兔体外循环中聚乙二醇牛血红蛋白偶联物对平均动脉压、胶体渗透压及p50的影响

Effect of PEG-conjugated bovine hemoglobin on mean arterial pressure,colloid osmotic pressure and p50 during cardiopulmonary bypass in rabbits

目的探讨在体外循环(CPB)预充液中加入聚乙二醇牛血红蛋白偶联物(PEG-bHb)对兔平均动脉压(MAP)、胶体渗透压(COP)及p50的影响。方法24只成年健康大耳白兔(2．59±0．19)kg,通过股动脉、颈静脉插管建立体外循环通路,转流1h。随机分成3组,对照组(n =8),以晶／胶体液作为体外循环预充液；实验组1(n=8),在预充液中加入PEG-bHb,PEG-bHb占总容量(兔循环血量+预充量)的5％；实验组2(n=8),预充液中加入PEG-bHb,占总容量(兔循环血量+预充量)的15％,体外循环开始后放出自体血(放血量占兔循环血量的20％),CPB结束后将自体血回输。每组监测CPB前和CPB中平均动脉压；在CPB前、CPB中15、50 min、CPB后1 h测胶体渗透压及动脉血p50值。结果实验组1和实验组2在CPB中的MAP均高于对照组,但只有实验组2在转中10 min时与对照组相比差异有统计学意义(P＜0．05)；实验组2在CPB中COP值均较高；实验组1动脉血p50值较对照组高。结论PEG-bHb占实验兔循环血量+预充量的5％对CPB中和CPB后MAP和COP无明显影响,并且由p50提示向组织释放O_2量增多,此量可安全用于CPB预充；另外,在CPB前放出部分自体血将对CPB中血液保护发挥一定作用。

Objective To investigate the effect of PEG-conjugated bovine hemoglobin （PEG- bHb） on mean arterial pressure, colloid osmotic pressure （COP） and p50 when added direcdy to CPB prime in anaesthetized rabbits. Methods Twenty-four anaesthetized rabbits, （2.59 ± 0.19） kg,connected to CPB by jugular venous and femoral arterial cannulaton for 1 h,were randomly divided into 3 groups. In control group （ n = 8）, a crystalloid/colloid solution was used as prime solution. In experimental group 1 （n = 8）,PEG-bHb （5 % total volume） was used in the pump prime of bypass （Total volume was the sum of circulation volume and prime volume）. In experimental group 2 （n = 8）, PEG-bHb （15 % total volume） was used in the pump prime with previous blood harvesting （20% circulation volume） before CPB. MAP, COP and p50 were monitored throughout the procedure. Results A significant increase in MAP pressure （P 〈 0.05） was shown in experimental group 2,10 min of CPB as compared with control group. COP in experimental group 2 during CPB was higher. P50 in experimental group 1 during CPB was higher than that in control group. Conclusion PEG-bHb （5 % total volume） is well tolerated used in the pump prime of bypass.