Lactic acidosis associated with metformin

Abstract

Metformin is an oral antidiabetic that belongs to the group of the biguainides. It is the drug of choice for the treatment of type II diabetes due to its efficacy and safety. It is a small molecule, whose elimination half-life is 8 to 20 hours in people with normal renal function.

Severe lactic acidosis associated with metformin is a serious, infrequent disease (its incidence is estimated between 3-8 cases per 100,000 diabetic patients and year) but with high mortality (around 40% in accidental poisonings), which is defined in presence of a pH <7.35, lactate> 2 mmol / L and a paCO2 in normal limits.

We present the case of a diabetic patient under treatment with metformin, hypertense and dyslipidemic, polymedicated, with severe lactic acidosis, in a Reanimation Care unit, after postoperative exploratory laparotomy due to suspicion of intestinal ischemia. He arrives in a state of circulatory shock, with little response to the administration of volume and vasoactive drugs.

We describe some data about its incidence, pathophysiology, prognosis and treatment, as well as the importance of an early and differential diagnosis with other causes of metabolic acidosis that elevate the GAP anion.