Seizures result from an excessive discharge of current from a collection of neurons or brain cells. Sudden changes in electrolyte concentrations can lead to seizures; these seizures are often accompanied by advanced symptoms that reflect an acute derangement in the function of brain cells. These seizures must be addressed quickly to prevent further deficits in function.
The concentration of electrolytes in the blood is partly determined by the regulation of blood volume. Blood volume is regulated by the body to maintain blood pressure but in some cases blood volume is regulated in compensation for changes in the electrolyte concentration. The total volume of water in the body corresponds to roughly 70 percent of body weight. Water in the body is distributed into intracellular and extracellular compartments. The extracellular is further separated into the water between cells and the water contained in blood vessel.
Electrolytes and Water Movement
Electrolytes are present in every compartment of the body but in varying concentrations. Electrolytes can be trapped in their various compartments or move freely between compartments; electrolytes that move freely do not affect the movement of water. The various important electrolytes are sodium, chloride and potassium. Sodium does not freely move between compartments and is therefore the major electrolyte that creates the osmotic force or the attractive force that pulls water into a compartment.
Hypernatremia, or high blood sodium, can be caused by excess water loss or insufficient water intake; because sodium is higher in blood, water is pulled from the cell and into the blood vessel, thereby increasing blood volume and decreasing cell volume. The shrinkage of brain cells decreases their ability to function properly, which contributes to the development of seizures. Hyponatremia, or low blood sodium, can lead to seizures as well by causing the swelling of brain cells.
Management of Sodium Imbalance
The goal in managing hypernatremia is to prevent further loss of water by addressing its cause. The correction of water deficit should not be done rapidly; rapid correction results in rapid shifting of water into cells, causing them to swell and increasing the likelihood for seizures. Water is best given by mouth but in special cases, it can be given through a feeding tube.
Hyponatremia is managed by restricting salt intake and increasing water loss. The body will be reabsorbing sodium, so increasing salt intake could cause another problem.
- "Professionals.Epilepsy.com": Electrolyte Abnormalities
- "Harrison's Principles of Internal Medicine": Kasper M.D.,et al.; 2005