Responsiveness to therapy for increased intracranial pressure in traumatic brain injury is associated with neurological outcome

Abstract

In patients with severe traumatic brain injury, increased intracranial pressure (ICP) is associated with poor functional outcome or death. Hypertonic saline (HTS) is a hyperosmolar therapy commonly used to treat increased ICP; this study aimed to measure initial patient response to HTS and look for association with patient outcome. Patients >17 years old, admitted and requiring ICP monitoring between 2008 and 2010 at a large urban tertiary care facility were retrospectively enrolled. The first dose of hypertonic saline administered after admission for ICP >19mmHg was recorded and correlated with vital signs recorded at the bedside. The absolute and relative change in ICP at 1 and 2h after HTS administration was calculated. Patients were stratified by mortality and long-term (≥6 months) functional neurological outcome. We identified 46 patients who received at least 1 dose of HTS for ICP>19, of whom 80% were male, mean age 34.4, with a median post-resuscitation GCS score of 6. All patients showed a significant decrease in ICP 1h after HTS administration. Two hours post-administration, survivors showed a further decrease in ICP (43% reduction from baseline), while ICP began to rebound in non-survivors (17% reduction from baseline). When patients were stratified for long-term neurological outcome, results were similar, with a significant difference in groups by 2h after HTS administration. In patients treated with HTS for intracranial hypertension, those who survived or had good neurological outcome, when compared to those who died or had poor outcomes, showed a significantly larger sustained decrease in ICP 2h after administration. This suggests that even early in a patient's treatment, treatment responsiveness is associated with mortality or poor functional outcome. While this work is preliminary, it suggests that early failure to obtain a sustainable response to hyperosmolar therapy may warrant greater treatment intensity or therapy escalation.

Keywords: Hyperosmolar therapy; Hypertonic saline; Intracranial pressure; Traumatic brain injury.