From the Guidelines
Lactic acidosis is not directly associated with seizures as a cause, but rather as a potential consequence of the intense physical activity and temporary hypoxia that occurs during a seizure, as evidenced by the physiological response of cells switching to anaerobic metabolism and producing lactic acid as a byproduct 1.
Key Points to Consider
- The provided evidence does not directly link lactic acidosis as a cause of seizures but highlights its occurrence in various medical conditions, including those unrelated to seizures.
- The most relevant information regarding lactic acidosis and its potential relationship with seizures is found in the context of physiological responses to intense muscle activity and temporary hypoxia, which can occur during a seizure.
- Healthcare providers should be aware that elevated lactic acid levels following a seizure are expected and typically transient, resolving within hours after the seizure ends.
- If lactic acid levels remain persistently elevated beyond the expected recovery period, this could indicate another underlying problem requiring further investigation.
- The degree of lactic acid elevation may correlate with seizure severity and duration, with more severe seizures potentially causing more significant lactic acidosis.
Clinical Implications
- In clinical practice, the focus should be on managing the underlying cause of seizures and monitoring for any complications, including lactic acidosis.
- The presence of lactic acidosis in a patient with a history of recent seizure should prompt consideration of the seizure as a potential cause of the lactic acidosis, rather than immediately attributing it to another condition.
- Further investigation is warranted if lactic acid levels do not return to normal within the expected timeframe, to rule out other underlying conditions that may be contributing to the elevated lactic acid levels.
From the Research
Association between Lactic Acidosis and Seizures
- Lactic acidosis has been observed in association with seizures, as reported in a case study where a patient presented with severe lactic acidosis following alcohol-related generalized seizures 2.
- The accumulation of lactic acid in the brain can occur due to various conditions, including epileptic seizures, which can lead to a moderate or pronounced decrease in pH 3.
- Seizure states are associated with moderate accumulation of lactic acid, typically around 10 μmol/g, which can contribute to irreversible cell damage in severe cases 3.
- The relationship between lactic acidosis and seizures is complex, and while lactic acidosis can be a consequence of seizures, it is not a direct cause of seizures 2, 3.
Mechanisms and Pathophysiology
- Lactic acidosis can occur due to an increase in lactate production or a decrease in lactate removal, which can be caused by various factors, including tissue hypoxia, shock, and septicemia 4.
- The brain is protected against systemic acidosis, but cerebral intracellular acidosis can occur due to the accumulation of lactic acid, which can be triggered by seizures, hypoxia, and ischemia 3.
- The treatment of lactic acidosis is aimed at addressing the underlying cause, and sodium bicarbonate administration is sometimes used, although its effectiveness is still debated 5, 4.
Clinical Implications
- Lactic acidosis is a common condition encountered in critical care, and elevated lactate levels are important for prognostication 6.
- Not all lactate in the intensive care unit is due to tissue hypoxia or ischemia, and other sources should be evaluated 6.
- The management of lactic acidosis involves identifying and treating the underlying cause, and lactate clearance is an important factor in determining prognosis 6.