Purpose: The aims of this study were to test the feasibility and to assess potential recruitment rates in a pilot study preliminary to a phase III randomized trial of decompressive craniectomy surgery in patients with diffuse traumatic brain injury (TBI) and refractory intracranial hypertension.
Materials and methods: A study protocol was developed, inclusion and exclusion criteria were defined, and a standardized surgical technique was established. Neurologic outcomes were assessed 6 months after injury with a validated structured questionnaire and a single trained assessor blind to treatment group.
Results: During the 8-month pilot study at a level 1 trauma center in Melbourne, Australia, 69 intensive care patients with severe TBI were assessed for inclusion. Six patients were eligible, and 5 (8%) were randomized. Six months after injury, 100% of patients received outcome assessments. Key improvements to the multicenter Decompressive Craniectomy study protocol were enabled by the pilot study.
Conclusions: In patients with severe TBI and refractory intracranial hypertension, the frequency of favorable neurologic outcomes (independent living) was low and similar to predicted values (40% favorable). A future multicenter phase III trial involving 18 neurotrauma centers with most sites conservatively recruiting at just 25% of the pilot study rate would require at least 5 years to achieve an estimated 210-patient sample size. Collaboration with neurotrauma centers in countries other than Australia and New Zealand would be required for such a phase III trial to be successful.