洗胃对猪百草枯灌胃模型的清除效果分析

目的 评价不同时间点洗胃(gastric lavage,GL)清除猪胃内百草枯(paraquat,PQ)的效果,以及对血浆PQ浓度的影响.方法 将17头健康雌性家猪按随机数字表法分为PQ组(n=6)、PQ+1 h GL组(n=6)、PQ+6 h GL组(n=5).所有动物按60 mg/kg经胃管注入40％ PQ原液,PQ+1 h GL组和PQ+6 h GL组分别在1h和6h经胃管给予20 L温水单次洗胃,监测生命体征及血药浓度并持续观察24h,LC-MS法测量血浆及HPLC法测量胃洗出液中的百草枯浓度.结果 PQ组、PQ+6 h GL组和PQ +1 h GL组的24 h存活率分别为66.7％、80％、100％;血PQ峰浓度(μg/mL)分别为(5.12±3.38)、(3.99 ± 1.24)、(1.96±1.83);PQ+1hGL组和PQ+6 hGL组洗出液的PQ含量占总摄入量的(24.46±6.49)％vs.(30.72±9.86)％ (P＞0.05);前10 L和后10 L的洗出液中PQ的清除比例:PQ+1 h GL组为(20.44±5.59)％vs.(4.02±1.82)％(P＜0.01),PQ+6 h GL组为(26.17±7.19)％vs.(7.03±4.29)％(P＜0.01).结论 1h和6h洗胃均能有效清除PQ,减少24h病死率;尽早洗胃(1 h)能更明显降低血浆PQ峰浓度;洗胃液在后1/2体积(后10 L洗出液)时清除百草枯的能力明显下降.

Elimination effects of gastric lavage in swine model of paraquat poisoning

Objective To evaluate the elimination effect of gastric lavage (GL) in the swine model of paraquat (PQ) poisoning by using the determination of PQ plasma concentration.Methods A total of 17 healthy female domestic swine were randomly divided into PQ group (n =6),PQ + 1 h GL group (n =6) and PQ + 6 h GL group (n =5).A dose of 60 mg/kg PQ in 40％ PQ solution was administered in all animals through gastric tube.Swine of PQ + 1 h GL group and PQ + 6 h GL group were treated with gastric lavage by using 20 L warm water at 1 h and 6 h after ingestion of PQ,respectively.Vital signs and PQ plasma concentration were monitored continuously for 24 h.LC-MS device was used to measure the PQ concentrations in lavage fluid and plasma,and HPLC was performed to measure the fluid drug concentration.Results The 24 h survival rates of PQ group,PQ + 6 h GL group and PQ + 1 h GL group were 66.7％,80％ and 100％,respectively.The peak plasma PQ concentration in PQ group was (5.12 ± 3.38) μg/mL,in PQ + 6 h GL group was (3.99 ± 1.24) pμg/mL,and in PQ + 1 h GL group was (1.96 ± 1.83) μg/mL.The percentage of the total amount of PQ ingested in the gastric lavage fluid in PQ + 1 h GL group was (24.46 ± 6.49)％ and in PQ + 6 h GL group was (30.72 ± 9.86) ％ (P ＞ 0.05).Alternatively,the gastric lavage process was divided into two successive procedures with 10 L warm water in each instead of 20 L water in one procedure.The content of PQ in lavage fluid from the first 10 L warm water was (20.44 ±5.59)％ and that from the second 10 L warm water was (4.02 ± 1.82)％ in PQ + 1 h GL group (P ＜ 0.01),whereas (26.17 ±7.19)％ PQ in gastric lavage fluid from the first 10 L warm water and (7.03 ± 4.29) ％ PQ in gastric lavage fluid from the second 10 L warm water,in PQ + 6 h GL group (P ＜ 0.01).Conclusions Gastric lavage process carried out in two successive procedures with 10 L warm water in each can eliminate PQ effectively,thus reducing the mortality.The early gastric lavage (1 h) can cause significantly decrease in plasma PQ peak concentration.However,the clearance rate of gastric lavage process is significantly lower in the second procedure in comparison with the first procedure of gastric lavage.