Lactate Intolerant

A 76-year-old woman presented to the ED with altered mental status. Her family said she had increasing fatigue for two days. That morning, the patient had nausea, vomiting, and shoulder pain. EMS found she had a blood glucose of 34. She was given an ampule of D50 and brought to the ED.The patient reported dizziness and fatigue in the ED, and stated that she had not eaten for a few days. Her initial vital signs included temperature 94.1℉, pulse 76 bpm, blood pressure 120/67 mm Hg, respiratory rate 18 bpm, and pulse oximetry 99% on room air. Her physical examination is unremarkable.Initial laboratory values are remarkable for a pH 6.97, HCO3 4, PCO2 18, and lactate 13.5. Initial BMP was remarkable for a HCO3 5, BUN 75, creatinine 5.78, and an anion gap of 30. CBC demonstrated a WBC of 27.1, Hb 12.3, Hct 38.6, and Plt-395. The family said the patient had diabetes and Parkinson's disease. Her medications include sitagliptin, rosuvastatin, telmisartan, and metformin.​Differential for Elevated Lactic AcidosisCyanide poisoningMetformin Associated Lactic Acidosis (MALA)Propylene glycol toxicityAntiretroviral drugsErroneously elevated lactate levels due to interference of the assay with ethylene glycolShockHypoxiaSeizureMetformin is a commonly prescribed medication for diabetes mellitus. It is in the biguanide class of medications, which maintain euglycemia by inhibiting gluconeogenesis, enhancing peripheral glucose uptake and increasing intestinal use of glucose. Metformin does n...
Source: The Tox Cave - Category: Emergency Medicine Tags: Blog Posts Source Type: blogs