胃液与盐酸误吸导致大鼠肺损伤的对比性研究

Lung injury induced by aspiration of gastric juice or hydrochloric acid

在定压式人工呼吸下,分别经气管给大鼠肺内注入胃液(pH=1.5)和相同pH值的盐酸3.0ml/kg,然后用纯氧持续通气3小时。结果:误吸后胃液组的PaO_2由60kPa左右下降至14kPa以下,而盐酸组仅下降至30kPa左右(P<0.01)。胃液组的PaCO_2与盐酸组相比上升速度快,幅度高(P<0.05)。胃液组pH的下降幅度明显大干盐酸组(P<0.01)。8只胃液组大鼠有5只在3小时内因乏氧、酸中毒等休克死亡,而盐酸组无一例死亡。胃液组肺灌洗液中的蛋白浓度和红细胞数明显高于盐酸组,以上结果表明,由胃液引起的误吸对肺组织的损伤远远大于单纯盐酸的误吸。

In order to compare lung damage induced by aspiration of gastric juice or hydrochloric acid (HC1), sixteen adult rats were ventilated with pure oxygen (PIP 2.0 kPa, PEEP 0.5kPa). and ran domly divided into group G and group H. The rats in group G received intratracheal instillation of 3ml/kg gastric juice with a pH 1.5 and those in group H were given HC1 at the same volume and pH. Results showed that after aspiration, the PaO_2 decreased rapidly from 60 kPa to 14 kPa in group G and to 30 kPa in group H (P<0.01). The pH of arterial blood decreased in both groups, but more significant in group G (P<0.05). The PaCO_2 increased after aspiration, but faster in group G (P<0.05). Five of 8 rats in group G died of anoxemia and acidosis in 3 hours, whereas none of rats in group H died. The albumin concentration and RBC in bronchoalveolar lavage fluid from group G were much higher than those from group H. These results suggest that the lung damage induced by aspiration of gastric juice is much severer than that by aspiration of HC1.