What Is the Utility of Measuring Lactate Levels in Patients with Sepsis and Septic Shock?

Abstract

Elevations in blood lactate concentrations have been studied in sepsis and other disease states for decades and are well known to be associated with increased mortality. Many studies have also demonstrated the prognostic accuracy of serial lactate levels, and some have suggested that lactate clearance may be a useful therapeutic target for resuscitation. Lactate measurements have therefore gained an increasingly prominent role in sepsis definitions, screening protocols, management guidelines, and quality measures over the past two decades. The heavy emphasis on lactate monitoring, however, has also generated controversy and concerns. Lactate is not specific to infection and its frequent use for sepsis screening and diagnosis may therefore trigger unnecessary broad-spectrum antibiotic use in some patients. Because hyperlactatemia does not always reflect fluid-responsive hypoperfusion, titrating resuscitation to lactate clearance can also lead to unnecessary fluid and volume overload. More broadly, there is a lack of high-quality evidence demonstrating that initial and serial lactate monitoring leads to better patient-centered outcomes. Indeed, a recent randomized controlled trial comparing resuscitation strategies based on lactate clearance versus normalizing capillary refill time showed no benefit and potential harm with lactate-guided therapy. In this article, we review the basic pathobiology of lactate metabolism and delineate why the traditional paradigm that hyperlactatemia reflects tissue hypoxia is overly simplistic and incomplete. We then review the evidence behind the diagnostic, prognostic, and therapeutic uses of lactate monitoring and place this in the context of evolving sepsis diagnosis and management guidelines.

Comparison of two porcine acute lung injury models: a post-hoc analysis

“…In our study, elevated expression of IL-6 was observed in the lung tissue from LPS-animals probably contributing to significant higher mPAP overtime in this group. Furthermore, elevated lactate levels, decreased base excess and lower pH values may reflect tissue hypoxia and changes in lactate metabolism [ 32 ]. Especially elevated lactate levels over time are associated with higher mortality in critical ill patients [ 32 ].…”

“…Furthermore, elevated lactate levels, decreased base excess and lower pH values may reflect tissue hypoxia and changes in lactate metabolism [ 32 ]. Especially elevated lactate levels over time are associated with higher mortality in critical ill patients [ 32 ]. In addition, the drops in the white blood cell count and thrombocytes are also common in sepsis-induced ARDS.…”

Diagnostic and therapeutic value of biomarkers in urosepsis

“…Relevant studies have shown that when serum Lac is elevated in sepsis patients, the patients tend to have poorer prognosis and higher mortality. 73 , 74 An initial Lac ⩾4.0 mmol/L was associated with a six-fold increased risk of mortality in the acute phase 22 and to some extent represented hypoperfusion in the tissues of septic patients, which was included in the 2016 sepsis and septic shock guidelines for early identification. 1 In patients with septic shock, the initial Lac level and 6-h Lac clearance are associated with 28-day mortality, and it is suggested that Lac should be normalized within 6 h after fluid resuscitation, 23 which can reduce patient mortality, and early normalization of Lac and Lac clearance greater than 50% are reliable predictors of survival in patients with sepsis.…”

Therapie der Sepsis

“…Die Leitlinien schlagen daher auch vor, dass die hämodynamische Stabilisierung eine Normalisierung des Laktatwerts anstreben sollte [4,9]. Es sei jedoch darauf hingewiesen, dass eine Laktatazidose nicht automatisch auf eine Gewebehypoxie hindeutetdie zugrunde liegenden Pathomechanismen sind komplex [12].…”