Clinical use of plasma lactate concentration. Part 1: Physiology, pathophysiology, and measurement

Abstract

The etiology of hyperlactatemia is complex and multifactorial. Understanding the relevant pathophysiology is helpful when characterizing hyperlactatemia in clinical patients.

Clinical use of plasma lactate concentration. Part 2: Prognostic and diagnostic utility and the clinical management of hyperlactatemia

“…If the patient is deemed volume replete, interventions should be directed at other ways to optimize oxygen delivery as clinically indicated, for example transfusion therapy, oxygen support, inotropes. Once efforts to improve oxygen delivery have been exhausted, causes of Type B hyperlactatemia should be considered …”

“…When faced with a patient with hyperlactatemia, it is important to remember that an increase in [LAC] may be an indicator of underlying disease but is not, in and of itself, harmful. 3 If the cause of hyperlactatemia is physiologic, such as exercise or a brief, uncomplicated epileptic seizure, treatment to correct the hyperlactatemia is not indicated. In these patients, [LAC] should decrease quickly following cessation of muscle activity, for example, decreasing by 50% per hour or normalizing within 1-2 hours.…”

“…Increased lactate concentrations ([LAC]) are associated with increased disease severity, morbidity, and mortality in many ill and injured human and veterinary populations . The first part of this review discussed the physiology, pathophysiology, and measurement of lactate. This second part evaluates the clinical utility of lactate as a prognostic indicator and therapeutic guide, the value of measuring lactate concentrations in body fluids other than blood, and the clinical management of hyperlactatemia.…”

Near Infrared Spectrometric Investigations on the behaviour of Lactate

“…Lactate is produced in the human body, even at rest, mostly by the skeletal muscle (40-50%), the brain (13%) and adipose tissue (variable). The renal medulla, gastrointestinal (GI) tract, skin, red & white blood cells and platelets are also lactate-producing sites [1]. In blood, lactate production by the red blood cells, leukocytes (predominantly *Research supported by Engineering and Physical Sciences Research Council, EPSRC Grant.…”

“…The major lactate consuming tissues include the liver (20-30%), the renal cortex (20%) and the myocardium (5-15%). Lactate produced by muscle is converted to glucose by the liver and following its return to muscle is recycled as lactate by muscle glycolysis: the Cori Cycle [1]. The kidneys clear excess lactate in the blood, the renal threshold being 6-10 mmol/L.…”