What can be learned from the DECRA study

There has been a resurgence of interest in the use of decompressive craniectomy for severe traumatic brain injury (TBI). Numerous studies have shown that the procedure can consistently reduce intracranial pressure (ICP), and a significant number of patients achieve a good long-term functional recovery. However, there has been debate regarding clinical indications and patient selection.

The DECRA (Decompressive Craniectomy in Patients with Severe Traumatic Brain Injury) study compared patients who underwent early decompressive craniectomy for diffuse TBI with patients who received standard medical therapy. Of patients, 70% in the craniectomy group had an unfavourable outcome versus 51% in the standard care group (odds ratio 2.21 [95% confidence interval 1.14-4.26]; P=0.02). Based on these results, the authors concluded that decompressive craniectomy was associated with more unfavorable outcomes and that by adopting standard medical therapy rather than surgical decompression the health care system would save millions of dollars. These conclusions are not really supported by closer examination of the basic data. There were problems with randomization such that the patients in the surgical arm appeared to have sustained a more severe primary TBI, the ICP threshold of >20 mm Hg for >15 minutes did not reflect clinical practice, and there was a high crossover rate from the standard care arm to the surgical arm. Because of these problems, the DECRA trial has received a great deal of criticism, and some authorities have claimed that the results should have no influence on clinical practice. This claim is perhaps unfair, and an alternative interpretation is offered.

Overall, the results of the DECRA study showed that a relatively transient and mild increase in ICP (>20 mm Hg for 15 minutes as recruitment criterion) does not imply that there is significant ongoing secondary brain injury, and any potential improvement obtained by surgical decompression may well be offset by surgical morbidity.

The role of decompressive craniectomy when ICP continues to increase ≥20 mm Hg remains to be established. The ongoing RESCUEicp (Randomised Evaluation of Surgery with Craniectomy for Uncontrollable Elevation of Intra-Cranial Pressure) study hopes to address this issue.