全身麻醉過程中脈波傳導速率與血循動力學參數的系列變化及其相關性

Serial Changes of Pulse Wave Velocity and Correlations with Hemodynamic Parameters during General Anesthesia

背景：脈波傳導速率的增加為動脈硬化的指標，也証實與動脈血壓有正相關性，但在全身麻醉及手術刺激下的變化則不清楚。本研究的目的是，對於接受婦科手術的婦女，於全身麻醉下連續記錄其脈波傳導速率、血壓與心跳的變化，並分析其相關性。方法：以雙通道光容積變化圖的量測，脈波傳導速率可由手指腳趾間距離除以脈波傳遞時間計算而得。脈波傳導速率、血壓和心跳數值在麻醉的前、中、後皆予完整記錄。他們之間的相關性以Pearson's correlation test來分析。結果：脈波傳導速率、收縮壓、舒張壓及心跳於麻醉誘導後有顯著的降低，收縮壓與舒張壓於手術劃刀後上升。脈波傳導速率及舒張壓於全身麻醉中，有逐漸下降的趨勢，而收縮壓及心跳則維持穩定。在麻醉停藥後，脈波傳導速率、收縮壓、舒張壓及心跳均有顯著的上升。脈波傳導速率與收縮壓、舒張壓、脈搏壓及平均血壓有明顯的相關性。結論：我們使用簡單且非侵入性的雙通道光容積變化圖的量測，可評估在全身麻醉及手術刺激下，脈波傳導速率的一系列變化；且脈波傳導速率在全身麻醉下與血壓有明顯的相關性。

Background: Increased pulse wave velocity (PWV) is a marker of increased arterial stiffness and is correlated with cardiovascular mortality and mortality of all causes in the elderly and in patients with essential hypertension and type 2 diabetes. There is also a positive correlation between PWV and arterial blood pressure. The changes of PWV in response to general anesthesia and surgical stimulation remain unclear. The aim of this study was to continuously monitor the PWV, blood pressure and heart rate, and to assess their correlations during general anesthesia in women receiving gynecologic surgery. Methods: The values of PWV were obtained from calculation of the finger-to-toe distance divided by the transit time using dual-channel photoplethysmography system. The values of PWV, systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate were recorded before anesthesia induction, 5 min before incision, at incision, in continuation for at least 30 min thereafter, and 5 min after discontinuation of sevoflurane. The correlations between PWV and SBP, DBP and heart rate during the general anesthesia were analyzed using Pearson's correlation test. Results: The serial records of PWV and hemodynamic parameters showed that PWV, SBP, DBP, and heart rate decreased after induction of anesthesia. SBP and DBP increased after surgical incision. There was a trend of progressively declining of PWV and DBP during the general anesthesia but SBP and heart rate remained stationary. All the values of PWV, SBP, DBP, and heart rate increased after discontinuation of anesthesia. There were significant correlations between PWV and SBP (r = 0.4558, P < 0.0001), between PWV and DBP (r = 0.2719, P < 0.0001), between PWV and pulse pressure (r = 0.2067, P < 0.0001), and between PWV and mean arterial pressure (r = 0.3969, P < 0.0001). Conclusions: We could evaluate the serial changes of PWV in response to general anesthesia and surgical stimulation using a simple and noninvasive dual-channel photoplethysmography system. The value of PWV, an index of arterial stiffness, has significant correlation with arterial blood pressure.