ICU · Renal / acid-base
Lactic Acidosis — Type A, B & D, MALA, and Lactate Clearance
Also known as Lactic acidosis · Lactate · Type A lactic acidosis · Type B lactic acidosis · D-lactic acidosis · Metformin-associated lactic acidosis · MALA · Lactate clearance · Cori cycle · Propofol infusion syndrome · PRIS
Lactic acidosis in the ICU — production versus removal, why septic lactate is not all anaerobic, prognostic thresholds (Sepsis-3, Surviving Sepsis Campaign database), lactate-guided resuscitation (Jansen, Jones, ANDROMEDA-SHOCK), drug-induced hyperlactataemia (metformin and the extracorporeal-treatment workgroup, propofol infusion syndrome), D-lactic acidosis, bicarbonate (BICAR-ICU), thiamine and methylene blue.
Checked against its sources on 8 Oct 2026
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Red flags
- Lactate above 4 mmol/L with hypotension carried 44.5% mortality; above 2 mmol/L on vasopressors defines septic shock
- In sepsis, lactate is not all anaerobic — normalising oxygen delivery may not clear it
- No sepsis, hypotension or hypoxia — consider a drug cause and stop it
- High anion gap with a normal lactate in short bowel syndrome — order a D-lactate assay
- Bicarbonate is not routine (BICAR-ICU)
A bedside approach to a raised lactate
Working through hyperlactataemia
- Is there hypoperfusion? Septic shock is a vasopressor requirement for MAP 65 mmHg or more plus lactate above 2 mmol/L without hypovolaemia.[8]
- Is sepsis driving lactate beyond hypoxia? Aerobic glycolysis, adrenergic stimulation, mitochondrial dysfunction and impaired hepatic clearance all contribute.[2][3]
- Is there a drug? With no sepsis, hypotension or hypoxia, consider toxicology; metformin with renal impairment is the commonest ICU scenario.[13][10]
- Is the lactate normal but the anion gap high? Think D-lactate in short bowel syndrome.[15]
- Treat the cause, then decide on extracorporeal removal or bicarbonate case by case.[11][17]
References20ShowHide
- [1]Kamel KS, Oh MS, Halperin ML L-lactic acidosis: pathophysiology, classification, and causes; emphasis on biochemical and metabolic basis. Kidney international, 2020.PMID 31784049
- [2]Ahmad R, Basha NR, Kumar M, et al. Shock: Pathophysiology, Classification, and the Role of Lactate in Diagnosis and Prognosis. Cardiology in review, 2026.PMID 41563115
- [3]Suetrong B, Walley KR Lactic Acidosis in Sepsis: It's Not All Anaerobic: Implications for Diagnosis and Management. Chest, 2016.PMID 26378980
- [4]Jansen TC, van Bommel J, Schoonderbeek FJ, et al. Early lactate-guided therapy in intensive care unit patients: a multicenter, open-label, randomized controlled trial. American journal of respiratory and critical care medicine, 2010.PMID 20463176
- [5]Jones AE, Shapiro NI, Trzeciak S, et al. Lactate clearance vs central venous oxygen saturation as goals of early sepsis therapy: a randomized clinical trial. JAMA, 2010.PMID 20179283
- [6]Hernández G, Ospina-Tascón GA, Damiani LP, et al. Effect of a Resuscitation Strategy Targeting Peripheral Perfusion Status vs Serum Lactate Levels on 28-Day Mortality Among Patients With Septic Shock: The ANDROMEDA-SHOCK Randomized Clinical Trial. JAMA, 2019.PMID 30772908
- [7]Casserly B, Phillips GS, Schorr C, et al. Lactate measurements in sepsis-induced tissue hypoperfusion: results from the Surviving Sepsis Campaign database. Critical care medicine, 2015.PMID 25479113
- [8]Singer M, Deutschman CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA, 2016.PMID 26903338
- [9]Salpeter SR, Greyber E, Pasternak GA, et al. Risk of fatal and nonfatal lactic acidosis with metformin use in type 2 diabetes mellitus. The Cochrane database of systematic reviews, 2010.PMID 20091535
- [10]See KC Metformin-associated lactic acidosis: A mini review of pathophysiology, diagnosis and management in critically ill patients. World journal of diabetes, 2024.PMID 38983827
- [11]Calello DP, Liu KD, Wiegand TJ, et al. Extracorporeal Treatment for Metformin Poisoning: Systematic Review and Recommendations From the Extracorporeal Treatments in Poisoning Workgroup. Critical care medicine, 2015.PMID 25860205
- [12]Kam PC, Cardone D Propofol infusion syndrome. Anaesthesia, 2007.PMID 17567345
- [13]Blohm E, Lai J, Neavyn M Drug-induced hyperlactatemia. Clinical toxicology (Philadelphia, Pa.), 2017.PMID 28447886
- [14]Kowlgi NG, Chhabra L D-lactic acidosis: an underrecognized complication of short bowel syndrome. Gastroenterology research and practice, 2015.PMID 25977687
- [15]Uribarri J, Oh MS, Carroll HJ D-lactic acidosis. A review of clinical presentation, biochemical features, and pathophysiologic mechanisms. Medicine, 1998.PMID 9556700
- [16]Bianchetti DGAM, Amelio GS, Lava SAG, et al. D-lactic acidosis in humans: systematic literature review. Pediatric nephrology (Berlin, Germany), 2018.PMID 29218437
- [17]Jaber S, Paugam C, Futier E, et al. Sodium bicarbonate therapy for patients with severe metabolic acidaemia in the intensive care unit (BICAR-ICU): a multicentre, open-label, randomised controlled, phase 3 trial. Lancet (London, England), 2018.PMID 29910040
- [18]Donnino MW, Carney E, Cocchi MN, et al. Thiamine deficiency in critically ill patients with sepsis. Journal of critical care, 2010.PMID 20646908
- [19]Donnino MW, Andersen LW, Chase M, et al. Randomized, Double-Blind, Placebo-Controlled Trial of Thiamine as a Metabolic Resuscitator in Septic Shock: A Pilot Study. Critical care medicine, 2016.PMID 26771781
- [20]Zhao CC, Zhai YJ, Hu ZJ, et al. Efficacy and safety of methylene blue in patients with vasodilatory shock: A systematic review and meta-analysis. Frontiers in medicine, 2022.PMID 36237547