主動脈側接血泵( Para-Aortic Blood Pump，簡稱PABP )為一新穎的左心室輔助器，為了驗證此血泵是否能使血栓和溶血的危機降到最低，本研究共以四種不同的方法進行分析。首先，以粒子標記法觀察其流場軌跡；接著以染料稀釋法驗證PABP血腔中是否會有舊血液殘留；然後以顏料沖刷法研究壁面的沖刷效應；最後應用粒子影像測速法( PIV )使其流場量化。
粒子標記法結果顯示，PABP整體之流場型態大致為單一逆時針渦流；染料稀釋法證明了血腔中之流體經過大約7個週期會完成汰換，此現象可減少血液病變的發生；顏料沖刷法驗證了PABP近壁流場並未發現任何迴流死水區，壁表面皆能被流場均勻地沖刷。
PIV流場量測結果顯示，PABP中心對稱面之流場型態為一逆時針渦流，並且最高的瞬時速度可達100 cm/sec以上。比較其流場、渦度場以及剪應變率場之後，可歸納出：不論心搏率和輔助頻率為何，在PIV所能量測到的特定空間和特定時間範圍中，最快速度以及最大剪應變率皆在剛舒張完成之瞬間；將此時的資料做更進一步之分析，可得到瞬間最大剪應力為0.4 N/m2，此剪應力遠小於紅血球變形剪應力值 50 N/m2以及血小板激化值10 N/m2。綜合以上四種實驗的結果，驗證了PABP之流場產生溶血或血栓之風險是非常低的。

Para-Aortic Blood Pump ( PABP ) is a novel left ventricular assist device. To ensure minimal thrombosis and hemolysis, four methods were used in this study. First, tracer particle visualization was used to reveal basic flow patterns. Second, dye dilution method results can identify if any residual non-replaceable fluid still remained inside the PABP. Third, dye washout method evaluated the surface washing effect. Last, particle image velocimetry (PIV) was applied to quantify the flow fields.
The results of tracer particle visualization showed a counterclockwise vortex pattern inside the blood chamber of PABP. The results of dye dilution method proved good replacement that can prevent blood disease. The results of dye washout method indicated uniform washing on the wall.
The results of PIV also showed a counterclockwise vortex pattern in PABP during diastole, and the maximum velocity was measured near 100 cm/sec. After analyzing the velocity, vorticity, and shear rate fields, one can conclude that both maximum velocity and shear rate happened right in the start of diastole. By calculating strain field of the flow, the maximum instaneous shear stress was found to be 0.4 N/m2, which was far less than the value of erythrocyte deformability: 50 N/m2 and the value of platelet activation: 10 N/m2. Therefore, the current PABP design is proven to be a low risk of thrombosis and hemolysis during diastole.

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