Relationship between seizures and metabolic acidosis: a prospective observational study

Objective: To assess changes in blood gas parameters, such as pH, partial carbon dioxide pressure (PaCO2), bicarbonate (HCO3), base deficit, and lactate values, in patients who present to the emergency care unit after a seizure. Methods: This is a prospective study on patients who suffered a generalized tonic-clonic seizure. The demographic and biochemical data of the patients and their blood gas parameters were recorded both at the time of presentation to the emergency department and during the follow-up examination. Results: A total of 68 patients were included in the study. Among the patients, 60.3% (41) were male. The median age of the patients was 43 years (IQR: 29-65.25). The median initial lactate value was 5.7 mmol/L (25th and 75th percentiles: 3.5-8.5 mmol/L). The median follow-up lactate value was 1.8 mmol/L (25th and 75th percentiles: 1.1-2.8 mmol/L). The statistical analysis of the blood gas parameters revealed a statistically significant difference in the pH, PaCO2, base deficit, and lactate values between the initial and follow-up evaluations (P<0.001). Conclusion: The results of our study suggest that metabolic acidosis with high anion gap may develop due to the increase in the lactate levels as a result of a tonic-clonic seizure.