Serum S100B as a marker of brain damage in the trauma intensive care unit

Introduction

Though computer tomography (CT) is a reliable and accurate method of assessing brain damage after trauma, it also exposes the critically ill patient to considerable stress and is thus unsuitable for frequent follow-ups. The intensivist managing severe traumatic brain injury requires a marker which is reliable, repeatable and non-invasive. Our aim was to determine whether S100B could be such a marker in the intensive care setting, both for isolated traumatic brain injury and for traumatic brain injury with additional multiple trauma.

Methods

Ninety-five critically injured patients have been included in this ongoing multi-center prospective study and assigned to one of three groups, according to their pattern of injury:

Group 1: Isolated traumatic brain injury (n = 50)

Group 2: Traumatic brain injury in combination with multiple trauma (n = 35)

Group 3 (controls): Multiple trauma without traumatic brain injury (n = 10).

All patients are examined by CT on admission. S100B values are determined during the first hours after trauma and daily thereafter for a maximum of 3 weeks and compared to clinical, neurological and laboratory findings and to CT.

Results

S100B is elevated during the first hours after trauma, regardless of whether patients are suffering from traumatic brain injury or not, but drops to normal after 48 hours if patients do not have traumatic brain injury. The further course of S100B differs markedly between survivors and non-survivors. In survivors with traumatic brain injury, S100B decreases post-traumatically and remains normal. In non-survivors with traumatic brain injury, S100 remains elevated and/or increases prior to death. This pattern is most clearly visible in patients with isolated traumatic brain injury.

Conclusion

We consider S100B to be a useful marker in the intensive care setting, both for patients with isolated traumatic brain injury and for patients with additional multiple trauma. S100B is a reliable, repeatable and non-invasive marker and does not expose patients to any additional stress. It provides the intensivist with valuable information regarding the effect of therapy on the one hand and regarding prognosis on the other.