Hyponatremia in Traumatic Brain Injury: A Practical Management Protocol

Area of Science:

• Neurology
• Endocrinology
• Critical Care Medicine

Background:

• Hyponatremia (serum sodium <135 mEq/L) is the most common electrolyte disorder in traumatic brain injury (TBI).
• It is an independent predictor of poor neurological outcomes.
• Differentiating between syndrome of inappropriate antidiuretic hormone secretion (SIADH) and cerebral salt wasting (CSW) in TBI-related hyponatremia is challenging.

Purpose of the Study:

• To estimate the incidence of hyponatremia in TBI patients at our center.
• To evaluate the effectiveness of management strategies for TBI-related hyponatremia.
• To develop simple guidelines for correcting hyponatremia in TBI.

Main Methods:

• Retrospective analysis of 1500 consecutively admitted TBI patients.
• Hyponatremia defined as serum sodium <135 mEq/L; natriuresis as urine spot sodium >40 mEq/L.
• Evaluation of TBI incidence, management, and the effect of fludrocortisone therapy.

Main Results:

• The incidence of hyponatremia was 13.2%.
• Early fludrocortisone therapy significantly reduced hospital stay duration (P < 0.05).
• Traumatic subarachnoid hemorrhage was the most common CT finding in hyponatremic patients.

Conclusions:

• Early fludrocortisone initiation in hyponatremia with natriuresis reduces hospital stay.
• This approach is potentially safer in tropical regions where fluid restriction can be detrimental.
• The protocol obviates the need to differentiate between SIADH and CSW.