Lactic Acidosis: Current Treatments and Future Directions

Area of Science:

• Critical Care Medicine
• Biochemistry
• Physiology

Background:

• Severe lactic acidosis, often caused by sepsis or low-flow states, carries high mortality rates.
• Current treatments focus on addressing underlying causes, but therapeutic options for acidosis itself are limited.
• Sodium bicarbonate administration, while sometimes recommended, has shown no benefit and may cause harm.

Observation:

• Sodium bicarbonate's failure is linked to reduced serum calcium and intracellular acidification from excess carbon dioxide.
• Animal studies suggest hyperventilation and calcium infusion can mitigate bicarbonate's negative effects.
• NHE1 inhibitors and targeting hypoxia or aerobic glycolysis pathways show potential in animal models.

Findings:

• Sodium bicarbonate administration does not improve cardiovascular function or reduce mortality in severe lactic acidosis.
• Alternative buffering agents like THAM or Carbicarb, or dialysis, warrant investigation in human trials.
• NHE1 inhibitors have demonstrated efficacy in animal studies for improving cardiovascular function and reducing mortality.

Implications:

• Further research into alternative buffers and NHE1 inhibitors is crucial for developing more effective human therapies.
• Targeting the mechanisms of lactic acid accumulation, such as tissue hypoxia and altered glycolysis, offers novel therapeutic avenues.
• This case highlights the need for evidence-based approaches to managing acute lactic acidosis.