From the Guidelines
Lactate should be ordered immediately in patients with suspected sepsis, septic shock, or any condition causing circulatory compromise, as it is a critical marker of tissue hypoperfusion and guides resuscitation efforts. This is based on the most recent and highest quality evidence from the Surviving Sepsis Campaign international guidelines for the management of septic shock and sepsis-associated organ dysfunction in children, published in 2020 1. Specifically, lactate measurement is indicated in patients with signs of sepsis, trauma, cardiac arrest, severe burns, drug overdose, diabetic ketoacidosis, liver failure, or any condition causing circulatory compromise.
Key Indications for Lactate Measurement
- Hypotension (systolic blood pressure <90 mmHg)
- Tachycardia
- Altered mental status
- Respiratory distress
- Other signs of clinical deterioration
Interpretation of Lactate Levels
- Normal lactate levels are typically <2 mmol/L
- Values >4 mmol/L indicate significant tissue hypoperfusion and correlate with increased mortality
- Lactate clearance (reduction in levels over time) is a good prognostic indicator and helps guide resuscitation efforts
Frequency of Lactate Measurement
- Serial lactate measurements are valuable to monitor response to treatment
- Levels should be checked every 2-6 hours depending on clinical status
The use of lactate levels to guide resuscitation is supported by the Surviving Sepsis Campaign guidelines, which suggest using trends in blood lactate levels, in addition to clinical assessment, to guide resuscitation of children with septic shock and other sepsis-associated organ dysfunction 1. Additionally, the guidelines recommend guiding resuscitation to normalize lactate in patients with elevated lactate levels as a marker of tissue hypoperfusion 1.
Overall, lactate measurement is a critical component of sepsis management, and its use should be guided by the most recent and highest quality evidence to optimize patient outcomes.
From the Research
Lactate Measurement in Sepsis
- Lactate measurements have gained a prominent role in sepsis definitions, screening protocols, management guidelines, and quality measures over the past two decades 2.
- Elevations in blood lactate concentrations are associated with increased mortality, and serial lactate levels have demonstrated prognostic accuracy 2.
- Lactate monitoring is central to risk stratification and management of sepsis, and its use has increased dramatically over time 3.
Indications for Lactate Measurement
- Lactate measurement is recommended in patients with suspected sepsis, particularly those with severe sepsis or septic shock 3, 4.
- Lactate clearance is an important indicator of the effectiveness of resuscitation in septic shock patients, and its measurement can help guide therapy 4, 5.
- Norepinephrine dosage is associated with lactate clearance after resuscitation in patients with septic shock, and high-dose norepinephrine is associated with lower lactate clearance and greater 30-day mortality 4.
Timing of Lactate Measurement
- Lactate measurement should be performed at the time of suspected sepsis, and repeat measurements should be made within 6 hours after initial lactate levels ≥ 4.0 mmol/L 3.
- Serial lactate measurements can help monitor the effectiveness of resuscitation and guide adjustments to therapy 3, 5.
- Vasopressin administration is associated with rising serum lactate levels in patients with sepsis, and lactate measurement should be considered when vasopressin is initiated 6.