Lactic Acidosis - Differential Diagnosis Framework Type A: Impaired O2 Delivery (DO2) • Decreased O2 Delivery: Hypotension & Hypovolemia, Trauma & burns, Cardiogenic & Septic Shock, Severe Anemia, Cardiac Arrest, Severe Hypoxemia, Regional Ischemia, Compartment Syndrome • Increased O2 Demand: Stress / Pain / Exercise, Fever, Hypothermia & Shivering, Seizures, Beta-Agonists, ↑ work of breathing, Localized soft-tissue infection, Mesenteric Ischemia, Microcirculatory dysfunction Type B: Impaired O2 Utilization (VO2) • Drugs/Toxins: - Propofol (PRIS), Valproic Acid, Biguanides (Metformin), Linezolid, Lactulose, HIV Antiretrovirals (esp. NRTIs), Acetaminophen, Ethanol, Methanol & Other toxic alcohols, Sodium Nitroprusside, Others (ie. Ricin, Strychnine, Niacin, Salicylates, Isoniazid) • Impaired Clearance: Systemic liver Failure, Renal failure, Mitochondrial dysfunction, Inborn Errors of Metabolism • Other: - Infections (ie. HIV, Malaria, Late Sepsis), Malignancy (Leukemia/Lymphoma), Diabetes Mellitus +/- DKA, Alcoholic lactic acidosis, Deficiencies (Thiamine & Biotin) Type D: Bacterial Overgrowth • Presents as AG acidosis with negative lactate. Difficult to diagnosis as it requires separate D-lactate testing • Seen in Short Bowel Syndrome, where decreased carbohydrate digestion leads to presence of additional sugars in the colon. • Bacteria ferment and convert these sugars into D-Lactate Excerpted from original infographic by Nick Mark MD @nickmmark #Lactic #Acidosis #Differential #Diagnosis #criticalcare #lactate