乳酸中毒是與metformin 治療相關的一種罕見但可能威脅性命的併發症。目前，使用metformin 的禁忌都是為防範此併發症而建議的，其中，腎功能異常是相當重要的。本研究旨在探討與metformin 相關的乳酸中毒其預後的相關因子及發病前的慢性腎臟病對預後的影響。我們收集過去5 年內住進本院加護病房且符合metformin 相關的乳酸中毒的個案進行回溯性研究，紀錄他們的過去疾病、臨床表徵、生物學資料、治療方式及預後。共收集17 位metformin相關的乳酸中毒個案，發現所有案例都合併急性腎損傷，死亡率是35.3%。與死亡相關的危險因子包括：高APACHE II 分數(p=0.002)，休克(p=0.028)，需要呼吸器(p=0.002) 及升壓劑(p=0.035)；比起死亡個案，存活者住加護病房天數較長(p=0.014)；過去有無慢性腎臟病，並不影響乳酸中毒時的疾病嚴重度及死亡率。本研究顯示metformin 相關的乳酸中毒症其主要決定預後的因子是住院時的疾病嚴重度，糖尿病患使用metformin 治療時，有無合併第3 期慢性腎臟病，並不影響在急性腎損傷之後引發乳酸中毒症之預後。

Lactic acidosis is a rare but life-threatening complication of metformin treatment. The current contraindications to metformin use have been defined for prevention of this adverse event; renal dysfunction is among the most important ones. This study aimed to explore the factors associated with unfavorable outcome of metformin-associated lactic acidosis (MALA) and assess the impact of previous chronic kidney disease (CKD). We conducted a retrospective analysis of patients admitted in ICU with MALA during a five-year period. The premorbid conditions, clinical presentations, biological data, therapeutic strategies and outcomes were recorded. A total of 17 patients with MALA were identified. All of them were accompanied by acute kidney injury and associated with a mortality rate of 35.3%. The factors associated with a fatal outcome were high APACHE (acute physiology and chronic health evaluation) II score (p=0.002), the presence of shock (p=0.028), the requirement for mechanical ventilation (p=0.002) and vasopressors (p=0.035). Compared with non-survivors, the survivors stayed longer in the ICU (p=0.014). There were no significant differences on illness severity and mortality rate between patients with or without previous CKD. In conclusion, the prognosis of MALA is mainly determined by the severity of underlying conditions. Previous stage 3 CKD has no negative influence on the outcome following acute kidney injury.