環境的快速變遷意外頻傳，使得民眾對急診有著高度的期許。但近年來急診壅塞嚴重，至少五成以上病患超過建議的平均等待時間造成延誤就醫的問題，而造成此壅塞的情形主要是因為急診流程的變異和有限的醫療資源。
為提供醫院決策者最佳的解決方案，本研究在醫院利用導入精實(Lean)管理觀點進行流程設計並結合離散事件模擬。其中，為了減少病患的等待時間和使流程間能連續流動，有些無價值作業或流程進行合併並形成單元工程(Cell)，而模擬模式則是用以實行精實系統的工具，且考慮到病患到達、醫護人員診療及檢體檢驗時間的隨機性，因此以最佳化來求解系統中醫師、護理人員的配置，以及等待區(Buffer)上限。
首先除了將檢傷及理學檢查合併成為一個流程，並與靜脈內注射或動脈抽血形成單元工程1外；X-ray或EKG、醫師判讀和給藥形成單元工程2。其最佳人力資源配置結果為各單元工程內各有2名醫師及護理人員，而單元工程前的等待區與待床區則分別設置2、10、53個床位數。而其中平準化的清空病床，致使病患能夠有節奏的進入病房，讓整個急診的流程更加的穩定。
最後，其結果比較分析發現，急診門診病患及急診住院病患在病患的平均等待時間(Average waiting time)分別改善了59.29%和49.61%。因此，以精實管理應用在醫學中心急診部不僅能夠更好的管理，也能增加病患的價值及消除系統中的浪費。

Patients have higher expectation of Emergency department(ED) due the rapidly changing environment of frequent accidents. However, the congestion problem of ED becomes more serious and let 50% of patients wait longer than the suggestion time of the policies because of the dynamic variation of the system and constraint of limited resource.
In order to provide optimal solution for decision maker, this study applies the lean system design and develops the discrete-even simulation model for the current ED system. In order to reduce the waiting time and continue flow of the whole process, certain activities that do not enhance the value will be combined each other as a work cell. The simulation platform will be used to evaluate whether implementing a lean system. Considering resource constraint, the effect of the variation of patient arrival time to the system, the process time of doctor observation, the process time of nurse observation, and the specimens’ result of the completed time will be set as stochastic .Consequently, parameters of allocation doctors, nurses and the buffer size will be conducted by using this platform of optimization.
We decide the process of triage and doctor observation as a solo process and combine the process of nurse observation as a work cell 1, then combine the process of imaging, doctor review, and nurse observation as a work cell 2. The best scenario analysis will be the allocation 2 doctors and 2 nurses in each cell. The buffer size in front of the two cells and ward buffer are 2,10,53, respectively. The strategy of leveled scheduling for inpatient is adapted.
A 59.29% improvement for the outpatient and a 49.61% improvement for the inpatient in waiting time are achieved. Finally, implementing the lean management to the medical-center ED system can make better management, add value to patients and eliminate waste in the system effectively.

張曉卉，民96，創造醫療價值，從「以病人為中心」做起，康健雜誌，105。
行政院衛生署，民99a，實施新急診五級檢傷分類標準 讓緊急醫療資源妥善運用，http://www.doh.gov.tw/CHT2006/DM/SEARCH_RESULT.aspx (1/11，民101取得取得)
行政院衛生署，民99b，醫療機構現況及醫院醫療服務量統計分析，http://www.doh.gov.tw/CHT2006/DisplayStatisticFile.aspx?d=79961 (12/9，民100取得)
楊大和、謝瓊嬉，民97a，電子業向汽車業取經--精實生產在TFT-LCD產業成功的應用，品質月刊，44卷 (9期)，頁8-15。
楊大和、謝瓊嬉，民97b，綜觀『精實系統』的原理、工具及組織，品質月刊， 44卷 (11期), 頁49-55.
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