷 - N₂O - O₂麻醉下，对13只雄性Sprague - Dawley大鼠的右股动脉和静脉进行插管。通过左股动脉将热敏电阻导管置于降主动脉，用于通过热稀释法测量心输出量。麻醉恢复后，通过动脉放血并同时静脉输注等量的upbHb来实现血液置换。血细胞比容降至<3%，然后让动物在大鼠约束器中安静休息，同时呼吸室内空气。结果。动物没有表现出行为模式紊乱、痛苦或不良反应的迹象。在4小时的研究期间，心脏指数和氧输送没有显著变化。观察到平均动脉压（MABP）和全身血管阻力（SVR）显著增加30%，而每搏输出量保持不变。血气、酸碱状态和血浆葡萄糖没有明显变化。在研究期间血浆胶体渗透压升高。结论。结果表明，在使用upbHb进行等容血液稀释至最终血细胞比容<3%后，清醒且未用药的大鼠有足够的氧合和充足的全身氧输送。与之前测试非携氧溶液的血液稀释研究不同，未观察到心脏指数的变化。MAP和SVR升高的原因尚待确定。
