Lactic Acidosis Causes and Mechanisms

Classification and Pathophysiology

Circulatory disorders, including shock, cardiac failure, and severe hypotension, lead to inadequate tissue perfusion and oxygen delivery, causing lactic acidosis, as reported by Thorax 1
Severe infections and sepsis cause tissue hypoperfusion and increased metabolic demands, resulting in lactic acidosis, according to Praxis Medical Insights 2
Acute mesenteric ischemia can cause lactic acidosis due to intestinal hypoperfusion, as stated in the World Journal of Emergency Surgery 4
Respiratory failure resulting in hypoxemia can lead to lactic acidosis, as noted in Thorax 1
Severe anemia limiting oxygen-carrying capacity can cause lactic acidosis, as reported by Praxis Medical Insights 2
Exercise beyond anaerobic threshold when oxygen delivery is insufficient to meet demand can result in lactic acidosis, according to the American Journal of Respiratory and Critical Care Medicine 5
Under normal conditions, lactate is produced during glycolysis and is metabolized by the liver, as stated in Thorax and Praxis Medical Insights 1, 2
In tissue hypoxia, anaerobic metabolism increases with conversion of pyruvate to lactate to regenerate NAD+, as reported by Thorax 1
Mitochondrial dysfunction can occur due to NRTIs inhibiting DNA polymerase γ, responsible for mitochondrial DNA synthesis, as noted in Praxis Medical Insights 2
Thiamine deficiency can affect pyruvate dehydrogenase function, leading to mitochondrial dysfunction, as stated in Praxis Medical Insights 2

Arterial pH <7.35 (acidosis) is a laboratory finding in lactic acidosis, as reported by Thorax and Praxis Medical Insights 1, 2
Blood lactate levels >2 mmol/L (elevated), >5 mmol/L (abnormal), and >10 mmol/L (serious/life-threatening) are indicative of lactic acidosis, according to Praxis Medical Insights 2, 3
Increased anion gap (Na - [Cl+HCO3-] >16) is a laboratory finding in lactic acidosis, as noted in Praxis Medical Insights 2
Gastrointestinal symptoms, such as nausea, vomiting, and abdominal pain, can occur in lactic acidosis, as reported by Praxis Medical Insights 3
Respiratory symptoms, such as tachypnea and dyspnea, can occur in lactic acidosis, as noted in Praxis Medical Insights 2, 3
Neurological symptoms, such as weakness, confusion, and altered mental status, can occur in lactic acidosis, as stated in Praxis Medical Insights 2

Atrial fibrillation, recent myocardial infarction, cardiac failure, and diffuse atherosclerotic disease are risk factors for mesenteric ischemia-related lactic acidosis, as reported by the World Journal of Emergency Surgery 4
Elderly patients (>65 years) have a higher risk for metformin-associated lactic acidosis, as noted in Praxis Medical Insights 3
Patients with short bowel syndrome and preserved colon are at risk for D-lactic acidosis, as stated in Praxis Medical Insights 2
Elevated D-dimer (>0.9 mg/L) may be an independent risk factor for intestinal ischemia causing lactic acidosis, as reported by the World Journal of Emergency Surgery 4