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兩種血管通路中血流特性及其對(duì)管壁影響的數(shù)值模擬研究

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【摘要】:深入理解血液流動(dòng)的特性及血管的響應(yīng)對(duì)于相關(guān)治療方案的改進(jìn)和選取至關(guān)重要。由于血液流動(dòng)的復(fù)雜性及活體實(shí)驗(yàn)的困難,目前在這方面的研究成果尚不能滿足臨床需求。本文結(jié)合動(dòng)靜脈內(nèi)瘺和深靜脈留置導(dǎo)管這兩種常見的手術(shù)在此方面開展了數(shù)值模擬研究。在腎功能衰竭晚期,接受血液透析治療是患者維持生存的重要手段,而良好的血管通路是血液透析治療成功的關(guān)鍵。一般來說,自體動(dòng)靜脈內(nèi)瘺是最佳的血管通道,但動(dòng)靜脈內(nèi)瘺改變了原來的血液流動(dòng),可能會(huì)引起血管壁內(nèi)膜增生。本文采用有限體積法,并考慮了血液的非牛頓流體性質(zhì)以及血流的非定常性,在血管壁剛性無滑移的假設(shè)下,對(duì)自體動(dòng)靜脈內(nèi)瘺對(duì)血流的影響進(jìn)行了數(shù)值模擬。模擬結(jié)果表明:內(nèi)瘺部分出現(xiàn)了一個(gè)比較復(fù)雜的渦流,導(dǎo)致內(nèi)瘺附近的靜脈壁面剪切力的最小值很小;距內(nèi)瘺越近,截面上的壁面剪切力分布的不均勻程度越大,血管的穩(wěn)定性越低,這很可能是導(dǎo)致動(dòng)靜脈瘺口吻合處?kù)o脈內(nèi)膜增生的一個(gè)重要原因。某些高齡或心功能不全的患者,因其血管的條件較差,不能建立動(dòng)靜脈內(nèi)瘺或者患者不能耐受內(nèi)瘺。對(duì)于此類患者可考慮采用長(zhǎng)期深靜脈留置導(dǎo)管,然而血流不暢或內(nèi)膜增生同樣可能導(dǎo)致導(dǎo)管功能失效。本文對(duì)置入導(dǎo)管的靜脈段的血流進(jìn)行了數(shù)值模擬,結(jié)果表明:在導(dǎo)管側(cè)孔處,血管壁上的壁面剪切力的分布不均勻。結(jié)合其他學(xué)者的研究成果,可推測(cè)剪切力的不均勻分布對(duì)血管內(nèi)膜增生有重要影響。
[Abstract]:An in-depth understanding of the characteristics of blood flow and the response of blood vessels is essential to the improvement and selection of treatment protocols. Due to the complexity of blood flow and the difficulty of in vivo experiments, the current research results in this field can not meet the clinical needs. Combined with arteriovenous fistula and deep vein indwelling catheter, numerical simulation was carried out in this paper. In the late stage of renal failure, hemodialysis is an important means to maintain the survival of patients, and good vascular access is the key to successful hemodialysis treatment. In general, autogenous arteriovenous fistula is the best vascular channel, but arteriovenous fistula changes the original blood flow and may cause intimal hyperplasia. In this paper, the influence of autogenous arteriovenous fistula on blood flow was numerically simulated under the assumption of rigid vessel wall and no slip, taking into account the non-Newtonian fluid properties of blood and the unsteady flow of blood flow by using the finite volume method. The simulation results show that there is a complicated eddy current in the internal fistula which results in the minimal shear stress of the venous wall near the internal fistula. The closer to the internal fistula, the greater the uneven distribution of shear force on the wall of the section, and the lower the stability of the blood vessel, which may be an important reason for the intimal hyperplasia of the vein at the anastomosing position of the arteriovenous fistula. Some patients with advanced age or heart failure can not establish arteriovenous fistula or can not tolerate internal fistula because of their poor vascular conditions. Long-term deep venous catheterization may be considered for such patients, but poor blood flow or intimal hyperplasia may also lead to catheter failure. In this paper, the blood flow in the vein segment of the catheter is simulated. The results show that the shear force on the wall of the vessel wall is not evenly distributed at the lateral orifice of the catheter. Combined with the research results of other scholars, it can be inferred that the uneven distribution of shear stress plays an important role in intimal hyperplasia.
【學(xué)位授予單位】:天津大學(xué)
【學(xué)位級(jí)別】:碩士
【學(xué)位授予年份】:2014
【分類號(hào)】:R692.5;O35

【參考文獻(xiàn)】

相關(guān)期刊論文 前6條

1 王葳;姜燕;王巍巍;陸石;張金元;;血液透析患者動(dòng)靜脈內(nèi)瘺狹窄的機(jī)制研究與防治進(jìn)展[J];中國(guó)血液凈化;2012年10期

2 符霞;劉相富;鐘海英;邱碧輝;梁馨苓;劉敏芬;溫建霞;葉錫蘭;;內(nèi)瘺穿刺方向?qū)ψ泽w動(dòng)靜脈內(nèi)瘺功能的影響[J];護(hù)理學(xué)雜志;2012年17期

3 杜春玲;;維持性血液透析患者動(dòng)靜脈內(nèi)瘺失功的原因分析及護(hù)理[J];實(shí)用醫(yī)學(xué)雜志;2010年10期

4 葉朝陽,付文成,戎殳,陳靜,馬曉紅,張斌,梅長(zhǎng)林;長(zhǎng)期深靜脈留置雙腔導(dǎo)管血液透析的臨床應(yīng)用[J];腎臟病與透析腎移植雜志;2004年03期

5 王彤,谷傳綱,楊波,黃建德;非定常流動(dòng)計(jì)算的PISO算法[J];水動(dòng)力學(xué)研究與進(jìn)展(A輯);2003年02期

6 弓偉;范靜東;佟峰;葉朝陽;;長(zhǎng)期留置導(dǎo)管與動(dòng)靜脈內(nèi)瘺對(duì)長(zhǎng)期血液透析患者生存質(zhì)量評(píng)估的對(duì)比觀察[J];中國(guó)醫(yī)師進(jìn)修雜志;2010年18期

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