背 景研究發現加護單位譫妄盛行率高達20%至80%，住院期間發生譫妄常常導致住院日數 延長，認知功能退化，甚至需要入住護理之家。 目 的因為以加護單位老年病人為研究對象，且討論譫妄的相關研究較少，所以，本研究的 目的是建構加護單位老年譫妄的發生率，並且探討影響老年譫妄的危險因子。 方 法本研究採觀察法重複測量設計。以年齡大於65歲且入住加護單位24小時內的個案為對 象，每日兩次使用加護單位譫妄量表（confusion assessment method, CAM-ICU）和警醒 意識程度量表（richmond agitation-sedation scale, RASS）確認譫妄是否發生，收集老年 病人的基本資料、疾病史、APACH II（acute physiology and chronic health evaluation II） 分數和實驗室檢查值。 結 果總共90位老年病人符合收案標準，觀察日數為430天，建立老年譫妄的發生率為75.6% （n = 68）。平均年齡為78.28 ± 7.6，APACH II分數範圍從7 到35，大部份的個案入住加 護單位的原因是呼吸衰竭（73.3%），86.76%的個案在入住加護單位24 hours內發生譫妄 的症狀，其中混合型最多（47.05%），其次是活動低下型．使用邏輯思回歸檢定老年譫 妄的危險因子，包括使用麻醉藥物的數量，用藥的數量，脫水的天數，入住加護單位 前使用類固醇以及出現休克情形，共解釋31.3%的變項。 結 論老年譫妄是加護單位嚴重的議題，健康照護專業人員應該更加注意評估高危險發生譫 妄的老年病人，以達早期發現的目的。

Background: High prevalence rates of deliriumhave been found in intensive care units (ICUs), ranging from 20%to 80%. The development of delirium may prolong length of stay, impair cognition, and result in placement in a nursing home for the patient. Purpose: There is a lack of research focused on the aging population, so the purpose of this study was to establish the incidence rate of delirium among ICU elderly patients and to identify its risk factors. Methods: An observational design with repeatedmeasures was used. Subjects older than 65 years who had been admitted to the ICU within 24 hours were recruited. The Confusion AssessmentMethod for the Intensive CareUnit andRichmond AgitationYSedation Scale were used twice a day to identify subjects experiencing delirium by RA. The demographic data, history of illness, Acute Physiology and Chronic Health Evaluation II scores, and laboratory data of the participants were recorded. Results: Ninety participants were included froma medical ICU. The incidence rate of delirium was 75.6% (n = 68). Average age was 78.28 T 7.6 years; Acute Physiology and Chronic Health Evaluation II scores ranged from 7 to 35. Most participants were diagnosed with respiratory failure (73.3%), and 86.76% of participants developed delirium within 24 hours. The most frequently experienced type of deliriumwas themixed subtype (47.05%); the second most frequently experienced was hypoactive next. The risk factors were analyzed using logistic regression. The number of anesthetic analgesics used, total number of medications prescribed, duration of dehydration, use of corticosteroids before admissions, and shock were identified and explained 31.3% of variance. Conclusions/Implications for Practice: Delirium is a severe problem among elderly patients in the ICU. Healthcare professionals should paymore attention to elderly patients at greater risk for experiencing delirium.