犬海水淹溺后支气管肺泡液细菌学分析

目的通过比较犬海水与淡水入肺后支气管肺泡液的细菌学分析,探讨南海海域海水淹溺后动物肺部感染的病原学特征。方法 12只健康犬随机分为海水组6只,淡水组6只。参照Modoll方法灌注海水或淡水（灭菌注射用水）,分别于灌注后即刻、4 h、8 h、12 h、24 h、36 h、48 h以纤维支气管镜在无菌操作下提取支气管肺泡液做细菌培养,并于48 h后取肺组织送细菌定量培养。结果海水组动物灌注海水后立即提取的支气管肺泡液,只能培养出少量菌种或无培养结果,4 h后各时相点可检出的菌种开始增加,分离的病原微生物以革兰阴性（G-）菌为主,占57%,革兰阳性（G＋）菌占39%。真菌占4%。淡水组灌注后即刻、4 h所提取的支气管肺泡液培养出少量菌种,24 h后菌量增加,菌量低于海水组。其检出的菌种和菌株与海水组无统计学差异：G-菌占58%,G＋菌占38%,真菌占4%。两组支气管肺泡液培养中均未发现海水中特有的嗜盐菌群。海水组动物在48 h后肺组织细菌定量达（5.473±1.211）×105 cfu/g,已超过组织感染的临界指标（105 cfu/g）,淡水组则仅为（3.201±1.035）×104 cfu/g,显著低于海水组（P〈0.05）。结论海水淹溺后,海水对肺组织的损伤较淡水淹溺重,而早期肺部感染的菌株及菌种和犬体的细菌相关,和海水嗜盐菌无相关。

Bacteriological Analysis of Bronchoalveolar Fluid of Dogs after Drowning in Seawater

Objective To perform the bacteriological analysis of bronchoalveolar fluid of dogs with seawater or freshwater in the lung and explore the pathogenic characteristics of lung infection of animals after drowning in Souch China sea water. Methods A total of 12 mongrel dogs were randomly divided into seawater group(group A,6 dogs) and freshwater group(group B,6 dogs).The two groups were perfused by seawater or freshwater by Modell method.Bronchoalveolar fluid was extracted by bronchoscope under aseptic condition immediately and at 4,8,12,24,36,48 hours after water perfusion.Lung tissues were collected for bacterial culture at 48 hours. Results In group A,there was no or only a small quantity of bacterial strains cultured in the bronchoalveolar fluids immediately after seawater perfusion.The bacterial strains were increased after 4 hours,mainly Gram negative bacillus(57%),Gram positive bacillus(39%),and fungus(4%).In group B,a few bacterial strains were cultured immediately and at 4 hours after perfusion.The bacterial strains were increased after 24 hours,and lower than those of group A.There was no difference in the kinds of bacterial strains in group B(Gram negative bacteria for 58%,Gram positive bacteria for 38%,and funguns for 4%) compared with group A.No seawater-specic halophilic bacterias were founded in the two groups.The bacterial quantity in the lung tissue of group A was(5.473±1.211)×105 cfu/g which was significantly higher than the bacterial infection index(105 cfu/g) and(3.201±1.035)×104cfu/g in group B. Conclusion The lung injuries are more serious after seawater drowning than that after freshwater drowning.The bacterial strains causing early lung infection are related with those of dogs’ bodies and not obviously related with seawater-specic halophilic bacterias.