Fluid Balance, Complications, and Brain Tissue Oxygen Tension Monitoring Following Severe Traumatic Brain Injury

Refractory intracranial hypertension (RIH) frequently complicates severe traumatic brain injury (TBI) and is associated with worse outcomes. Aggressive fluid resuscitation contributes to the development of peripheral and pulmonary edema, but an effect on cerebral edema is not well established. Some clinicians, including advocates of the "Lund Concept", practice fluid restriction as a means of limiting cerebral edema and reducing intracranial pressure (ICP). We performed a retrospective cohort study involving 41 consecutive patients with severe TBI to assess the association between fluid balance and the development of RIH or pulmonary complications. There was no difference in cumulative fluid balance between patients who did, or did not, develop RIH. Patients in the tertile with the largest fluid balance were no more likely to develop RIH than those in the more restrictive groups (HR 1.05, 0.78-1.42, P = 0.73). In contrast, there was a strong association between fluid balance and the development of bilateral pulmonary infiltrates, which persisted even after adjusting for Glasgow Coma Scale and Injury Severity Score (HR 1.69, 1.40-2.04, P < 0.0001). The use of P(bt)O(2) monitors to guide therapy was associated with higher cumulative fluid balance, more vasopressor use, and the development of both pulmonary edema and RIH. We found no association between cumulative fluid balance and the development of RIH. However, more judicious volume management has the potential to reduce the occurrence of pulmonary complications. Further research is needed to clarify optimal approaches to fluid management among patients with severe TBI and to guide the interpretation and integration of information derived from P(bt)O(2) monitors.