Adrenaline Infusion Typically Increases Lactate by 3-4 mmol/L
Adrenaline (epinephrine) infusion typically increases serum lactate levels by approximately 3-4 mmol/L, with the effect being dose-dependent and independent of changes in tissue perfusion. 1, 2
Mechanism of Lactate Elevation with Adrenaline
Adrenaline causes lactate elevation through several mechanisms:
Direct metabolic effects 3:
- Increases glycogenolysis
- Reduces glucose uptake by tissues
- Inhibits insulin release from the pancreas
- Enhances the Cori cycle (shuttling lactate to liver for glucose production)
Beta-adrenergic stimulation 1:
- Activates glycogenolysis in skeletal muscles
- Increases lactate production independent of tissue perfusion
Quantitative Impact on Lactate Levels
- The mean increase in plasma lactate with adrenaline infusion is approximately 3.2 mmol/L (95% CI: 2.6-3.8 mmol/L) 2
- The geometric mean lactate increment per unit adrenaline dose is 8.2 mmol/L per μg/kg/min (95% CI: 5.8-10.5) 2
- In critically ill patients, adrenaline can increase lactate from baseline levels of around 2.3 mmol/L to 2.9 mmol/L even at relatively low doses 4
- Higher doses may cause more significant elevations, potentially leading to lactic acidosis 2
Clinical Implications
- Diagnostic confusion: Adrenaline-induced lactate elevation can confound the interpretation of lactate as a marker of tissue hypoperfusion 1
- pH changes: Adrenaline infusion can cause a mean decrease in arterial pH of 0.052 units and a decrease in base excess of 3.8 mmol/L 2
- Monitoring considerations: When using adrenaline infusions, lactate levels should be interpreted with caution as they may not accurately reflect tissue perfusion 5
Dose-Response Relationship
- Low-dose epinephrine (<0.3 μg/kg/min) predominantly has beta-2-adrenergic effects with less lactate elevation 5
- Higher doses are more likely to cause significant lactate elevation and potential lactic acidosis 2
- In one study, 84% of patients receiving escalating doses of adrenaline (0.1-0.5 μg/kg/min) had to have the infusion terminated before reaching maximum dose due to lactic acidosis 2
Contrasting Effects with Other Vasopressors
- Unlike adrenaline, dopamine infusion has been associated with a decrease in lactate levels by approximately 1.0 mmol/L 2
- This difference highlights the specific metabolic effect of adrenaline rather than a general effect of all vasopressors
The lactate elevation caused by adrenaline is a direct pharmacological effect and should not be misinterpreted as worsening tissue perfusion when monitoring critically ill patients receiving adrenaline infusions.