Sai Kisei, Miura Naoya, Tsuchiya Asuka, Morita Seiji, Nakagawa Yoshihide
Department of Emergency and Critical Care Medicine, Tokai University School of Medicine, Isehara, JPN.
Cureus. 2025 Mar 25;17(3):e81197. doi: 10.7759/cureus.81197. eCollection 2025 Mar.
Metformin-associated lactic acidosis (MALA) is a rare but life-threatening complication with mortality rates exceeding 10-30%. While renal replacement therapy (RRT) remains the cornerstone of treatment, mechanical circulatory support may be necessary in cases complicated by severe cardiovascular dysfunction. We report a case of severe MALA with unprecedented metabolic derangement successfully treated with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and continuous renal replacement therapy (CRRT). A 39-year-old male with type 2 diabetes mellitus presented with altered mental status following influenza A infection. Initial assessment revealed severe metabolic acidosis (pH 6.355) with markedly elevated lactate (52.7 mmol/L), acute kidney injury, and cardiovascular collapse. Echocardiography demonstrated severe left ventricular dysfunction with an ejection fraction below 20%. Despite initial resuscitation efforts, including high-dose vasopressors, the patient developed cardiac arrest with pulseless electrical activity, requiring cardiopulmonary resuscitation. After the return of spontaneous circulation, VA-ECMO was initiated for refractory shock unresponsive to high-dose vasopressors. MALA was diagnosed based on the clinical presentation and medication history, although metformin levels could not be measured due to assay unavailability. Under combined VA-ECMO and CRRT support, the patient's metabolic parameters improved steadily, with a gradual decrease in lactate levels and an improvement in pH. Left ventricular function recovered significantly, allowing VA-ECMO discontinuation after 26 hours. The patient was successfully weaned from mechanical ventilation with subsequent rehabilitation, achieving discharge with intact cognitive function and no neurological sequelae. By this time, both cardiac and renal functions had normalized. This case demonstrates the successful use of mechanical circulatory support in extreme metabolic derangement and illustrates how viral illnesses can precipitate severe MALA through acute kidney injury. The successful outcome suggests that early recognition and aggressive intervention with combined VA-ECMO and CRRT might be beneficial in selected patients with MALA-induced cardiovascular collapse. This case also highlights the importance of considering MALA in unexplained severe lactic acidosis, particularly in diabetic patients during acute illness.
二甲双胍相关乳酸酸中毒（MALA）是一种罕见但危及生命的并发症，死亡率超过10%-30%。虽然肾脏替代治疗（RRT）仍然是治疗的基石，但在合并严重心血管功能障碍的情况下，可能需要机械循环支持。我们报告一例严重MALA伴前所未有的代谢紊乱病例，成功采用静脉-动脉体外膜肺氧合（VA-ECMO）和持续肾脏替代治疗（CRRT）进行治疗。一名39岁的2型糖尿病男性在感染甲型流感后出现精神状态改变。初始评估显示严重代谢性酸中毒（pH 6.355），乳酸显著升高（52.7 mmol/L），急性肾损伤和心血管衰竭。超声心动图显示严重左心室功能障碍，射血分数低于20%。尽管进行了初始复苏努力，包括使用高剂量血管加压药，但患者仍发生心脏骤停，出现无脉电活动，需要进行心肺复苏。自主循环恢复后，因对高剂量血管加压药无反应的难治性休克而启动VA-ECMO。根据临床表现和用药史诊断为MALA，尽管由于检测方法不可用无法测量二甲双胍水平。在VA-ECMO和CRRT联合支持下，患者的代谢参数稳步改善，乳酸水平逐渐下降，pH值改善。左心室功能显著恢复，26小时后停用VA-ECMO。患者成功脱机并随后康复，出院时认知功能完好，无神经后遗症。此时，心脏和肾脏功能均已恢复正常。该病例证明了机械循环支持在极端代谢紊乱中的成功应用，并说明了病毒性疾病如何通过急性肾损伤引发严重MALA。成功的结果表明，对于MALA引起的心血管衰竭的特定患者，早期识别并积极采用VA-ECMO和CRRT联合干预可能有益。该病例还强调了在不明原因的严重乳酸酸中毒中考虑MALA的重要性，特别是在急性疾病期间的糖尿病患者中。
