以非侵入脈波傳遞時間來偵測PROPOFOL引發之動態血管擴張

Abstract

麻醉可在手術過程中提供止痛，肌肉鬆弛，昏迷。異丙酚(propofol)是是常使用的麻醉劑，但不可避免的會使血管擴張。當血管擴張過多或無法忍受時，會導致在一些危重病人致命的後果。目前有許多方法用於檢測血管擴張的方法，但他們是侵入性的。在這篇論文中，我們提出了一個模型：一個非侵入性的方法，利用脈搏波傳導時間檢測異丙酚所引起的動力學血管擴張。 PTT (pulse transit time)是脈衝波的傳遞時間，這期間，是表示在同一心動週期的兩個動脈部位之間傳播。這項研究是使用PTT來測量異丙酚對血管系統的影響。我們收集的數據，從70名健康婦女，年紀28-51年歲，在全身麻醉下進行婦科手術。全身麻醉誘導異丙酚注射液（2mg/kg）。ＰＴＴ的測量是從 R波心電圖和到食指的脈搏波（photoplethysmograph）。量測兩個 PTT值：注射前和注射異丙酚後，以 student’s t -test結果進行分析。結果: 異丙酚注射後，PTT延長，且其前後的變化統計學意義。 （P <0.05）。PTT的改變與血管擴張的程度相似。 PTT的監測發現不僅可以偵測血管的變化幅度，也可以顯示其峰值和藥物作用時間。將異丙酚放入我們的模型，我們得出結論 PTT是一個可以放入監測異丙酚的藥物動力學模型。 未來可以利用PTT量測出健康人的數值在。再和利用熱稀釋方式所量測血管動力學的數值做比較，建立ＰＴＴ更準確地用在病人身上。也可以用在不同藥物對血管的影響或治療

Anesthesia offers pain relief, muscle relaxation and unconsciousness during surgery. Propofol is the one of the most common used among the anesthetic agents but it results in unavoidable vasodilatation which may lead to lethal consequences in hemodynamically unstable patients. Many methods have been used to detect the complication but they are all invasive. In this thesis, we propose a non invasive method using pulse wave transit time to detect propofol-induced vasodilatation. PTT is the duration of time during which a pulse wave travels between two arterial sites within the same cardiac cycle. It is used to examine propofol’s effects on vascular system. Methods. Data is collected from 70 healthy women, between 28 to 51years old, receiving gynecological surgery under general anesthesia. The general anesthesia was induced with propofol injection (2mg/kg). PTT measurements were obtained from the R wave of electrocardiogram and pulse wave of photoplethysmograph. Two PTT values were obtained; one before (the control) and the other after propofol injection. The results were analyzed by Student's T-test. Results. After propofol injection, the PTT was prolonged. The change of the PTT value from that of baseline was significant statistically. (P<0.05, by Student’s T-test). The PTT change over time correlated with the degree of vasodilatation over time. PTT monitoring revealed not only the magnitude of vascular changes but also demonstrated the onset of vascular dilation, its peak and duration. We therefore conclude that PTT is a useful guide in monitoring the phamocokinetics of propofol.