实验性高乳酸血症家兔心电图动态变化

Dynamic changes in electrocardiogram of rabbits with experimental hyperlacticemia

为了解高乳酸血症对家兔心肌电生理的影响,将8.5％乳酸溶液0.3ml/kg体重在5min(缓注组,n=20)与45s(急注组,n=4)内分别注入家兔静脉内,作注射前后心电图动态变化自身对照。结果(1)慢注组注入后10、20、30min时心率减慢(P<0.05),R波电压降低(P<0.05),QRS时限增宽(P<0.05)。(2)急注组注入后心率变慢,T波双相、倒置或低平,出现房室及室内传导阻滞。提示高浓度乳酸对心肌自律性和传导性均有明显抑制作用,并使心肌受损。

We injected 8. 5% lactic acid solution (0, 3ml/kg body weight) into veins of rabbits in 5 minutes in slow injection group ( n = 20) and in 45 seconds in rapid injection group(n=4), and then observed their dynamic changes in electrocardiogram before and after injection for comparison. Results in our experiment were as follows : (1) Heart rate in slow injection group decreased ( P<0. 05), R waves voltages lowered (P<0. 05), and QRS complexes widened ( P<0. 05) at 10th, 20th, and 30th minute after injection. (2) Heart rates also decreased, T waves showed double or inverse direction or lowered, and atrioventricle and intraventri-cal conduction blockage occurred after injection in rapid injection group. Our results indicated that highly concentrated lactic acid solution might inhibit autorhyth-micity and conductibility of myocardium and do damage myocardium.