Lactate Solution Selection During Seizures
During seizures, avoid using Ringer's lactate (lactated Ringer's solution) and instead use 0.9% sodium chloride (normal saline) as the preferred IV fluid, especially in patients with severe head trauma or seizures. 1
Rationale for Avoiding Lactated Ringer's Solution
- Hypotonic solutions such as Ringer's lactate should be specifically avoided in patients with severe head trauma to minimize fluid shift into damaged cerebral tissue 1
- A secondary analysis from the PROMMTT study revealed that Ringer's lactate solutions were associated with higher adjusted mortality compared with normal saline in trauma patients 1
- Seizures are associated with increased lactate production in the body and brain, making additional lactate administration potentially problematic 2, 3
- Lactated Ringer's solution should be avoided in patients with severe head trauma due to its slightly hypotonic nature (277 mOsm/L), as advised by the Critical Care Society 4
Recommended Fluid Choice
- 0.9% sodium chloride (normal saline) is the recommended first-line fluid therapy in patients with seizures, particularly those with traumatic brain injury 1
- If using 0.9% sodium chloride solution, it should be limited to a maximum of 1-1.5 L to avoid hyperchloremic acidosis 1
- Saline solutions should not be used in severe acidosis, especially when associated with hyperchloremia 1
Physiological Considerations
- During seizures, patients develop lactic acidosis due to muscle activity and cerebral metabolism changes 2, 3
- Serum lactate is often elevated following seizures and can remain elevated for several hours 2
- Administering additional lactate through IV fluids may complicate the interpretation of lactate levels as a marker of seizure severity or resolution 5
- Hyperchloremic acidosis is often present as a component of post-seizure acidosis 3
Special Considerations
In patients with seizures and traumatic brain injury, avoid:
Maintain serum glucose concentration between 8 mmol/L (1.4 g/L) and 10-11 mmol/L (1.8-2 g/L) in severe traumatic brain injury patients with seizures 1
Clinical Implications
- While a 30 mL/kg bolus of lactated Ringer's solution may only cause modest increases in serum lactate in healthy individuals 6, patients with seizures already have elevated lactate levels, making interpretation more difficult
- The balanced electrolyte composition of lactated Ringer's solution makes it physiologically more similar to plasma than 0.9% NaCl in most clinical scenarios, but this benefit is outweighed by the risks in seizure patients 4
- Remember that lactated Ringer's solution already contains 4 mmol/L of potassium, which may be relevant when managing electrolyte abnormalities in seizure patients 4
In conclusion, 0.9% sodium chloride is the preferred IV fluid during seizures, particularly in patients with head trauma or risk of cerebral edema, while Ringer's lactate should be avoided due to its hypotonic nature and lactate content.