Journal Club : DECRA - decompressive craneictomy for refractory intracranial hypertension in TBI

Neil Orford on 27-03-2011

For several years now, neurosurgeons and intensivists have speculated that decrompression of the cranial vault in patients with severe refractory intracranial hypertension may improve clinical outcomes. A number of published case series have supported the notion, though until now there have been no well conducted randomised controlled clinical trials in its favour. DECRA, conducted by the ANZICS clinical trials group, studied 155 patients over a 7 year period, in whom intracranial hypertension was refractory to standard medical management. The therapy arm had reduced intracranial pressures and required less medical ICP control therapy, showing the therapy "worked". Mortality was similar in both arms, but neurological outcomes were worse in the therapy arm, an unexpected result that appears to indicate early decompression reduces favourable outcomes. There are a number of interesting discussion points; 1. How did early decompression convert favourable outcome to unfavourable? Could it be DC allows more oedema leading to stretch of axons and damage? Could it be the DC group achieve ICP control and therfore miss out on medical therapies that may have a benefit separate to ICP ? 2.The accompanying editorial points out that in screening over 3000 patients in 7 years, only 155 patients could be entered into the trial. This can probably be attributed to the exclusion of patients with intracerebral bleeds, perhaps the lack of equipoise in some centers, and the inherent difficulty in conducting such a complex, invasive trial in a population in whom so much is at stake. So where to from here? Follow-up studies to try and understand the mechanism of unfavourable neurological outcome in survivors of TBI and DC? Abandon the use of DC for ICP control? Reconsider target ICP's? Reconsider the threapeutic effect of medical therapies for ICP control? No matter what this study is an incredible achievement by the ANZICS CTG, and is a must read, must discuss contribution to the literature.

5 Comments

Got something to say?

Log in to your account

Forgotten your password?

James Doyle wrote 04-03-2011 10:47:04 am
An impressive study. One query though - the mortality rates were similar but i note (from the study additional information appendix) that 4 of the 82 patients randomised to the standard care arm eventually went on to have some kind of decompressive craniectomy due to the inability to control intracranial hypertension. Furthermore 3 of the 73 patients randomised to craniectomy didn't get one owing to sudden control of their ICP (2 patients) or consent withdraw (1 patient). I wonder if this would have been enough to affect mortality outcomes.

So do we need studies to compare surgical technique? My personal feeling is that further studies would show a reduced mortality and further support increased morbidity. I wonder how many of these young previously healthy patients who end up fully dependant would have gone on (without surgical intervention) to organ donation?

Jo Butler wrote 06-08-2011 10:42:23 pm
Would anyone seriously consider doing this now? We'll just end up with a bunch of severely brain injured survivors.

Todd Fraser wrote 06-09-2011 02:37:54 pm
I guess we need to consider the specifics of the exam Jo. Even though there was no benefit in this cohort, others might. The intervention group only did Decra on those with no other indication for surgery, didn't it? It remains possible that some groups excluded from this trial may still benefit, in the right circumstances.

Benjamin Moran wrote 06-11-2011 10:48:51 am
Looking at the results of the study, the baseline characteristics weren't equal- pupillary reactivity was significantly different. When this was adjusted for in a post hoc analysis, both Extended Glasgow Outcome Score and risk of an unfavorable outcome (EGOS 1-4) were no longer significant. These results were not the final published results in any of the results tables. I dare say that, if the study was larger, this difference would've still been significant.

As for who would still perform a craniectomy in these patients- many of the neurosurgeons at my hospital believe that surgical technique plays a big part in outcome, and they are staunch advocates for the intervention. Try telling these surgeons that they can't operate on a patient when they can see how high their ICPs are, and they have the capacity to reduce those ICPs, particularly in a study, where after adjustment for baseline variability, no significant difference was found (assuming they read past the introduction).

Jo Butler wrote 06-12-2011 06:56:30 pm
Either way, there appears to be little difference between the interventions. Why would you do something so invasive if there is likely to be little benefit, and potentially harm?

Its unfortunately a bit like SAFE - the study appears to be used to support whichever side of the argument you happen to support.