Identifying high-risk undifferentiated emergency department patients with hyperlactatemia: Predictors of 30-day in-hospital mortality

Ayşen Aydın Kaçar; Ersin Aksay; Başak Bayram; Emre Kıran; Bahar Elif Güldalı

doi:10.4103/tjem.tjem_34_24

Ayşen Aydın Kaçar¹, Ersin Aksay², Başak Bayram³, Emre Kıran⁴, Bahar Elif Güldalı⁴

¹Department of Emergency Medicine, Turgutlu State Hospital, Manisa, Türkiye
²Department of Emergency Medicine, School of Medicine, Izmir Economy University, Kocaeli, Türkiye
³Department of Emergency Medicine, Kocaeli City Hospital, Kocaeli, Türkiye
⁴Department of Emergency Medicine, School of Medicine, Dokuz Eylul University, Izmir, Türkiye

Keywords: Emergency departments, hyperlactatemia, lactate clearance, lactate normalization, lactates, lactic acid, mortality, prognosis

Abstract

BACKGROUND: Hyperlactatemia has been recognized as a significant prognostic indicator in critically ill patients. Nonetheless, there remains a gap in understanding the specific risk factors contributing to increased mortality among undifferentiated emergency department (ED) patients presenting with elevated lactate levels.

OBJECTIVES: The objective of the study is to investigate potential risk factors for 30 day in hospital mortality in ED patients with hyperlactatemia.

METHODS: All nontraumatic adult presentations to the ED who had a lactate level of ≥2.5 mmol/L were included. Comorbidities, vital signs, lactate levels, lactate clearance, lactate normalization, and final diagnosis were compared with 30 day in hospital mortality.

RESULTS: A 30 day in hospital mortality rate of 10.4% was observed in 979 patients. The mortality rate was higher in hypotensive patients (odds ratio [OR] 4.973), in nursing home patients (OR 5.689), and bedridden patients (OR 3.879). The area under the curve for the second lactate level (0.804) was higher than the first lactate level (0.691), and lactate clearance (0.747) for in hospital mortality. A second lactate level >3.15 mmol/l had a sensitivity of 81.3% in predicting in hospital mortality. The OR for mortality was 6.679 in patients without lactate normalization. A higher mortality rate was observed in patients with acute renal failure (OR 4.305), septic shock (OR 4.110), and acute coronary syndrome (OR 2.303).

CONCLUSIONS: A second lactate measurement more accurately predicts in hospital mortality than lactate clearance and the first lactate level in ED patients. Nursing home patients, bed ridden patients, hypotensive patients on initial ED presentation, patients without lactate normalization, and patients with a final diagnosis of acute renal failure, septic shock, and acute coronary syndrome had a higher mortality rate.

How to cite this article: Kaçar AA, Aksay E, Bayram B, Kıran E, Güldalı BE. Identifying high-risk undifferentiated emergency department patients with hyperlactatemia: Predictors of 30-day in-hospital mortality. Turk J Emerg Med 2024;24:158-64.