本研究提出一套以空間解析漫反射光譜（spatially-resolved diffuse reflectance spectroscopy, SR-DRS）為核心之反射式非侵入連續監測系統，期望針對透析治療過程中可能發生之間歇性低氧與末梢低灌注風險進行量測。系統以 690/750/940 nm 多波段 LED 與多個源–檢距（SDS：6、8、10、14 mm）組成感測板，配合「系統響應校正」與人工類神經網路之正、反向模型進行光譜反演，估測光學參數並擷取脈動訊號；並以半體姿閉氣人體實驗模擬透析過程之低氧、低灌注現象，同步以商用裝置 Masimo Radical-7 作為參考，比對心率（HR）、脈搏血氧飽和度（SpO₂）與灌注指數（PI）的趨勢與事件偵測表現。
結果顯示：一、HR 合併分析之皮爾森相關係數r高（r≈0.977），線性迴歸斜率0.981（近1）、截距1.3986（近0）；Bland–Altman 偏差 0.062 bpm、95% 一致性界限 −4.697至4.821 bpm，顯示兩方法無明顯系統性差異且一致性良好。二、於閉氣任務中，雙系統皆能辨識SpO₂ 之「下降—低點—回復」軌跡；依ODI3（下降≥3%）判定，多數受試者由本系統較早觸發事件，惟高飽和區之微幅變化仍受解析度限制。三、PI 在閉氣期多呈同步下降、復原期回升之趨勢，跨裝置雖有絕對值差異，但相對變化與事件排序一致；本系統在上升與下降起始段落多可較早偵測變化。四、整體驗證反映反射式SR-DRS於手指部位之可行性。限制包括樣本數偏少、性別分布不均、裝置幾何與部位差異、以及未以血氣分析作黃金標準比對等。
本研究證實所建系統可於近似透析場域之半躺姿條件下，穩定追蹤心率、偵測早期去飽和與灌注下降，具備臨床導入潛力。未來將朝硬體小型化與貼合設計、運動偽影抑制與事件預警演算法、擴增多樣性樣本與透析病房前瞻研究等方向精進。

This study presents a reflection-mode spatially resolved diffuse reflectance spectroscopy (SR-DRS) system for noninvasive, continuous monitoring of intermittent hypoxemia and peripheral hypoperfusion relevant to hemodialysis. The sensor integrates 690/750/940-nm LEDs with source–detector separations of 6, 8, 10, and 14 mm; with system-response calibration and forward/inverse ANN models, spectra are inverted to estimate optical properties and extract pulsatile signals. A semi-reclined breath-hold human test emulated dialysis conditions and was synchronized with a Masimo Radical-7 to compare HR, SpO₂, and PI. HR agreement was high (r≈0.977; slope 0.981; intercept 1.3986); Bland–Altman bias 0.062 bpm with 95% limits of agreement −4.697 to 4.821 bpm. Both devices showed the SpO₂ “desaturation–nadir–recovery” pattern and, using ODI3, SR-DRS often triggered earlier; PI typically decreased during breath-hold and rebounded during recovery with consistent inter-device trends. Limitations include a small, male-skewed sample, site/geometry differences, and no arterial blood-gas reference. In conclusion, SR-DRS at the finger reliably tracks HR and detects early desaturation and perfusion decline under dialysis-like conditions; future work will pursue hardware miniaturization and coupling, motion-robust/event-warning algorithms, and larger prospective dialysis studies.

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