Lactic Acidosis

Lactate is a warning signal, not a diagnosis. It rises when cells produce lactate faster than the body can clear it, which may reflect shock and impaired oxygen delivery, intense metabolic demand, mitochondrial dysfunction, or impaired hepatic clearance. The immediate clinical question is whether the patient has inadequate tissue perfusion. Elevated lactate accompanied by hypotension, altered mental status, cool or mottled skin, delayed capillary refill, or declining urine output is a shock pattern until proven otherwise. A high value in a hemodynamically stable patient still requires explanation, but it does not automatically mean hypoxemia or septic shock.