本文選題：肺沖擊傷　切入點：幼兔　出處：《第三軍醫(yī)大學》2016年碩士論文

【摘要】：研究背景和目的在現(xiàn)代戰(zhàn)爭中,隨著高爆武器的研發(fā)進展及恐怖活動的日益猖獗,爆炸傷的發(fā)生率和死亡率不斷上升。肺是爆炸傷產(chǎn)生的沖擊波的主要靶器官,也是造成傷員死亡的主要原因。其中兒童受到爆炸傷的案例各種媒體也多有報道。嬰幼兒的肺等器官尚未完全發(fā)育完善,其生物力學特點、損傷機制和傷后病理生理機制與成年的肺等有顯著的差異。其中差異最大的要數(shù)肺表面活性物質(zhì)(pulmonary surfactant,PS)的合成與分泌。PS是分布于肺泡內(nèi)氣液表面,主要由肺泡Ⅱ型上皮細胞(alveolar type II epithelial cells,AT-II)合成和分泌的一種脂蛋白復合物。PS的構(gòu)成中磷脂所占比例約為90%,包括飽和磷脂酰膽堿(DSPC)、磷脂酰甘油(PG)等50余種;肺表面活性蛋白(surfactant protein,SP)所占比例約為10%,目前發(fā)現(xiàn)主要包括SP-A、B、C、D四種。在肺泡Ⅱ型細胞中的磷脂循環(huán)利用、調(diào)控對于外界刺激或感染而引發(fā)的炎癥反應、參與PS分子膜結(jié)構(gòu)的合成與穩(wěn)定及抑制肺纖維化等方面具有重要作用。因此爆炸沖擊傷所導致的未成熟肺沖擊傷傷情特點與救治需求也與成年人有較大差異;尚未完全發(fā)育成熟肺的沖擊傷研究,有助于深入認識肺沖擊傷的機制、病理生理與救治(如表面活性物質(zhì)在其中的作用)。以往的研究大都是針對成熟肺臟,針對未成熟肺沖擊傷的損傷特點、救治及轉(zhuǎn)歸的研究報道較少。為此,我們特別建立了一種幼兔重度肺沖擊傷動物模型,并與成年兔進行比較,明確未成熟肺沖擊傷的疾病特點和救治關(guān)鍵,進一步驗證PS在沖擊傷過程中的重要作用及相關(guān)機制。第一部分:幼兔重度肺沖擊傷動物模型的建立研究目的建立穩(wěn)定的幼兔重度肺沖擊傷實驗動物模型,為未成熟肺沖擊傷機制和肺損傷救治研究提供理想的動物模型。資料和方法致傷驅(qū)動壓初篩:選取4周齡新西蘭白兔16只,隨機分為驅(qū)動壓4.0 MPa組和4.5mpa組,采用bst-Ⅰ型生物激波管,以相應的驅(qū)動壓力致傷,對比2組肺沖擊傷傷情。肺沖擊傷傷情特點觀察:選取4周齡新西蘭白兔48只,隨機分為正常對照組(8只)和沖擊傷組(40只),依前面研究結(jié)果,沖擊傷組采用4.5mpa驅(qū)動壓進行致傷;分別于傷即刻(0h)、2h、4h、6h、12h、24h、48h及72h觀測動物生命體征和生理指標、肺大體解剖和光鏡病理、測定肺組織含水量等。研究結(jié)果致傷驅(qū)動壓初篩:2組動物均存活,4.0mpa組沖擊波超壓為(328.16±4.78)kpa,重度肺沖擊傷率為12.5%,ais評分(3.38±0.52)分;4.5mpa組沖擊波超壓為(395.04±11.74)kpa,重度肺沖擊傷率為87.5%,ais評分(4.13±0.64)分。肺沖擊傷傷情特點觀察:致傷動物均存活,傷后即刻出現(xiàn)持續(xù)約0.5h的精神萎靡等情況,隨后動物呼吸和心率等加快,肺臟出現(xiàn)廣泛片狀出血和水腫,肺含水量顯著增加,多為重度沖擊傷,ais評分(3.98±0.55)分,肺光鏡病理以肺組織斷裂、出血、水腫,伴炎細胞浸潤為主。結(jié)論利用bst-Ⅰ型生物激波管,采用4.5mpa驅(qū)動壓可建立穩(wěn)定的4周齡新西蘭白兔重度沖擊傷模型,此模型傷情穩(wěn)定,可用于未成熟肺沖擊傷機制和肺損傷救治的實驗研究模型。第二部分:幼年兔與成年兔重度肺沖擊傷的病理生理特點和其sp-b的變化與作用研究目的比較相同傷情條件下幼年兔與成年兔重度肺沖擊傷的疾病變化特點,探討ps在肺重度沖擊傷病理過程中的作用及機制。資料和方法選取成年新西蘭白兔40只,4周齡新西蘭白兔40只,采用bst-Ⅰ型生物激波管,以4.0mpa和4.5mpa驅(qū)動壓力致傷,記錄沖擊波參數(shù),對比2組肺沖擊傷傷情,并于傷后0.5h、2h、4h、6h、12h、24h、48h及72h觀測動物生命體征和生理指標、肺大體解剖和光鏡病理、測定肺組織含水量、血氣分析、血常規(guī)檢測及sp-b含量等。研究結(jié)果由BST-Ⅰ型生物激波管在相同驅(qū)動壓力下所產(chǎn)生的致傷沖擊波在壓力峰值和持續(xù)時間數(shù)值較為穩(wěn)定,幼年組重度肺沖擊傷占92.5%,AIS評分(4.12±0.74)分,肺出現(xiàn)面積(40.25±6.78)%;成年兔組重度肺沖擊傷占90%,AIS評分(4.03±0.65)分,肺出血面積(38.95±8.33)%,兩組間無明顯差異(P0.05),傷情較為一致可進行比較。幼年兔組肺含水率(81.32±1.71)%高于成年兔組肺含水率(80.20±1.27)%(P0.01),但其于傷后12h便基本恢復至正常水平,快于成年兔的24h。幼年兔組中性粒細胞百分比于致傷后2-4小時左右達到高峰,并于6-12小時恢復正常;成年兔組則于致傷后4-6小時左右達到高峰,至24-48小時才恢復,且成年兔的峰值明顯高于幼年兔,其炎癥反應較幼年兔程度更重,持續(xù)時間更長。幼年兔SP-B含量(OD值0.3638±0.0546)明顯低于成年兔(OD值0.4569±0.0314),且于致傷后迅速降低在4-6小時左右達到最低,下降速度較成年兔快,且恢復較成年兔慢,幼年兔PS合成及分泌功能較成年兔明顯不足。盡管成年兔炎癥反應及肺水腫程度較重,但由于幼年兔PS水平低下,評價呼吸功能的血樣飽和度仍較幼年兔組恢復較快,PS在減少肺泡張力、維持呼吸膜穩(wěn)定、保障呼吸功能中有著重要作用。結(jié)論4.0MPa驅(qū)動壓力沖擊波致傷的成年兔與4.5MPa驅(qū)動壓力沖擊波致傷的幼年兔傷情較為一致,可進行同傷情條件下成年兔與幼年兔沖擊傷病理生理變化特點的比較。通過此比較,明確了在重度肺沖擊傷中幼年兔較成年兔肺水腫恢復較快、炎癥反應較輕;但因PS含量較低,其合成和分泌功能較弱,呼吸功能恢復較慢,證實了PS的不足在傷后肺泡張力恢復、維持肺泡內(nèi)氣液界面穩(wěn)定、通氣和換氣功能的恢復中具有重要作用。
