What is Lactate?
Evidence suggests increased morbidity and mortality for patients with increasing lactate levels or a decreased rate of lactate clearance.
- Tissue Hypoxia and Anaerobic Metabolism (Traditional school of thought)
- Due to decreased clearance rather than increased production in sepsis
- Secondary to down-regulating of pyruvate dehydrogenase in skeletal muscles by inflammatory mediators (Cytokines) and Catecholamines.
- Type A – Poor tissue perfusion or oxygenation of blood (eg, hypotension, cyanosis, cool and mottled extremities). It can be caused by the overproduction of lactate or the underutilization of lactate. For instance, muscular activity, seizures, ischemia, shock, hypoxemia, anemia, CO poisoning.
- Type B - no clinical evidence of poor tissue perfusion or oxygenation exists.
- Type B1 occurs in association with systemic disease, such as renal and hepatic failure, diabetes and malignancy, thiamine deficiency, infection, pancreatitis, short bowel syndrome.
- Type B2 is caused by several classes of drugs and toxins, including biguanides, alcohols, iron, isoniazid, zidovudine, and salicylates.
- Type B3 is due to inborn errors of metabolism.
- Sepsis related Hypoperfusion and Mitochondrial Dysfunction
- Bowel ischemia
- Severe iron-deficiency anemia, Diabetes mellitus
- Liver disease, Kidney Disease
- Alcoholic Ketoacidosis, Pancreatitis
- Malignancy (leukemia, lymphoma, lung cancer)
- Heat stroke, Pheochromocytoma
- Thiamine deficiency (Remember this one during ICU rounds!)
- Inborn errors of metabolism - von Gierke disease, fructose-1,6-diphosphatase deficiency, pyruvate carboxylase deficiency, pyruvate dehydrogenase deficiency, oxidative phosphorylation deficiency, and methylmalonic aciduria.
- MELAS syndrome (mitochondrial encephalopathy, lactic acidosis, and stroke like episodes) - Characterized by migraine like headaches, dementia, hearing loss, ataxia, and episodic vomiting
Click here to listen to Scott Weingart talking about Lactate
- Get familiar with Type B causes of an elevated lactate
- See the medication list and co-morbities while evaluating elevated lactate
EMCrit/Pulmcrit on Lactate
Northwick Park Hospital
Department of Emergency Medicine