Objectives: To evaluate the significance of diabetes mellitus and metformin in patients admitted to medical ICU with lactic acidosis.
Methods: All the patients admitted to medical ICU with serum lactic acid exceeding 5 mmol/L and pH<7.35 were enrolled into analysis. The impact of diabetes mellitus and metformin treatment on ICU presence of lactic acidosis and its mortality was evaluated. The metabolic parameters were compared with respect to the presence of diabetes mellitus and metformin application.
Results: Lactic acidosis was detected in 69 (4%) out of 1,755 admitted patients, 44 were nondiabetic and 25 had diabetes mellitus, 11 of them treated with metformin. No significant impact of diabetes mellitus or metformin application on presence of lactic acidosis and its mortality was detected. In nondiabetic subjects mortality was associated with eGFR and the presence of acute renal failure while in diabetic patients with sepsis. Acute renal failure was detected in 9 out of 11 patients on metformin. Three patients died due to sepsis, however only 1 out of 6 due to another cause if renal replacement therapy was started soon after admission. The acidosis was more expressed in diabetic subjects mainly in patients taking metformin. It might be attributed to the more pronounced acute renal failure in diabetic patients.
Conclusion: The presence of diabetes mellitus and metformin application is not associated with the presence of lactic acidosis in medical ICU and its mortality. The prognosis of acute renal failure of patients on metformin is good if the subjects with sepsis are excluded.