Elevated admission lactate levels in the emergency department are associated with increased 30-day mortality in non-trauma critically ill patients

Abstract

Background Elevated blood lactate levels were reported as useful predictors of clinical outcome and mortality in critically ill patients. To identify higher-risk patients, this investigation evaluated the relationship between patient mortality and admission lactate levels during the management of non-trauma critically ill patients in the emergency department (ED). Methods In this prospective, single centre observational study in a German university ED, all adult patients who were admitted to the ED resuscitation room were evaluated between September 1, 2014 and August 31, 2015. Blood samples for blood gas analysis, including lactate levels, were obtained immediately at admission. Study endpoint was 30-day mortality. Results During the study period, 532 patients were admitted to the resuscitation room of the ED. The data of 523 patients (98.3%) were available. The overall 30-day mortality was 34.2%. Patients presenting to the resuscitation room with admission lactate levels < 2.0 mmol/l had a 30-day mortality of 22.7%, while admission lactate levels above 8.0 mmol/l were associated with higher mortality (8.0–9.9 mmol/l: OR: 2.83, 95%CI: 1.13–7.11, p = 0.03, and ≥ 10 mmol/l: OR: 7.56, 95%CI: 4.18–13.77, p < 0.001). Conclusion High lactate levels at admission are associated with an increased 24-h and 30-day mortality. These measurements may be used not only to predict mortality, but to help identify patients at risk for becoming critically ill. The breakpoint for mortality may be an ALL ≥8.0 mmol/l.

Assessing predictors of futility in patients receiving massive transfusions

“…31 The thresholds used in our study (pH <7.00 and lactate ≥10.0 mmol/L) are representative of severe injury and in line with prior studies. [10][11][12] We acknowledge that the decision to stop transfusing blood is multifactorial in nature and certainly should not be based on laboratory values alone. Patient characteristics, comorbidities, and the nature of the disease process itself should all be taken into consideration, as multiple studies have demonstrated that these factors not only influence the efficacy of RBC transfusion, 32,33 but also impact clinical outcomes.…”

“…Peak lactate was stratified into the following categories: 0.0–4.9, 5.0–9.9, and ≥10.0 mmol/L, while nadir pH was stratified into the following categories: <7.00, 7.00–7.19, 7.20–7.39, and ≥7.40. The peak lactate threshold of 10.0 mmol/L and the nadir pH threshold of 7.00 were chosen based on prior studies in critically ill and trauma surgery patients 10,12 . Patients were also categorized according to age (18–39, 40–64, and ≥65 years) and total RBC transfusion volume (30–39 RBC units, 40–49 RBC units, and ≥50 RBC units) to assess additional clinical variables that could potentially be used as markers of futility in massive transfusions.…”

“…Prior research in critically ill patients and in those suffering from sepsis or cardiac arrest, however, have found that certain pH and lactate values are strongly associated with increased morbidity and mortality. [9][10][11][12][13][14] These studies have allowed physicians to incorporate pH and lactate into their clinical assessment when determining prognosis and future treatments for such patients.…”

“…No studies to date have assessed whether specific laboratory thresholds can be used as indicators of futility, based on their association with high mortality in massively transfused patients. Prior research in critically ill patients and in those suffering from sepsis or cardiac arrest, however, have found that certain pH and lactate values are strongly associated with increased morbidity and mortality 9–14 . These studies have allowed physicians to incorporate pH and lactate into their clinical assessment when determining prognosis and future treatments for such patients.…”

Clinical Utility of Delta Lactate for Predicting Early In-Hospital Mortality in Adult Patients: A Prospective, Multicentric, Cohort Study

“…Although there are a series of early warning scores based on different physiological parameters, which are capable of predicting the risk of deterioration in EDs [ 2 , 3 ], there are still situations in which SAEs could be detected earlier if there was an effective early warning [ 4 ].…”