[Abstract]:Background and purpose in the modern war, along with the increasingly rampant development of high explosive weapons and terrorist activities, the incidence and mortality of blast injury is increasing. The lung is a major target organ of explosive shock wave produced, but also the main cause of death among children. The wounded by the blast injury cases of various media many of them have been reported. The infant lung has not been fully developed, its biomechanical characteristics, mechanism of injury and injury pathophysiology and adult lung are significantly different. The biggest difference to the number of lung surface active substances (pulmonary, surfactant, PS) and the synthesis and secretion of.PS is distributed in the alveolar gas the surface is mainly composed of type II alveolar epithelial cells (alveolar type II epithelial cells, AT-II) phospholipid synthesis and secretion of a complex lipoprotein.PS in the proportion of about 90%, including full And phosphatidylcholine (DSPC), phosphatidylglycerol (PG) of more than 50 kinds; pulmonary surfactant protein (surfactant, protein, SP) accounted for about 10%, it is mainly including SP-A, B, C, D. Four kinds of phospholipid recycling in alveolar type II cells in the regulation of inflammatory response caused to outside stimulation or infection, and plays an important role in inhibiting pulmonary fibrosis and other aspects involved in the synthesis and stabilization of PS molecular film structure. So the blast injury caused by the immature lung blast injury characteristics and treatment needs are quite different from adults; not yet complete study of impact injury in all mature lung, help for understanding the mechanism of lung impact injury, pathophysiology and treatment (such as surfactant in the role). Most of the previous studies on lung injury characteristics in mature, immature lung blast injury, treatment and research reports to the less. This, we established a rabbit animal model of severe lung blast injury, and compared with the adult rabbit, disease characteristics and treatment key clear immature lung blast injury, to further verify the role of PS in the process of blast injury and the related mechanism. The first part: to establish a rabbit animal model of severe lung blast injury objective to establish a stable rabbit pulmonary blast injury in experimental animal models, to provide an ideal animal model for the mechanism of injury of lung injury and treatment of shock. Materials and methods immature lung injury driving pressure screening: 16 4 week old New Zealand white rabbits were selected and randomly divided into driving pressure of 4 MPa group and 4.5MPa group using bst-, the effects of a biological shock tube, the pressure to drive the corresponding injury, compared 2 groups of pulmonary blast injury. Pulmonary blast injury observed: 48 4 week old New Zealand rabbits were selected and randomly divided into normal control group (8 rats) and impact 浼ょ粍(40鍙，

本文編號：1675894