Venoarterial extracorporeal membrane oxygenation as bridge support for refractory catecholamine-resistant shock and severe lactic acidosis in a patient with metformin exposure and multifactorial contributors: A case report

Abstract

A 47-year-old male with type 2 diabetes on metformin and hypertension presented with profound hypoxemia, severe metabolic acidosis (pH unrecordable, lactate  17 mmol/L), and progressive cardiac dysfunction in the setting of presumed sepsis. Despite maximal conventional therapy—including mechanical ventilation, broad-spectrum antimicrobials, and high-dose vasopressors—the patient developed refractory shock and multi-organ dysfunction. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) was initiated on hospital day 2 as hemodynamic bridge support, combined with continuous renal replacement therapy (CRRT). This intervention facilitated stabilization of hemodynamics, correction of acidosis, and improvement in organ function. The patient was successfully decannulated and survived to discharge, though with residual cardiomyopathy. Lactic acidosis in this case was likely multifactorial, with metformin exposure as one potential contributor amid acute kidney injury, hypoperfusion, and possible septic elements. This report describes the use of VA-ECMO as supportive therapy in a complex, refractory critical illness scenario, highlighting the importance of timely multidisciplinary escalation while emphasizing diagnostic challenges in attributing causality and the need for cautious patient selection in such high-risk interventions.