高原胸部火器伤后TXB_2和6-keto-PGF_1α含量的变化及其意义

Changes and significance of TXB_2 and 6-keto-PGF_1α contents in dogs with chest firearm injury at high altitude

目的探讨高原胸部火器伤早期血浆及肺组织血栓素B2(TXB2)和6-酮-前列腺素F1α(6-keto-PGF1α)的变化及其意义。方法 18只体重相近(10～15 kg)的健康杂种犬,随机分成3组(每组6只):平原伤前组、平原对照组和高原移居组,另外6只高原杂种犬作为高原世居组。平原对照组实验海拔高度为500 m,高原组实验海拔高度为3700 m。实验动物用3%戊巴比妥钠静脉麻醉(30 mg/kg)后,用0.44 g钢珠以400 m/s的初速度从右第6肋间射入,造成右胸贯通伤,伤后立即封闭伤口,安放胸腔闭式引流。各组分别在伤后2、4、6、8、12 h通过中心静脉插管抽取血标本,伤后12 h取双侧肺组织,检测血和肺组织内的TXB2和6-keto-PGF1α含量。结果各组伤后血浆6-keto-PGF1α和TXB2均明显升高,而TXB2和6-keto-PGF1α的比值仅高原移居组在伤后6 h开始有明显升高。各组伤侧肺组织的TXB2/6-keto-PGF1α比值都比平原伤前组明显增高,尤以高原移居组最为明显;但是,健侧肺组织TXB2/6-keto-PGF1α的比值仅高原移居组显著升高,其他组无显著差异。结论高原世居组和平原对照组在胸部火器伤后,肺组织水肿主要局限在伤侧;而高原移居组在胸部火器伤后早期,不论是伤侧还是健侧肺,均存在发生水肿的风险,在伤后应积极预防肺水肿的发生。

Objective To explore the changes and significance of thromboxane B2（TXB2） and 6-keto-PGF1α contents in the plasma and lung tissue of dogs with early chest firearm injury at high altitude.Methods 18 healthy mongrel dogs（10-15 kg） in plain were randomly divided into three groups（n=6）：plain pre-injury group,plain control group and high altitude immigrant group.Other six native mongrel dogs at high altitude were used as high altitude native group.The right chests of the anesthetized dogs at high altitude（3700 m above sea level） or in plain（500 m above sea level） were shot from the 6th right intercostal space with steel balls of 0.44 g at a speed of 400 m/s.The perforating wounds were closed instantly,and then the animals were given thoracic closed drainage.The blood samples were collected via central vein catheter before injury and at 2,4,6,8,12 h after injury and bilateral lung tissues were obtained at 12 h after injury in each group.Then TXB2 and 6-keto-PGF1α contents in blood samples and lung tissues were determined.Results The plasma contents of TXB2 and 6-keto-PGF1α increased significantly in each injured group,but the ratio of TXB2/6-keto-PGF1α rose significantly only in high altitude immigrant group from 6 h after injury.The ratio of TXB2/6-keto-PGF1 α at injured side of lung tissue increased significantly in three injured groups,especially in high altitude immigrant group,compared with plain pre-injury group.Nevertheless,this ratio at uninjured side of lung tissue rose significantly only in high altitude immigrant group,while other groups showed no significant differences.Conclusion Pulmonary edema in plain control dogs and high altitude native dogs is mainly limited at injured side lung after chest firearm injury.However,high altitude migrated dogs appear to have the risk of pulmonary edema in the early stage of chest firearm injury whenever at injured side or uninjured side.Therefore,the effective methods should be taken to prevent the occurrence of pulmonary edema after chest firearm injury.