Prostacyclin influences the pressure reactivity in patients with severe traumatic brain injury treated with an ICP-targeted therapy.

Background: This prospective consecutive double-blinded randomized study investigated the effect of prostacyclin on pressure reactivity (PR) in severe traumatic brain injured patients. Other aims were to describe PR over time and its relation to outcome.
Methods: Blunt head trauma patients, Glasgow coma scale ≤8, age 15-70 years were included and randomized to prostacyclin treatment (n = 23) or placebo (n = 25). Outcome was assessed using the extended Glasgow outcome scale (GOSE) at 3 months. PR was calculated as the regression coefficient between the hourly mean values of ICP versus MAP. Pressure active/stable was defined as PR ≤0.
Results: Mean PR over 96 h (PRtot) was 0.077 ± 0.168, in the prostacyclin group 0.030 ± 0.153 and in the placebo group 0.120 ± 0.173 (p < 0.02). There was a larger portion of pressure-active/stable patients in the prostacyclin group than in the placebo group (p < 0.05). Intra-individual changes over time were common. PRtot correlated negatively with GOSE score (p < 0.04). PRtot was 0.117 ± 0.182 in the unfavorable (GOSE 1-4) and 0.029 ± 0.140 in the favorable outcome group (GOSE 5-8). Area under the curve for prediction of death (ROC) was 0.742 and for favorable outcome 0.628.
Conclusions: Prostacyclin influenced the PR in a direction of increased pressure stability and a lower PRtot was associated with improved outcome. The individual PR varied substantially over time. The predictive value of PRtot for outcome was not solid enough to be used in the clinical situation.